MARINE LIFE
The natural values of the Arrábida coast are its greatest wealth. More than 2000 species have already been recorded in these waters! It is this treasure that Parque Marinho tries to protect.
Pentapora fascialis
©João Pedro Silva
This banded bryozoan is actually a colony of several small individuals. It grows on rocky bottoms with good water flow and can colonize small stones in areas of coarse sand.
Antipathella wollastoni
©Armando Ribeiro
The black coral owes its name for the black color of their skeleton. The branches have a different coulor like white, green, orange or reddish brown. They are slow-growing organisms, that grow less than 1 cm a year, and reach ages over 100 years old.
Facelina quatrefagesi
©João Pedro Silva
This nudibranch or sea slug can be found in dimly lit areas of rocky bottoms, where it feeds on hydrozoans (small colonial animals). It is a rarely seen species, with only a few records.
Scorpaena maderensis
©João Pedro Silva
The Madeira rockfish lives in rocky reefs, finding shelter in rock crevices and overhangs, where it waits for the prey to approach, capturing it with a fast movement. The rays of the dorsal fin contain a painful poison.
Melanella alba
©João Pedro Silva
This small gastropod grows up to 20 mm in length. It can be found on stones in sandy and muddy or gravel bottoms and is often associated with sea cucumbers.
Caloria elegans
©João Pedro Silva
This sea slug lives on rocky bottoms, usually in dimly lit areas, where it feeds on various species of hydrozoans (tiny colonial animals). It can reach 20 mm in length.
Diplodus sargus
©Emanuel Gonçalves
The white seabream usually lives in shoals that also include other species of seabream. The juveniles are common in estuaries and seagrasses meadows. It is a commercial value fish, most of it coming from aquaculture.
Periclimenes scriptus
©João Pedro Silva
The transparent partner shrimp often lives associated with anemones, soft corals and sea fans. However, there are also records of observations in seagrass meadows and among algae, sometimes in numerous groups.
Gobius cruentatus
©Emanuel Gonçalves
The red-mouthed goby can reach 18 cm in length and is found at low depths, on rocky or sandy bottoms and seagrasses meadows. It is a low-value fish but quite enjoyed in some regions.
Amphorina farrani
©João Pedro Silva
This nudibranch, or sea slug, grows up to 20 mm but is usually smaller. It can be found in crevices and dimly lit areas of rocky bottoms, where it feeds on various species of hydrozoans (small colonial animals).
Serranus cabrilla
©Emanuel Gonçalves
The comber is a hermaphrodite fish, in which every individual can be either female or male. If a sex partner cannot be found during the mating season, the ability to self-fertilize has already been documented. The comber becomes sexual mature when it reaches the length of approximately 15 cm.
Tritonia manicata
©João Pedro Silva
This nudibranch is difficult to observe due to its small size, about 15 mm, and its camouflage. It lives on rocky bottoms and feeds on small soft corals that grow between sponges and algae.
Syngnathus acus
©Emanuel Gonçalves
Like other fish in this family, which includes seahorses, the greater pipefish female deposits its eggs into the male’s brood pouch, where they are fertilized. This pouch can hold up to 400 eggs from several females.
Axinella polypoides
©Nuno Vasco Rodrigues
The common antler sponge grows vertically up to 40 cm. Its surface is smooth with colours ranging from yellow to orange, and it contains several pores through which water and food enter. It can filter up to 200,000 times its body volume per day.
Lanice conchilega
©Emanuel Gonçalves
When gathered in large numbers, the sand mason worm can be considered a reef builder, as the clusters that it forms, significantly change the habitat around it, influencing the presence of other organisms.
Chelidonichthys lastoviza
©Emanuel Gonçalves
When it feels threatened, the streaked gurnard opens his pectoral fins and displays his blue spots to scare away any predators. It is also believed that they play a role in courtship during the mating season.
Eudendrium arbuscula
©João Pedro Silva
This hydrozoan forms shrub-shaped colonies, quite branched and with polyps at the ends. It can be found on rocky bottoms at low depth, in places subject to the action of the tide and on buoys in the open sea.
Alcyonium coralloides
©Rui Guerra
The coral-like sea finger is mainly found on rocks or caves vertical surfaces, growing in lobe-shaped colonies. In some places, it can become a parasite by growing on other coral species.
Coris julis
©Emanuel Gonçalves
The rainbow wrasse goes through two phases of sexual development. In the first phase there are individuals of both sexes, but when they reach the second phase, they all become males. Fishes bigger than 18cm in length, are all second phase males.
Echinaster sepositus
©João Pedro Silva
The red starfish is one of the most common species of these animals in Portuguese waters. It lives on rocky, sandy bottoms and in seagrasses meadows, where it feeds on organic matter. There is no larval phase, from the eggs hatch small starfish.
Symphodus cinereus
©Rui Guerra
The grey wrasse is consumed in some places, but it is also an interesting fish for the aquarium trade.
Felimare bilineata
©João Pedro Silva
This nudibranch (animals belonging to the sea slug group) can reach 25 mm in length. It lives on rocky bottoms, where it feeds on sponges.
Sepia officinallis
©Emanuel Gonçalves
The cuttlefish is a cephalopod mollusc, of nocturnal habits, that lives buried in sandy and muddy bottoms during the day. It has a high commercial value, and its aquaculture production is being studied.
Lanice conchilega
©João Pedro Silva
The sand mason worm builds tubes by secreting mucus that cements sand, pieces of shells and small stones. These are branched at the top, above the substrate, and support the worm’s tentacles while they are searching for food.
Tripterygion delaisi
©Emanuel Gonçalves
During the reproductive season, the black-faced blenny male displays a territorial behavior and a more vivid coloration, unlike females and immature males. It is found in crevices and cavities on rocks and feeds on small crustaceans
Symphodus bailloni
©Rui Guerra
The Baillon’s wrasse lives in shallow areas, rocky reefs covered with algae and seagrass meadows, where it feeds on worms, molluscs and crustaceans. It may also feed on parasites from other fish.
Alcyonium glomeratum
©João Pedro Silva
This false coral, also called red sea fingers, is distinguished from other similar species by having a redder colour and favouring areas of weaker currents. The colonies of this species are branched and narrow, hardly exceeding 2 cm in width.
Loligo sp.
©João Pedro Silva
The squid’s breeding season occurs throughout the year. After mating the females usually lay its eggs in holes or rock crevices. They are arranged in up to twenty sac-like structures, with around 200 to 300 eggs each.
Conger conger
©Emanuel Gonçalves
Unlike most fish, the conger eel does not have scales. It can measure up to 3 meters and has a nocturnal behavior, spending the day sheltered in crevices or holes on rocks. It feeds on other fish, crustaceans and cephalopods and only reproduces once in a lifetime.
Trapania tartanella
©João Pedro Silva
This small nudibranch, or sea slug, has a translucent body which allows the internal organs to be seen. It is found in rocky reefs covered with sponges and sea squirts, on which grow the small animals from which it feeds.
Sertularella gayi
©João Pedro Silva
The polyps of this hydrozoan grow in branched colonies, attached to rocks in areas of moderate water flow. Polyps feed on planktonic organisms that they capture with their tentacles.
Echiichthys vipera
©Rui Guerra
The lesser weaver is one of the most feared seashore animals, as it is common for bathers to step on its dorsal fin rays when they are buried. These rays contain a poison that causes severe pain.
Periclimenes sagittifer
©João Pedro Silva
The Atlantic partner shrimp lives associated with anemones, especially the snakelocks anemone, benefiting from its protection. It has been observed to feed on the tips of the tentacles of the anemone.
Pycnoclavella aurilucens
©João Pedro Silva
The small neon sea squirt grows in colonies over rocky bottoms at low depth, in areas exposed to moderate water flow. However, it can also grow on kelp and other seaweeds. These animals feed on planktonic organisms through water filtration.
Palaemon serratus
©João Pedro Silva
The common shrimp usually lives in groups inside caves and rock crevices, but also in seagrass meadows. To avoid the countless predators, it is more active at night. Its also fished for human consumption.
Felimida krohni
©João Pedro Silva
This is one of the most common species of nudibranchs (or sea slugs) on the Portuguese coast. It can reach 30 mm in length and is usually found in dimly lit places and under stones on rocky bottoms, where it feeds on sponges.
Atrina fragilis
©Rui Guerra
The fan mussel is one of the largest bivalves on the Portuguese coast. It lives partially buried in the sea bed where it attaches due to a golden and very strong thread – the byssus - once used in luxury accessories’ manufacturing.
Zostera marina
©Rui Guerra
The seagrass meadows formed by plants such as this eelgrass are unique habitats in the preservation of biodiversity. They also serve as a nursery to countless species of animals, as is the case of this gastropod eggs.
Gobius cruentatus
©João Pedro Silva
The red-mouthed goby can reach 18 cm in length and is found at low depths, on rocky or sandy bottoms and seagrasses meadows. It is a low-value fish but quite enjoyed in some regions.
Discocelis tigrina
©João Pedro Silva
This flatworm inhabits at low depths, in places sheltered from light and under rocks. It is a little known species, but like other animals of the same group, it has great regenerative capabilities.
Clavularia crassa
©Emanuel Gonçalves
This soft coral’s polyps have the ability to partially retract if disturbed. When fully opened, their tentacles are responsible for capturing planktonic organisms from which the polyp feeds.
Cerianthus sp.
©Emanuel Gonçalves
The tube anemones build the tubes where they live by secreting a cell embedded mucus that results in a fibrous texture, where sediment particles are also added. When it feels threatened, it retracts completely into the tube.
Monochirus hispidus
©João Pedro Silva
The whiskered sole is a flatfish with some commercial value. It lives on sandy and muddy bottoms, up to 150 meters deep.
Hippocampus guttulatus
©Luís Quinta
Like all seahorse species, this one is also protected by many international regulations. Its biggest threats are their habitat’s destruction, the illegal capture for traditional medicine and the aquarium trade.
Pagrus auriga
©Emanuel Gonçalves
As a juvenile, it is common to find the red-banded seabream in shallower waters, unlike the adults. It lives near rocky bottoms, where it feeds on bivalves, crustaceans and cephalopods such as squids. It is a commercially valuable fish.
Thysanozoon brocchii
©João Pedro Silva
This flatworm is usually hidden in crevices or under rocks during the day, coming out at night to feed, mainly on sea squirts.
Felimare tricolor
©João Pedro Silva
This sea slug can reach 30 mm in length, although usually smaller. It is found in dimly lit places of rocky bottoms, where it feeds on sponges.
Ovos de peixe
©Rui Guerra
Several fishes in the blenny family lay their eggs in crevices, under rocks or inside shells. The eyes are usually the first organs to be visible. When they hatch, the larvae are dispersed in the water.
Doriopsilla areolata
©João Pedro Silva
This rounded-body sea slug can reach 40 mm in length. It feeds on sponges in rocky reefs and muddy bottoms. Its eggs are laid in spiral yellow ribbons.
Amphorina linensis
©João Pedro Silva
several This nudibranch, or sea slug, grows up to 20 mm but is usually smaller. It can be found in crevices and dimly lit areas of rocky bottoms, where it feeds on various species of hydrozoans (small colonial animals).
Pycnoclavella communis
©Áthila Bertoncini
The sea squirts were the first animals to develop a dorsal nerve cord (precursor structure of the spine). This small species lives in groups of many individuals and feeds by filtering water.
Facelina annulicornis
©João Pedro Silva
This nudibranch or sea slug can be found in dimly lit areas of rocky bottoms, covered with debris and small colonial animals such as bryozoans and hydrozoans from which it feeds, as well as from other sea slugs.
Tritonia plebeia
©João Pedro Silva
This sea slug can reach 30 mm in size. It lives on rocky and dimly lit bottoms, between bryozoans (small colonial animals) and soft corals, from which it feeds and where it lays its eggs.
Anilocra physodes
©João Pedro Silva
This small crustacean is a parasite of several fish species, usually found attached to the host’s skin by means of powerful hooks on the legs end. In case of a small smize host, this parasitic relation may cause the fish death.
Cerianthus membranaceus
©João Pedro Silva
The Mediterranean tube anemone lives on sand and muddy bottoms. The tentacles are arranged in two sets in which the outer one, with longer and stinging tentacles, is responsible for capturing small fish and plankton.
Aldisa smaragdina
©João Pedro Silva
This mollusc, which reaches up to 30 mm in length, has an excellent camouflage ability. It can be found under stones on rocky bottoms at low depth, usually over a red encrusting sponge from which it also feeds.
Spondyliosoma cantharus
©João Pedro Silva
The black seabream can be found in rocky or sandy bottoms. It feeds on both algae and small invertebrates, especially crustaceans. It can form very numerous shoals and is a fish of commercial interest.
Ascidia sp.
©João Pedro Silva
The ascidians are an extremely diverse group of animals capable of adapting to numerous marine habitats. Besides being included in the diet in some countries, they also have great potential in the development of new chemical compounds useful for Man.
Holothuria sp.
©Emanuel Gonçalves
In recent years, sea cucumbers have undergone intense exploitation, mainly for Asian markets, where they are used in traditional medicine. They are also of gastronomic interest, which has led to attempts to produce them in aquaculture.
Phalacrocorax aristotelis
©Luís Quinta
The European shag is a bird exclusively from coastal areas. He is a resident species in Portugal and is therefore observable all year round. It’s an excellent swimmer and can dive up to 45 meters deep in hunting the fish that make up his diet.
Phallusia fumigata
©João Pedro Silva
The black sea squirt can usually be found in dimly lit areas, on rocks or stones. It feeds on planktonic organisms that are filtered inside its body.
Paramuricea clavata
©Armando Ribeiro
This sea fan is regarded as an ecosystem engineer, as its presence significantly alters the water flow, the sedimentation of the particles, among other factors, which help create habitats for many other organisms.
Flabellina gaditana
©João Pedro Silva
This is a sea slug difficult to observe, given its small size (it has a maximum length of 8 mm). Its body shape and colour are also responsible for its outstanding camouflage. It lives at small depths, in dimly lit places and under rocks.
Scomber colias
©Rui Guerra
The chub mackerel is a migratory fish that forms large shoals. These "fish balls" lie near the bottom of the sea during the day, approaching the surface at night, where they feed on squid, crustaceans and other fish. It is an important species for the fishing sector.
Leptogorgia sarmentosa
©Rui Guerra
The orange sea fan grows on partially sand covered stones and rocks, in areas normally exposed water currents. It can be found up to 300 meters deep.
Aplidium punctum
©João Pedro Silva
The body of sea-squirts is usually coated by a thick layer, called tunic, which in many cases contains cellulose in its composition. This colonial sea-squirt grows in clusters from a foot attached to rocks, stones or shells on current exposed zones.
Atheryna presbyter
©Emanuel Gonçalves
The sand smelt lives in schools in coastal areas and near estuaries, although during winter it migrates to deeper waters. It feeds on small crustaceans and larvae of other fish. In some places of Portugal is a gastronomic delicacy.
Scyllarus arctus
©João Pedro Silva
The small European locust lobster is a nocturnal animal, hiding in holes or crevices in the rocks during the day. It has some commercial value, although its fisheries are not very expressive.
Muraena helena
©Emanuel Gonçalves
The moray eel is a territorial fish of nocturnal habits, spending the day hidden in crevices and holes on rocks. It feeds on other fish, crustaceans and squids. It is caught for human consumption and from its skin, it is possible to craft a leather variety.
Galathea strigosa
©João Pedro Silva
This spiny squat lobster, although edible and appreciated in some places, is not considered a commercial value species. It inhabits rocky areas, crevices and caves, from shallow water down to 600 meters.
Pycnoclavella taureanensis
©João Pedro Silva
Small colonial white sea squirt that grows on rocky bottoms at low depth. The colony individuals, or zooids, disappear during the winter, grow back in the spring and breed in the summer.
Balistes capriscus
©Emanuel Gonçalves
After hatching, the gray triggerfish larvae migrate to the sea surface, seeking shelter amongst the floating communities of sargassum and other seaweeds. They feed on the algae and also on small invertebrates, until they reach juvenile size.
Gobius xanthocephalus
©Emanuel Gonçalves
The golden goby lives at low depths, over rocky bottoms or seagrass meadows. It feeds on small invertebrates and it can reach 10 cm length.
Alcyonium digitatum
©João Pedro Silva
Due to the way its colonies develop, this coral is also called the dead man’s finger. It grows on rocky bottoms, sheltered from light, but with strong water movement. Usually, the polyps of each colony have the same sex.
Berthella stellata
©João Pedro Silva
This sea slug’s digestive gland is easily visible, thanks to its transparent body. It is often found under rocks in the seashore or at low depth. It is a hermaphrodite animal that grows to 35 mm in length.
Polycarpa pomaria
©João Pedro Silva
This solitary sea squirt lives on rocky bottoms or stones and shells. It often incorporates sediment particles or shell fragments in its tunic – an external membrane that covers the body. It feeds on suspended matter that filters inside the body.
Leucosolenia complicata
©João Pedro Silva
This sea sponge has a fragile consistency and grows on rocky bottoms at low depths, usually in sheltered areas such as rocky overhangs or caves. It can also be found in zones with more sediments such as estuaries.
Serranus hepatus
©João Pedro Silva
The brown comber lives on rock, sandy or muddy bottoms, but also in seagrass meadows. It feeds on small fish and invertebrates. It is a simultaneous hermaphrodite, in which each individual has male and female sexual organs at the same time.
Favorinus branchialis
©João Pedro Silva
This nudibranch or sea slug can reach 25 mm in length, although it is usually smaller. It is difficult to observe and is typically found near other sea slugs’ eggs, from which it feeds.
Sepia officinallis
©Emanuel Gonçalves
Throughout their short life, usually no more than 2 years, adult cuttlefish migrate from deeper waters during spring and summer to areas closer to the coast in order to breed. Females can lay up to 4000 eggs.
Aplysia punctata
©João Pedro Silva
The dotted sea hare is an inner shell mollusc. It is usually found in shallow water, next to the algae from which it feeds. It can consume up to a third of its body weight per day, changing its color depending on the species of algae ingested.
Bispira volutacornis
©Emanuel Gonçalves
The twin fan worm feeds on suspended particles that are captured through its feather-like tentacles. These tentacles have light-sensitive cells that allow the animal to quickly withdraw into the tube if threatened or disturbed.
Aeolidiella sanguinea
©João Pedro Silva
Measuring up to 45 mm, this sea slug can be found under rocks at low depths, where it feeds on a wide variety of anemones. It has reddish body covered with appendages that may change colour depending on the ingested food.
Aglaophenia pluma
©João Pedro Silva
The podded hydroid is a tiny animal that forms feather-shaped colonies that reach 3 cm in height. Within these colonies, pinecone shaped reproductive structures may be observed. This species can sting humans, causing swelling in the affected area.
Polycera quadrilineata
©João Pedro Silva
Nudibranch, or sea slug, that can reach 40 mm in length, although not commonly. It lives on rocky bottoms, under stones or among algae, where it feeds on several bryozoans (tiny colonial animals).
Ocinebrina aciculata
©João Pedro Silva
The coralline sting winkle lives on stones, rocks and algae such as kelp, from the surface to depths of about 900 meters.
Sarpa salpa
©João Pedro Silva
The cow bream forms schools sometimes numerous, on rocky areas or seagrass meadows. Juveniles feed on planktonic organisms, while adults are exclusively herbivores. This fish has a low commercial value.
Morus bassanus
©Luís Quinta
The northern gannet is the largest seabird in Portugal. It usually lives at the sea only coming ashore for the breeding season. It feeds on several fish that it hunts by plunge-diving, sometimes up to 40 meters deep.
Hippocampus guttulatus
©Emanuel Gonçalves
The long-snouted seahorse lives mostly at low depths, on algae-covered bottoms and in seagrass meadows. It feeds on small crustaceans, larvae and other planktonic organisms.
Serranus cabrilla
©Emanuel Gonçalves
The comber lives on rocky, sandy or muddy bottoms up to 500 meters deep, where he hunts small fish, squid and crustaceans, although it has also been observed to feed on dead animals.
Diplodus vulgaris
©João Pedro Silva
The two banded sea bream is easily found in rocky reefs near the coast, where it feeds on crustaceans, worms and molluscs. It reaches sexual maturity at the age of two or 17 cm in length. It’s a commercially valued fish.
Leodice torquata
©Áthila Bertoncini
This carnivorous bristle worm feeds on other small invertebrates that it captures with its jaws. It lives in shallow waters, under rocks or amongst the gravel. During mating, the females release pheromones that attract the males.
Sepia officinallis
©Emanuel Gonçalves
The cuttlefish skin has specialized cells that allows it to quickly change texture and colour and thus providing an excellent camouflage.
Pentapora foliacea
©Rui Guerra
This bryozoan is actually a colony of many small individuals. It grows on rocky bottoms exposed to currents and can be found on small stones in coarse sand areas. It is the largest bryozoan on the Portuguese coast.
Thecacera pennigera
©João Pedro Silva
This nudibranch, or sea slug, is found on rocky bottoms or on human origin structures colonized by bryozoans (tiny colonial animals), from which it feeds and where it lays its eggs.
Aplysina aerophoba
©João Pedro Silva
The yellow tube sponge forms tubular masses that measure up to 10 cm in height and 2 cm in diameter with a rubbery texture. It has a strong yellow color, but if removed from water it quickly turns dark blue and black.
Phoronis hippocrepia
©João Pedro Silva
The West Atlantic white phoronid is a small worm that lives in encrusting tubes in several types of substrates, from wood pieces, coral skeletons and shells to rocks and coralline algae, in light shaded areas. When it feels disturbed, the animal quickly retracts into the tube.
Tritonia hombergii
©João Pedro Silva
This is one of the largest sea slugs on the Portuguese coast, reaching 20 cm in length. It lives on rocky bottoms, near the soft corals from which it feeds. When disturbed it can secrete an irritant substance.
Symphodus bailloni
©João Pedro Silva
During the breeding season, the Baillon’s wrasse’s males build seaweed nests in rocky holes, where the females lay the eggs, protecting them until hatching.
Trapania pallida
©João Pedro Silva
This small nudibranch, or sea slug, can reach 17 mm in size. It is found in rocky reefs covered with sponges and sea squirts, where it can find the small animals from which it feeds.
Spurilla neapolitana
©João Pedro Silva
This sea slug lives under rocks in the seashore, feeding on several anemones. The appendages on its back may keep the stinging cells and symbiotic microalgae of the anemone’s tentacles.
Trisopterus luscus
©Emanuel Gonçalves
For a long time, the pouting had no great commercial interest and was part of the accidental catches of other fisheries. With population decreases of other fish, its consumption has been raising as a food item and in other products processing.
Eunicella cavolini
©João Pedro Silva
The yellow sea fan is a coral colony, classified as an endangered species in regarding its conservation status. It is quite vulnerable to some fishing gear since it has a slow growth, around 1 and 2 cm per year. It is found over rocky bottoms.
Symphodus cinereus
©Rui Guerra
The grey wrasse dwells in shallow areas of sandy bottoms and seagrass meadows such as estuaries and lagoon systems. It feeds on worms and small crustaceans, which it sometimes captures when they are dug up by other animals.
Zeugopterus regius
©João Pedro Silva
The topknot usually lives on rocky bottoms, and less often on thicker sand bottoms. It feeds on small fish and invertebrates.
Aiptasia couchii
©Emanuel Gonçalves
The trumpet anemone owes its name to its body shape, resembling a horn. It usually lives in rocky bottoms, sheltered from wave action, often in large numbers. This anemone captures its prey thanks to tentacles covered with stinging cells.
Gymnangium montagui
©Emanuel Gonçalves
The yellow feathers are a colony of hydrozoans, small polyp animals that grow in feather-like structures. It prefers sheltered and shallow areas, growing on rocks, shells or algae.
Epizoanthus couchii
©João Pedro Silva
This encrusting anemone grows in colonies on rocks or shells, in moderate water flow places, sometimes covered with sediments. When they feel threatened, polyps quickly retract the tentacles into their body.
Piseinotecus sphaeriferus
©João Pedro Silva
This small nudibranch rarely exceeds 6 mm in size. It lives on algae and seagrasses, where it feeds on tiny animals that grow on these.
Berthellina edwardsii
©João Pedro Silva
This sea slug can grow over 50 mm in length. It has nocturnal habits, and it is often found during the day under rocks and in crevices at low depths. Its eggs are laid in ribbon shaped spirals.
Lysmata seticaudata
©João Pedro Silva
The Mediterranean cleaner shrimp usually lives in rock crevices and holes, where it provides cleaning services to fish. It has some commercial interest, especially for aquariums, given its appetite to feed on anemone species that become pests.
Cratena peregrina
©João Pedro Silva
The pilgrim hervia is a sea slug that reaches 50 mm in size. It lives on rocky bottoms where it feeds on small colonial animals similar to anemones. The appendages’ colour on its back changes depending on the type of prey.
Zeugopterus punctatus
©João Pedro Silva
Unlike most flatfish, the topknot prefers rocky bottoms covered with algae rather than sand, where it is perfectly camouflaged and awaits its prey: small fish and crustaceans.
Onchidella celtica
©Pedro Silva
Although known as the celtic sea slug, this animal is closely related to terrestrial slugs, sharing with them the lung respiration. It is found in rocks in the seashore, where it feeds on algae.
Phycis phycis
©João Pedro Silva
The larger forkbeard is a fish with nocturnal habits, hiding in caves and holes in rocks during the day. It usually lives near rocky, sandy and muddy, where it feeds on small fish and several invertebrates.
Rhizostoma sp.
©Luís Quinta
This jellyfish is followed by horse mackerel juveniles that feed on small planktonic animals captured by the tentacles of the jellyfish, also benefiting from protection against larger predators.
Pollicipes pollicipes
©João Pedro Silva
The rock goose barnacle belongs to a group of crustaceans that live attached to rocks in wave and tide exposed areas. It feeds on suspended organisms that it captures with its cirri. It has a high commercial value and it only is harvested manually.
Eunicella verrucosa
©Rui Guerra
The common sea fan is classified as a vulnerable species, being the target of several studies and attempts to transplant it to areas where it was once common, but became scarce due to its slow growth and human impacts such as the use of trawl nets.
Octopus vulgaris
©Emanuel Gonçalves
Several behaviour studies have been conducted with the common octopus, which demonstrates that it has above-average intelligence, it can recognize shapes and sizes of objects, as well as unmatched learning ability.
Tursiops truncatus
©Luís Quinta
The common bottlenose dolphin can be found in all oceanic regions except for the polar ones. It can form groups (called pods) that remain in the same area, as is the case of the Sado estuary community with about 25 animals, and other communities in the nearby coastal zone.
Stolonica socialis
©João Pedro Silva
This sea squirt can form colonies of many individuals connected by the base, in areas exposed to currents, on rocks and stones sometimes partially covered with sand. It feeds on plankton that filters inside its body.
Phallusia mammillata
©João Pedro Silva
This white sea squirt is found in sheltered places with slow water movement and on rocks and stones, usually near muddy bottoms. It feeds by filtering planktonic microorganisms.
Calma glaucoides
©João Pedro Silva
This sea slug feeds on fish eggs, spending its adulthood always close to the spawn. The body colour varies according to the fish to which the eggs belong and the marks on the back improve the camouflage.
Anthias anthias
©Áthila Bertoncini
The swallowtail sea perch lives in groups next to caves and rock formations. These groups are usually formed by several females and only one male. If there is not a male in the group, the larger female undergoes a sex change, becoming the group dominant male.
Geitodoris planata
©João Pedro Silva
This nudibranch (animals belonging to the sea slug’s group) can reach 60 mm in length. It lives under rocks at low depths, where it feeds on encrusting sponges. It has acid-producing glands on the body.
Sargassum sp.
©João Pedro Silva
Some species of sargassum, or gulfweed, have air bubbles, which keep the algae to float, improving light exposure. They can form large algae patches, such as in the Sargassum Sea, becoming a unique and very important habitat for biodiversity.
Trisopterus luscus
©Emanuel Gonçalves
The pouting forms shoals next to rocky reefs, where juveniles are found at low depths and adults up to 300 meters. It feeds on worms, crustaceans and small fish and is an important prey for other predatory fish such as cod.
Prionace glauca
©Luís Quinta
The blue shark can grow over 3 meters in length, and females are larger than males. It is an endangered species due to overfishing for human consumption, especially the fins. It can give birth to over a hundred pups at once.
Necora puber
©Luís Quinta
The velvet swimming crab is common in rocky reefs, where it feeds on brown algae, bivalves and other crustaceans. It is commercially valuable, as it is a very appreciated seafood.
Palinurus elephas
©Emanuel Gonçalves
The spiny lobster is a high commercial value crustacean, and many of its populations are threatened by overfishing for human consumption. Therefore it is a species classified as vulnerable as to its conservation status.
Pomatoschistus sp.
©Emanuel Gonçalves
This small goby reaches a maximum length of 11 cm and is normally found over sandy bottoms, feeding on small invertebrates. It is believed that it may live up to one year.
Filograna implexa
©João Pedro Silva
The filigree worm forms an intricate network of tubes, where several individuals live. It grows in rock crevices, stones, shells, sand and even over other organisms, at low depth zones.
Lepadogaster lepadogaster
©Luís Quinta
The shore clingfish’s pelvic fins are modified into a suction disk that enables it to attach to rock surfaces or stones near the water surface, where it feeds on debris.
Phyllodoce laminosa
©João Pedro Silva
This worm lives in the seashore, under stones, in rock crevices or between mussel communities. It can also be found on rocky bottoms or covered with stones and shells.
Anemonia viridis
©Emanuel Gonçalves
The snakelocks anemone is one of the most common species of these animals on the Portuguese coast. It lives on rocks at low depths, where it can reach large numbers, as it reproduces easily by dividing the body, giving rise to clones of itself.
Bonellia viridis
©João Pedro Silva
The green spoonworm lives in rock crevices or abandoned burrows of other animals, where only its long proboscis (mouth) is visible. The male is about a hundred times smaller than the female and lives over or inside it, with the sole function of fertilizing the eggs.
Simnia spelta
©João Pedro Silva
This small sea snail is often found on different sea fans, from which it feeds and where it lays its eggs, grouped in several gelatinous pouches.
Corynactis viridis
©Luís Quinta
The jewel anemone gets its name from the bright and diverse colours, with the tentacles usually contrasting with the body colour. It is a small anemone, not larger than 10 mm, and prefers to live in places with moderate water flow such as vertical rocky faces.
Parazoanthus axinellae
©João Pedro Silva
The yellow encrusting anemone can form dense colonies on rocky reefs, often over encrusting red algae, sponges, shells, and worm tubes. It feeds on planktonic organisms that it captures with the tentacles.
Ciona edwardsi
©Ana Castanheira
The yellow sea squirt is a solitary animal that can reach 20 cm in size. Like the other sea squirts, it feeds by filtering water that enters its body by the inhalant siphon, travels through the digestive system and exits by the exhaling siphon.
Elysia viridis
©João Pedro Silva
This sap-sucking slug is found in shallow places, over green algae, especially on the green sea forks. In addition to consuming the algae, it can retain the chloroplasts in its body and keep them functional, contributing to the diet of the slug.
Pagurus prideaux
©João Pedro Silva
The Prideaux’s hermit crab lives on gravel, sand and mud bottoms at low depth. It is quite common to find a particular species of anemone on its shell, protecting the hermit crab in exchange for food scraps.
Epinephelus marginatus
©Emanuel Gonçalves
The dusky grouper is one of the most emblematic species of Portuguese waters. Overfishing is one major problem, amongst others, that led to populations decreases, classifying this fish as a vulnerable species. It lives in areas of rocky reefs up to 300 meters.
Antedon bifida
©João Pedro Silva
The rosy feather-star is a relative of the sea urchins and starfish. It lives on the seabed, although it can move both in protected and current-exposed areas. It feeds on suspended debris and plankton that are trapped by its feather shaped arms.
Lineus longissimus
©João Pedro Silva
This bootlace worm is considered the longest animal in the world, measuring up to 30 meters! It is found at low depths, on the sand or under rocks. Recently it has been discovered that it produces a strong toxin with potential use as a pesticide.
Octopus vulgaris
©Emanuel Gonçalves
When it feels threatened, the common octopus can escape by generating jets of water through a siphon. Often in these jets, it also releases a black ink to confuse and diminish the sight of its predator.
Processa macrophthalma
©João Pedro Silva
This small nocturnal shrimp is found at low depths in light sheltered places or among seagrasses.
Ectopleura larynx
©João Pedro Silva
The ringed tubularian is a colonial hydrozoan, found at low depths on rocks, algae and also in human origin structures, such as boat hulls. Polyps have a great regeneration ability.
Galathea squamifera
©João Pedro Silva
This squat lobster has nocturnal habits, hiding under stones and in rock crevices during the day, coming out at night to hunt mainly for small fishes. It can be found from shallow water down to 180 meters deep.
Polycitor crystallinus
©João Pedro Silva
This sea squirt grows in colonies up to twenty individuals, in crevices and other rocky sites. It feeds by filtering suspended particles and planktonic organisms from the water.
Sabella spallanzani
©Emanuel Gonçalves
Although common and native to our waters, the Mediterranean fan worm has become invasive in other countries such as Australia, where it damages several bivalve’s farming. It outcompetes these animals for food: planktonic microorganisms that are filtered from the water.
Nausithoe punctata
©João Pedro Silva
In its life cycle, this small crown jellyfish has a polyp larval stage, that lives attached to different substrates or even other animals. It later turns into a jellyfish, and during adulthood, it is found swimming in the water column.
Oedalechilus labeo
©Rui Guerra
The boxlip mullet is found near the coast and at rivers mouth. It feeds on debris and small plankton animals.
Sphaerechinus granularis
©Emanuel Gonçalves
This sea urchin often covers itself with algae or shell fragments. It feeds on various algae and debris that scrapes with its specialized mouthpiece, called "Aristotle’s lantern". Its gonads are sought after as a delicacy.
Acanthochitona fascicularis
©João Pedro Silva
The chitons are a group of exclusively marine molluscs. Its shell consists of 8 articulated plates or valves, overlapped at the edges. This velvety mail chiton lives on rocky bottoms, where it grazes on encrusting and filamentous algae.
Trivia monacha
©João Pedro Silva
This small sea snail, commonly known as trivia, lives on rocky bottoms and under rocks at low depths, next to colonies of sea squirts from which it feeds.
Clavularia crassa
©Emanuel Gonçalves
The translucent body of this soft coral allows us to observe its interior. During the breeding season, the fertilized eggs are kept outside the body until the larvae hatch and disperse in the water. Its conservation status is of little concern.
Doto floridicola
©João Pedro Silva
This sea slug, or nudibranch, lives exclusively on only one species of hydrozoan (tiny colonial animals), from which it also feeds and where it lays its white eggs in a zigzag pattern.
Parablennius pilicornis
©Emanuel Gonçalves
This variable blenny dwells on rocky reefs at low depth, usually in crevices or small holes in the rocks. After mating, the males protect the eggs until they hatch.
Solea senegalensis
©Áthila Bertoncini
The Senegal sole lives on sandy or muddy bottoms, from shallow waters down to 100 m deep. It feeds on worms, bivalves and crustaceans. It is a high commercial value fish and in Portugal it is also bred in aquaculture.
Felimida luteorosea
©João Pedro Silva
This nudibranch - an animal belonging to the sea slug’s group - can reach 50 mm in length. It lives on rocky bottoms, where it feeds on two sponges species.
Myxicola infundibulum
©João Pedro Silva
Apart from the tentacles, the sand-fan worm lives in an almost buried tube in sand or mud. When disturbed, it quickly withdraws into the tube. It can withstand different salinity levels and even be found in saltmarshes.
Felimare fontandraui
©João Pedro Silva
This sea slug can reach 40 mm in length but is usually smaller. It is found in dimly lit places of rocky bottoms, where it feeds on sponges.
Oscarella lobularis
©Emanuel Gonçalves
This encrusting sponge forms colonies on rocks, stones or large algae, such as kelp. It has a gelatinous texture and its surface is velvety. It is found in low-depth and seashores.
Gobius cruentatus
©Emanuel Gonçalves
The red-mouthed goby can reach 18 cm in length and is found at low depths, on rocky or sandy bottoms and seagrasses meadows. It is a low-value fish but quite enjoyed in some regions.
Trivia arctica
©João Pedro Silva
This small gastropod mollusc, also known as ribbed trivia, lives on rocky bottoms next to colonies of sea squirts from which it feeds. Their shells have been used as ornaments since prehistory.
Capellinia doriae
©João Pedro Silva
Small nudibranch or sea slug, that can reach 12 mm in length. It is found on rocky bottoms, where hydrozoans (small colonial animals) from which it feeds are abundant.
Raja undulata
©Inês Sousa
Between March and September, the undulate ray lays its eggs in sandy or muddy areas. These are bag-shaped with hooks in the corners and are commonly called mermaid’s purse.
Dictyota cyanoloma
©Rui Guerra
The doubling weed is a brown seaweed increasingly common in Portuguese waters. It is thought to be originally from Australia and has been dispersed from the Mediterranean. It contains several compounds that are being studied to assess their use by man.
Caryophyllia smithii
©João Pedro Silva
The Devonshire cup-coral has a calcified exoskeleton and a nearly transparent body, due to the lack of photosynthetic microorganisms that usually live associated within the coral and are responsible for its colouration.
Symphodus roissali
©João Pedro Silva
The five-spotted wrasse is found on rocky reefs covered with algae and on seagrass meadows, where it feeds on worms, molluscs, crustaceans and sea urchins. It has some commercial value, specifically as an ornamental species.
Saccorhiza polyschides
©Emanuel Gonçalves
When at high densities, the furbelows and other kelp act as marine forests, providing a large increase in local biodiversity.
Limaria hians
©João Pedro Silva
The gapping fileclam can be found on sand, shell fragments and stones, where it feeds on plankton that it filters from water. When threatened, it can move rapidly through jets of water created by the shells’ movement.
Chelidonichthys lastoviza
©João Pedro Silva
The streaked gurnard can be found on rocky and sandy bottoms. It feeds on crustaceans, particularly buried crabs, which it detects thanks to the spines of the pelvic fins that function as sensory organs.
Balaenoptera acutorostrata
©Luís Quinta
The minke whale is one of the smallest whales, only reaching 10 m long. Instead of teeth it has baleens, and so it feeds on small crustaceans and fish. This species can be found in all oceans, despite being classified as vulnerable.
Saccorhiza polyschides
©Emanuel Gonçalves
This seaweed’s blades have the same functions of plant leaves. However, in the marine environment, these surfaces are often colonized by other organisms, from bacteria to small colonial animals and even other algae.
Limacia clavigera
©João Pedro Silva
The orange-clubbed sea slug can reach 20 mm in size, although it is more common around 10 mm. It dwells on rocky bottoms, where it feeds on different species of bryozoans (tiny colonial animals).
Antiopella cristata
©João Pedro Silva
The crystal sea slug has a translucent body, covered with numerous appendages. Its colour rages from beige to yellow and it can reach 50 mm in length. It feeds on bryozoans, that are tiny colonial animals, often in poorly illuminated areas.
Dendrodoris grandiflora
©João Pedro Silva
The nudibranchs are a group within the sea slugs. Its name derives from the fact that the gills are located outside the body, usually in the rear end of the back. This particular sea slug lives at low depths and under rocks.
Platydoris argo
©João Pedro Silva
This is one of the largest nudibranchs - animals belonging to the sea slugs group - that can be observed on the Portuguese coast. It reaches 10 cm in size and lives on rocky bottoms, where it feeds on sponges.
Tritonia nilsodhneri
©João Pedro Silva
This is a hard to observe sea slug, due to its camouflage and sea fan’s mimicry, from which it feeds. It reaches 30 mm in length and its eggs are laid in spirals wrapped in the sea fan’s branches.
Cereus pedunculatus
©João Pedro Silva
This daisy anemone has over 500 tentacles – up to 1000! - which are usually the visible part of the animal. The rest of the body is hidden in crevices and holes on rocks or sand. If it feels threatened or disturbed, it recoils the tentacles into its the body.
Entelurus aequoreus
©João Pedro Silva
The snake pipefish is the largest of its group found in European waters, reaching 60 cm. It lives in seagrasses meadows and kelp forests in coastal areas. However, it can also be found further away from the coast, unlike other pipefish.
Prostheceraeus moseleyi
©João Pedro Silva
This flatworm feeds on sea squirts that it finds on rocky bottoms, at low depths. The colour patterns of this worm mimic that of some nudibranchs that predators recognize as toxic or foul-tasting.
Asparagopsis taxiformis
©Áthila Bertoncini
Despite being common on the coast of Arrábida, the "harpoon seweed" is an exotic species in our waters. When added to the diet of ruminant animals, it enables the reduction of over 90% of the methane emissions this type of cattle emits.
Taurulus bubalis
©João Pedro Silva
The sea scorpion lives on rocky bottoms covered with algae in the seashore. It is a voracious predator, feeding on a wide variety of animals that approach it without detecting it, thanks to its camouflage.
Clavelina lepadiformis
©João Pedro Silva
The light bulb sea squirt grows in colonies that can be found attached to rocks, stones, seagrasses and artificial structures. Like other animals in this group, it feeds on planktonic microorganisms that it filters from the water.
Diaphorodoris alba
©João Pedro Silva
This sea slug, or nudibranch, is often found in rocky bottoms and dimly lit areas, where it feeds on bryozoans (tiny colonial animals). It hardly exceeds 10 mm in size.
Maja brachydactyla
©João Pedro Silva
The Atlantic spider crab lives on rocky and sandy bottoms, where it feeds on small bivalves, sea urchins, starfish and algae. The carapace is usually covered with small organisms and algae, which helps its camouflage. It has a high commercial value.
Saccorhiza polyschides
©Emanuel Gonçalves
When at high densities, the furbelows and other kelp act as marine forests, providing a large increase in local biodiversity.
Eunice sp.
©João Pedro Silva
This worm lives buried in sandy and muddy bottoms or between rocks, where it waits for its prey that it detects with the help of five antennae on top of its head. It usually feeds on small fish, quickly grabbing them with its jaws.
Saccorhiza polyschides
©Emanuel Gonçalves
The furbelows attach itself to rocks or stones through a hollow structure. This acts as a shelter for diverse organisms such as small crustaceans and molluscs that protect themselves from predators and turbulent conditions.
Zostera marina
©Emanuel Gonçalves
The eelgrass is a flowering plant of great ecological importance, because it can form prairies that provide shelter and act as a nursery for a vast number of organisms. It grows below the tidal zone on mud or sandy bottoms.
Callionymus lyra
©João Pedro Silva
The common dragonet lives on sandy and muddy bottoms, where it feeds on small worms and crustaceans. Males are quite territorial and have colorful dorsal and pectoral fins, which they exhibit during a complex mating ritual.
Cystoseira usneoides
©Emanuel Gonçalves
The bushy bladder-chain wrack is a highly branched brown algae, found attached to rocks thanks to a disk-like structure. It forms dense communities that act as a shelter for many other organisms
Spirastrella cunctatrix
©João Pedro Silva
The orange encrusting sponge, quite common in some places, grows on rocks and stones in light sheltered zones such as caves or rocky overhangs. Like other sponges, it feeds by filtering organic particles and planktonic microorganisms.
Codium tomentosum
©Áthila Bertoncini
The green sea fork is a branched spongy seaweed with velvety texture found in tidal pools, attached to rocky bottoms. Several compounds extracted from these algae are widely used in cosmetic products, due to their moisturizing properties.
Crimora papillata
©João Pedro Silva
This sea slug prefers dimly lit places on rocky bottoms, such as crevices or small holes. It feeds on bryozoans, tiny colonial animals. Although it can grow above 30 mm, it rarely exceeds 20 mm.
Ophioderma longicaudum
©João Pedro Silva
This smooth brittle star lives on rocky or sandy bottoms, rich in organic matter, from which it feeds. Like other animals in this group, if parts of the body are injured or even severed, it can fully regenerate.
Myriapora truncata
©João Pedro Silva
The false coral is a bryozoan. They form colonies of small individuals called zooids, different from coral polyps and other similar animals. They grow in cave crevices and when removed from the water, they quickly lose the colour.
Trinchesia cuanensis
©João Pedro Silva
This small nudibranch, or sea slug, reaches 15 mm in size. It is found in rocky bottoms and shallow areas, next to the hydrozoans (small colonial animals) from which it feeds.
Caprellidae sp.
©João Pedro Silva
The skeleton shrimp usually lives associated with other animals, such as sponges and anemones, or plants such as the eelgrass, in shallow areas. They are omnivores, feeding on microorganisms, debris and other crustaceans.
Rhopalaea neapolitana
©João Pedro Silva
Solitary sea squirt that grows on rocky bottoms. It feeds on suspended particles and planktonic organisms that it captures with a mucus net that it produces.
Trinchesia genovae
©João Pedro Silva
Small nudibranch, or sea slug, which reaches a maximum of 10 mm. It is found in dimly lit areas of rocky reefs, next to the hydrozoans (small colonial animals), from which it feeds and where it lays its eggs.
Pagurus anachoretus
©João Pedro Silva
Like all hermit crabs, some of its body is soft and unprotected by the carapace, hence the use of empty sea snail shells, that must be changed during their growth. The striped hermit crab lives on rocky bottoms.
Larus michahellis
©João T. Tavares
In recent years, the yellow-legged gull’s population has been increasing caused by the occupation of urban areas and human origin structures. It has a diverse diet, from fish and crabs to waste from human activities.
Raja undulata
©Inês Sousa
The undulate ray is another example of an endangered species due to overfishing. It lives on sandy or muddy bottoms, where it feeds on a wide variety of animals, from crustaceans to molluscs and other fish.
Tethya citrina
©Áthila Bertoncini
Also called sea lemon, this sponge has shades between yellow and orange. It usually has a globular shape and a warty texture. It reaches 6 cm in diameter and is easily found on rocky bottoms at low depth.
Haliotis tuberculata
©Luís Quinta
The European abalone is a commercial interest gastropod, although it is believed that its populations are being overexploited. It is found at low depth rocky bottoms, usually under stones, where it feeds on algae.
Anemonia viridis
©Emanuel Gonçalves
The snakelocks anemone is easily found in well-lit places such as tidal pools and other low depth areas, attached to rocks and stones. Sometimes it can also be found in seagrass and in algae leaves. In some places it is appreciated as a delicacy.
Symphodus melops
©Rui Guerra
The corkwing wrasse dwells on rocky bottoms covered with algae and in seagrass meadows, feeding on worms, small molluscs and crustaceans. This wrasse’s males build seaweed nests where the females lay the eggs, protecting them until they hatch.
Gobius paganellus
©João Pedro Silva
As the name implies, the rock goby lives in rocky areas at low depths, and it is common to find it in tidal pools between algae. It feeds on a wide variety of small crustaceans and fish, but also algae.
Parablennius gattorugine
©João Pedro Silva
The tompot blenny can be found in shallow waters, usually in crevices in rocky reefs, but also among algae and seagrasses. They are territorial fish and the male protects the eggs laid by several females until they hatch.
Aaptos papillata
©Nuno Vasco Rodrigues
Like most of other sponge species, the pink-tit sponge it is a filter animal, feeding on bacteria and particles that are trapped inside its body. It grows in a domed shape and is usually found covered by sand and debris, except for the "nipples" on its body surface.
Labrus bergylta
©Emanuel Gonçalves
During the breeding season, the ballan wrasse’s male builds a nest of algae in rock crevices where one or more females lay their eggs. They all are born females, changing sex between 4 and 14 years.
Sabella spallanzani
©Luís Quinta
Thanks to its ability to filter and accumulate bacteria in the body, the Mediterranean fan worm is considered as a water quality bioindicator. Some studies are also being conducted that aim to assess its potential for wastewater bioremediation.
Paralcyonium spinulosum
©João Pedro Silva
The grey sea finger is a soft coral, so it does not produce a calcified structure. It grows in colonies and each individual, or polyp, feeds on suspended particles and plankton that captures with the tentacles.
Codium vermilara
©Rui Guerra
The green sea forks usually live attached to rocks or stones, in tidal pools or low-depth areas. As in similar species, the different chemical compounds produced by this algae are increasingly studied and used by man.
Edmundsella pedata
©João Pedro Silva
This nudibranch, or sea slug, can be found over rocky bottoms, feeding on several species of hydrozoans (small colonial animals), where it also lays its eggs. It reaches 30 mm in length.
Eunicella gazella
©João Pedro Silva
Like other sea fans, these coral colonies share the same fan-like shape. It is found in rocky reefs from low depths up to 150 meters.
Pachycerianthus sp.
©Ana Castanheira
The tube anemone lives on sandy and muddy bottoms. The tube has a pointed shape on its lower part, allowing the animal to bury itself if it feels disturbed. It may have over 200 tentacles that it uses to hunt small prey.
Discodoris rosi
©João Pedro Silva
This nudibranch, or sea slug, is often confused with the encrusting sponges from which it feeds. This camouflage makes it difficult to observe. It lives on rocky bottoms and can measure up to 25 mm in length.
Monoplex parthenopeus
©João Pedro Silva
The Neapolitan triton lives at low depths on rocky bottoms, where it feeds on other molluscs that paralyzes thanks to toxins it secretes from the mouth.
Marionia blainvillea
©João Pedro Silva
This nudibranch is often found in rock walls, where there is a large concentration of sea fans and other similar preys. The juveniles are whitish, turning to red or orange as adults.
Lepidorhombus whiffiagonis
©Rui Guerra
The megrim can be found at depths up to 800 m and on sandy or muddy bottoms, where it feeds on small fish, squid and crustaceans. It is fished with bottom trawler nets.
Yungia aurantiaca
©João Pedro Silva
The orange flatworm dwells on rocky bottoms at low depth, where it feeds on sea squirts and other organisms. Its garish colour serves as a warning to predators, especially fish, about its toxicity or unpleasant taste.
Astropecten aranciacus
©Rui Guerra
The red comb star usually lives buried in mud, sand or gravel bottoms. It is easier to see it at the end of the day and at night, when it is more active and looking for molluscs that are the base of its diet.
Syngnathus acus
©Emanuel Gonçalves
The greater pipefish lives in coastal areas usually amongst kelp and seagrass prairies. It feeds on small crustaceans such as shrimps and others, as well as larvae and juveniles of other fish.
Thorogobius ephippiatus
©João Pedro Silva
This leopard-spotted gobi dwells in sandy areas of rocky reefs, small caves and holes beneath rocks. It feeds essentially on worms and small crustaceans.
Haliotis tuberculata
©João Pedro Silva
The European abalone is found on rocky bottoms, usually under stones, at low depth. It feeds on algae, preferring the red ones. When it feels threatened, it retracts inside the shell and stays firmly attached to the rock.
Doto pinnatifida
©João Pedro Silva
Sea slug, or nudibranch, which lives exclusively on only one species of hydrozoan (tiny colonial animals), from which it also feeds. It reaches a maximum of 30 mm in length, although not often.
Arnoglossus thori
©Emanuel Gonçalves
The Thor’s scaldfish has a curious adaptation for capturing preys. One of the dorsal fin rays acts as a bait for small fish and crustaceans, luring them to approach the mouth of the scaldfish, where they turn in to its meal.
Chelon ramada
©Rui Guerra
The thin-lipped grey mullet feeds on debris, algae and small planktonic organisms. it lives in coastal areas and may have commercial value if fished in clean waters distant from human activities.
Pollachius pollachius
©João Pedro Silva
During her youth phase, the pollack remains at low depths near shore, migrating to deeper waters as an adult. It lives next to rocky bottoms, where it feeds on other fish. It is marketed as a cod substitute.
Actinothoe sphyrodeta
©João Pedro Silva
The sandalled anemone usually lives on hard and rocky bottoms, over flat surfaces. Its body is about 2 cm long and can have up to 120 tentacles. It reproduces by fission, separating from the base and giving rise to two individuals.
Arnoglossus thori
©Emanuel Gonçalves
Thanks to its body shape and colour, the Thor’s scaldfish can easily conceal itself over the sea floor, attracting its prey with a "bait", which is nothing more than a modified ray of the dorsal fin.
Hippocampus guttulatus
©Diogo Paulo
Like most seahorses, during the mating season, the female transfers the eggs into the male’s brood pouch, where they hatch and develop. When the small seahorses reach a certain size, the father expels them.
Ophiocomina nigra
©João Pedro Silva
Related to sea stars, this black brittle star lives in large numbers in places sheltered from light. It feeds on small invertebrates, algae debris, dead animals or suspended particles.
Felimare picta
©João Pedro Silva
This is the largest nudibranch (animals belonging to the sea slug’s group) reaching 200 mm in length. It is found in dimly lit places of rocky bottoms, where it feeds on sponges.
Aiptasia mutabilis
©Rui Guerra
Depending on the depth at which it is found, the trumpet anemone may establish symbiosis relationships with photosynthetic organisms, such as some microalgae. Therefore, when exposed to higher luminosity it tends to have a stronger brownish colour.
Lithophyllum stictaeforme
©Áthila Bertoncini
These red-encrusting algae are usually found in tidal pools. It has a calcareous structure that can help in habitat formation for other organisms.
Homarus gammarus
©João Pedro Silva
The European lobster is one of the most commercially valuable crustacean species. It normally lives in crevices and holes in rocks, but are also able to dig shelters on soft bottoms. It has nocturnal habits and has a very diverse diet.
Lepadogaster candolii
©João Pedro Silva
The clingfish exhibits a curious adaptation of the pelvic fins into a suction disc that allows it to attach to stones, rocks and seagrasses. It feeds on small invertebrates and can act as a cleaning fish for larger animals such as groupers.
Halocynthia papillosa
©João Pedro Silva
This red sea squirt lives on rocky or gravel bottoms with shell and coral fragments. It feeds on suspended particles that it filters inside its body.
Leptopsammia pruvoti
©João Pedro Silva
This sunset cup coral is often found in sheltered rocky zones such as caves, overhangs or rock crevices. It is a solitary animal, although sometimes it may be observed in large numbers creating pseudo-colonies.
Eunicella verrucosa
©Alexandra Huth
The common sea fan, like other species of the same group, has a slow growth (between 1 to 5 cm per year), which contributes to its conservation status as a vulnerable species. It grows over rocky bottoms with moderate water flow.
Diaphorodoris papillata
©João Pedro Silva
This sea slug, or nudibranch, reaches 10 mm in length, although it is usually smaller. It is often found on rocky bottoms of dimly lit areas, where it feeds on bryozoans (tiny colonial animals).
Felimare villafranca
©Emanuel Gonçalves
This sea slug can reach 50 mm in length. It does not undergo a larval phase, but instead, small juveniles hatch right from the eggs. It lives on rocky bottoms, where it feeds on sponges.
Alcyonium acaule
©João Pedro Silva
The sea finger is actually a colony formed by several individuals or polyps, which grows in a finger shape, reaching 20 cm in height. It is found in shaded areas, avoiding direct sunlight, like rocky overhangs and caves.
Marthasterias glacialis
©Emanuel Gonçalves
The spiny sea star is one of the largest species of these animals on the Portuguese coast. It lives in different types of sea beds, from muddy to rocky ones near the surface. It feeds on molluscs, sea urchins and other sea stars.
Luisella babai
©João Pedro Silva
The white flabellina is an easily observed nudibranch or sea slug, that can reach 60 mm in size. It feeds on several hydrozoans - small colonial animals similar to anemones - on rocky bottoms
Lima lima
©João Pedro Silva
The spiny fileclam lives both on rocky and coralline bottoms, as well as in seagrass meadows. It feeds on planktonic organisms and suspended matter that it filters from water.
Alcyonium digitatum
©João Pedro Silva
Like other false corals, the polyps of the dead man’s fingers feed by extending the tentacles and capturing suspended particles. During the summer, when the water temperature is higher, these animals can enter a dormancy state, retracting the polyps.
Aegires punctilucens
©João Pedro Silva
This small nudibranch, or sea slug, grows up to 20 mm and it is found in rocky bottoms where it feeds on a specific sponge species. The numerous appendages that cover its body give it an excellent camouflage.
Aeolidiella alderi
©João Pedro Silva
This sea slug grows up to 14 mm and can be found in the seashore, where it feeds on a wide variety of anemones. Its body is orange, covered with appendages that may change colour depending on the ingested food.
Taínhas, Liças e Muges
©Emanuel Gonçalves
There are several species of grey mullets that are not always easy to distinguish. They usually live at low depths, along the coast and in river estuaries. It is common to observe them in human activity areas with polluted waters.
Eualus cranchii
©João Pedro Silva
This small shrimp, about 2 cm long, lives in low-depth areas, under rocks or in holes. It is also possible to find it among algae and seagrasses meadows.
Aplidium sp.
©João Pedro Silva
This is a species of colonial sea squirts, formed by several individuals with both sexes. After fertilization, the eggs are released to the water, hatching into a swimming larva that later on will attach to the substrate and turn into an adult.
Delphinus delphis
©Luís Quinta
This is the most common dolphin in Portuguese waters. Very sociable, the short-beaked common dolphin lives in groups that can reach 500 individuals that are known for its acrobatics and speed, reaching up to 60 km/h. It feeds on fish and cephalopods, especially squid.
Saccorhiza polyschides
©Luís Quinta
The furbelows is a large and fast-growing seaweed that may reach between 2 and 3 meters high. It attaches to the rocky substrate through a bulbous and hollow structure. Its dense settlements act as habitat for countless other species.
Balssia gasti
©João Pedro Silva
This small shrimp does not exceed 2 cm in size and lives in association with several species of sea fans, corals and sponges. It is hard to observe due to its camouflage, as it tends to have a similar colour to that of the animal where it lives in.
Bothus podas
©João Pedro Silva
The wide-eyed flounder lives on sand and gravel bottoms and is able to adapt its skin colour to the surrounding environment. It feeds on small fish, crustaceans and worms. It is classified as a protected species.
Mullus surmuletus
©Emanuel Gonçalves
The striped red mullet is a widely appreciated fish. It usually lives over sandy and muddy bottoms, where it captures its prey - worms, crustaceans and molluscs - located by two barbels on the lower jaw.
Anomia ephippium
©João Pedro Silva
The shape of the saddle oyster shell can be quite variable, as it tends to acquire the profile of the substrate where it lives, which can be either on stone, kelp or other animals’ shells. It lives from the tidal zone to low depths.
Holothuria arguinensis
©Emanuel Gonçalves
The sea cucumber is an animal that belongs to the same group of starfishes and sea urchins. This species lives on sandy and muddy bottoms and in seagrass meadows, where it feeds on organic matter and bacteria from sediments.
Acromegalomma vesiculosum
©João Pedro Silva
This tube worm reaches up to 12 cm in length and has about 50 tentacles, each with an “eye spot” on the tip, which enables it to be light sensitive. The tube is encrusted with sand and shell fragments, and most of it remains buried in the substrate.
Palinurus elephas
©Luís Quinta
The spiny lobster is more active at nighttime, leaving the small caves and holes where it inhabits to hunt for molluscs, sea stars, sea urchins and other crustaceans. It also feeds on dead animals.
Parablennius ruber
©João Pedro Silva
The portuguese blenny is found on rocky reefs at low depth, usually in crevices or small holes in the rocks. It feeds on a wide variety of animals such as anemones, molluscs, worms, crustaceans and even red algae.
Recife coberto de invertebrados
©Emanuel Gonçalves
The rocky reefs, quite common on the Portuguese coast, are home to a great diversity of organisms. From algae to fish, through the most assorted invertebrates, these places provide food, shelter, rest and breeding conditions.
Serpula vermicularis
©João Pedro Silva
Like other tubeworms, this one also feeds on planktonic organisms that it filters with feather-like tentacles. When it feels disturbed, it quickly withdraws the body into the tube.
Diplodus sargus
©Luís Quinta
Like other species of seabreams, the white seabream dwells preferably in areas of rocky reefs, being more abundant near the surf zone. It is an omnivorous fish, including in its diet crustaceans, molluscs, worms, corals and algae.
Calliactis parasitica
©João Pedro Silva
Despite the name, the parasitic anemone establishes beneficial relationships with hermit crabs, by attaching itself to their shells and protecting them against predators. When feeding, the crab throws pieces of food that the anemone collects and ingests.
Berghia coerulescens
©João Pedro Silva
This sea slug lives on rocky bottoms, where it feeds on anemones. It is a hermaphrodite species, laying its eggs in a spiral shape. Its bright colors usually act as a warning to predators, indicating its toxicity or foul taste.
Octopus vulgaris
©Emanuel Gonçalves
The common octopus has a great commercial value for the fishing sector in Portugal and is even exported to Japan. It is typically captured by traps such as pots. Several attempts are being made to produce it in aquaculture, but to no avail so far.
Echiichthys vipera
©Emanuel Gonçalves
The lesser weever lives on sandy and muddy bottoms, at low depths and often in the surf zone. It is usually buried, except for its mouth, eyes and the fist dorsal fin ray, waiting for its prey: small fish and crustaceans.
Sagartia elegans
©João Pedro Silva
The elegant anemone lives on rocky bottoms, in crevices or small holes. It is able to move, sometimes releasing fragments from its base that originates new individuals. It feeds on small invertebrates captured by its tentacles.
Solea solea
©João Pedro Silva
The common sole lives camouflaged in sandy and muddy bottoms. During the juvenile phase, it lives in coastal areas, migrating to deeper waters as an adult. It feeds on worms, molluscs and crustaceans. It is a fish of high commercial value, also produced in aquaculture.
Gobius xanthocephalus
©Emanuel Gonçalves
This yellow-headed goby lives in shallow water rocky places and seagrasses meadows. It grows up to 10 cm and feeds on small animals, especially crustaceans
Felimare cantabrica
©João Pedro Silva
This nudibranch (animals belonging to the sea slug’s group) can reach 50 mm in length. It lives on rocky bottoms, where it feeds on sponges. The eggs are white and laid in ribbon-shaped spirals.
Saccorhiza polyschides
©Carlos Franco
The furbelows is a kelp species with an annual life cycle. It typically starts growing in March and reaches its maximum size in September. During this period, it may grow more than 6 cm per week.
Clavularia crassa
©João Pedro Silva
This soft coral usually forms colonies up to fifty polyps, which grow in shallow areas on rocky or sandy bottoms. However, it can also be found alongside some seagrasses.
Sabella discifera
©João Pedro Silva
This spiral tubeworm is found attached to rocks, algae or sea fans. It feeds on organisms and suspended particles, which it filters from water thanks to its feather-shaped tentacles. When it feels threatened, it quickly withdraws for the tube interior.
Cuthona ocellata
©João Pedro Silva
This is a small sized sea slug, usually reaching 10 mm long. It lives on rocky bottoms, where it feeds on various species of hydrozoans - tiny animals that live in colonies.
Gobius gasteveni
©Emanuel Gonçalves
Steven’s goby is usually found on muddy sand bottoms with small stones or scattered rocks, usually between 30 and 250 meters deep.
Aporodoris millegrana
©João Pedro Silva
This nudibranch, which belongs to the group of sea slugs, can grow up to 30 mm in length. Its flattened body is usually brownish orange or purplish. It is found under rocks, at low depth, where it feeds on sponges.
Lepidonotus clava
©João Pedro Silva
This worm is found in the seashore in sandy or muddy bottoms, under rocks, among algae and on reefs formed by tubes of other worms.
Gobiusculus flavescens
©Ana Castanheira
Unlike other gobies, the two-spotted goby lives most of the time in schools away from the bottom. It prefers areas of algae and seagrasses but is also found in tidal pools. It feeds on planktonic organisms.
Polybius henslowii
©João Pedro Silva
This swimming crab sometimes forms numerous groups on the sea surface, truly becoming a feast to seabirds, turtles and fish. It feeds on squids, small fish, worms and other crabs.
Calonectris diomedea
©Luís Quinta
The Scopoli’s shearwater is a migrating bird that only breeds on islands and islets. It is easily observed from the coast during the warmer seasons. It has a very distinctive call. Currently, this bird is classified as a vulnerable species.
Scorpaena notata
©João Pedro Silva
The small rockfish dwells in crevices and rocky overhangs and can also be found on sand or mud bottoms. It feeds on small fish, crustaceans and other invertebrates. It has poison glands at the base of the dorsal fin rays.
Processa edulis
©João Pedro Silva
This small nocturnal shrimp is found at low depths in light sheltered places or among seagrasses.
Scorpaena porcus
©João Pedro Silva
The brown rockfish lives among rocks and algae, where it feeds on small fish, crustaceans and other invertebrates. Like other rockfish, the rays of the dorsal fin contain a painful poison.
Nereiphylla paretti
©João Pedro Silva
This is worm is a fast-moving predator with night habits, living between algae on rocky bottoms and spending most of the day in crevices or under rocks.
Symphodus roissali
©Emanuel Gonçalves
During the breeding season the five-spotted wrasse males build algae nests in rocky cavities, where the females lay the eggs, protecting them until hatching.
Eupolymnia nebulosa
©João Pedro Silva
The medusa worm lives in a tube buried in sand, mud or under rocks. It has numerous and long tentacles on its head, through which it feeds on small particles or debris of organic matter
Octopus vulgaris
©Emanuel Gonçalves
The common octopus is one of the most fascinating marine animals. It can change the colour and texture of its body becoming unnoticed in virtually any place. It is a voracious predator, feeding mainly on crabs and bivalves.
Inachus phalangium
©João Pedro Silva
The Mediterranean spider crab lives on rocky bottoms, usually associated with the snakelocks anemones, feeding on its food and mucus scraps. Its body may be covered with other organisms, such as sponges, which give it better camouflage.
Berthella plumula
©João Pedro Silva
The yellow-plumed sea slug is often found under rocks in the seashore or at low depth, feeding on colonial sponges and ascidians. Its skin has specialized glands that produce sulfuric acid which helps to protect the sea slug from predators.
Peixes de recife rochoso
©Emanuel Gonçalves
The rocky reefs, quite common on the Portuguese coast, are home to a great diversity of organisms. From algae to fish, through the most assorted invertebrates, these places provide food, shelter, rest and breeding conditions.
Hancockia uncinata
©João Pedro Silva
Small sea slug that reaches a maximum of 15 mm in length. It usually lives close to its food, the hydrozoans (small colonial invertebrates) that grow over algae or other animals.
Pomatoschistus pictus
©João Pedro Silva
The painted goby is a small fish that rarely exceeds 6 cm in size. It is found in shallow waters, on sandy or gravel bottoms. Juveniles are commonly found in tidal pools. It feeds on small crustaceans.
Zostera marina
©Rui Guerra
At the beginning of this century, the eelgrass meadows - which were once quite common - practically disappeared from the Arrábida Natural Park. In an effort to reintroduce this plant, transplants were performed, and today there is a small population next to the Coelhos’ beach.
Facelina auriculata
©João Pedro Silva
This nudibranch, or sea slug, grows up to 50 mm but is usually smaller. It lives over rocky bottoms at low depths and under rocks in the seashore. It feeds on several species of hydrozoans (small colonial animals).
Lanice conchilega
©Rui Guerra
Many worms live buried in the substrate, making tubes that include sand or shell fragments and extend above the sea bed.
Octopus vulgaris
©Luís Quinta
Reproduction marks the end of the common octopus’s life. Shortly after mating, the male dies, while the female lays up to half a million eggs and takes care of them until they hatch, dying afterwards.
Aiptasia couchii
©Emanuel Gonçalves
Although it can breed sexually, producing larvae that are dispersed in the water and then settle in another place, the trumpet anemone usually reproduces through simple body division, by releasing fragments which quickly originate a large number of clones.
Tritia reticulata
©Rui Guerra
Thie netted nasa can be found in sand and muddy bottoms at low depths. It tolerates low salinities allowing it to be present in estuaries. It has a keen sense of smell that allows it to detect the dead and decaying animals from which it feeds.
Ellisella paraplexauroides
©Armando Ribeiro
This gorgonian, also known as sea fan, can be found at depths up to 700 meters on rocky bottoms, where it is an important contributor to local biodiversity.
Sphaerechinus granularis
©Emanuel Gonçalves
The purlple sea urchin lives at low depths, in sheltered areas of rocky reefs or algae covered rocks, where it feeds. It is an animal quite predated by some starfish species and even humans in some places.
Peixes chatos
©Emanuel Gonçalves
Flatfish larvae are similar to other fish. As they grow, one eye migrates to the same side of the other, while the body acquires its characteristic shape. Their shape allows them to go unnoticed in the sand bottoms.
Paraflabellina ischitana
©João Pedro Silva
This nudibranch dwells in dimly lit areas of rocky bottoms, near the hydrozoans (small colonial invertebrates) from which it feeds. The appendages on its back are transparent, allowing to observe the colourful digestive gland.
Leptogorgia sarmentosa
©Luís Quinta
This sea fan colonies are either male or female. The sperm is released into the water and the eggs are fertilised inside the female colonies. When they hatch, the larvae are liberated into the water, remaining there for several weeks, until they settle on a suitable place and develop into polyps that will grow into new colonies.
Prostheceraeus giesbrechtii
©João Pedro Silva
This flatworm feeds on sea squirts that it finds on rocky bottoms at low depths. It is a hermaphrodite animal, each individual having organs of both sexes.
Chaetopleura angulata
©João Pedro Silva
This is the largest chiton found in Portuguese waters. It inhabits rocky and sandy zones at low depth. It feeds on algae that grow on stones, scraping them with its radula, a tongue-like structure with small teeth.
Rostanga rubra
©João Pedro Silva
This is a hard to observe nudibranch because its camouflage helps it to blend with the sponges from which it feeds. It is usually found close to these, on rocky bottoms. Although it is rare, it can measure more than 60 mm.
Trapania maculata
©João Pedro Silva
This small nudibranch, or sea slug, can reach 17 mm in size. It is found in rocky reefs covered with sponges and sea squirts, where it can find the small animals from which it feeds.
Jorunna tomentosa
©João Pedro Silva
This sea slug is difficult to observe due to the spotted patterns on its body that mimic the sponges from which it feeds. It lives in the proximity of these, on rocky bottoms and can reach 50 mm in size.
Diplodus cervinus
©Emanuel Gonçalves
The zebra seabream is a commercially valued fish, which contributes to the over-exploitation of its populations. While juveniles are common in seagrass meadows and low depth rocky areas, adults are found deeper.
Alicia mirabilis
©João Pedro Silva
The berried anemone is one of the most stinging anemones in the world. During the day it stays retracted with the tentacles inside the body, acquiring a shape that does not resemble an anemone. It expands at night, reaching 40 cm in height.
Pagurus cuanensis
©João Pedro Silva
The hairy hermit crab lives on different bottom types, where it feeds on algae, debris or other small invertebrates. As it grows, it needs to change the shell to suit its body.
Dondice banyulensis
©João Pedro Silva
This very colourful nudibranch grows to 70 mm. It lives on rocky bottoms, where it feeds on several species of hydrozoans (small colonial animals). Its eggs are white and laid in irregular spirals.
Pawsonia saxicola
©João Pedro Silva
The sea gherkin is a sea cucumber with very developed and branched mouth tentacles. It is found in rocky areas, under stones or in cracks in the rocks. It feeds on plankton that it captures with its tentacles
Leptogorgia sarmentosa
©Emanuel Gonçalves
Sea fans often form dense communities, and like coral reefs, contribute to greater local biodiversity, as they serve as habitat and shelter for several species.
Labrus bergylta
©Emanuel Gonçalves
The ballan wrasse lives in coastal waters and in rocky reefs covered with algae, where it feeds on crustaceans and molluscs. It has some commercial value as food and as an ornamental fish. It can live up to 18.
Sphaerococcus coronopifolius
©Áthila Bertoncini
This red seaweed is extremely branched and has a cartilaginous consistency. In recent years, several studies have been carried, discovering new chemical compounds, some with antibacterial and antitumoral properties.
Sepiola sp.
©Luís Quinta
This small bobtail squid has a light organ next to the gills, which houses bioluminescent bacteria. It dwells in sandy and muddy bottoms near rocky areas and is more active at night.
Cadlina pellucida
©João Pedro Silva
This small sea slug can reach 20 mm. Its translucent white body allows viscera observation. It lives on rocky bottoms, small cavities or on the sponges from which it feeds.
Serpula vermicularis
©Emanuel Gonçalves
This red tubeworm forms limestone tubes on rocks, stones, shells, boat hulls or other human origin structures. In some places, usually more sheltered, it can become very abundant and originate small reefs.
Doriopsilla pelseneeri
©João Pedro Silva
This sea slug or nudibranch has a rounded body covered with appendages. It can grow up to 40 mm in length and it feeds on sponges in rocky and dimly lit areas. On the Portuguese coast, it has a bright orange colouration.
Ciona intestinalis
©João Pedro Silva
This is a solitary sea squirt, although it may be found in large numbers. It can attach itself to a wide variety of substrates, from rocks to artificial structures such as piers and boats. It is considered an invasive species in some parts of the world.
Trinchesia morrowae
©João Pedro Silva
Small nudibranch, or sea slug, which reaches a maximum of 10 mm. It is found in dimly lit areas of rocky reefs, next to the hydrozoans (small colonial animals), from which it feeds and where it lays its eggs.
Halobatrachus didactylus
©Emanuel Gonçalves
The Lusitanian toadfish is an ambush predator, partially burying itself in sand or mud or hiding in rock crevices, where it waits for its prey: small crustaceans, molluscs and fish. It emits several characteristic sounds during the mating season.
Gobius niger
©João Pedro Silva
The black goby lives mainly on sandy or muddy bottoms, seagrasses or algae meadows, and is even found in estuaries and brackish water. It feeds on crustaceans, bivalves and small fish.
Dendrophyllia ramea
©Armando Ribeiro
The orange tree coral forms colonies with calcified structures of orange color, although their polyps are white. They can be found in caves and sheltered places at low depth, but also at several hundred meters depth over rocky bottoms.
Belone belone
©Rúben Fortuna
The garfish is an open ocean species, although it moves to shallower water to spawn. It feeds on small fish that it captures with a swift sideways movement of its long jaws equipped with small sharp teeth.
Sabella spallanzani
©Rui Guerra
This is one of the largest fan worms, a worm that forms mucus and sediment particles tubes. It grows in areas of slow currents, on rocks, artificial structures, in sand or mud. At the base of the tube, it is common for other organisms to grow.
Boops boops
©Rui Guerra
The bogue forms shoals that live near the seabed, approaching the surface at night. It feeds on small crustaceans and algae. It has a low commercial value, and much of its catch is destined for fishmeal production.
Charonia lampas
©João Pedro Silva
The knobbed triton is found on rocky and sandy bottoms, up to 700 m depth. It is a predatory sea snail that mainly captures bivalves, starfish and sea urchins. Its shell is usually covered with other organisms, such as coralline algae.
Prostheceraeus roseus
©João Pedro Silva
This flatworm feeds on sea squirts that it finds on rocky bottoms, at low depths. This a hermaphrodite invertebrate, where each individual bear both sexual organs.
Polycera faeroensis
©João Pedro Silva
This sea slug has an almost transparent body, which enables to observe some of the internal organs. It reaches 40 mm in length and lives on rocky bottoms, where it feeds on bryozoans (tiny colonial animals).
Sabella pavonina
©João Pedro Silva
This peacock worm lives in the seashore and other shallow zones. Its tubes are formed by a mucus secretion, in which particles of fine sediment are clumped together. Is normally buried in the mud or sand, keeping only the tentacles out.
Leptogorgia sarmentosa
©Emanuel Gonçalves
Like the other sea fans, this species is also a colony formed by many polyps, connected by a layer of coloured tissue.
Arnoglossus thori
©João Pedro Silva
The Thor’s scladfish lives on muddy sand bottoms, up to 300 meters deep. It feeds on a wide variety of animals, from small fish, worms, molluscs and crustaceans. The scaldfish can reach 20 cm in length and live up to 10 years.
Labrus mixtus
©Rúben Fortuna
The cuckoo wrasse resides in rocky reefs covered with algae, where it feeds mainly on crustaceans. Males build nests with algae, defending them from rivals while attracting females with elaborate mating rituals.
Alentia gelatinosa
©João Pedro Silva
This gelatinous scale worm can be found under stones on sandy bottoms, among algae or even in the burrows of other worms. The body is flattened and when disturbed it moves rapidly, reaching speeds of 2 cm per second.
Balistes capriscus
©Emanuel Gonçalves
The gray triggerfish can be found near rocky reefs where it feeds on small crustaceans and molluscs. During the breeding season, the males create holes in the sand that will serve as nests for the females to lay their eggs.
Doto koenneckeri
©João Pedro Silva
This small sea slug or nudibranch, does not exceed 10 mm in length. It lives exclusively on a specific hydrozoan (tiny colonial animals), from which it also feeds.
Peltodoris atromaculata
©João Pedro Silva
This sea slug, also known as Swiss cow nudibranch due to its dotted pattern and white body, feeds exclusively on sponges in shady areas of rocky bottoms. It can reach 120 mm in size.
Ctenolabrus rupestris
©João Pedro Silva
The goldsinny wrasse can live up to 8 years. It is found in shallow rocky areas like tide pools and in eelgrass prairies, where it feeds on crustaceans and sea snails. It is employed as a cleaning fish in salmon farms.
Catostylus tagi
©Luís Quinta
Being one of the most common jellyfish on Portuguese waters, it is easily observed on the coast of Arrábida. It is a large size species that although not especially dangerous, its sting can cause some pain, redness and a slight burning.
Felimida purpurea
©João Pedro Silva
This nudibranch - an animal belonging to the sea slugs’ group - can reach 50 mm in length. It is usually found in dimly lit places, on rocky bottoms, where it feeds on sponges.
Cystoseira usneoides
©Emanuel Gonçalves
The bushy bladder-chain wrack can be used as a bioindicator, since its presence relies on good water quality. This brown seaweed is rich in antioxidant and anti-inflammatory substances, some of them being studied for some possible antitumoral properties.
Thysanozoon brocchii
©Rui Guerra
When over rocky bottoms, covered with organisms, sometime this flatworm may be confused with some sea slugs. This animal can move in the water undulating its body.
Cliona celata
©Emanuel Gonçalves
The yellow boring sponge is named after its ability to dissolve limestone rocks and shells of molluscs by secreting acid. It is found in a wide variety of habitats, from coastal areas and estuaries to depths of 100 m.
Dendrodoris herytra
©João Pedro Silva
The sea slugs, a group to which this nudibranch belongs, usually have a pair of rhinophores (sensory organs associated with smell) in the frontal area of the body. This species is usually found under rocks and feeds on sponges.
Anemonia viridis
©Emanuel Gonçalves
The microscopic algae found in the tentacles of the snakelocks anemone are responsible for the green colour. This symbiotic relationship provides some nourishment to the anemone, although this is a voracious predator of small fish, crustaceans and molluscs.
Caryophyllia inornata
©João Pedro Silva
This small solitary cup-coral has a calcified exoskeleton (outer skeleton) and favors dimly lit or dark places, such as caves, crevices or rocky overhangs. It can be found in large numbers.
