ARMORED SAND STAR (Astropecten armatus)
Habitat: Sandy bottoms to 60m from Southern
California to Ecuador.
Size: 15 cm (6 in)
Position in food web: Carnivorous: Feeds on
mainly on snails but also eats dead fish, sand
dollars and sea pansies. Prey for large fish,
large sea stars, and sea otters.
Interesting facts:
Unlike most sea stars, the tube feet of the
armored sand star lack suckers.
The sand star differs from many other sea
stars when feeding, as this star does not
evert its stomach, but rather swallows prey
whole.
Relatives: sea cucumbers, sand dollars, and sea urchins
BAT STAR (Asterina miniata)
Habitat: Low intertidal zone and rocky reefs to 300 m from Alaska to Baja California.
Size: 10 cm (4 in)
Position in food web:
Omnivorous/Scavenger: Feeds on plants
and animals, especially algae, tunicates
and surfgrass. Prey for shore birds,
predatory sea stars, certain species of fish,
and land-based animals such as raccoons
and weasels.
Interesting Facts:
The bat star extends its stomach out as
it walks ―sweeping‖ food particles into
its mouth
Sea stars have the ability to
regenerate, or grow back, arms if lost
Does not possess any pedicellariae,
one of the small pincer-like structures used for cleaning and to capture tiny prey.
Relatives: sea urchins, sand dollars, and sea cucumbers
BRITTLE STAR (various species)
Habitat: Various habitats to 140 m
from British Columbia to Southern
California.
Size: Disk diameter from 1 cm (.5 in)
to 4.5 cm (2 in) with some species
having arms 2-9 times as long as disk
diameter
Position in food web: Carnivorous:
Feeds on organic particles, detritus
and small animals. Prey for sea stars,
fishes and crabs.
Interesting facts:
The brittle star can move quite rapidly with serpentine like movements of the arms
Not much is known about the CA species of brittle stars with regards to feeding, life
span, predators, parasites, etc. Much of information we know is from related species
This species gets its name due to the flexible, thin arms that are easily broken off but
then can be regenerated
Relatives: sand dollars, sea urchins, sea cucumbers, and sea stars
KNOBBY SEA STAR (Pisaster giganteus)
Habitat: Very low intertidal and
rocky reefs to 88 m from British
Columbia to Baja California.
Size: 30 cm (12 in) arm radius
Position in food web:
Carnivorous: Feeds on mussels,
clams, snails, chitons and
barnacles. Prey for lobsters, gulls,
larger sea stars including the
sunflower star.
Interesting facts:
Knobby sea stars are active
predators often times seen
feeding on the same piece of
food with the Kellet’s Whelk
The aboral side (top) of the knobby sea star, like many other species of sea stars, is
covered in tiny pincher-like structures called pedicellariae, which can move food
particles from the aboral side to oral (bottom) side to their mouth.
Relatives: sea stars, sand dollars, and sea cucumbers
LEATHER STAR (Dermasterias imbricata)
Habitat: Rocky reefs to 90m from Alaska to
San Diego.
Size: 12 cm (4.7 in)
Position in food web: Carnivorous: Feeds
mostly on anemones, but also eats sea urchins
and sea cucumbers.
Interesting facts:
Unlike many other types of sea stars,
the leather star typically swallows its
prey whole and digests it internally
Leather stars often have a sulfur or
garlic odor
When leather stars come in contact
with anemones, some anemones detach and swim away to avoid predation.
Relatives: sand dollars, sea urchins, and sea cucumbers
OCHRE STAR (Pisaster ochraceus)
Habitat: Intertidal and rocky reefs
to depths of 88 m from Alaska to
Baja California.
Size: 14 cm (5.5 in) arm radius
Position in food web:
Carnivorous: Feeds on mussels,
barnacles, snails, chitons and
limpets. Adults have few predators
but some times eaten by otters and
gulls.
Interesting facts:
Many prey items of ochre
star’s have evolved to have
responses that help them
escape or avoid predation. They either move away when they detect an ochre star
scent in the water or when they are touched by the sea star.
This species of sea star is more tolerant to air exposure than other species of Pisaster,
often being exposed for 8 hours during tidal changes
Relatives: sand dollars, sea urchins, and sea cucumbers
SHORT-SPINED STAR (Pisaster brevispinus)
Habitat: Subtidal zone and rocky reefs to
depths of 100 m from Alaska to San Diego
Size: 32cm (13 in) arm radius
Position in food web: Scavenger/Carnivorous:
Feeds on snails, clams, sand dollars, dead fish
and squid. Prey for shore birds, sea otters, and
larger predatory sea stars.
Interesting facts:
The short-spined sea star is able to sense a
buried clam under the sediment while
walking over it. They are able to extend
their tube feet into the sand (sometimes 20
cm down) to grab the clam, can dig down
to the clam (which can take 2-3 days) or can extend stomach out to depths of 8 cm to
digest the prey in place
Unlike its sea star relatives, the short-spined sea star dries out (desiccates) quickly
when removed from the water
Relatives: sand dollars, sea urchins, and sea cucumbers
PURPLE SEA URCHIN (Strongylocentrotus purpuratus)
Habitat: Low intertidal zone, rocky reefs and
kelp forests to 160 m from British Colombia
to Baja California.
Size: test 5 cm (2 in) in diameter
Position in food web: Herbivorous: Feeds on
brown and red algae. Prey for sea stars, fish
(sheephead), sea otters, and spiny lobsters.
Interesting facts:
Purple sea urchins feed on the holdfasts
of kelp causing the main frond of the kelp
to become detached, float away, and die.
To control this occurrence, predators keep
the urchin populations in check. When
predator population decline, entire areas of kelp forest may quickly be destroyed
leaving behind an ―urchin barren‖
Sea urchins have five white teeth on the bottom known as the ―Aristotle’s lantern‖ for
its lantern-like shape. In the lab they can grow out a new set of teeth in about 75 days
The sea urchin use their spines and their teeth to create depressions and burrows in
rocks where they live
Relatives: sea stars, sand dollars, and sea cucumbers
SAND DOLLAR (Dendraster excentricus)
Habitat: Shallow sandy bottoms to 40 m
from Alaska to Baja California
Size: 7.5 cm (3 in)
Position in food web: Omnivorous: Feeds
on small crustaceans, organic debris, and
algae fragments. Prey for shore birds, sea
stars, sheephead, and flatfish.
Interesting facts:
Juveniles tend to ingest sand while
feeding, which they store in their gut.
Some scientists believe this acts as a
―weight belt‖ aiding the animal by
keeping it stable in a shifting
environment
Sand dollars are compressed sea urchins with smaller bristle-like spines.
Life span is approximately 6-10, but sometimes can live for 13 years. Growth
rings on the test can be counted to age these animals.
Relatives: sea stars, sea urchins, and sea cucumbers
SAND DOLLAR (Dendraster excentricus)
Habitat: Shallow sandy bottoms to 40 m
from Alaska to Baja California
Size: 7.5 cm (3 in)
Position in food web: Omnivorous: Feeds
on small crustaceans, organic debris, and
algae fragments. Prey for shore birds, sea
stars, sheephead, and flatfish.
Interesting facts:
Juveniles tend to ingest sand while
feeding, which they store in their gut.
Some scientists believe this acts as a
―weight belt‖ aiding the animal by
keeping it stable in a shifting
environment
Sand dollars are compressed sea urchins with smaller bristle-like spines.
Life span is approximately 6-10, but sometimes can live for 13 years. Growth
rings on the test can be counted to age these animals.
Relatives: sea stars, sea urchins, and sea cucumbers
WARTY SEA CUCUMBER (Parastichopus parvimensis)
Habitat: Rocky reefs and sandy bottoms to 30 m
from Monterey California to Baja California.
Size: 25 cm (10 in)
Position in food web: Scavenger: Feeds on small
organisms and organic detritus in sediment. Prey
for sea stars, sea otters, and humans.
Interesting facts:
Sea cucumbers use camouflage as their first
line of defense against predators. Like many
other species of sea cucumbers, the warty sea
cucumber will eject its internal organs
(eviscerate) when threatened by predators in
hopes that the organs will be eaten in place of
the individual. The organs can be regenerated
later.
Although the warty sea cucumber looks intimidating at first, the papillae, or pseudo
spines, on the dorsal (top) side are soft and gel-like.
This species of cucumber moves more rapidly than others, about 1 m in 15 minutes
Relatives: sea stars, sand dollars, and sea urchins