crustaceans

The following species have been observed thus far in surveys of Fishing Bay and Indian Island. 
 Look for future updates.

crabs


  Flattop Porcelain Crab

(Petrolisthes eriomerus)


     Look for:  Round carapace
                          Reddish brown to vibrant blue
                          Exceptionally large, flat nippers
                          Very long thin antennae
                          Small: No more than 2 inches
     Diet:  Suspension feeder
    (play video at right to see the porcelain crab feeding)
    Abundance:  Seasonal, April – June
    
Notes:  The porcelain crab gets its name from its tendency to drop claws,  just like a fragile teacup.  The discarded limb is 
meant to  distract a would-be predator.  The crab will soon
molt and  re-grow the lost appendage.








Purple Shore Crab 
(Hemigrapsus nudus)

     Look for:  Oblong or rectangular purple carapace
                          Eyes wide apart
                          Nippers tucked under "chin"
                          Not aggressive
                          Small: No more than 2 inches
     Diet:  Grazer (algae, diatoms), scavenger
    Abundance:  Common






Green Shore Crab 
(Hemigrapsus oregonensis)

     Look for:  Oblong or rectangular greenish yellow carapace
                           Eyes wide apart
                           Nippers tucked under "chin"
                           Not aggressive
                           Small: No more than 2 inches
     Diet:  Grazer (algae, diatoms), scavenger
    Abundance:  Common
    
Similar Species:  The green shore crab can be distinguished 
from the purple shore crab by the presence of hairs on 
its knees.  Hemigrapsis nudus or "nude" refers to the lack
of hairs.



Black-clawed Crab
 
(Lophopanopeus bellus)

     Look for:  Coloration can vary from orange, red to blue 
                               and may be mottled
                           Fan-shaped carapace
                           Eyes close together
                           Smooth carapace, without "teeth" 
                           Thin, muscular, black-tipped nippers
                           Carapace may be bumpy but is smooth
                           Very aggressive
                           Small: up to 2 inches   
     Diet: Clams, snails, barnacles
     Abundance:  Seasonal
     Similar Species:  The black-clawed crab can be 
                        distinguished from the shore crab by its fan-
                         shaped  carapace.  The shore crab's 
                         carapace is more rectangular and is "toothed".  
                         The shore crab's eyes are also farther apart.


Helmet Crab 
(Telmessus cheiragonus)

     Look for:  Nearly round carapace
                          Eyes close together in middle
                           Yellowish green
                           Exoskeleton, carapace and legs completely covered
                                 with hairy bristles
                            Long, slender legs
     Diet:  Small invertebrates, algae
     Abundance:  Seasonal, April – May



Northern Kelp Crab 
(Pugettia producta)

     Look for:  Smooth shield-shaped carapace, green above
                          Prominent rostrum
                           Underside yellow and red
                           Long, thin legs
                           Large: can be 6–12 inches
                           Often seen in kelp beds
      Diet:  small invertebrates
      Abundance:  Common









Graceful Decorator Crab 
(Oregonia gracilis)

     Look for:  Narrow, pointy carapace
                           Two long rostral horns
                           Very thin, long, spidery legs
                           "Decorated" with sponges and algae
                            Small: under 2 inches
                            Usually seen in eelgrass
      Diet: Small invertebrates, algae
      Abundance:  Scarce








Graceful Kelp Crab 
(Pugettia gracilis)

     Look for:  Narrow, pointy carapace
                          Highly variable in color, often brown, yellow
                              or red, but can be white, orange, pink or blue
                           Two long rostral horns
                           Very thin, long, spidery legs
                           May decorate in moderation
                           Small: up to 3 inches
                           Usually seen in eelgrass
     Diet: Small invertebrates, algae
     Abundance:  Scarce

Similar Species:  The graceful kelp crab can be distinguished
from the graceful decorator by the amount of decoration.  If 
there is ample decoration, it is probably the decorator crab.  
If there is no decoration, it is likely the kelp crab.  If there is 
moderate decoration, look at the  shape of the carapace. The
 graceful kelp crab has  a shield or lance-point carapace with 
relatively  short, stubby legs. The decorator crab also has a  longer rostrum, about half the length of the carapace, with
two spine-like processes  instead of a flattened one.


Dungeness Crab 
(Metacarcinus magister)

     Look for:  Fan-shaped pinkish carapace
                          Eyes close together, short antennae 
                          Ten "teeth"–  last at widest point
                         Juveniles can be white, black, mottled
                         Aggressive, threat posture
                         Large: carapace can be 9  inches           
     Diet: Clams, snails, barnacles
     Abundance:  Common




Graceful Crab 
(Metacarcinus gracilis)

     Look for:  Fan-shaped pinkish carapace
                          Eyes close together, short antennae
                          Ten "teeth" –  last below widest point
                         Juveniles can be white, red, mottled
                         Aggressive, threat posture 
                         Large: carapace can be 5  inches
     Diet: Clams, snails, barnacles
     Abundance:  Common



Red Rock Crab 
(Cancer productus)

     Look for:  Fan-shaped red carapace
                          Eyes close together, short antennae
                           Nine "teeth" on each side of carapace
                          Juveniles can be finely striped
                          Black-tipped claws
                          Aggressive, threat posture
                          Large: carapace can be 8  inches            
     Diet: Clams, snails, barnacles
     Abundance:  Common



Pacific Rock Crab  
(Cancer antennarius)

     Look for:  Fan-shaped pink/red carapace
                          Eyes close together, short antennae
                          Nine "teeth" on each side of carapace
                          Red spotting on underside
                          Black-tipped claws
                          Juveniles: dense hair on carapace
                          Aggressive, threat posture
                          Large: carapace can be 7  inches            
     Diet: Clams, snails, barnacles
     Abundance:  Scarce
 







Pygmy Rock Crab 

(Cancer oregonesis)

     Look for:  Oval red/brown carapace
                           Eyes close together, short antennae
                           Nine "teeth" on each side of carapace
                           Black-tipped claws
                           Very hairy legs
                           Aggressive, threat posture
                           Small: carapace under 2  inches
    Diet: Clams, snails, barnacles
    Abundance:  Scarce









barnacles

Acorn Barnacle 

(Balanus glandula)

     Look for:  Light gray to white
                          Volcano-shaped.
                          Found in the mid to upper tidal area
                          At high tide, barnacles will extend tentacles to feed
                        Small: up to 2 inches tall and wide
     Diet:  Filter feeder, feeds on plankton
     Abundance:  Very common
     Some individuals can live up to 15 years!



porcelain crab

porcelain crab suspension feeding



purple shore crab






Green Shore Crab
green shore crab








black-clawed crab




helmet crab



northern kelp crab


graceful decorator crab
graceful decorator crab adorned with multiple ascidian




graceful kelp crab









Dungeness crab




graceful crab



red rock crab



pacific rock crab by peter_r.
Pacific rock crab


pygmy rock crab

pygmy rock crab





Photo of acorn barnacle
acorn barnacle
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