Stout Shrimp     Heptacarpus brevirostris



The Stout shrimp, or short-spined shrimp, is one of several species of shrimp with the common name of "broken back" shrimp, named for the sharp angle of the attachment of the tail to the body.  It can be told from other broken back species by it's larger size and very short spine or rostrum in the middle of the head between the eyes.  It grows to 2.4 inches while most other broken back shrimp are smaller.  The body color is highly variable ranging from white mottling or stripes to browns and greens.


Stout shrimp regularly occur in the intertidal zone or along the sides of floats where they are often the most commonly seen shrimp.   During the day they can be found under seaweed, hidden around rocks or snuggled among mussels only coming out at night to forage for food.  Poking around the waterline of a float that is covered with attached seaweed and hydroids will often flush them out.  However they are seldom found out in the open on the surface of piling as are another species of shrimp called dock shrimp.  The stout shrimp can be found in protected areas from the Aleutian Islands of Alaska to the central coast of California.


Like many shrimp, the stout shrimp is mainly carnivorous feeding on a variety of animals including sea squirts.  Shrimp, in turn, are eaten by a variety of fish but only if they can catch them.  Shrimp use the rapid flexing of their tail to scoot away from danger.  The most successful fish are those who routinely use a sucking behavior to catch fast moving prey such as shrimp.


Stout shrimp breed from winter to spring with the females holding the eggs under the abdomen where they are protected for a short period until they hatch.  The larvae then swim in the plankton, metamorphosing several times until they look like small adults and settle to the bottom.