Pandalus danae Stimpson, 1857  Common name(s): Dock shrimp, coon-stripe shrimp
Synonyms:
Phylum Arthropoda  Subphylum Crustacea   Class Malacostraca     Subclass Eumalacostraca      Superorder Eucarida       Order Decapoda         Suborder Pleocyemata          Infraorder Caridea (true shrimp)           Family Pandalidae
	Pandalus danae, about 8 cm long, from 100 m depth in San Juan Channel
	(Photo by: Dave Cowles, July 2004)

How to Distinguish from Similar Species: Pandalus stenolepis has 3-5 pairs of small lateral spines on the telson and the outer margin of its antennal scale is concave.  Although it has reddish stripes on the sides of its abdomen, they angle upward posteriorly rather than downward.

Note:  According to the American Fisheries Society, this species should be called "dock shrimp" and the term "coonstripe shrimp" should be reserved for P. hypsinotus

Geographical Range: Alaska to Monterey, CA

Depth Range: Adults are just subtidal to 185 m.  Juveniles live shallower and may even be low intertidal.

Habitat: Rocky and sandy benthic or often found on docks.

Biology/Natural History: Live on rocky or sandy/shelly bottoms.  Juveniles hide in rock crevices or under algae during the day.  Eat polychaetes.  The left and right second pereopods are different from one another.  The carpus of the left pereopod is divided (multiarticulated) into about 60 articles, while the right has 18-21.  Predators include lingcod and pelagic cormorants.  The species are protandrous hermaphrodites (male first, then female).  After the female molts in November they mate.  The female carries her eggs on the abdomen until April, when they hatch into pelagic (swimming) larvae.  The species can live for up to 3 years.

References:

General References:
  Gotshall and Laurent, 1979
  Kozloff, 1993
  Lamb and Hanby, 2005
  O'Clair and O'Clair, 1998

Scientific Articles:
Komai, T., 1999.  A revision of the genus Pandalus (Crustacea: Decapoda: Caridea: Pandalidae).  Journal of Natural History 33: pp 1265-1372

This species is fished for sport and commercially.  It is one of the most commonly encountered large shrimp in our area found shallowly and on docks.

Top view of Pandalus danae head.  Photo by Dave Cowles, July 1997

 

These two views of the abdomen show that the third abdominal segment (at the top of the arch) is not laterally compressed, it does not have a strong mid-dorsal median ridge running down its length, and it does not have a dorsal spine.  The second abdominal segment has a transverse dorsal groove.  Note also the blue spots on segments two and six.  Photos by Dave Cowles, July 2008

The telson has six pairs of  spines running down the lateral edges of the dorsal side  (note the last pair is very close to the end), plus terminal spines.

The spine is longer than the lamella on the antennal scale.
 

Shrimp of this species are able to live on a remarkably small set of resources.  Rosario Beach Marine Lab obtains its clean seawater from intake valves in the bay.  Screens on these intakes filter out anything larger than about 1 mm.  The water is pumped up into a large holding tank, then feeds by gravity down to our labs.  The entire system is turned off and drained each mid-August at the end of the session, leaving only 10 cm or so of seawater and some silt at the bottom of the holding tank.  The system is then locked up and remains closed until the next mid-June.  In the summers of 2014 and 2015 we discovered individuals of this species living in the silt at the bottom of the holding tank when it was opened in June.  This pale individual, about 12 cm total length (eye socket to telson),  was the sole individual in the tank in June 2015.  He would have had to have entered the system as a larva the previous summer, and had lived in continuous darkness with little food except other larvae and silt, for 10 months until the tank was opened.  When first removed his eyes reflected light very brightly.  This photo was taken about 2 weeks after he was removed from the tank.  By this time his eyes no longer glow brightly.  Photo by Dave Cowles, July 2015.