Spot prawn, Pacific prawn • Pandalus platyceros
Identification
Measuring up to 25 cm long, the spot prawn is the largest shrimp species found in North American waters. It is easily identified by the two pairs of spots on its "tail" (abdomen — specifically, the first and fifth segments) and the white bars running lengthwise along its carapace. The rest of the body is red, though juveniles may be more brownish or greenish.
Habitat & Range
The spot prawn inhabits rocky and sandy subtidal locations to depths of 485 m. Junveiles, which tend to inhabit shallower areas of the subtidal and are often found under sieve kelp blades (Agarum fimbriatum and A. clathratum), may also be found in the low intertidal. Its range extends from northern Alaska to southern California.
Human Uses
This is the most important commercially and recreationally trapped shrimp on the west coast of North America. Commercial trap and pot harvesting does not seem to have significant impacts on population, but an increase in demand has led to some larger-scale trawl net harvests which could have a greater impact on numbers and is more damaging to the shrimp's habitat. The Monterey Bay Aquarium Seafood Watch program lists spot prawns caught in British Columbia and Alaska as "Best Choice" while Washington and California harvests are labelled "Good Alternative."
Intriguing Info
A Vancouver Aquarium monitoring program in Howe Sound has observed that populations of new juvenile spot prawns at a given site tend to vary year-to-year based on the state of sieve kelp, which provides shelter for juveniles. Sieve kelp, which are perennial, can be destroyed by winter storms, overgrazing by sea urchins, and even damaged by sunflower stars (Pycnopodia helianthoides) which eat things that grow on the kelp blades.
The spot prawn is not the biggest west coast shrimp because it grows the fastest, but rather because it lives the longest. This species is male for the first part of its life, then changes to female.
iNaturalist
https://www.inaturalist.org/taxa/180394-Pandalus-platyceros
Measuring up to 25 cm long, the spot prawn is the largest shrimp species found in North American waters. It is easily identified by the two pairs of spots on its "tail" (abdomen — specifically, the first and fifth segments) and the white bars running lengthwise along its carapace. The rest of the body is red, though juveniles may be more brownish or greenish.
Habitat & Range
The spot prawn inhabits rocky and sandy subtidal locations to depths of 485 m. Junveiles, which tend to inhabit shallower areas of the subtidal and are often found under sieve kelp blades (Agarum fimbriatum and A. clathratum), may also be found in the low intertidal. Its range extends from northern Alaska to southern California.
Human Uses
This is the most important commercially and recreationally trapped shrimp on the west coast of North America. Commercial trap and pot harvesting does not seem to have significant impacts on population, but an increase in demand has led to some larger-scale trawl net harvests which could have a greater impact on numbers and is more damaging to the shrimp's habitat. The Monterey Bay Aquarium Seafood Watch program lists spot prawns caught in British Columbia and Alaska as "Best Choice" while Washington and California harvests are labelled "Good Alternative."
Intriguing Info
A Vancouver Aquarium monitoring program in Howe Sound has observed that populations of new juvenile spot prawns at a given site tend to vary year-to-year based on the state of sieve kelp, which provides shelter for juveniles. Sieve kelp, which are perennial, can be destroyed by winter storms, overgrazing by sea urchins, and even damaged by sunflower stars (Pycnopodia helianthoides) which eat things that grow on the kelp blades.
The spot prawn is not the biggest west coast shrimp because it grows the fastest, but rather because it lives the longest. This species is male for the first part of its life, then changes to female.
iNaturalist
https://www.inaturalist.org/taxa/180394-Pandalus-platyceros
References
Harbo, R. M. (1999). Whelks to whales: Coastal marine life of the Pacific Northwest. Madeira Park, BC: Harbour Publishing. P. 81.
Lamb, A., and Hanby, B. (2005). Marine Life of the Pacific Northwest [electronic version]. Madeira Park, BC: Harbour Publishing.
Spot Prawn. Monterey Bay Aquarium. Monterey Bay Aquarium Foundation. Accessed 22/02/2016.
The Life Cycle of the Spot Prawn in Howe Sound. Vancouver Aquarium. Accessed 22/02/2016.
Authors and editors of page
Kelly Fretwell (2016).
Harbo, R. M. (1999). Whelks to whales: Coastal marine life of the Pacific Northwest. Madeira Park, BC: Harbour Publishing. P. 81.
Lamb, A., and Hanby, B. (2005). Marine Life of the Pacific Northwest [electronic version]. Madeira Park, BC: Harbour Publishing.
Spot Prawn. Monterey Bay Aquarium. Monterey Bay Aquarium Foundation. Accessed 22/02/2016.
The Life Cycle of the Spot Prawn in Howe Sound. Vancouver Aquarium. Accessed 22/02/2016.
Authors and editors of page
Kelly Fretwell (2016).