Sitka Shrimp

Heptacarpus sitchensis

Sitka Shrimp

Heptacarpus sitchensis
Other Common Names
Sitka coastal shrimp, Red-banded transparent shrimp, common coastal shrimp
Other Common Names
Sitka coastal shrimp, Red-banded transparent shrimp, common coastal shrimp

At the Aquarium

Sandy Coast

Appearance

Sitka shrimp come in variable colors, which is often due to the tissues beneath its translucent shell with reddish-brownish stripes. The legs also have red/brown bars. The black eyes project out from the carapace. The well-developed rostrum has 4-8 rigid teeth on the back side and up to 5 on the underside.

Habitat

Mid-intertidal to 40 feet deep on rocky coasts, or in eelgrass beds on mudflats or floats.

Diet

Likely omnivorous, will feed on the egg masses of an intertidal sea spider (Achelia simplissima).

Life History

Females can be found brooding eggs from May through September, with a female producing multiple broods in a year. Mating occurs shortly after a female molts. The male will place a spermatophore beneath the female’s first abdominal segment. When the larvae hatch, they are planktonic. After the larvae have hatched, the female will molt and then mate again. Females can reach lengths of 1.1 inches, with males being smaller, only reaching to 0.6 inches long. These shrimps do not live past 18 months.

IUCN Status

Not Evaluated

Ecosystem & Cultural Importance

Predators include fish
Alaska to Baja California, Mexico
This is a common intertidal shrimp that you may find while exploring tidepools.
Shrimp in this group exhibit body, gill, and embryo grooming to combat microbial fouling and parasites.
When feeding on the egg masses of an intertidal sea spider (Achelia simplissima), they must pick up a male sea spider carrying one or more egg masses to eat the eggs, but when finished feeding will drop the spider, leaving it unharmed..

Citations & Other Resources

  • Marilynne Box, Heptacarpus sitchensis, CC BY 4.0
  • Burris, Zair P. inchesCosts of exclusive male parental care in the sea spider Achelia simplissima (Arthropoda: Pycnogonida).inches Marine biology 158 (2011): 381-390.
  • Hiebert, T.C. 2015. Heptacarpus sitchensis. In: Oregon Estuarine Invertebrates: Rudys’ Illustrated Guide to Common Species, 3rd ed. T.C. Hiebert, B.A. Butler and A.L. Shanks (eds.). University of Oregon Libraries and Oregon Institute of Marine Biology, Charleston, OR.
  • Invertebrates of the Salish Sea website