Ampelisca eschrichtii Krøyer, 1842 ( Ampeliscidae) of the Sakhalin Shelf in the Okhotsk Sea starve in summer and feast in winter

• Main Authors: Durkina, Valentina B., Chapman, John W., Demchenko, Natalia L.
• Format: Other/Unknown Material
• Language: unknown
• Published: PeerJ 2018
• Subjects: Okhotsk; okhotsk sea; Sakhalin
• Online Access: http://dx.doi.org/10.7287/peerj.preprints.3496v2; https://peerj.com/preprints/3496v2.pdf; https://peerj.com/preprints/3496v2.xml; https://peerj.com/preprints/3496v2.html

Ampelisca eschrichtii Krøyer, 1842 of the Sakhalin Shelf of the Okhotsk Sea, Far Eastern Russia, comprise the highest known biomass concentration of any amphipod population in the world and are a critically important prey source for western gray whales. The high prevalence of atrophied ovaries, undersized and damaged oocytes, undersized broods of embryos and the absence of terminal phase males or females brooding fully formed juveniles among these populations in late spring and early fall are consistent with trophic stress and starvation. A. eschrichtii therefore appear to starve in summer and grow and reproduce in late fall and winter. In summer, these populations, occur below water strata containing the bulk of phytoplankton biomass and appear more likely to receive their trophic sources with vertical mixing that occurs in winter.