Rep16 - Bering Sea - Key Species

## Key Species

Target species were chosen to represent key elements of the holoplanktonic assemblages on the Bering Sea shelf and their pelagic predators. The program focuses on copepods and euphausiids, their pelagic prey and predators. Since the main question focuses on how climate affects the carrying capacity, the program targets the dominant species within the ecosystem. Additional criteria used to select key species included the following:

- Likely to be impacted under hypothetical climate change scenarios.
- Economically or ecologically important
- Evidence that life history variability is linked to environmental variability.
- Widely distributed, providing opportunity for regional comparisons.
- Life-histories and/or ecological interactions representative of many other species.
- Demonstrated evidence of long-term shifts in abundance.
- Distribution associated with physical features and/or faunal boundaries.
- Analogous species occur in other ecosystems.

Based on these criteria, the following key species were identified for the Bering Sea program.

Zooplankton: Copepods: (Calanus marshallae, Neocalanus cristatus, N. plumchrus, Pseudocalanus spp., and Oithona spp.); Euphausiids (Thysanoessa longipes, T. inermis, T. raschii)

Seabirds: Least auklet (Aethia cristatella)

Pelagic Fish Stocks: walleye pollock, Pacific herring (Clupea harengus pallasi); sockeye salmon, pink salmon, chum salmon

Non-Commercial Forage Fish: capelin (Mallotus villosus), sand lance (Ammodytes hexapterus), myctophid and bathylagid fishes

Other Invertebrates: "Jellyfish" (scyphozans and hydrozoans), cephalopods, and chaetognaths

Several other important species/species groups were identified because they may play an important role in controlling the abundance or distribution of key predators on zooplankton or might be sensitive indicators of changes in abundance or distribution of key planktivores. These species include: Northern fur seals (Callorhinus ursinus), kittiwakes (Rissa), murres (Uria), piscivorous flatfish, Pacific cod (Gadus macrocephalus).