Fig. 2. Areas of major winter and spring concentrations of Pacific herring in Bristol Bay and the Bering Sea.
Fig. 3. Areas of major concentrations of king and snow crab in Bristol Bay and the Bering Sea.
Routes of Interaction Between Marine Birds and Commercial Fish
The obvious ways in which marine birds and fish of commercial importance interact in the eastern Bering Sea are illustrated by the simplified food web diagram in Fig. 4. The major animal groups and species included in two of the categories in this figure—secondary producers (invertebrate forage) and intermediate carnivores (commercial and forage marine fish and shellfish)—are as follows:
- Secondary producers
- Zooplankton and micronekton
- Copepods
- Calanus spp.
- Eucalanus spp.
- Euphausiids
- Thysanoessa spp.
- Amphipods
- Parathemisto spp.
- Gammarus spp.
- Pteropods
- Spiratella spp.
- Clione spp.
- Chaetognaths
- Sagitta spp.
- Benthos
- Polychaetes
- Nereis spp.
- Euroe spp.
- Molluscs
- Mytilus edulis
- Tonicella spp.
- Fusitriton oregonensis
- Echinodermata
- Strongylocentrotus spp.
- Crustacea
- Gammaridae
- Mysidae
- Idothea spp.
- Pagurus spp.
- Hapalogaster spp.
- Sclerocrangon spp.
- Intermediate carnivores
- Eggs (littoral, adhesive)
- Clupeidae
- Pelagic larvae
- Gadidae
- Pleuronectidae
- Osmeridae
- Ammodytidae
- Salmonidae
- Gadidae
- Pandalidae
- Juvenile and small adults
- Clupeidae
- Osmeridae
- Ammodytidae
- Salmonidae
- Gadidae
- Pandalidae
- Large adults
- Clupeidae
- Gadidae
- Pleuronectidae
- Salmonidae
- Scorpaenidae
- Lithodidae
- Majidae
- Pandalidae
- Marine birds
- Alcidae
- Procellariidae
- Laridae
- Phalacrocoracidae
Fig. 4. Food web in the eastern Bering Sea, showing routes of interaction between marine birds and the various life history stages of commercial fish and shellfish.