Zooplankton Species Composition
Zooplankton samples collected in winter 2006 and early spring 2007 show a copepod community that is dominated by cold–water subarctic species, namely Pseudocalanus mimus and Calanus marshallae. The copepods, Neocalanus plumchrus/flemingerii and N. cristatus have been unusually abundant this spring, and this has continued through May 2007. This is a very good sign, and these copepods have been found from inner shelf waters to at least 125 miles from shore.
This species composition indicates either a greater–than–average influx of subarctic waters (from the Gulf of Alaska) or a "normal" influx of subarctic waters containing a greater–than–average abundance of these copepods. Either case is good for fishes that feed on Neocalanus—in particular juvenile rockfish and sablefish. Thus, 2007 should be an excellent recruitment year for sablefish (black cod). Moreover, copepod biodiversity declined during winter 2007, indicating that a cold–water community has moved into the area.
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