Diablo Canyon power plant site ecological study Annual Report July 1, 1976 - June 30, 1977 and Quarterly Report no. 16 April 1, 1977 - June 30, 1977

More stations were surveyed during this report periodthan during any previous period. A total of 818 mandayswas spent surveying 18 permanent and 67 randomsubtidal stations, 19 permanent and 50 random intertidalstations, and 64 sportfish catch-per-unit-of-effortstations, as well as conducting corollary laboratorywork.In the subtidal areas, Laminaria dentigera and Pterygophoracalifornica, both important subsurface kelpspecies, increased in their combined total numbers fromthe 1976 survey. However, Nereocystis luetkeana, thebull kelp, declined substantially in all study areas.Population trends of many of the dominant subtidalmacro-invertebrates have varied depending on the speciesand on the type of method utilized. Regression analyseshave been performed on selected species for numbersversus depth. Red algal abundance and diversity appearto have increased in both subtidal study areas.Of the three observation areas, sea otters were observedleast frequently in Diablo Cove. However, there continuesto be fresh evidence of otter foraging withinDiablo Cove.Several seasons' data for intertidal algae and invertebrates have been summarized for one study area. While the algae biomass shows a fairly clear seasonality ofabundance, the trends in numbers of the six invertebratespecies considered are not as well defined.Because of high variability in the data, the sportfishcatch-per-unit-of-effort and hook-and-line study wascancelled in December.Populations of intertidal red and black abalones,Haliotis rufescens and H. cracherodii, respectively,appear to have remained fairly stable during the1976-77 period.Two other ancillary studies were also terminated duringthis period: interviews of commercial abalone andurchin fishermen, and observations of foam in Diablo Cove. (107pp.)

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Bibliographic Details
Main Authors: Gotshall, Daniel W., Laurent, Laurence L., Grant, John J.
Format: monograph biblioteca
Language:English
Published: California Department of Fish and Game, Marine Resources Region 1978
Subjects:Ecology, Fisheries, Biology,
Online Access:http://hdl.handle.net/1834/18030
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