Ecology of herring and other forage fish as recorded by resource users of Prince William Sound and the outer Kenai Peninsula, Alaska

Brown, E; Seitz, J; Norcross, B; Huntington, H

We documented qualitative ecological information about non-harvested fish age classes and species from resource users and area residents. Our primary objective was to compile local and traditional ecological knowledge about the distribution, abundance, ecology, and associated changes over time of Pacific herring Clupea pallasi and other forage fish species in Prince William Sound (PWS) and the Outer Kenai Peninsula (OK) in Southcentral Alaska. A secondary objective was to provide ecological information to aid in developing study or management plans concerning herring and other forage fish. Both objectives were met by developing an oral interview protocol, selecting and interviewing key informants in 5 Alaskan communities, and developing a geographic database. Researchers tape-recorded and mapped respondents' observations. Survey questions fell into 6 categories: 1) life history stage and species of the fish observed, 2) fish behavior and school characteristics, 3) presence and behavior of co-occurring predators, 4) seasonal spatial distributions observed, 5) decadal shifts observed, and 6) observation and method activity. The earliest observation was from 1934. Observations came from planes, net catches, visual sightings, and sonar output. Most observations were made during summer (June through August), probably due to both shallow distribution of schools and an increase in human activity during this season. In PWS the spring spatial distribution of herring was significantly different from summer and fall-winter, but the latter 2 were not significantly different. Spatial distributions of herring in the OK were significantly different from one another in all 3 seasons, and the differences were more highly significant than in PWS. Most observations concerned juvenile herring, but locations of herring spawning overlap with adult herring, Pacific sand lance Ammodytes hexapterus, capelin Mallotus villosus, capelin spawning, and eulachon Thaleichthys pacificus were also documented. Most respondents were able to distinguish herring from other species by their school shape, school color, behavior, and location within a bay. Some pilots believed sunny days were better than overcast days for distinguishing herring from forage fish schools because herring schools 'flash silver' and forage fish (mainly sand lance), also called 'feed fish' or 'bait fish,' look brown or gold. Pilots said that they did not see schools of salmon fry from the air. Juvenile herring were reported as broadly distributed, mainly in bays in PWS and the OK, and easily observed in the summer. Juvenile herring were found at the heads of bays during the winter. They were seen in winter with adult herring in a very limited number of sites. Decadal shifts were observed with an increase in juvenile herring from the 1970s to the 1980s and a much more restricted distribution in the 1990s. In PWS the 1970s distribution was not significantly different from the 1980s, but was highly significantly different from the 1990s. The 1980s and 1990s were also highly significantly different from one another. In the OK all 3 decades were significantly different from one another, and the level of significance was higher than for the PWS pairwise tests. Decadal shifts in the reported extent of juvenile herring distribution matched decadal trends in catches of the PWS adult herring population indicating that traditional ecological knowledge is a potentially valuable source of information for indicators of recruitment and population trends. Juvenile herring overlapped sandlance distribution to a large degree, and capelin and eulachon to a small degree. %Z online resource **This information is imported from the Legacy field in NatureBib** DATABASE MANAGEMENT NOTE: This record was loaded from the database (C:\Betty\NPS March04 Deliverables\ABR_NRBIB_Set2\ABR_NRBib_data_Set2_load.mdb) into the Oracle database on 5/24/2004 **This information is imported from the Legacy field in NatureBib**

Ecology of herring and other forage fish as recorded by resource users of Prince William Sound and the outer Kenai Peninsula, Alaska

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