"Research in Alaska"

An essential component of any mark and recapture study that seeks to estimate fish population abundance, exploitation rates, or migration rates from tagging data is the tag-reporting rate. We obtained tag-reporting rates for the sablefish Anoplopoma fimbria fishery during 1980–1998 by comparing tag returns in the fishery to tag returns from a scientific survey where all tag recoveries were assumed to be reported. Analytical formulae were derived for the measurement error associated with the estimates. When pooled over geographic areas or years, estimates of reporting rates were reasonably precise with coefficients of variation (CVs) usually less than 25%. Reporting rates were highest in the central (0.385) and eastern (0.315) Gulf of Alaska, intermediate in the western Gulf of Alaska (0.269), and lowest in the Aleutians (0.174) and Bering Sea (0.169). Rates pooled over all areas increased from lows of 0.102–0.248 in 1980–1982 to a peak of 0.465 in 1985 before declining to 0.199 in 1986 and 0.157 in 1987. The reporting rate increased gradually and fluctuated between 0.376 and 0.450 since 1995. The increase in reporting in 1995 was coincidental with the implementation of the Individual Fishing Quota (IFQ) system. The linear increase in reporting rates during 1986–1998 was significant. Factors that may have influenced the reporting rate were the number of tags available for recovery, the length of the commercial fishing season, the presence of scientific observers on commercial vessels, and the tag reward program. Pooled over all years and areas the tag-reporting rate has been 0.276 with a CV of 4.2%.

Between 1911 and 1984, northern fur seal (Callorhinus ursinus) research was carried out by Canada, Japan, Russia, and the United States under the Treaty for the Preservation and Protection of Fur Seals and Sea Otters. Since 1984, studies have been carried out independently by cooperating former member nations.

Between 1911 and 1984, northern fur seal research was carried out by Canda, Japan, Russia, and the United States under the Treaty for the Preservation and Protection of Fur Seals and Sea Otters. Since 1984, studies have been carried out independently by cooperating form member nations.

Between 1911 and 1984, northern fur seal research was carried out by Canada, Japan, Russia and the United States under the Treaty for the Preservation and Protection of Fur Seals and Sea Otters. Since 1984, studies have been carried out independently by cooperating former member nations.

Between 1911 and 1984, northern fur seal research was carried out by Canada, Japan, Russia, and the United States under the treaty for the Preservation and Protection of Fur Seals and Sea Otters. Since 1984, studies have been carried out independently by cooperating former member nations.

Between 1911 and 1984, northern fur seal research was carried out of Canada, Japan, Russia, and the United States under the Treaty for the Preservation and Protection of Fur Seals and Sea Otters. Since 1984, studies have been carried out independently by cooperating former member nations.

The population status of northern fur seals Callorhinus ursinus ) on st. Paul Island has been monitored annually since 1911. Annual reports of research on the population status of northern fur seals on all U. s. breeding rookeries (including st. Paul Island) and throughout their pelagic North Pacific and Bering Sea range (Fig. 1) have been published since 1940 excluding, a 3-year break during World War II. This series of publications, first produced by the Marine Mammal Biological Laboratory (later to become the National Marine Mammal Laboratory) represents one of the longest-running documentations of life history patterns and dynamics of a wild animal population. From 1911 to 1984, northern fur seal research was carried out by Canada, Japan, the Soviet Union, and the United States under a convention for the conservation of North Pacific fur seals. Since 1984, studies have been conducted independently, but cooperatively by former member nations.

Scientists from the National Marine Mammal Laboratory have published reports of annual studies of northern fur seals from the Pribilof Islands since 1958, and from San Miguel Island off Southern California since 1968. This document presents the results of research conducted in 1992.

This report summarizes northern fur seal (Callorhinus ursinus) research conducted by scientists from the National Marine Mammal Laboratory in 1991. Research was conducted on St. George Island and St. Paul Island of the Pribilof Island group in the eastern Bering Sea, and on San Miguel Island and Castle Rockin Southern California.

This report summarizes the research carried out by scientists from the National Marine Mammal Laboratory at four northern fur seal breeding sites during 1990.