The geographic basis for population structure in Fraser River chinook salmon (Oncorhynchus tshawytscha)

We surveyed variation at 13 microsatellite loci in approximately 7400 chinook salmon sampled from 52 spawning sites in the Fraser River drainage during 1988–98 to examine the spatial and temporal basis of population structure in the watershed. Genetically discrete chinook salmon populations were associated with almost all spawning sites, although gene flow within some tributaries prevented or limited differentiation among spawning groups. The mean FST value over 52 samples and 13 loci surveyed was 0.039. Geographic structuring of populations was apparent: distinct groups were identified in the upper, middle, and lower Fraser River regions, and the north, south, and lower Thompson River regions. The geographically and temporally isolated Birkenhead River population of the lower Fraser region was sufficiently genetically distinctive to be treated as a separate region in a hierarchial analysis of gene diversity. Approximately 95% of genetic variation was contained within populations, and the remainder was accounted for by differentiation among regions (3.1%), among populations within regions (1.3%), and among years within populations (0.5%).Analysis of allelic diversity and private alleles did not support the suggestion that genetically distinctive populations of chinook salmon in the south Thompson were the result of postglacial hybridization of ocean-type and stream-type chinook in the Fraser River drainage. However, the relatively small amount of differentiation among Fraser River chinook salmon populations supports the suggestion that gene flow among genetically distinct groups of postglacial colonizing groups of chinook salmon has occurred, possibly prior to colonization of the Fraser River drainage.

Evaluation and application of microsatellites for population identification of Fraser River chinook salmon (Oncorhynchus tshawytscha)

Variation at 13 microsatellite loci was previously surveyed in approximately 7400 chinook salmon (Oncorhynchus tshawytscha) sampled from 50 localities in the Fraser River drainage in southern British Columbia. Evaluation of the utility of the microsatellite variation for population-specific stock identification applications indicated that the accuracy of the stock composition estimates generally improved with an increasing number of loci used in the estimation procedure, but an increase in accuracy was generally marginal after eight loci were used. With 10–14 populations in a simulated fishery sample, the mean error in population-specific estimated stock composition with a 50-popula-tion baseline was <1.4%. Identification of individuals to specific populations was highest for lower Fraser River and lower and North Thompson River populations; an average of 70% of the individual fish were correctly assigned to specific populations. The average error of the estimated percentage for the seven populations present in a coded-wire tag sample was 2% per population. Estimation of stock composition in the lower river commercial net fishery prior to June is of key local fishery management interest. Chinook salmon from the Chilcotin River and Nicola River drainages were important contributors to the early commercial fishery in the lower river because they comprised approximately 50% of the samples from the net fishery prior to mid April.

Nutrient Enhanced Coastal Ocean Productivity (NECOP). Data report: CTD and hydrographic data, R/V Pelican cruise, April 3-11, 1993

The Nutrient Enhanced Coastal Ocean Productivity (NECOP) Program is a component of NOAA's Coastal Ocean Program. The central hypothesis of this research is: Anthropogenic nutrient inputs have enhanced coastal ocean productivity with subsequent impacts on coastal ocean water quality, living resource yields, and the global marine carbon cycle. The initial study area for this program is the Mississippi/Atchafalaya River Outflow and adjacent Louisiana shelf region.

Community metabolism, P/R ratio and photosynthetic efficiency of a brackishwater farm

The productivity level of a brackishwater fish culture farm consisting of 25 ponds, with a water spread area of 2.5 ha, was studied. Gross community photosynthesis of the farm was found to be 46.32 Kcal/m2/day, which is equivalent to the release of 13.23 of O2/m2/day, or the fixing of 4.10 gC/m2/day. Respiratory demand of the farm was estimated to be 44.66 kcal/m2/day, which is equivalent to the uptake of 12.76 g O2/m2/day or the utilization of 3.95 gC/m2/day. Photosynthetic efficiency of the farm was high at 2.26%. The P/R ratio was 1.04, showing eutrophic nature.

A report on a survey with the r/v "Ernst Haeckel" in July-August 1980: shallow-water shrimp and by-catch, oceanography

A survey of the Sofala Bank (Mozambique) was conducted to: estimate the abundance of shallow-water shrimp in the area between 16 degree 20'S and 20 degree 20'S, from 5 to 100 meters; estimate the shallow-water shrimp species composition and distribution pattern of main species. Collect biological data of the main species, Penaeus indicus and Metapenaeus monoceros; study the shrimp by-catch, species composition and biological data collection of the most abundant species of commercial value; and collect environmental data to clarify the shelf circulation on the Sofala Bank and the main oceanic features in the regions 15 degree S to 18 degree S and south of 22 degree S.

Economics of operation of 38' G.R.P. fishing vessels issued by the A.D.B. Fisheries Project: a case study

The author gives a financial and economic valuation of the operation of vessels in the 38 foot GRP class. He discusses particularly the materials and methods of fishing they use, species composition of their catches, their rate of return, break-even analysis, financial and social analysis.

Abalone R&D at AQD

Details are given of the results of research conducted at the SEAFDEC Aquaculture Department on abalone (Haliotis asinina). The following areas are covered: reproductive biology; induced spawning; raising abalone in the hatchery; and, cage culture trials.