Length-weight Relationships of Dolphinfish, Coryphaena hippurus, and Wahoo, Acanthocybium solandri: Seasonal Effects of Spawning and Possible Migration in the Central North Pacific

Weight-on-length (W-L) relationships for 2,482 dolphinfish, Coryphaena hippurus, and 1,161 wahoo, Acanthocybium solandri, were examined. Data on fork length, whole (round) weight, and sex were collected for dolphinfish at the Honolulu fish auction from March 1988 through November 1989. Unsexed weight and length data for wahoo were collected at the auction from July 1988 through November 1989. We also used sex specific weight and length data of 171 wahoo collected during 1977–1985 research cruises for analysis. Coefficients of W-L regressions were significantly different between the sexes for dolphinfish. Coefficients did not significantly differ between the sexes for wahoo based on research cruise data. In a general linear model evaluating month as a categorical factor, month was significant for female dolphinfish, male dolphinfish, and wahoo with sexes pooled. W-L and length-on-weight (L-W) relationships were fitted by nonlinear regression for all dolphinfish, female dolphinfish, male dolphinfish, and all wahoo sexes pooled. W-L relationships for monthly samples of female dolphinfish, male dolphinfish, and all wahoo with sexes pooled were also fitted by nonlinear regression. Predicted mean weight at length for wahoo was highest at the beginning of the spawning season in June and lowest after the spawning season in September. Maximum and minimum predicted mean weight at length for both sexes of dolphinfish did not correspond with the peak spawning period (March–May). Plausible migration models in conjunction with reproductive behavior were examined to explain the variability in monthly predicted mean weight at length for dolphinfish.

Regional Fisheries Advisory Committee 29th April, 1974

This is the first report from the Regional Fisheries Advisory Committee meeting, which was held on the 29th April, 1974. The report looks at sections on estimates for the anticipated income and expenditure on fisheries for the current year, the structure of fisheries in the region, and a list of the fisheries in the ownership of the North West Water Authority. Also covered is information relating to fishery and sea fishery byelaws, license duties and a summary of the current activity and the future plans for the committee. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.

Regional Fisheries Advisory Committee 21st July, 1975

This is the report from the Regional Fisheries Advisory Committee meeting, which was held on the 21st July 1975. The report contains information on the appointment of the Regional Fisheries Advisory Committee (1975-1976), the appointment of the Local Fisheries Advisory Committee (1975-1976), and the land drainage representation on Local Fisheries Committees. Also included in the report is information on fishery byelaws, fishing at Jumble Reservoir and a progress report on a proposed Coarse Fish Unit and coarse fish stock pools. Licence duties, long term angling leases on Authority Waters and radio equipment for Bailiffting Staff are also covered. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.

Regional Fisheries Advisory Committee 30th September, 1974

This is the report from the Regional Fisheries Advisory Committee meeting, which was held on the 30th September, 1974. The report covers the minutes from the previous meetings of the Local Fisheries Advisory Committees, the income from licence duties, and an interim report on the establishment of a coarse fish unit. Also included is the regional fish hatchery requirements and information on the ban of imports of wild freshwater fish due to fish disease. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.

Regional Fisheries Advisory Committee 3rd November 1975.

This is the report from the Regional Fisheries Advisory Committee meeting, which was held on the 3rd November 1975. The report contains information on the proceedings of the Local Fisheries Advisory Committee and recommendations for these committees, proposed Coarse Fish Unit, netting on the Solway Firth, fishing licence duties, fisheries improvement works on the River Leven and fishing at Jumbles Reservoir. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.

Regional Fisheries Advisory Committee 6th January, 1975

This is the report from the Regional Fisheries Advisory Committee meeting, which was held on the 6th January, 1975. The report covers the minutes from the previous meetings of the Local Fisheries Advisory Committees, information on the proceedings of the Fishery Licensing Sub-Committe and fisheries improvement work on the River Leven. Also included is information on the ban of imports of wild freshwater fish due to fish disease. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.

Regional Fisheries Advisory Committee 9th February, 1976.

This is the report from the Regional Fisheries Advisory Committee meeting, which was held on the 9th February 1976. The report contains information on the proceedings of the Local Fisheries Advisory Committee and recommendations for these committees and Worthington Coarse Fish Unit. It also covers fishing licence duties, fisheries improvement work on the River Leven, proposed new code of fisheries byelaws, the seminar on water conditions harmful to fish life and Heysham and Lancaster sewage disposal. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.

Regional Fisheries Advisory Committee 3rd May, 1976.

This is the report from the Regional Fisheries Advisory Committee meeting, which was held on the 3rd May 1976. The report contains information on the regional fisheries organization, the review of the Water Industry in England and Wales, fisheries improvement work on the River Leven, Mitton Hatchery, new code of fishery byelaws, proposed byelaws (Coniston) and temporary licences. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.

Regional Fisheries Advisory Committee 24th February, 1975

This is the report from the Regional Fisheries Advisory Committee meeting, which was held on the 24th February, 1975. The report covers the minutes from the previous meetings of the Local Fisheries Advisory Committees, Licence duties and regional fish hatchery requirements. Also included is the consolidation of the Salmon and Freshwater Fisheries Acts, fishery byelaws and a brief note on fisheries improvement work on the River Leven. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.

Regional Fisheries Advisory Committee 25th April, 1977.

This is the report from the Regional Fisheries Advisory Committee meeting, which was held on the 25th April 1977. The report contains the minutes of the previous meetings of the Local Fisheries Advisory Committees, fisheries income and expenditure and information on the distribution of licences. The report also includes the National Water Council Review of Discharge Consent Conditions Consultation Paper, and information on fishery byelaws and netting on the Solway Firth. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.

Regional Fisheries Advisory Committee 12th May, 1975

This is the report from the Regional Fisheries Advisory Committee meeting, which was held on the 12th May, 1975. The report covers the minutes from the previous meetings of the Local Fisheries Advisory Committees, licence duties, fishery byelaws, and regional fish hatchery requirements. Also included is information on the long term angling leases on Authority waters. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.

Regional Fisheries Advisory Committee 18th July, 1977

This is the report from the Regional Fisheries Advisory Committee meeting, which was held on the 18th July 1977. The report contains the minutes of the last meetings of the Local Fisheries Advisory Committees, information on fisheries income and expenditure and fisheries byelaws. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.

Regional Fisheries Advisory Committee 14th November, 1977

This is the report from the Regional Fisheries Advisory Committee meeting, which was held on the 14th November 1977. The report includes the minutes of the previous meetings of the Local Fisheries Advisory Committees, information on income and expenditure and a summary of recommendations. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.

Regional Fisheries Advisory Committee 2nd December, 1977

This is the report from the Regional Fisheries Advisory Committee meeting, which was held on the 2nd December 1977, in which it covers the minutes of the previous Regional meeting. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.

Regional Fisheries Advisory Committee 6th February, 1978

This is the report from the Regional Fisheries Advisory Committee meeting, which was held on the 6th February 1978. The report contains the minutes of the previous meetings of the Local Fisheries Advisory Comittees, information on fisheries income and expenditure and terminated angling leases. Also included is the update on the fishery regulations on Worthing Reservoirs. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.