The Northern Rockfish, Sebastes polyspinis, in Alaska: Commercial Fishery, Distribution, and Biology

The northern rockfish, Sebastes polyspinis, is the second most abundant rockfish in Alaska, and it supports a valuable trawl fishery. Little information is available, however, on either the biology of this species or its commercial fishery. To provide a synopsis of information on northern rockfish in Alaska, this study examined data for this species from commercial fishery observations in 1990–98 and from fishery-independent trawl surveys in 1980–99. Nearly all the commercial catch came from bottom trawling, mostly by large factory-trawlers, although smaller shore-based trawlers in recent years took an increasing portion of the catch in the Gulf of Alaska. Most of the northern rockfish catch in the Gulf of Alaska was taken by a directed fishery, whereas that of the Aleutian Islands predominantly came as discarded bycatch in the Atka mackerel fishery. In both regions, most of the catch was taken from a number of relatively small and discrete fishing grounds at depths of 75–150 m in the Gulf of Alaska and 75–175 m in the Aleutian Islands. These grounds, especially in the Gulf of Alaska, are on shallow rises or banks located on the outer continental shelf, and often are surrounded by deeper water. Five fishing grounds were identified in the Gulf of Alaska, and eleven in the Aleutian Islands. One fishing ground in the Gulf of Alaska, the “Snakehead” south of Kodiak Island, accounted for 46% of the total northern rockfish catch in this region. Analysis of the survey data generally revealed similar patterns of geographic distribution as those seen in the fishery, although some of the commercial fishing grounds did not stand out as areas of special abundance in the surveys. The surveys also found two areas of abundance that were not evident in the fishery data. Relatively few juvenile northern rockfish were caught in any of the surveys, but those taken in the Gulf of Alaska tended to occur more inshore and at shallower depths than adults. Individual size of northern rockfish was substantially larger in the Gulf of Alaska than in the Aleutian Islands according to both fishery and survey data. Analysis of age data from each region supports this, as Gulf of Alaska fish were found to grow significantly faster and reach a larger maximum length than those in the Aleutian Islands. Sex ratio in the Gulf of Alaska was nearly 50:50, but females predominated in the Aleutian Islands by a ratio of 57:43. In both regions, size of females was significantly larger than males.

A Decline in Starfish, Asterias forbesi, Abundance and a Concurrent Increase in Northern Quahog, Mercenaria mercenaria, Abundance and Landings in the Northeastern United States

The abundance of the common starfish, Asterias forbesi, fluctuates widely over time. The starfish is a predator of pre-recruit northern quahogs, Mercenaria mercenaria. During the 1990’s, starfish became scarce in Raritan Bay and Long Island Sound. Quahog populations concurrently erupted in abundance and quahog landings have risen sharply in both locations. The extensive scale of this observation would seem to imply a cause and effect; at the least, both populations may be responding differently to a large scale exogenous factor.

Northern Area Fisheries Advisory Committee 5th January, 1981

This is the report from the Northern Area Fisheries Advisory Committee meeting, which was held on the 5th January, 1981. It covers information on the review of fisheries byelaws, netting off Flimby Beach and the review of a net limitation order which was due to expire. It also includes the report by the area fisheries officer on fisheries activities which comments on river conditions and fishing for salmon, sea trout and brown trout, and the recorded numbers of fish which passed through Yearl Weir fish counter up to the 9th November. Also covered in the report is an update on Holmwrangle hatchery and the stocking numbers of salmon, sea trout and non migratory trout by the Water Authority. Finally the report adds about fish disease, biological work and the considerations of the River Caldew as a migratory fish river. 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.

Northern Area Fisheries Advisory Committee 30th March, 1981

This is the report from the Northern Area Fisheries Advisory Committee meeting, which was held on the 30th March, 1981. It covers the report by the area fisheries officer on fisheries activities. This comments on river conditions and fishing for salmon and coarse fish, migratory fish movements, and an update on Holmwrangle hatchery. Finally the report adds about stockings by the Angling Associations, and the monthy catches of salmon and sea trout for the 1980 season. 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.

Northern Area Fisheries Advisory Committee 16th June, 1981

This is the report from the Northern Area Fisheries Advisory Committee meeting, which was held on the 16th June, 1981. It includes information on fisheries in the Solway Firth, fishing licence duties and the minutes of the last meeting held on the 30th March, 1981. 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.

Northern Area Fisheries Advisory Committee 8th September, 1981

This is the report from the Northern Area Fisheries Advisory Committee meeting, which was held on the 8th September, 1981. It covers information including the consultation paper on the review of Inland and Coastal fisheries in England and Wales, and a paper on 'A National Salmon Policy'. 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.

Northern Area Fisheries Advisory Committee 12th October, 1981

This is the report from the Northern Area Fisheries Advisory Committee meeting, which was held on the 12th October, 1981. It includes the information on the recommendations of the Area Fisheries Advisory Committees on the Review of Inland and Coastal Fisheries in England and Wales, and the restructuring of rod and line fishing licence duties. It also covers the report by the area fisheries officer on fisheries activities. This comments on river conditions and fishing, migratory fish movements from Yearl Weir fish counter and an update on Holmwrangle hatchery with the summary of the fly planting programme for salmon, sea trout and brown trout. Finally the report adds about stockings carried out by the Angling Associations, fish disease and management and survey work. 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.

Northern Area Fisheries Advisory Committee 29th March, 1982

This is the report from the Northern Area Fisheries Advisory Committee meeting, which was held on the 29th March, 1982. It includes information on the Cumbrian Coastal Waters Net Limitation order, and the report by the area fisheries officer on fisheries activites from September 1981 to January 1982. The report covers information on river conditions and fishing, migratory fish movement, an update on the work at Holmwrangle Hatchery, fish disease, management and survey work and monthly salmon and sea trout catches for rod, line, nets and fixed engines for the 1981 season. 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.

Northern Area Fisheries Advisory Committee 11th October, 1982

This is the report from the Northern Area Fisheries Advisory Committee meeting, which was held on the 11th October, 1982. The report contains sections on Rod and Line Fishing Licences Format, Mink in North Cumbria, Fishing offences and prosecution, West Cumbria Water Resources, and Fisheries Activities. The section on fisheries activities is reported by the area fisheries officer and includes river conditions and fishing, migratory fish movement, Holmwrangle hatchery, and Fish mortalities/Pollutions. 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.

Northern Area Fisheries Advisory Committee 28th March, 1983

This is the report from the Northern Area Fisheries Advisory Committee meeting, which was held on the 28th March, 1983. The report contains sections on rules for fishing at Haweswater and Thirlmere, Fyke nets and otters, Whirling disease, and Fisheries Activities. The section on Fyke nets looks at the loss of at least 23 otters in fyke nets over eighteen months. The section on Fisheries Activities is reported by the area fisheries officer and includes river conditions and fishing, migratory fish movement, Holmwrangle hatchery, stocking by Angling Associations, fish mortalities and pollution. 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.