Effect of type of otolith and preparation technique on age estimation of larval and juvenile spot (Leiostomus xanthurus)

Otoliths of larval and juvenile fish provide a record of age, size, growth, and development (Campana and Neilson, 1985; Thorrold and Hare, 2002). However, determining the time of first increment formation in otoliths (Campana, 2001) and assessing the accuracy (deviation from real age) and precision (repeatability of increment counts from the same otolith) of increment counts are prerequisites for using otoliths to study the life history of fish (Campana and Moksness, 1991). For most fish species, first increment deposition occurs either at hatching, a day after hatching, or after first feeding and yolksac absorption (Jones, 1986; Thorrold and Hare, 2002). Increment deposition before hatching also occurs (Barkmann and Beck, 1976; Radtke and Dean, 1982). If first increment deposition does not occur at hatching, the standard procedure is to add a predetermined number to increment counts to estimate fish age (Campana and Neilson, 1985).

Review of the California Trawl Fishery for Pacific Ocean Shrimp, Pandalus jordani, from 1992 to 2007

The commercial bottom trawl fishery for Pacific ocean shrimp, Pandalus jordani, or pink shrimp, operates mostly off the west coast of the contiguous United States. The California portion of the fishery has not been thoroughly documented or reviewed since the 1991 fishing season, despite its fluctuating more during the last 16 years (1992–2007) than at any other period in its 56-year history. We used fishery-dependent data, California Department of Fish and Game commercial landing receipts and logbook data, to analyze trends and review the California pink shrimp trawl fishery from 1992 to 2007. In particular, we focus on the most recent years of the fishery (2001–07) to highlight the gear developments and key management measures implemented in the fishery. The fishery is primarily driven by market conditions and is highly regulated by both state and Federal management agencies. Several key regulatory measures implemented during this decade have had significant effects on the fishery. For example, the requirement of a Bycatch Reduction Device on trawl nets targeting pink shrimp was approved in 2001 and has greatly reduced levels of finfish bycatch. Fishery production has declined, particularly in recent years, and may be attributed to decreased market prices, followed by reduced fishermen participation; both of which are related to changes in the processing sector and demand for the product.

Elasmobranch Landings for the Portuguese Commercial Fishery From 1986 to 2001

Portuguese commercial elasmobranch landings were analyzed for the period 1986–2001. An average of 5,169 (± 795 t) were landed yearly, representing 18 families, 29 genera, and 34 confirmed species. However, annual landings for the fishery generally decreased over time, with a corresponding increase in price per kilogram. The most important group, Raja spp., accounted for 33% of the landings or 26,916 t. They were followed by Centroscymnus coelolepis, Scyliorhinus spp., Centrophorus granulosus, and Centrophorus squamosus (accounting for 12%, 12%, 11%, and 9% of the landings, respectively). In the absence of CPUE data, the comparative trends of landings and price were employed as an indicator of the “status” of specific elasmobranch species. Raja spp., Centrophorus granulosus, Mustelus spp., Torpedo spp., and Squatinidae displayed indications of possible overexploitation, and they merit the focus of future research.

The Demand for Eastern Oysters, Crassostrea virginica, from the Gulf of Mexico in the Presence of Vibrio vulnificus

California, in response to health concerns, initiated a program on 1 March 1991 which required anyone selling eastern oysters, Crassostrea virginica, from the Gulf of Mexico area to notify potential consumers that there was a risk in consuming them raw. This mandatory warning, followed shortly thereafter by a similar warning in other states, including Louisiana and Florida, received extensive press cover-age throughout the country and particularly in the Gulf area. This paper examines the extent to which the demand for Gulf-area oysters has been reduced as a result of mandatory warning labels and negative publicity. In general, the results suggest that since 1991 the “summer” dockside price has been reduced by about 50% as a result of warning labels and associated negative publicity, while the “winter” dockside price has been reduced by about 30%.

Gunnislake Annual Report 2001

This is the Gunnislake Fish Counter, Annual Report 2001 produced by the Environment Agency South West Region on March 2002. The report presents the daily upstream counts of migratory salmonids recorded on the River Tamar at Gunnislake Weir fish counting station (SX 435 713) situated in 2001. Data contained within this report covers the period of the commercial migratory salmonid net buy-back scheme and the National Spring Salmon Byelaws. The fish counter at Gunnislake is a resistivity based system (Logie 2100A – Aquantic limited) and is installed in the fish pass on the Cornish bank of the River Tamar at the head of the tide. The minimum salmon count for 2001 was 3138. The 2001 upstream count for sea trout was 7503. The run pattern observed for salmon and sea trout in 2001 was generally consistent with that of previous years.

Restormel Annual Report 2001

This is the Restormel Fish Counter, Annual Report 2001 produced by the Environment Agency South West Region on March 2002. The report presents the daily upstream counts of migratory salmonids on the River Fowey at Restormel Weir fish counting station (SX 107 613) in 2001. The counter data covers the period of the commercial salmonid net buy back scheme and the national spring salmon byelaws. These reduce the commercial netting season for salmon and sea trout to between 16 June and 31 August. The fish counter at Restormel is installed on a crump sectioned weir on the River Fowey. The fish counter is a resistivity based system and operates over all three channels of the weir. 2001 was a good year for large sea trout. The number of returning large sea trout was above average in April, May, June and July and equal to or higher than the previous recorded maximum in those months. The main run of small sea trout occurred at a similar time to previous years with the highest numbers of fish entering the Fowey during June and July.

Stillwaters monitoring programme. Summary results 2001 and 2002

This is the Stillwaters monitoring programme. Summary results 2001 and 2002 from the Environment Agency North West. Until January 2001 the South Area Stillwaters Sampling Programme consisted of a rolling programme where five to six stillwaters were sampled three times a year (spring, summer and autumn). However, this method was not yielding the water quality information required for long term monitoring. Local weather conditions influence short-term water quality events, e.g. algal blooms, nutrient consumption, stratification, super-saturation etc, so results from one day sampling could only be regarded as individual ‘spot’ samples. Therefore year-on-year comparisons could not be made. It was decided that long-term water quality monitoring of the stillwaters would benefit more from sampling nutrient abundance over winter months. This would give an insight into the carry-over of nutrients available for algal growth the following year and so year-on-year productivity could be assessed. Survey results shown in this report were from: The Mere, Rostherne Mere, Melchett Mere, Tabley Mere, Tatton Mere, Hatchmere, Oak Mere, Black Lake, Chapel Mere, Bar Mere, Oss Mere, Marbury Big Mere, Comber Mere and Betley Mere.

2001 annual report on fisheries in the North West

This is the 2001 annual report on fisheries in the North West produced by the Environment Agency North West in 2002. This report has four main aims: to inform the Agency’s customers of developments within the Agency, to inform the Agency’s customers of the work carried out by the Agency, to publish information on the performance of fisheries and the Fisheries Department, and to be a source of future reference. The fisheries service is funded in the main by a mixture of rod licence income and government grant-in-aid. The latter has declined substantially since the mid 1990’s and we are increasingly reliant on licence income to fund fisheries work. The environment agency had managed to use some of this money to fund their Urban Fisheries Development Programme, (UFDP). This is aimed at delivering new or improved fisheries in areas where demand for fishing is high, but where available fisheries are few in number or of poor quality. This work is dependent on good co-operation with local angling clubs, councils and other interests.

Salmon stocks and fisheries in England and Wales, 2001. Preliminary assessment prepared for ICES, April 2002

This report presents a preliminary assessment of the state of salmon stocks and fisheries in England and Wales in 2001 to assist ICES in providing scientific advice to NASCO and to provide early feedback to fishery managers and anglers. The chief indicators of the state o f salmon stocks are normally the catches taken by rod and net fisheries. However, in 2001 angling was affected by the outbreak of foot and mouth disease (FMD), which restricted angling opportunities and access to rod fisheries in many parts of the country for lengthy periods. It is impossible to quantify the impact that FMD had on rod catches, although these were undoubtedly significantly reduced; net fisheries were unaffected by FMD. The declared salmon catch for 2001 (including those fish released alive by anglers) is provisionally estimated at 209 tonnes, representing some 57,000 fish, and comprising 153 tonnes (-43,000 fish) by nets and fixed engines and 56 tonnes (-14,000 fish) by rods. For direct comparison with previous years, it should be noted that the declared catch prior to the issue of a second reminder was about 49 tonnes (see below). An estimated 26 tonnes (43%) of the rod catch was released alive. These figures do not take account of catches of salmon which go unreported (including those taken illegally), and it is estimated that there may have been a total of 33 tonnes of additional fish caught in 2001; approximately 15% of all fish killed.

River Eden RHS and geomorphology evaluation. Final report October 2001

This is the River Eden RHS and geomorphology evaluation: Final report October 2001 produced by the Environment Agency North West in 2001. This report analysed the River Habitat Survey (RHS) and geomorphology data to evaluate the level of habitat quality and the geomorphological characteristics of the River Eden and sub-catchments. RHS data and geomorphological assessment data was collected within the study areas by CEH and Fluvial Environmental Services Ltd. The River Eden and its sub-catchments are being considered as a Special Area for Conservation (SAC) due to the presence of habitat types and species, which are rare or threatened within Europe. The purpose of the project is to provide an overview of the state of the catchment in terms of river habitats and geomorphological processes in order to aid the derivation of sound management for this proposed SAC.The aim of this report was to determine the state of the environment within the Eden and sub-catchments and identify the main pressures on the system in order to derive sound management options.

Breeding populations of seabirds in California, 1989-1991. Volume I - population estimates

In 1989-1991, the U.S. Fish and Wildlife Service surveyed breeding populations of seabirds on the entire California coast. This study was sponsored by the Minerals Management Service in relation to outer continental shelf oil and gas leasing. At 483 nesting sites (excluding terns and skimmers in southern California), we estimated 643,307 breeding birds of 21 seabird species including: 410 Fork-tailed Storm-petrel (Oceanodroma furcata); 12,551 Leach's Storm-petrel (O. leucorhoa); 7,209 Ashy Storm-petrel (O. homochroa); 274 Black Storm-petrel (O. melania); 11,916 Brown Pelican (Pelecanus occidentalis); 10,037 Double-crested Cormorant (Phalacrocorax auritus); 83,394 Brandt's Cormorant (P. penicillatus); 14,345 Pelagic Cormorant (P. pelagicus); 888 Black Oystercatcher (Haemotopus bachmani); 4,764 California Gull (Larus californicus); 61,760 Western Gull (L. occidentalis); 2,838 Caspian Tern (Sterna caspia) (excluding southern California); 3,550 Forster's Tern (S. forsteri) (excluding southern California); 272 Least Tern (S. albifrons) (excluding southern California); 351,336 Common Murre (Uria aalge); 15,470 Pigeon Guillemot (Cepphus columba); 1,821 Marbled Murrelet (Brachyramphus marmoratus); 1,760 Xantus' Murrelet (Endomychura hypoleuca); 56,562 Cassin's Auklet (Ptychoramphus aleuticus); 1,769 Rhinoceros Auklet (Cerorhinca monocerata); and 276 Tufted Puffin (Fratercula cirrhata). The inland, historical or hybrid breeding status of American White Pelican (P. erythrorynchus), American Oystercatcher (H. palliatus), Heermann's Gull (L. heermanni), Ring-billed Gull (L. delawarensis), Glaucous-winged Gull (L. glaucescens) and Black Tern (Chlidonias niger) are discussed. Estimates for Gull-billed Tern (S. nilotica), Royal Tern (S. maxima), Elegant Tern (S. elegans) and Black Skimmer (Rhynchops niger) will be included in the final draft of this report. Overall numbers were slightly lower than reported in 1975-1980 surveys (summarized in Sowls et al. 1980. Catalog of California seabird colonies. U.S. Dept. Int., Fish Wildl. Serv., Biol. Serv. Prog., FWS/OBS 37/80). Recent declines were found or suspected for Fork-tailed Storm-petrel, Leach's Storm-petrel, White Pelican, Black Tern, Caspian Tern, Least Tern, Common Murre and Marbled Murrelet. Recent increases were found or suspected for Brown Pelican, Double-crested cormorant, California Gull, Western Gull, Forster's Tern and Rhinoceros Auklet. Similar numbers were found for other species or trends could not be determined without additional surveys, studies and/or more in-depth comparisons with previous surveys. The status of terns and skimmers in southern California has not yet been finalized.