Relationship between sea surface temperatures and dolphin-associated fishing activities by the Mexican tuna fleet

Data from the Mexican purse seiner fleet operating in the eastern Tropical Pacific, for the year 1985-1990, are used to show that the fraction of surface schools of yellowfin tuna Thunnus albacares associated with dolphins (Stenella attenuata and others) increases with sea surface temperature. Possible reasons for this correlation are briefly discussed.

Seaweed industry in India

The seaweed industry in India is mainly a cottage industry and is based only on the natural stock of agar yielding red seaweeds, such as Gelidiella acerosa and Gracilaria eduli and algin yielding brown seaweed species such as Sargassum and Turbinaria. India produces 110-132 t of dry agar annually utilizing about 880-1100 t of dry agarophytes, and 360-540 t of algin from 3600-5400 t of dry alginophytes.

Tuna research and monitoring in the South Pacific

The island countries of the South Pacific have adopted a regional approach to the development and management of tuna resources, through 2 organizations based in the region - the Forum Fisheries Agency and the South Pacific Commission. Details are given of the Tuna and Billfish Assessment Programme, which involves tropical tunas and albacore.

Length-weight relationships of tuna baitfish from the Lakshadweep Islands, India

The present study reports the length-weight relationship of 11 species of baitfish from the pole and line fishery at Minicoy and S. delicatulus from the fishery at Agatti, Bangaram and Perumal Par.

Catch-effort relationship in Pacific bigeye tuna fishery

Some problems associated with fitting surplus production models to unsuitable data are discussed. This is illustrated by an application of the Schaefer, Fox and PRODFIT models to Pacific Ocean bigeye tuna (Thunnus obesus ) catch and effort data for 1952-1987, which appear to be better described by purely empirical models.

Tracking Pacific bluefin tuna (Thunnus thynnus orientalis) in the northeastern Pacific with an automated algorithm that estimates latitude by matching sea-surface-temperature data from satellites with temperature data from tags on fish

Data recovered from 11 popup satellite archival tags and 3 surgically implanted archival tags were used to analyze the movement patterns of juvenile northern bluefin tuna (Thunnus thynnus orientalis) in the eastern Pacific. The light sensors on archival and pop-up satellite transmitting archival tags (PSATs) provide data on the time of sunrise and sunset, allowing the calculation of an approximate geographic position of the animal. Light-based estimates of longitude are relatively robust but latitude estimates are prone to large degrees of error, particularly near the times of the equinoxes and when the tag is at low latitudes. Estimating latitude remains a problem for researchers using light-based geolocation algorithms and it has been suggested that sea surface temperature data from satellites may be a useful tool for refining latitude estimates. Tag data from bluefin tuna were subjected to a newly developed algorithm, called “PSAT Tracker,” which automatically matches sea surface temperature data from the tags with sea surface temperatures recorded by satellites. The results of this algorithm compared favorably to the estimates of latitude calculated with the lightbased algorithms and allowed for estimation of fish positions during times of the year when the lightbased algorithms failed. Three near one-year tracks produced by PSAT tracker showed that the fish range from the California−Oregon border to southern Baja California, Mexico, and that the majority of time is spent off the coast of central Baja Mexico. A seasonal movement pattern was evident; the fish spend winter and spring off central Baja California, and summer through fall is spent moving northward to Oregon and returning to Baja California.

History of the Atlantic Pearl-Oyster, Pinctata imbricata, Industry in Venezuela and Colombia, with Biological and Ecological Observations

In the 1500’s, the waters of Venezuela and to a lesser extent Colombia produced more natural pearls than any place ever produced in the world in any succeeding century. Atlantic pearl-oysters, Pinctata imbricata Röding 1798, were harvested almost entirely by divers. The pearls from them were exported to Spain and other European countries. By the end of the 1500’s, the pearl oysters had become much scarcer, and little harvesting took place during the 1600’s and 1700’s. Harvesting began to accelerate slowly in the mid 1800’s and has since continued but at a much lower rate than in the 1500’s. The harvesting methods have been hand collecting by divers until the early 1960’s, dredging from the 1500’s to the present, and hardhat diving from 1912 to the early 1960’s. Since the mid 1900’s, Japan and other countries of the western Pacific rim have inundated world markets with cultured pearls that are of better quality and are cheaper than natural pearls, and the marketing of natural pearls has nearly ended. The pearl oyster fishery in Colombia ended in the 1940’s, but it has continued in Venezuela with the fishermen selling the meats to support themselves; previously most meats had been discarded. A small quantity of pearls is now taken, and the fishery, which comprised about 3,000 fishermen in 1947, comprised about 300 in 2002.

Government-Industry Cooperative Fisheries Research in the North Pacific under the MSFCMA

The National Marine Fisheries Service’s Alaska Fisheries Science Center (AFSC) has a long and successful history of conducting research in cooperation with the fishing industry. Many of the AFSC’s annual resource assessment surveys are carried out aboard chartered commercial vessels and the skill and experience of captains and crew are integral to the success of this work. Fishing companies have been contracted to provide vessels and expertise for many different types of research, including testing and evaluation of survey and commercial fishing gear and development of improved methods for estimating commercial catch quantity and composition. AFSC scientists have also participated in a number of industry-initiated research projects including development of selective fishing gears for bycatch reduction and evaluating and improving observer catch composition sampling. In this paper, we describe the legal and regulatory provisions for these types of cooperative work and present examples to illustrate the process and identify the requirements for successful cooperative research.

The Oyster Industry of Eastern Mexico

Mexico has an oyster industry of substantial size, ranking about sixth in the world. In 1993, among the top ten oyster producers, Korea, Japan, the United States, China, and France ranked ahead of Mexico, while the Philippines, Australia, Canada, and New Zealand trailed it (Fig. 1). On its east coast, the species landed is the eastern oyster, Crassostrea virginica, while on its west coast C. corteziensis, C. iridescens, and the Pacific oyster, C. gigas, are landed. During the last 10-15 years, annual production often was at least 50,000 t of shelled oysters, or nearly 1.5 million bushels (Anonymous, 1995), with the great preponderance (90%) coming from a series of lagoons connecting with the Gulf of Mexico along the east coast (Fig. 2) and the remainder produced on the west coast.

Australian Vessel Performance in the East Coast Tuna Longline Fishery

A sample of daily observations on the activities of Australian vessels longlining for yellowfin tuna, Thunnus albacares, during 1987-90 was analyzed, using a production junction approach, to determine the effects of vessel characteristics and operational practices and conditions. Significant differences were found between the tuna fisheries in the northern and southern regions of the inshore yellowfin tuna fishery in the east Australian Exclusive Economic Zone. The type of vessel used, and fishing practices such as soaktime, patrolling the longline, and choice of surface water temperature were found to have significant effects on yellowfin tuna catch rates.

The Development and Decline of Hawaii's Skipjack Tuna Fishery

The pole-and-line fishery for skipjack tuna, Katsuwonus pelamis, was the largest commercial fishery in Hawaii until its decline in the 1970's and 1980's. The development and decline of the fishery were strongly affected by fish availability and marketing. A sustained drop in the availability of large fish in the mid-1970's appears to have been due in part to a sustained environmental change. Availability of large fish subsequently increased, but the fishery continued its decline owing to low profitability and lack of markets. The tuna cannery in Honolulu that fostered the fishery's expansion in the 1930's closed in 1984. Unless efforts to increase the marketf or skipjack tuna become effective, landings will probably remain at current levels of about 1,000 metric tons per year. The existing pole-and-line fleet may continue to decline with age, and the local market may eventually be supplied by other fishing methods (e.g., trolling), by new vessels, or by imports.

Tuna Fisheries in the Federated States of Micronesia, 1979-90

The management of tuna fisheries in the Federated States of Micronesia since independence in 1979 is reviewed, noting the development, seasonality, and geographic range of the fisheries. The status of stocks, including trends in catch per unit effort and the approach to setting harvest levels for the major species, are also reviewed. Future developments and management aims are discussed.

Differences in Dolphin Mortality Rates in Night and Day Sets for the U.S. Eastern Tropical Pacific Tuna Purse Seine Fishery

Because dolphins sometimes travel with yellowfin tuna, Thunnus albacares, in the eastern tropical Pacific (ETP), purse seiners use the dolphins to locate and capture tuna schools. During the process of setting the purse seine nets, dolphins often become entangled and drown before they can be released. Data for the U.S. purse seine fleet in the ETP during 1979-88 show that dolphin mortality rates in sets made during the night are higher than mortality rates in sets made during the day. Even with efforts to reduce nightset mortality rates through the use of high intensity floodlights, night set mortality rates remain higher. The data are also used to simulate a regulation on the fishery aimed at eliminating night sets and show that dolphin mortality rates would decrease.

The U.S. Gulf of Mexico Party Boat Industry: Activity Centers, Species Targeted, and Fisheries Management Opinions

In addition to providing an overview of the party boat fishery in the U.S. Gulf of Mexico, a management-oriented methodology is presented that can be used elsewhere to assess regulatory impacts. Party boat operators were interviewed to determine species targeted, percent time committed to targeting each species, and opinions on current catch restrictions. Over two-thirds of the fieet was located on the west coast of Florida. Overall, most boats targeted <5 species. Four species accounted for 90 percent of the estimated effort by party boats in the U.S. Gulf of Mexico: Snapper; Lutjanus sp.; grouper, Epinephelus sp. and Mycteroperca sp.; amberjack, Seriola dumerili; and king mackerel, Scomberomorus cavalla. Party boat effort in Texas was devoted primarily to snapper, whereas in Florida most effort was devoted to snapper and grouper collectively. Party boat operators were diverse in their opinions of management regulations in force when interviewed. Results revealed why major opposition would he expected from Texas party boat operators for red snapper bag limits and other restrictions proposed by the Gulf of Mexico Fishery Management Council.

The U.S. Gulf of Mexico Charter Boat Industry: Activity Centers, Species Targeted, and Fisheries Management Opinions

The charter boat industry in U. S. Gulf of Mexico provides access to offshore fishing opportunities for about 570,000 passengers per year on 971 boats. A 25% random sample of charter boat operators was interviewed during 1987-88 to determine species targeted, percent time committed to targeting each species, and reactions to existing catch restrictions. Three-fourths of the charter boat fleet was in Florida, 13% in Texas, 5% in Louisiana, 4% in Alabama, and 2% in Mississippi. Responses were diverse regarding species focus within the region. Species of dominant importance included groupers, Epinephelus sp. and Mycteroperca sp. (Fla.); snapper, Lutjanus campechanus (Ala., Fla., Miss., and La.); king mackerel, Scomberomorus cavalla (Miss., Tex., Ala. and Fla.); spotted seatrout, Cynoscion nebulosus (Tex. and La.); and red drum, Sciaenops ocellatus (Tex. and La). Catch restrictions were generally supported with higher levels of opposition to restricted high effort fish and/or one fish or closed fishery limits.