Report of the Inter-American Tropical Tuna Commission for the year 2004

ENGLISH: The Inter-American Tropical Tuna Commission (IATTC) operates under the authority and direction of a convention originally entered into by Costa Rica and the United States. The convention, which came into force in 1950, is open to adherence by other governments whose nationals fish for tropical tunas and tuna-like species in the eastern Pacific Ocean (EPO). Under this provision Panama adhered in 1953, Ecuador in 1961, Mexico in 1964, Canada in 1968, Japan in 1970, France and Nicaragua in 1973, Vanuatu in 1990, Venezuela in 1992, El Salvador in 1997, Guatemala in 2000, Peru in 2002, and Spain in 2003. Canada withdrew from the IATTC in 1984. The IATTC’s responsibilities are met with two programs, the Tuna-Billfish Program and the Tuna-Dolphin Program. SPANISH: La Comisión Interamericana del Atún Tropical (CIAT) funciona bajo la autoridad y dirección de una convención suscrita originalmente por Costa Rica y los Estados Unidos de América. La Convención, vigente desde 1950, está abierta a la afiliación de cualquier país cuyos ciudadanos pesquen atunes tropicales y especies afines en el Océano Pacífico oriental (OPO). Bajo esta estipulación, la República de Panamá se afilió en 1953, Ecuador en 1961, México en 1964, Canadá en 1968, Japón en 1970, Francia y Nicaragua en 1973, Vanuatu en 1990, Venezuela en 1992, El Salvador en 1997, Guatemala en 2000, Perú en 2002, y España en 2003. Canadá se retiró de la CIAT en 1984. La CIAT cumple su mandato mediante dos programas, el Programa Atún-Picudo y el Programa Atún-Delfín.

Report of the Inter-American Tropical Tuna Commission for the year 2005

ENGLISH: The Inter-American Tropical Tuna Commission (IATTC) operates under the authority and direction of a convention originally entered into by Costa Rica and the United States. The convention, which came into force in 1950, is open to adherence by other governments whose nationals fish for tropical tunas and tuna-like species in the eastern Pacific Ocean (EPO). Under this provision Panama adhered in 1953, Ecuador in 1961, Mexico in 1964, Canada in 1968, Japan in 1970, France and Nicaragua in 1973, Vanuatu in 1990, Venezuela in 1992, El Salvador in 1997, Guatemala in 2000, Peru in 2002, Spain in 2003, and the Republic of Korea in 2005. Canada withdrew from the IATTC in 1984. The IATTC's responsibilities are met with two programs, the Tuna-Billfish Program and the Tuna-Dolphin Program. SPANISH: La Comisión Interamericana del Atún Tropical (CIAT) funciona bajo la autoridad y dirección de una convención suscrita originalmente por Costa Rica y los Estados Unidos de América. La Convención, vigente desde 1950, está abierta a la afiliación de cualquier país cuyos ciudadanos pesquen atunes tropicales y especies afines en el Océano Pacífico oriental (OPO). Bajo esta estipulación, la República de Panamá se afilió en 1953, Ecuador en 1961, México en 1964, Canadá en 1968, Japón en 1970, Francia y Nicaragua en 1973, Vanuatu en 1990, Venezuela en 1992, El Salvador en 1997, Guatemala en 2000, Perú en 2002, España en 2003, y la República de Corea en 2005. Canadá se retiró de la CIAT en 1984. La CIAT cumple su mandato mediante dos programas, el Programa Atún-Picudo y el Programa Atún-Delfín.

Report of the Inter-American Tropical Tuna Commission for the year 2006

ENGLISH: The Inter-American Tropical Tuna Commission (IATTC) operates under the authority and direction of a convention originally entered into by Costa Rica and the United States. The convention, which came into force in 1950, is open to adherence by other governments whose nationals fish for tropical tunas and tuna-like species in the eastern Pacific Ocean (EPO). Under this provision Panama adhered in 1953, Ecuador in 1961, Mexico in 1964, Canada in 1968, Japan in 1970, France and Nicaragua in 1973, Vanuatu in 1990, Venezuela in 1992, El Salvador in 1997, Guatemala in 2000, Peru in 2002, Spain in 2003, and the Republic of Korea in 2005. Canada withdrew from the IATTC in 1984. The IATTC's responsibilities are met with two programs, the Tuna-Billfish Program and the Tuna-Dolphin Program. SPANISH: La Comisión Interamericana del Atún Tropical (CIAT) funciona bajo la autoridad y dirección de una convención suscrita originalmente por Costa Rica y los Estados Unidos de América. La Convención, vigente desde 1950, está abierta a la afiliación de cualquier país cuyos ciudadanos pesquen atunes tropicales y especies afines en el Océano Pacífico oriental (OPO). Bajo esta estipulación, la República de Panamá se afilió en 1953, Ecuador en 1961, México en 1964, Canadá en 1968, Japón en 1970, Francia y Nicaragua en 1973, Vanuatu en 1990, Venezuela en 1992, El Salvador en 1997, Guatemala en 2000, Perú en 2002, España en 2003, y la República de Corea en 2005. Canadá se retiró de la CIAT en 1984. La CIAT cumple su mandato mediante dos programas, el Programa Atún-Picudo y el Programa Atún-Delfín.

Report of the Inter-American Tropical Tuna Commission for the year 2007

ENGLISH: The Inter-American Tropical Tuna Commission (IATTC) operates under the authority and direction of a convention originally entered into by Costa Rica and the United States. The convention, which came into force in 1950, is open to adherence by other governments whose nationals fish for tropical tunas and tuna-like species in the eastern Pacific Ocean (EPO). Under this provision Panama adhered in 1953, Ecuador in 1961, Mexico in 1964, Canada in 1968, Japan in 1970, France and Nicaragua in 1973, Vanuatu in 1990, Venezuela in 1992, El Salvador in 1997, Guatemala in 2000, Peru in 2002, Spain in 2003, the Republic of Korea in 2005, and Colombia in 2007. Canada withdrew from the IATTC in 1984. The IATTC's responsibilities are met with two programs, the Tuna-Billfish Program and the Tuna- Dolphin Program. SPANISH: La Comisión Interamericana del Atún Tropical (CIAT) funciona bajo la autoridad y dirección de una convención suscrita originalmente por Costa Rica y los Estados Unidos de América. La Convención, vigente desde 1950, está abierta a la afiliación de cualquier país cuyos ciudadanos pesquen atunes tropicales y especies afines en el Océano Pacífico oriental (OPO). Bajo esta estipulación, la República de Panamá se afilió en 1953, Ecuador en 1961, México en 1964, Canadá en 1968, Japón en 1970, Francia y Nicaragua en 1973, Vanuatu en 1990, Venezuela en 1992, El Salvador en 1997, Guatemala en 2000, Perú en 2002, España en 2003, la República de Corea en 2005, y Colombia en 2007. Canadá se retiró de la CIAT en 1984. La CIAT cumple su mandato mediante dos programas, el Programa Atún-Picudo y el Programa Atún-Delfín.

Report of the Inter-American Tropical Tuna Commission for the year 2008

ENGLISH: The Inter-American Tropical Tuna Commission (IATTC) operates under the authority and direction of a convention originally entered into by Costa Rica and the United States. The convention, which came into force in 1950, is open to adherence by other governments whose nationals fish for tropical tunas and tuna-like species in the eastern Pacific Ocean (EPO). Under this provision Panama adhered in 1953, Ecuador in 1961, Mexico in 1964, Canada in 1968, Japan in 1970, France and Nicaragua in 1973, Vanuatu in 1990, Venezuela in 1992, El Salvador in 1997, Guatemala in 2000, Peru in 2002, Spain in 2003, the Republic of Korea in 2005, and Colombia in 2007. Canada withdrew from the IATTC in 1984. The IATTC's responsibilities are met with two programs, the Tuna-Billfish Program and the Tuna- Dolphin Program. SPANISH: La Comisión Interamericana del Atún Tropical (CIAT) funciona bajo la autoridad y dirección de una convención suscrita originalmente por Costa Rica y los Estados Unidos de América. La Convención, vigente desde 1950, está abierta a la afiliación de cualquier país cuyos ciudadanos pesquen atunes tropicales y especies afines en el Océano Pacífico oriental (OPO). Bajo esta estipulación, la República de Panamá se afilió en 1953, Ecuador en 1961, México en 1964, Canadá en 1968, Japón en 1970, Francia y Nicaragua en 1973, Vanuatu en 1990, Venezuela en 1992, El Salvador en 1997, Guatemala en 2000, Perú en 2002, España en 2003, la República de Corea en 2005, y Colombia en 2007. Canadá se retiró de la CIAT en 1984. La CIAT cumple su mandato mediante dos programas, el Programa Atún-Picudo y el Programa Atún-Delfín.

Soundings: the Newsletter of the Monterey Bay Chapter of the American Cetacean Society. 2011

Issues January - November/December 2011. (PDF contains 88 pages)

Ocean distribution of the American shad (Alosa sapidissima) along the Pacific coast of North America

We examined the incidental catches of American shad (Alosa sapidissima) taken during research cruises and in commercial and recreational landings along the Pacific coast of North America during over 30 years of sampling. Shad, an introduced species, was mainly found over the shallow continental shelf, and largest catches and highest frequency of occurrences were found north of central Oregon, along the coasts of Washington and Vancouver Island, and in California around San Francisco Bay. Migrations to the north off Washington and Vancouver were seen during spring to fall, but we found no evidence for large-scale seasonal migrations to the south during the fall or winter. The average weight of shad increased in deeper water. Sizes were also larger in early years of the study. Most were caught over a wide range of sea surface temperatures (11–17°C) and bottom temperatures (6.4–8.0°C). Abundance of shad on the continental shelf north of 44°N was highly correlated with counts of shad at Bonneville Dam on the Columbia River in the same year. Counts were negatively related to average weights and also negatively correlated with the survival of hatchery coho salmon (Oncorhynchus kisutch), indicating that survival of shad is favored by warm ocean conditions. Examining the catch during research cruises and commercial and recreational landings, we concluded that American shad along the Pacific coast have adapted to the prevailing environmental conditions and undertake only moderate seasonal migrations compared with the long seasonal migrations of shad along the Atlantic coast of North America. We suggest that the large spawning populations in the Columbia River and San Francisco Bay areas explain most of the distributional features along the Pacific coast.

Fish assemblages associated with three types of artificial reefs: density of assemblages and possible impacts on adjacent fish abundance

We evaluated the effectiveness of wooden artificial reefs (ARs) as fish habitat. Three types of ARs, made of cedar logs, broadleaf tree logs, and PVC pipes, respectively, were deployed in triplicate at 8-m depth off Maizuru, Kyoto Prefecture, Sea of Japan, in May 2004. Fish assemblages associated with each of the nine ARs were observed by using SCUBA twice a month for four years. Fish assemblages in the adjacent habitat were also monitored for two years before and four years after reef deployment. In the surveyed areas (ca. 10 m2) associated with each of the cedar, broadleaf, and PVC ARs, the average number of fish species was 4.14, 3.49, and 3.00, and the average number of individuals was 40.7, 27.9, and 20.3, respectively. The estimated biomass was also more greater when associated with the cedar ARs than with other ARs. Visual censuses of the habitat adjacent to the ARs revealed that the number of fish species and the density of individuals were not affected by the deployment of the ARs. Our results support the superiority of cedar as an AR material and indicate that deployment of wooden ARs causes no reduction of fish abundance in adjacent natural reefs.

Prosomal-width-to-weight relationships in American horseshoe crabs (Limulus polyphemus): examining conversion factors used to estimate landings

Horseshoe crabs (Limulus polyphemus) are valued by many stakeholders, including the commercial fishing industry, biomedical companies, and environmental interest groups. We designed a study to test the accuracy of the conversion factors that were used by NOAA Fisheries and state agencies to estimate horseshoe crab landings before mandatory reporting that began in 1998. Our results indicate that the NOAA Fisheries conversion factor consistently overestimates the weight of male horseshoe crabs, particularly those from New England populations. Because of the inaccuracy of this and other conversion factors, states are now mandated to report the number (not biomass) and sex of landed horseshoe crabs. However, accurate estimates of biomass are still necessary for use in prediction models that are being developed to better manage the horseshoe crab fishery. We recommend that managers use the conversion factors presented in this study to convert current landing data from numbers to biomass of harvested horseshoe crabs for future assessments.

Species-specific effects of four preservative treatments on oocytes and ovarian material of Atlantic cod (Gadus morhua), haddock (Melanogrammus aeglefinus), and American plaice (Hippoglossoides platessoides)

The lack of information concerning the preservation of ovarian material of fish species inhibits standardization of methods for determining fecundity and measuring oocytes. The effects of four preservatives (10% phosphate-buffered formalin, modified Gilson’s solution, 70% ethanol, and freezing) on ovarian material weight and oocyte size were quantified for prespawning Atlantic cod (Gadus morhua), haddock (Melanogrammus aeglefinus), and American plaice (Hippoglossoides platessoides). Effects of preservation were similar between Atlantic cod and haddock but different between Atlantic cod and American plaice for nearly all comparisons. Although all treatments affected the weight of ovarian material, freezing caused the most change and formalin caused the least. Such signif icant species-specific effects should be quantified in the calculation of life history characteristics, such as fecundity, to minimize error. This is one of few studies dedicated to evaluating the effects of preservation on oocytes and ovarian material and is the first to evaluate multiple preservatives on species.

Systematics of the North American menhadens: molecular evolutionary reconstructions in the genus Brevoortia (Clupeiformes: Clupeidae)

Evolutionary associations among the four North American species of menhadens (Brevoortia spp.) have not been thoroughly investigated. In the present study, classifications separating the four species into small-scaled and large-scaled groups were evaluated by using DNA data, and genetic associations within these groups were explored. Specifically, data from the nuclear genome (microsatellites) and the mitochondrial genome (mtDNA sequences) were used to elicit patterns of recent and historical evolutionary associations. Nuclear DNA data indicated limited contemporary gene flow among the species, and also indicated higher relatedness within the small-scaled and large-scaled menhadens than between these groups. Mitochondrial DNA sequences of the large-scaled menhadens indicated the presence of two ancestral lineages, one of which contained members of both species. This result may indicate genetic diver-gence (reproductive isolation) followed by secondary contact (hybridization) between these species. In contrast, a single ancestral lineage indicated incomplete genetic divergence between the small-scaled menhaden. These results are discussed in the context of the biology and demographics of each species.

Use of endoparasitic helminths as tags in delineating stocks of American plaice (Hippoglossoides platessoides) from the southern Gulf of St. Lawrence and Cape Breton Shelf

Endoparasitic helminths were inventoried in 483 American plaice (Hippoglossoides platessoides) collected from the southern Gulf of St. Lawrence, NAFO (North Atlantic Fisheries Organization) division 4T, and Cape Breton Shelf (NAFO subdivision 4Vn) in September 2004 and May 2003, respectively. Forward stepwise discriminant function analysis (DFA) of the 4T samples indicated that abundances of the acanthocephalans Echinorhynchus gadi and Corynosoma strumosum were significant in the classification of plaice to western or eastern 4T. Cross validation yielded a correct classification rate of 79% overall, thereby supporting the findings of earlier mark-recapture studies which have indicated that 4T plaice comprise two discrete stocks: a western and an eastern stock. Further analyses including 4Vn samples, however, indicated that endoparasitic helminths may have little value as tags in the classification of plaice overwintering in Laurentian Channel waters of the Cabot Strait and Cape Breton Shelf, where mixing of 4T and 4Vn fish may occur.

Geographical differences in the feeding patterns of red rockfish (Sebastes capensis) along South American coasts

Feeding habits and feeding strategy of red rockfish (Sebastes capensis) were studied from fish captured along most of the range of this species in coastal waters of South America. Stomach contents of 613 individuals, collected during 2003, were analyzed. Fish were obtained from six locations along the Chilean (23°S to 46°S) and Argentinian (43°S) coasts. The main prey items were Mysidacea (75.06% IRI), Osteichthyes (6.29% IRI),and Rhynchocinetes typus (6.03% IRI). Predator sex and size did not significantly affect the diet, but significant differences were found between locations. Four geographical areas, discriminated by prey occurrence and frequencies, were determined: three on the Pacific coast and one on the Atlantic coast. These areas correspond roughly with biogeographic zones described for the Chilean and southern Argentinian coasts. The feeding strategy index (FSI) indicated a specialized feeding strategy for S. capensis for most of its range. However, the FSI does not include the behaviour of a predator, and the FSI must be interpreted carefully for fishes like S. capensis that are passive ambush feeders. The abundance and availability of different prey may explain both the geographic differences in dietary composition and the specialized feeding strategy of S. capensis.