Growth patterns and population dynamics of Chiton articulatus (Mollusca: Polyplacophora): A multi-decade study.

The edible chiton Chiton articulatus is a commercially important mollusk found in the rocky intertidal zones of the Mexican tropical Pacific. Despite the intense harvesting in Acapulco Bay, Mexico, knowledge of its growth patterns is limited, hindering the development of effective management strategies. This study investigated the growth dynamics of C.

Interannual variability of distribution, abundance and population dynamics of the smooth hammerhead Sphyrna zygaena (Linnaeus, 1758) in the central-southeast Pacific Ocean.

This study provides information on the population dynamics of the smooth hammerhead shark Sphyrna zygaena in the central-southeast Pacific Ocean. The samples were obtained from artisanal fisheries from 2008 to 2013 to analyse cohorts, growth, mortality, abundance and recruitment using methods based on length and relative age and an inference multi-model. According to the von Bertalanffy growth model, the results indicated that the species showed from three to seven cohorts annually and slow growth (W = 57.

Association of the whale shark Rhincodon typus with the cannonball jellyfish Stomolophus meleagris.

This study describes the first record of the whale shark Rhincodon typus association with the cannonball jellyfish Stomolophus meleagris in the Gulf of California, Mexico. Whale sharks were observed swimming and feeding among swarms of jellyfish, suggesting competition and predatory behaviour given the overlap in food preferences between both species. This finding is relevant because of the species-wide distribution and the importance of these interactions, which should be considered in conservation strategies of R.

[Taxonomic and functional diversity of the bycatch fishes community of trawl fishing from Northern Gulf of California, Mexico].

The Northern Gulf of California (NGC) is a mega diverse area of high endemism with major economic interest because of the multi-specific fisheries developed, mainly shrimp. There is a lack of recent studies on bycatch fish assemblages, so during the fishing seasons from 2009-2010 and 2010-2011, on board 13 shrimp boats, 14 commercial fishing trips were performed from 5 m - 90 m in depth with a total of 119 catches. The 119 catches were analyzed to assess fish community structure using taxonomic diversity indices to detect changes in the community following the taxonomic distinctness average Δ+ and the diversity index Δ* (TAXDEST of the PRIMER v6 program).

[Determination of stress in fish community obtained from shrimp trawl fishing in Northern Gulf of California].

Bottom trawling has been considered a fishing activity that affects and modifies habitats, because of its impacts in species composition and abundance, and the alteration in the structure and function of the eco-system, that generates biodiversity loss. The Northern part of the Gulf of California has been considered a mega diverse zone with high endemism, and it is of growing interest by the international scientific community. In order to assess its potential changes in the fish community components of shrimp by-catch (FAC) in this area, a total of 119 trawls from 13 fishing boats were analyzed in Puerto Peñasco, based on 14 commercial fishing trips made within 9-90 m depth from 2010-2011.

Darkedge midshipman Porichthys analis (Batrachoidiformes: Batrachoididae), a common shrimp-bycatch fish from the Gulf of California.

Shrimp fishery bycatch of the Gulf of California constitutes a wide variety of highly unknown fish, crustacean, and mollusk species with very low or null economic value, in contrast to those of commercial interest. However, there are no studies yet on the role of these low economic valued species have in the community structure and function, together with their possible effect on commercial populations. With the aim of contributing to the knowledge of Darkedge Midshipman fish Porichthys analis, the most common waste species in this fishery, we estimated some population characteristics.

[Stomolophus meleagris fecundity (Rhizostomeae: Stomolophidae) in the Gulf of California].

The cannonball jellyfish Stomolophus meleagris is regarded as a fishery resource with high commercial value, but with scarce biological information. With the aim to generate preliminary information on reproductive aspects, the present study analyzes its fecundity, based on the estimated number of vitellogenic oocytes in the gonad; in addition, we evaluated its relationship with the jellyfish body length, diameter and wet weight; and we established the relationship of the gonadosomatic index (IGS) with the jellyfish diameter and length. For this, a total of 30 specimens were collected, measured and weighed in a monthly basis, in Las Guásimas lagoon from January to May 2006.

[Taxonomic composition and zoogeographical aspects of deep sea fishes (90-540m) from the Gulf of California, Mexico].

The Gulf of California has a high variety of ecosystems that allow different services and the fishery resources play a prominent role in its ecology, evolution and economics. Fish coastal species have been previously reported for most coastal areas, especially those species that are subject to fishing, however, little is known on the species from deep sea zones, due to sampling difficulties. We studied the deep sea fishes collected with trawl nets during three research surveys in the Gulf of California, Mexico in 2004-2005.

Population parameters of the Pacific flagfin mojarra Eucinostomus currani (Perciformes: Gerreidae) captured by shrimp trawling fishery in the Gulf of California.

Shrimp trawling fishery in the Gulf of California captures a wide variety of non-target species of fish, crustaceans, and mollusks that are relatively unknown. The Pacific flagfin mojarra Eucinostomus currani is a frequently found species in these catches, nevertheless, nothing is currently known about its population dynamics. To contribute to the knowledge on this fish species, we studied the size structure, growth, mortality, and the recruitment pattern during the 2004-2005 seasons.

[Latitudinal and bathymetric distribution of the most abundant and frequent species in the shrimp bycatch from the Gulf of California, Mexico].

The Gulf of California is one of the most mega-diverse regions in the world, for which few fishery information is available. We present here latitudinal and bathymetric distribution of the most abundant and frequent bycatch species from the Gulf of California. The samples were obtained from a total of 111 hauls taken during seven research cruises of the closed shrimp season (2002-2005-2007), and also, from research cruises made at depths up to 90 m.

[Bycatch fish species from shrimp industrial fishery in the Gulf of California, Mexico].

Bycatch fish species from shrimp industrial fishery in the Gulf of California, Mexico. The shrimp fishery in the Gulf of California is one the most important activities of revenue and employment for communities. Nevertheless, this fishery has also created a large bycatch problem, principally fish.

[Lipid variation in oocytes of the jellyfish Stomolophus meleagris (Scyphozoa: Rhizostomeae) from Las Guasimas Lagoon, Mexico, during gonadal development].

The jellyfish Stomolophus meleagris has potential for commercial exploitation but there is little information on their reproductive biology. This paper seeks to evaluate some biochemical and demographic characteristics of the species. Samples were taken monthly during 2005 and 2006.

[Taxonomic composition and zoogeographic relations of demersal in the western coast of Baja California Sur, Mexico].

The composition of demersal fish along the western coast of the State of Baja California Sur, Mexico, including the limit of the northern distribution of the ichthyofauna of the eastern tropical Pacific, is presented. The survey was carried out on four oceanographic cruises between autumn 2004 and March 2006. Of 220 species in 132 genera and 73 families, 26.

Spatial distribution and species composition of small pelagic fishes in the Gulf of California.

Traditional regionalization methods in fisheries based on provinces or major fishing areas, includes large and arbitrary grids in which basic statistics or inferences on distribution or abundance are made. We describe a method for regionalization and analysis of fishing activities for small pelagic fisheries in the Gulf of California based on spatial patterns of landing and catch data in a Geographic Information System (GIS) environment. A fisheries database from logbooks with spatial attributes from October 2002 to June 2007 was analyzed.

Decadal variability in growth of the Caribbean spiny lobster Panulirus argus (Decapoda: Paniluridae) in Cuban waters.

Annual von Bertalanffy growth parameters of the Caribbean spiny lobster (Panulirus argus) in Cuban waters were estimated from a long term study (40 years) by length-based methods ELEFAN and the new version of SLCA. Data of around 800 000 lobsters (with carapace length ranging 14 to 199mm) were randomly sampled in artificial shelters (a non selective fishing gear very common in the lobster fishery), through the field monitory program established for this species since 1963 in 14 localities of southwestern Cuban shelf. The software ELEFAN showed problems to converge in an optimal combination of the instantaneous growth coefficient (K) and the asymptotic length (Linfinity) of the von Bertalanffy equation, whereas the new SLCA software produced value estimates of K between 0.