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Dosidicus Gigas (Dosidicu + giga)

Distribution by Scientific Domains
Earth and Environmental Science40%

Selected Abstracts

Synchronicity in southern hemisphere squid stocks and the influence of the Southern Oscillation and Trans Polar Index

FISHERIES OCEANOGRAPHY, Issue 4 2004
C. M. Waluda
Abstract Squid are short lived, with highly labile populations that respond rapidly to changes in environmental conditions. This makes them a good model for studying the response of recruitment processes to environmental signals. This study examines the influence of the Southern Oscillation Index (SOI) and Trans Polar Index (TPI) on the environment and abundance of six species of commercially important squid from the southern hemisphere, all linked to major current systems connected by the Antarctic Circumpolar Current: Dosidicus gigas (Southeast Pacific), Loligo vulgaris reynaudii (Southeast Atlantic), Nototodarus sloanii, N. gouldi (Southwest Pacific), Illex argentinus and L. gahi (Southwest Atlantic). All fisheries displayed a high level of inter-annual variability and a degree of synchronicity was seen to occur in the abundance of the three Pacific species. The SOI signal was reflected in the environment of each fishery, particularly in Pacific regions. Both indices are correlated with squid abundance, particularly during the early life history stages (SOI) and adult stages (TPI), suggesting some degree of latitudinal separation, with juveniles potentially influenced by environmental variability at lower latitudes and adults at higher latitudes. [source]

Nanostructured Materials: Microstructural and Biochemical Characterization of the Nanoporous Sucker Rings from Dosidicus gigas (Adv. Mater.

ADVANCED MATERIALS, Issue 4 2009
4/2009)
The cover image shows an SEM image of a squid tentacle, revealing the individual sucker rings. These toothed ringlike structures within the suckers provide additional gripping power during prey capture and handling. The background image depicts the nanoscale network of parallel tubular elements from which the rings are constructed. The structural, mechanical and biochemical properties of this wholly organic material is discussed in detail by David Kisailus, Henrik Birkedal, and co-workers on p. 401. [source]

Microstructural and Biochemical Characterization of the Nanoporous Sucker Rings from Dosidicus gigas

ADVANCED MATERIALS, Issue 4 2009
Ali Miserez
The individual toothed sucker rings of squid tentacles (highlighted in blue) provide additional gripping power during prey capture and handling. These rings comprise a nanoscale network of parallel tubular elements, as shown in the background image. The structural, mechanical, and biochemical properties of this wholly organic material are discussed in detail. [source]

Food habits of the silky shark Carcharhinus falciformis (Müller & Henle, 1839) off the western coast of Baja California Sur, Mexico

JOURNAL OF APPLIED ICHTHYOLOGY, Issue 4 2010
A. A. Cabrera-Chávez-Costa
Summary The objective of this study was to establish the trophic niche of the silky shark and to determine the ecological role of this predator in the ecosystem close to Baja California. The trophic spectrum was analyzed from samples taken during summer and autumn (2000,2002) from the fishing camps of Punta Lobos and Punta Belcher on the western coast of Baja California Sur. A total of 263 stomach contents were analyzed (143 with food; 120 empty). The index of relative importance (IRI) showed that at Punta Lobos, silky sharks fed mainly on red crabs Pleuroncodes planipes (%IRI = 83%), whereas at Punta Belcher the main food item was the jumbo squid Dosidicus gigas (%IRI = 41%), followed by chub mackerel Scomber japonicus (%IRI = 33%). According to the Levin Index (Bi), the trophic niche breadth in silky sharks is low (Bi = <0.6), which means that silky sharks are specialist predators because they mainly consume three prey types: red crab, chub mackerel, and jumbo squid. The Shannon-Wiener Index indicated that all trophic categories at Punta Belcher (0.85,1.22) had lower diversity than at Punta Lobos (0.50,1.6), because the silky shark feeds more on tropical prey found close to Punta Lobos. The Morisita-Horn Index (C,) showed an overlap in the diet between the two areas analyzed and between sexes (C, = >0.6). The juveniles and adult females did not show any overlap. In the caloric analysis of the main prey, the jumbo squid (D. gigas) contributed the most calories to the silky shark diet (76%). [source]

Comparing the effects of offset and non-offset circle hooks on catch rates of fish and sea turtles in a shallow longline fishery,

AQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 4 2010
Yonat Swimmer
Abstract 1.This study compared the catch rates of targeted dolphinfish or mahimahi (Coryphaena hippurus), and sea turtles and other fish bycatch in a shallow-set Costa Rican longline fishery using 14/0 circle hooks with and without a 10° offset. The effect of hook offset on hooking location and injury in captured sea turtles, specifically if the hooking was external, in the mouth, or in the esophagus was also evaluated. 2.Results were compared from six trips totalling 33 876 hooks with squid (Dosidicus gigas) used as bait. In total, mahimahi catch-per-unit-effort (CPUE, expressed as number caught per 1000 hooks) was similar between hook types (CPUE,52). 3.Olive ridley sea turtles (Lepidochelys olivacea) were caught on all 42 sets. In total, 640 olive ridley turtles were caught and released alive. There were no significant differences in the number of sea turtles caught between hooks with and without an offset (CPUE,19) nor between hook type and anatomical hooking location, suggesting similar levels of injury for turtles caught on each hook type. 4.These data suggest that a 10° offset on 14/0 circle hooks does not confer any selective advantages over hooks with no offset with respect to capture rates of mahimahi, sea turtles, sharks, or pelagic stingrays in a shallow set pelagic longline fishery. Copyright © 2010 John Wiley & Sons, Ltd. [source]