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Fed and starved Fundulus heleroclitus specimens were exposed for 30 days to sublethal copper concentrations (800 mu g Cu2+/L).The accumulation of copper and histopathological effects on the liver and gills were studied. In both fed and starved specimens, the liver showed a progressive copper accumulation during the experimental period (from 2 to 30 days), with higher levels of copper in the liver of starved fish. Copper accumulation was also detected in the gills, and the specimens exposed to copper for 15 to 30 days (both fed and starved) showed significant differences (P < 0.005) with respect to thecontrol group and the 2-day treated fishes. The main histopathological alterations were: vacuolization of hepatic parenchyma, desquamation of gill epithelia, lamellar telangiectasia, as well as hepatic and branchial necrosis. The results of this paper provide evidence that the nutritional status of the fish has great importance in modifying its response to sublethal copper effects. [ABSTRACT FROM AUTHOR]

This paper presents a complete list of hermatypic coral species, analyzes the biodiversity levels and describes the biogeographic patterns of the group in the Mexican Pacific. The coral fauna of the MexicanPacific consists of 23 species, which makes this region one of the highest in terms of specific richness within the tropical eastern Pacific. In general, the species are grouped in faunistic units that correspond to the traditional zoogeographic provinces recognized in the region. There is no evidence of effective biogeographic barriers throughout the Mexican Pacific region. Local extinction events, likely caused by the narrow distribution of some species, and perhaps due to the type and frequency of transpacific colonizations, modify the normalprocesses of community succession, causing the Mexican Pacific to bea highly dynamic zone in terms of its coral fauna. [ABSTRACT FROM AUTHOR]

The longline is the most common fishing gear used to catch pelagic fish species. It consists of a principal line or mother line from which secondary lines with hooks hang. This fishing gear has demonstratedits efficiency to catch tuna, shark and billfish. The relative specific selectivity, according to some authors, seems to be influenced byfactors like fishing strategy, horizontal and vertical species distribution, and the kind and size of bait. In this paper, a practical method to estimate hook operating depth is proposed, taking into consideration the catenary line formed by the mother line in each section. This estimate was validated with data obtained by means of a CTD meter placed at the same depth as the hooks during the longline operation. Moreover, an analysis of the species composition of the catch at each hook depth was performed. The results indicate that there is a difference of more than 30 m between operating depths in each section. Likewise, significant differences (at level a = 0.05) among catches ateach operating level were observed. [ABSTRACT FROM AUTHOR]

The objectives of this paper were to present a taxonomic list and determine the richness and local distribution of the species of the phylum Echinodermata at Bahia de La Paz. An exhaustive review of published material on this subject from the last century to 1995 was made, and complemented with an analysis of specimens collected in the zone and included in the UNAM and UABCS collections. After the taxonomic information was analyzed and validated, it was found that, at Bahia de La Paz, 92 echinoderm species have been recorded: 21 species of the class Asteroidea, 18 of the class Ophiuroidea, 26 of the class Echinoidea and 27 of the class Holothuroidea. This level of echinoderm species richness is one of the highest known for the Pacific coast of Mexico and the tropical eastern Pacific region; 41% of the species have been found only in one zone of the bay and just 7% inhabit the whole site. The high level of species richness of Bahia de La Paz might be explained as a combination of a large sampling effort in the zone, together with the incidental occurrence of several species, the locationof the bay (near a zoogeographical transition zone) and the variety of local habitats. [ABSTRACT FROM AUTHOR]

The relationship between the directional spectrum of sea surface waves and the optical or digital diffraction pattern is well established. Barber (1954) proved that the wave direction can be estimated from the diffraction pattern of a photographic image. This work presents the analysis of aerial sea surface images. The diffraction pattern or power spectrum of each image was obtained to determine the directional spectrum. The technique applied to the sea surface images obtained 12 May, 1993 showed that the waves presented a predominant direction to 65 deg.N and an origin in the 250 deg.SW range. The 200 to 12 m wavelengths were the most frequently found. The implementation and design of the photographic system is described in this paper. We discuss its applicability and limitations, as well as the potential this method has in oceanography. [ABSTRACT FROM AUTHOR]