Predatory fishes, such as tunas, billfishes, and sharks, coexist in pelagic regions of the tropical oceans. In situ experiments have revealed horizontal and vertical movement patterns for different pelagic species, but the influence of the biotic environment on movement behaviour has not been studied. In this paper, we propose a simple model in which the movement behaviour of these fishes is dr...

Fishes may show sexual dimorphism according to their reproductive strategies. In some species, this differentiation is already well known. However, with the findings obtained from recent studies, the number of species for which sex can be determined without dissection has increased. Thus far, the presence of external secondary sexual characteristics in Hoplias aimara, a very well-studied specie...

cutaneous lesions in fishes due to viral, bacterial, parasitic, mechanical and chemical agents are very common, leading to severe infection and high mortality. the aim of this research was to investigate the effect of long term bath of zinc sulfate (15 and 23 ppm), healing of cutaneous lesions caused by surgical incision in carps. in this study, 210 carps were disinfected by 3% salt solution fo...

Large-bodied reef fishes represent an economically and ecologically important segment of the coral reef fish assemblage. Many of these individuals supply the bulk of the reproductive output for their population and have a disproportionate effect on their environment (e.g. as apex predators or bioeroding herbivores). Large-bodied reef fishes also tend to be at greatest risk of overfishing, and t...

1. The retinas of all marine fishes so far examined except the Labridae, and of all terrestrial vertebrates contain the rhodopsin system alone; those of fresh water fishes the porphyropsin system alone. In the present paper the visual systems of a number of euryhaline fishes are examined-fishes capable of existence in a wide range of salinities, though usually restricted in spawning either to t...

Physiological studies of larval fishes have lagged far behind those of adults, yet offer tremendous opportunities for expanding our knowledge of the basic biology of both marine and freshwater fishes. Physiological studies of larval fishes can also improve research and management in areas of applied science, such as aquaculture, fisheries, and environmental assessment. Additionally, larval fish...

The relationship between the Chondrichthyes (cartilaginous fishes), the Actinopterygii (ray-finned fishes), and the piscine Sarcopterygii (lobe-finned fishes) and how the Tetrapoda (four-limbed terrestrial vertebrates) are related to these has been a contentious issue for more than a century. A general consensus about the relationship of these vertebrate clades has gradually emerged among morph...

INTRODUCTI9N THERE ARE MANY REPO~TS of luminous fishes, all of which, in earlier days, were taken from the deep seas. Luminous organs were found on the sides of the bodies, on the barbels, or on the antennae. In ourward 'appearance these fishes were strangely shaped and feebl y developed, with soft bones and loose muscles, and it was assumed that such 'unusual fishes belonged exclusively to the...

Beach seines are widely used to estimate the density and species richness of fishes in estuaries. We evaluated the causes and extent of bias in estimates from seines using a series of field experiments in small estuaries in southern California, USA. Seining in spatially paired areas that were either enclosed by block nets or not, revealed that seines used without block nets underestimated densi...

In theHawaiianArchipelago, shelter-dependent juvenile stages ofmany reef fishes and their coral habitats are increasingly put at risk by multiple anthropogenic stressors (e.g. overfishing and habitat loss, coral bleaching and sedimentation, respectively).We assessed coral bleaching (to identify relative susceptibility among growth forms) and the use v. availability of structurally complex and s...