Electrofishing adequacy was tested as a technique to obtain quantitative data of coastal stream fish populations and communities in the Southeast of Brazil. Seven field trips, between July/94 and July/ 95, were done in 5 localities of the Ubatiba fluvial system (Maricá, RJ). Seventeen species, among the 22 collected, had their numbers estimated through the Zipping method, the model used to test...

BACKGROUND Ferox Trout are large, long-lived piscivorous Brown Trout (Salmo trutta). Due to their exceptionally large size, Ferox Trout are highly sought after by anglers while their life-history strategy, which includes delayed maturation, multiphasic growth and extended longevity, is of interest to ecological and evolutionary modelers. However, despite their recreational and theoretical impor...

The potential for size-selective fishing to cause contemporary evolutionary changes in adaptive traits has attracted considerable interest in recent years (Jørgensen et al. 2007; Kuparinen and Merilä 2007). Fishing-induced selection has been identified as having the capacity to change various life-history traits as well as morphological, behavioral, and physiological traits (reviewed by Polican...

The dynamics of competing populations are investigated using discrete non-linear models with age structure. Necessary and sufficient stability conditions for the coexistence equililbrium between two competing non-interbreeding species are developed. An extension of this result shows that coexistence, which is not necessarily stable, occurs in terms of a simple geometric rule on a two dimensiona...

The present study sought to uncover what constraints shape the early development of the perceptual–motor skill of catching, and how intrinsic (i.e., movement possibilities) and extrinsic constraints (i.e., object speed imposes temporal precision) impinge on the perception of whether or not a moving object affords catching. Thirty-five infants (with different preferred catching tendencies) betwe...

STUDY OBJECTIVE To investigate the utility of capture-recapture methods to estimate prevalence of subjects with alcohol related disorders using multiple incomplete lists. DESIGN This was a cross sectional study of alcohol related disorders in a large community. SETTING During 1997 identified cases with known alcohol related disorders were independently flagged by four sources (self help vol...