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In Mexico, several species of fishes are being affected by anthropogenic changes in rivers and streams. In order to understand the potential impacts of human activities on Poeciliopsis fasciata, we examined characteristics of the Río Salado in Puebla, Mexico that were associated with the presence of P. fasciata. Fish were observed in the river in March 2007 and from November 2007 through February 2008, but not from April 2007 through October 2007. The dynamic nature of the Río Salado likely influences the presence of P. fasciata, as evidenced by our finding fish in the study area only during a limited period during the year. The distribution of P. fasciata along the Río Salade is clearly influenced by factors related to the permanence of water, the chemical nature of the water (salinity, dissolved oxygen), and the presence of vegetation. Our results suggest that the presence of salt factories ("salineras") along the RIo Salado have the potential to influence the presence of P. fasciata, either through changes in water flow or salinity. [ABSTRACT FROM AUTHOR]

We examined within-pond oviposition site selection by two spring-breeding amphibians, the spotted salamander (Ambystoma maculatum) and the wood frog (Rana sylvatica), in two small ponds in central Ohio. Both species deposited their eggs in a non-random pattern within the ponds, ovipositing closer to shore and in shallower water than would be expected by chance. Rana sylvatica eggs were laid in warmer sites that had lower dissolved oxygen levels than random sites. Ambystoma maculatum egg masses tended to be fairly isolated from other A. maculatum egg masses, whereas R. sylvatica egg masses were highly aggregated. [ABSTRACT FROM AUTHOR]

Presents information on a study which examined the diet of a population of river otters that were re-introduced into the Verde River valley in north-central Arizona. Description of the study site; Methodologies of the study; Results of the study.