Because ambient temperature strongly influences reproduction in frogs, the seasonal timing of frog calling provides a sensitive index of biotic response to climate change. Over the last century, daily temperatures increased during 5 of the 8 months key to gametogenesis in frogs and toads near Ithaca, New York (U.S.A.). Earliest dates of calling frogs recorded by Albert Hazen Wright between 1900 and 1912 near Ithaca were compared to those from the New York State Amphibian and Reptile Atlas Project for 1990-1999 for the three counties surrounding Ithaca. Four species are now calling 10-13 days earlier, two are unchanged, and none is calling later. The data suggest that climate has warmed in central New York State during this century and has resulted in earlier breeding in some amphibians-a possible first indication of biotic response to climate change in eastern North America.Resumen: Debido a que las temperaturas ambientales influyen fuertemente sobre la reproducción de ranas, el registro estacional de vocalizaciones de ranas provee un índice sensible de respuesta biótica a los cambios climáticos. Durante el siglo pasado, las temperaturas diarias incrementaron durante 5 de los 8 meses clave de la gametogénesis en ranas y sapos cercanas a Ithaca Nueva York (E.U.A.). Las fechas más tempranas de vocalizaciones de ranas registradas por Albert Hazen Wright entre 1900-1912 cerca de Ithaca fueron comparadas con aquéllas del Proyecto del Atlas de Anfibios y Reptiles del Estado de Nueva York para 1990-1999 para los tres condados de los alrededores de Ithaca. Cuatro especies están ahora vocalizando entre 10 y 13 días más temprano, dos no han cambiado y ninguna está vocalizando tarde. Los datos sugieren que el clima se ha calentado en la parte central del estado de Nueva York durante este siglo y ha resultado en reproducciones tempranas en algunos anfibios-una posible primera indicación de respuesta biótica a los cambios climáticos en Norteamérica Oriental.

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For decades conservation biologists have proposed general rules of thumb for minimum viable population size (MVP); typically, they range from hundreds to thousands of individuals. These rules have shifted conservation resources away from small and fragmented populations. We examined whether iteroparous, long-lived species might constitute an exception to general MVP guidelines. On the basis of results from a 10-year capture-recapture study in eastern New York (U.S.A.), we developed a comprehensive demographic model for the globally threatened bog turtle (Glyptemys muhlenbergii), which is designated as endangered by the IUCN in 2011. We assessed population viability across a wide range of initial abundances and carrying capacities. Not accounting for inbreeding, our results suggest that bog turtle colonies with as few as 15 breeding females have >90% probability of persisting for >100 years, provided vital rates and environmental variance remain at currently estimated levels. On the basis of our results, we suggest that MVP thresholds may be 1-2 orders of magnitude too high for many long-lived organisms. Consequently, protection of small and fragmented populations may constitute a viable conservation option for such species, especially in a regional or metapopulation context.

Tree species composition in 55 randomly selected stands from the south drainage basin of Lake George, New York, USA was analyzed by Bray-Curtis polar ordination and cluster analysis. The ordination revealed discrete groups of stand types that corresponded closely with those delineated by cluster analysis. Since the sample was unbiased, representative, and minimally distorted by the analysis, real discontinuities were presumed to exist in the vegetation. Most gaps between clusters were attributed to discontinuities in either (a) environmental factors or (b) rates of compositional change.Successional roles of the three major dominants, hemlock (Tsuga canadensis), beech (Fagus grandifolia), and sugar maple (Acer saccharum) were also assessed with the aid of ordination and cluster analysis. Each of the three dominated in one major stand cluster and these stand types were interpreted as being successionally related. Present high levels of beech and sugar maple in the study area were thought to have been promoted by logging in the late 1800's. Results of both ordination and size class analysis suggested that in many cases, sugar maple stands would change into beechhemlock stands, which would then change to hemlock. In contrast to reports from the Catskills and elsewhere, there was no evidence at Lake George that hemlock would be replaced by any other species in the absence of human disturbance. Since disturbance has been eliminated over large areas, long term increases in hemlock are predicted.

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