Landscape features of anthropogenic or natural origin can influence organisms' dispersal patterns and the connectivity of populations. Understanding these relationships is of broad interest in ecology and evolutionary biology and provides key insights for habitat conservation planning at the landscape scale. This knowledge is germane to restoration efforts for the New England cottontail (Sylvilagus transitionalis), an early successional habitat specialist of conservation concern. We evaluated local population structure and measures of genetic diversity of a geographically isolated population of cottontails in the northeastern United States. We also conducted a multiscale landscape genetic analysis, in which we assessed genetic discontinuities relative to the landscape and developed several resistance models to test hypotheses about landscape features that promote or inhibit cottontail dispersal within and across the local populations. Bayesian clustering identified four genetically distinct populations, with very little migration among them, and additional substructure within one of those populations. These populations had private alleles, low genetic diversity, critically low effective population sizes (3.2–36.7), and evidence of recent genetic bottlenecks. Major highways and a river were found to limit cottontail dispersal and to separate populations. The habitat along roadsides, railroad beds, and utility corridors, on the other hand, was found to facilitate cottontail movement among patches. The relative importance of dispersal barriers and facilitators on gene flow varied among populations in relation to landscape composition, demonstrating the complexity and context dependency of factors influencing gene flow and highlighting the importance of replication and scale in landscape genetic studies. Our findings provide information for the design of restoration landscapes for the New England cottontail and also highlight the dual influence of roads, as both barriers and facilitators of dispersal for an early successional habitat specialist in a fragmented landscape.

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The authors analyzed the spellings of 179 U.S. children (age = 3 years, 2 months-5 years, 6 months) who were prephonological spellers, in that they wrote using letters that did not reflect the phonemes in the target items. Supporting the idea that children use their statistical learning skills to learn about the outer form of writing before they begin to spell phonologically, older prephonological spellers showed more knowledge about English letter patterns than did younger prephonological spellers. The written productions of older prephonological spellers were rated by adults as more similar to English words than were the productions of younger prephonological spellers. The older children s spellings were also more wordlike on several objective measures, including length, variability of letters within words, and digram frequency.

The degree that hunting may influence game populations depends on whether hunting mortality is additional to (additive) or replaces (compensatory) natural-caused mortalities. In response to limited information on the effects of exploitation on eastern cottontail (Sylvilagus floridanus (J.A. Allen, 1890)) populations within Cape Cod National Seashore (CCNS), we initiated an investigation of cause-specific mortality using transmitter-equipped cottontails in hunted and nonhunted areas as a way to examine the additive versus compensatory aspect of hunting. Predation caused >70% of all deaths, whereas hunting caused 10% of deaths in the areas sampled. Survival rate was substantially lower among hunted sites (0.05) than at nonhunted sites (0.19) during the winter-spring of year 1, but there was no difference between hunted (0.33) and nonhunted (0.40) sites during year 2. Lower survival in year 1 was likely due to deep and persistent snow that increased vulnerability to predation and probably reduced the prospect for hunting mortalities to be compensated by reductions among other mortality factors. However, at least partial compensation apparently occurred during year 2 when winter weather was less severe. Cottontails at CCNS are near the northern edge of their geographic range and therefore may be ultimately limited by severe weather conditions. Compared with predation, we do not believe that the current levels and distributions of hunting influence cottontail populations at CCNS. Résumé :La mesure dans laquelle la chasse peut affecter les populations d'espèces sportives n'est pas la même lorsque la mortalité due à la chasse s'ajoute à la mortalité due aux causes naturelles (mortalité additive) et lorsqu'elle la remplace (mortalité compensatoire). Pour corriger le peu d'information disponible sur les effets de l'exploitation sur les populations de lapins à queue blanche (Sylvilagus floridanus (J.A. Allen, 1890)) dans la plage nationale de Cape Cod (CCNS), nous avons mis au point une recherche de la mortalité en fonction de ses causes spécifiques à l'aide de lapins munis d'émet-teurs dans des zones de chasse et des zones interdites à la chasse, dans le but de comparer les aspects additifs et compensatoires de la chasse. Dans les zones échantillonnées, la prédation cause >70 % de toute la mortalité, alors que la chasse en est responsable de 10 %. La survie était nettement inférieure dans les zones de chasse (0,05) que dans les zones interdites à la chasse (0,19) durant l'hiver et le printemps de l'an 1, mais il n'y avait aucune différence entre les zones de chasse (0,33) et les zones sans chasse (0,40) durant l'an 2. La survie réduite durant l'an 1 est vraisemblablement due à la neige profonde et persistante qui a augmenté la vulnérabilité à la prédation et a probablement réduit la possibilité que la mortalité due à la chasse soit compensée par des réductions des autres facteurs de mortalité. Cependant, il s'est produit une compensation, au moins partielle, durant l'an 2 quand l'hiver a été moins rigoureux. Les lapins au...