The Responses of Ecologically Dissimilar Populations of the Water Snake, \u3cem\u3eNatrix sipedon sipedon\u3c/em\u3e to Surface Extracts of Prey Species, With Observations on Feeding and Defense Behaviors

Observations of defensive and feeding behavior of Natrix sipedon were made in the field and in the lab. Crypticity, mimicry of poisonous snakes, striking, production of cloacal secretion and tail autonomy were defensive behaviors discussed. Feeding behaviors discussed were hunting, catching prey and tongue-flicking. Experiments were performed on the responses of snakes from ecologically dissimilar populations of N. sipedon to surface extracts of local prey species. The populations were: (1) a laboratory-reared litter of ten one-year-old snakes; (2) six wild-caught snakes from Sterchi\u27s fish hatchery in north Knoxville, Tennessee; and (3) six wild-caught and eight newborn snakes (a litter) from the Tremont area of the Great Smoky Mountains National Park. Extracts were made of prey species caught in both areas or obtained in the laboratory. Response scores were combined measure of tongue-flicks and attack latency. Group one snakes responded significantly more to goldfish (C. auratus), than to any other extract. This species has been their food for one year. Group 2 also responded more the C. auratus than to any other fish extract. The goldfish was abundant at Sterchi\u27s. However, Group 3 responded significantly more to extracts of fish that were caught near Tremont than to C. auratus. That snakes discriminated between different genera of prey was shown. The conclusion was made that wild-caught snakes respond more often to extracts of sympatric prey, presumably because these snakes have had experience eating this prey. Young of the Tremont snakes responded more to extracts of sympatric prey than to C. auratus, but the difference was not significant. This technique can be used, in conjunction with other investigations, to assess ecological relationship in an area

Role-Taking and Recidivism: A Test of Differential Social Control Theory

To assess the generality of differential social control (DSC) theory, this study examines whether the core propositions of DSC could explain recidivism among a sample of adult offenders. Overall, the results do not lend support for DSC\u27s ability to account for offenders\u27 persistence in crime. Specifically, the results reveal that only two of the five measures of role-taking, antisocial attitudes and number of prior arrests, are consistent significant predictors of recidivism. The results also indicate that measures of role-commitment are not generally related to recidivism and as a consequence, the hypothesized mediating effects of role-taking on the relationship between role-commitment and recidivism by DSC are not supported. The results also show that with the exception of age, social location measures generally are not related to recidivism and thus, definite statements on the mediating effects of DSC\u27s central concepts on this relationship could not be drawn

The database of the PREDICTS (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems) project

The PREDICTS project—Projecting Responses of Ecological Diversity In Changing Terrestrial Systems (www.predicts.org.uk)—has collated from published studies a large, reasonably representative database of comparable samples of biodiversity from multiple sites that differ in the nature or intensity of human impacts relating to land use. We have used this evidence base to develop global and regional statistical models of how local biodiversity responds to these measures. We describe and make freely available this 2016 release of the database, containing more than 3.2 million records sampled at over 26,000 locations and representing over 47,000 species. We outline how the database can help in answering a range of questions in ecology and conservation biology. To our knowledge, this is the largest and most geographically and taxonomically representative database of spatial comparisons of biodiversity that has been collated to date; it will be useful to researchers and international efforts wishing to model and understand the global status of biodiversity