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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.anbehav.2010.06.004 Byline: Nuria Polo-Cavia, Adega Gonzalo, Pilar Lopez, Jose Martin Abstract: The impact of alien predators on prey populations is well known by conservation biologists, but little attention has been paid to the negative effects that the introduction of exotic predators may have on native predators through competition for food. In the Iberian Peninsula, the red-eared slider, Trachemys scripta elegans, and other exotic freshwater turtles have been introduced, competing and displacing the native endangered terrapins (the European pond turtle, Emys orbicularis, and the Spanish terrapin, Mauremys leprosa). Although the nature of competitive interactions remains unclear, direct competition for food is likely to occur. Both native and invasive freshwater turtles are common predators of amphibian tadpoles. NaA[macron]ve amphibian tadpoles are known to recognize and respond to local predators with no prior experience, but tadpoles might not recognize new predatory species, since they have not shared a long evolutionary history with them. We examined the ability of four species of Iberian anuran tadpoles to recognize and respond to chemical cues from invasive and native freshwater predatory turtles. Three of the four tadpole species tested reduced their swimming activity when cues from native turtles were present in water, but not when cues belonged to exotic turtles. This inability of tadpole prey to respond innately to chemicals from introduced predatory turtles might be one of the causes that explains the displacement of native populations of Iberian terrapins by invasive exotic turtles, and may help clarify why alien predators sometimes prosper better in new habitats than locally adapted predators. Author Affiliation: Departamento de Ecologia Evolutiva, Museo Nacional de Ciencias Naturales, CSIC, Spain Article History: Received 3 February 2010; Revised 19 March 2010; Accepted 31 May 2010 Article Note: (miscellaneous) MS. number: 10-00074

Abstract: Many antipredator behaviors are mediated by the ability of prey to recognize chemical cues from predators. Adult amphibians mainly use vision to detect predators, but the ability to detect [...]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.anbehav.2006.11.032 Byline: Adega Gonzalo, Pilar Lopez, Jose Martin Abstract: Many antipredator adaptations are induced by the prey's ability to recognize chemical cues from predators and to act according to the threat level posed by that predator. However, predator recognition often requires learning by prey individuals. We tested the ability of Iberian green frog, Rana perezi, tadpoles to assess the magnitude of predation risk and adjust their behaviour by using perceived cues from a predatory snake, when this stimulus was found alone or associated with chemical alarm cues from conspecific tadpoles. Tadpoles exposed to alarm cues and the predatory snake scent together reduced their movement rates to a greater extent than when the snake scent was found alone, and reduced movement even more in the subsequent exposure to the predator snake scent alone. We also tested whether tadpoles were able to associate novel chemical cues (i.e. from an exotic nonpredatory fish) with predation risk after a simultaneous exposure with conspecific alarm cues. Tadpoles exposed to nonpredatory fish cues and alarm cues together reduced their activity levels, and reduced activity in the subsequent exposure to the fish cue alone, in a similar way as they reduced movement in the presence of predatory snake cues. Therefore, tadpoles learnt to perceive the fish cues as risky when these were previously associated with alarm cues. Predator recognition learning ability may be particularly advantageous for organisms whose environment may have a wide range of types of predators, even new exotic introduced species of predators that can affect the survival of prey. Author Affiliation: Departamento de Ecologia Evolutiva, Museo Nacional de Ciencias Naturales, CSIC, Spain Article History: Received 9 May 2006; Revised 10 August 2006; Accepted 6 November 2006 Article Note: (miscellaneous) MS. number: 8952

Abstract: In amphibians, adults and larvae have different ecological requirements that could force recently metamorphosed individuals to disperse. The presence of chemical cues of conspecifics and predators could provide information [...]

The ecology and behaviour of Amphisbaenians is poorly known due to their fossorial habits. However, amphisbaenians are often found under rocks where they thermoregulate, and probably engage in social interactions. We describe aggregations under rocks in a North African population of the little studied amphisbaenian Trogonophis wiegmanni. These observations could be used to make initial inferences about the social behaviour of this amphisbaenian. Results showed that amphisbaenians were sometimes found in pairs under the same rock. However, these aggregations were not random. Adult males were only found together with adult females, but we did not find pairs of adult males or adult females. This might suggest that there is intra-sexual intolerance, and that adult individuals of the same sex do not occupy the same rock space. Pairs of adults were more frequently found in spring than in autumn, coinciding with the mating season. Also, juvenile individuals were often found together with an adult, but juveniles tended to be more often with an adult female than with an adult male. This might indicate that juveniles are allowed to remain with their parents until they are older, which might enhance offspring fitness by providing access to high-quality habitats. [ABSTRACT FROM AUTHOR]