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Nesting is a prerequisite for breeding in a wide range of birds, and nest-sites become a key resource ultimately influencing individual fitness. In that context, reuse of nest-sites by breeding pairs has been observed in a variety of bird species. White-collared Swifts Streptoprocne zonaris constitute one example in which reuse of nest-sites from previous reproductive seasons has been reported. In this study we explored this behaviour in the main location of the species in Cuba, the natural area of Topes de Collantes (south-central Cuba), where breeding pairs occupy several natural rocky caves. We also studied nest-sites locations to identify determinants for reuse and followed nest content to quantify nesting success. During a three-year period of study, 82 nests were constructed in 67 nest-sites at three nesting colonies located at the area. Nest-sites were occupied in the four placement-location combinations at the caves: ceiling-hole, ceiling-ledge, wall-hole and wall-ledge, and were located at a height range of 0.90 to 9 m. A total of 31 nest-sites were reused at least once, which implies an incidence of nest-site reuse for the area of 46.3%. Nest-site reuse was related to characteristics of the nest-site location: reused nest-sites were less often observed at the ceiling-ledge combination as well as at the highest locations in the caves. Nesting success was measured as success in producing at least one fledgling, and was higher in reused (87.1%) than in not-reused (59.5%) nest-sites. These results confirm the existence of some benefits of nest-site reuse in the Cuban populations of the White-collared Swift, suggesting that the high quality breeding pairs might detect and select particular nest-sites to guarantee a successful breeding. This study also highlights that conservation of the caves and their natural characteristics at the natural area of Topes de Collantes is key for the Cuban populations of the species. [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jenvman.2005.07.006 Byline: Jose M. Rey Benayas (a), Enrique De La MontaA[+ or -]a (a), Josabel Belliure (a), Xavier R. Eekhout (b) Abstract: A major task related to conservation is to predict if planned infrastructure projects are likely to threaten biodiversity. In this study we investigated the potential impact of planned infrastructure in Spain on amphibian and reptile species, two highly vulnerable groups given their limited dispersal and current situation of population decline. We used distribution data of both groups to identify areas of high herpetofauna diversity, and compared the locations of these areas with the locations of the planned road, high-speed train railway and water reservoir network. Four criteria were used for this identification: species richness, rarity, vulnerability, and a combined index of the three criteria. From a total of 1441 cells of 20x20km, areas of high diversity were defined as those cells whose ranked values for the different criteria included either all species or all threatened species. The combined index provided the smallest number of cells needed to retain all threatened species (1.7 and 2.6% of the cells for amphibian and reptile species, respectively). Coincidences between these high diversity areas and cells including planned infrastructures -- denominated 'alert planning units' -- were 35.4% for amphibians and 31.2% for reptiles. Mitigation of the potential impacts would include actions such as barriers to animal access to roads and railways and ecoducts under these constructions. Our approach provides conservation authorities information that can be used to make decisions on habitat protection. A technique that identifies threats to herpetofauna before they occur is also likely to improve the chance of herpetofauna being protected. Author Affiliation: (a) Dpto. de Ecologia, Edificio de Ciencias, Universidad de Alcala, 28871 Alcala de Henares, Spain (b) Museo Nacional de Ciencias Naturales (CSIC), C/Jose Gutierrez Abascal, 2. 28006 Madrid, Spain Article History: Received 5 January 2005; Revised 16 June 2005; Accepted 21 July 2005

Effects of anthropogenic activities, including climate change, are modifying fire regimes, and the dynamic nature of these modifications requires identification of general patterns of organisms’ responses to fire. This is a challenging task because of the high complexity of factors involved (including climate, geography, land use, and species‐specific ecology). We aimed to describe the responses of the reptile community to fire across a range of environmental and fire‐history conditions in the western Mediterranean Basin. We sampled 8 sites that spanned 4 Mediterranean countries. We recorded 6064 reptile sightings of 36 species in 1620 transects and modeled 3 community metrics (total number of individuals, species richness, and Shannon diversity) as responses to environmental and fire‐history variables. Reptile community composition was also analyzed. Habitat type (natural vs. afforestation), fire age class (time since the last fire), rainfall, and temperature were important factors in explaining these metrics. The total number of individuals varied according to fire age class, reaching a peak at 15–40 years after the last fire. Species richness and Shannon diversity were more stable during postfire years. The 3 community metrics were higher under postfire conditions than in unburned forest plots. This pattern was particularly prevalent in afforested plots, indicating that the negative effect of fire on reptiles was lower than the negative effect of afforestation. Community composition varied by fire age class, indicating the existence of early‐ and late‐successional species (xeric and saxicolous vs. mesic reptiles, respectively). Species richness was 46% higher in areas with a single fire age class relative to those with a mixture of fire age classes, which indicates pyrodiverse landscapes promoted reptile diversity. An expected shift to more frequent fires will bias fire age distribution toward a predominance of early stages, and this will be harmful to reptile communities. [ABSTRACT FROM AUTHOR]

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Many lizard species show ontogenetic changes in tail colour that are coupled with changes in the antipredatory strategy. However, the ecological factors that influence the relationships between age, tail colour and antipredatory strategy remain poorly understood. In this work, we investigated how antipredatory behaviours vary according to age in Bosk’s fringe-toed lizard (Acanthodactylus boskianus), a species that shows ontogenetic changes in tail colour. First, we verified whether tail conspicuousness increases the probability of predatory attacks, by using two types of plasticine models made to mimic juveniles (red-tailed models) and adults (beige-tailed models) and distributed in a study plot where an avian predator is abundant. We found that juvenile-like red tails were more frequently attacked by predators than the less conspicuous adult-like ones. We also conducted predation simulation experiments on active lizards of different ages and compared their risk-taking and escape behaviours. Adults occurred close to potential refuges (i.e. bushes), while juveniles were more commonly observed in open microhabitats. When approached by the observer, adults rarely conducted tail displays and usually fled in a non-stop way to penetrate inside the nearest bush. However, juveniles conducted tail displays and never fled directly inside a bush. They usually stopped near the target bush and tolerated a closer approach from the observer before making the decision to take refuge inside the bush. It seems that juveniles feared the attacks of adults and avoided entering bushes occupied by adults. Repeated observations of adults acting aggressively towards juveniles provide support for this hypothesis. Overall, our findings highlight the role of tail conspicuousness in the diversion of predatory attacks from the vital parts of the body in the juveniles of Bosk’s fringe-toed lizard. They also suggest that agonistic interactions between adults and juveniles play important roles in shaping their antipredatory behaviour. [ABSTRACT FROM AUTHOR]