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Many animals exhibit circadian variation in behavior; thus, studying nocturnal behavior is important to fully understand species activity patterns. The nocturnal behavior of Asian elephants, and specifically calves, has received little previous study. We carried out observational study of the nocturnal behavior of orphaned Asian elephant calves at three age groups: 'infant' (0-24 months), 'young juvenile' (25-36 months) and 'old juveniles' (over 36 months). Project aims were to build a nocturnal activity budget, to investigate key age differences, and whether calves exhibited synchronous behavior patterns. We carried out focal animal sampling and instantaneous group scan sampling on 34 calves for 18 nights using an infra-red camera. Focal results indicated that calves spent the highest percentage of scans in lying rest (46.2%) and feeding (28.4%). There was no significant difference between lying rest in the three age groups. Calves spent the majority of time within 5 m of their nearest neighbor, with infants remaining in closest proximity to conspecifics compared to older calves. Synchronous behavior could not be proved statistically but two distinct lying rest periods between 2300 and 0100, and 0330 and 0530, were noted. We found that calves spent more time in lying rest than previously observed in adult elephants. Activity patterns observed suggest that the orphaned group behavior is similar to that reported in the wild and captive zoological collections, and appears to be in concordance with 'natural' behavior patterns, a defining feature of animal welfare. This research provides valuable data as a preliminary study. [ABSTRACT FROM AUTHOR]

Behavioral responses of Risso's dolphins ( Grampus griseus) to whale watching vessels were studied off Pico Island, Azores. Dolphin behavior was studied from a land-based lookout, enabling observations of groups in the absence and presence of vessels. The number of whale watching vessels showed a clear seasonal pattern, dividing the whale watching period into a low season and a high season. During the low season, Risso's dolphins rested mainly in the morning and afternoon. During the high season, Risso's dolphins rested less and did so mainly at noon, when the number of active vessels was lowest. Data analysis using a generalized additive mixed model indicated that this change in resting behavior was associated with vessel abundance. When more than five vessels were present, Risso's dolphins spent significantly less time resting and socializing. During the high season, this vessel abundance was exceeded during 20% of observation days. While we cannot be sure that the observed changes in behavior have fitness consequences for Risso's dolphins, reduced resting and socializing rates can have negative impacts on the build-up of energy reserves and on reproductive success. We suggest the adoption of precautionary management measures to regulate the timing and intensity of whale watching activities. [ABSTRACT FROM AUTHOR]

Indoor resting and human-landing mosquito collections were conducted at selected localities in Kolkata, India to determine resting and host-seeking behavior, night biting activity, seasonal distributions and malaria infection rates. During a two-year study (2006–2007), 5123 and 1716 female mosquitoes were captured in indoor-resting and human-landing collections, respectively, from two types of residences (brick built rooms, temporary huts). Regression analysis demonstrated that the abundance of indoor resting An. stephensi was positively correlated with ambient temperature and relative humidity. The average duration of the gonotrophic cycle for laboratory-reared An. stephensi was about 4 days. Average proportion of parous An. stephensi, daily survival and daily mortality rates were 46%, 82% and 18%, respectively. Plasmodium vivax sporozoite infections were detected in the salivary glands of two wild-caught An. stephensi (sporozoite rate 2.2%) and one An. annularis (sporozoite rate 1.5%). No P. falciparum infections were detected. Oocyst infections were observed in one An. annularis mosquito (oocyst rate 1.5%). [ABSTRACT FROM AUTHOR]

We investigated habitat use and diversity of waterbirds at one of the coastal and satellite lagoons around Lake Biwa, which is a registered wetland of the Ramsar Convention in Japan. To evaluate the importance for waterbirds of a lagoon around the freshwater lake, we conducted 26 censuses over 1 year on seven blocks with different landscape elements in a small lagoon. A total of 25 species were found and most of them (72%) belonged to a guild in which birds forage without diving. Species density (per ha) and diversity was high in blocks where Zizania latifolia Turcz and Phragmites australis L. reed beds existed. Not all of the waterbird species were feeding all the time, but were often resting in their preferred blocks, suggesting that they use the lagoon as both a refuge and a feeding site. Habitats with a structural reed bed community and shallow waters (<1 m depth) may be crucial determinants of high waterbird diversity in this small lagoon around which many people live. [ABSTRACT FROM AUTHOR]