Introduction of the bullfrog Rana catesbeiana is considered detrimental to native fauna. However, methods for controlling bullfrog populations have not yet been established. Managing habitats to resist invasion is important for alien species that are difficult to control directly. We surveyed habitat characteristics of paddy fields in eastern Japan inhabited by bullfrogs and analyzed their microhabitat selection. Our results suggest that adult bullfrogs prefer microhabitat with deep water. Therefore, it may be possible to prevent invasion of adults by keeping water shallow. Managing local habitats to prevent immigration may reduce the spread of bullfrogs on larger spatial scales.

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The growths in nature of male and female individually recognized salamanders Salamandra infraimmaculata were recorded for 21 years and 19 years, respectively. In most salamanders, increases in mass and length took place during the first 9–10 years of life. The increase in mass with age was more pronounced than that in either total body length (TL) or snout-vent length (SVL). TL proved to be sometimes unreliable as a measure to assess growth, because the tail tip was occasionally shriveled off by gangrene infection that sets in following young jackals’ bites. Also, SVL might not be accurately measured because of the natural distortion and bending of the spine in older salamanders, and mass was highly variable due to fluctuation in amount of prey consumed and, in females, to varying state of parturition: a litter weighed up to 30 g (corresponding to 100 neonates: 0.2–0.3 g each) and, moreover, a female did not always release her entire litter at once. As such, it is advisable to examine all of the three dimensions with hope that at least one of them may give a reliable measure for estimation of the growth in this species.

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We describe a new species of Calamaria Boie on the basis of a single specimen collected in broadleaved evergreen forest from Gia Lai Province, Central Vietnam. This is a large species (total length of the unique male 457 mm) characterized by rostral wider than high, with portion visible from above more than half of prefrontal suture; paraparietal surrounded by five shields and scales; presence of preocular; four supralabials, of which second and third entering orbit; modified maxillary teeth; five infralabials, of which first three are in contact with anterior chin shield; mental touching anterior chin shields; 3+191 ventrals, single anal scale; 23 divided subcaudal scales; tail relatively short, as thick as body, not tapering, with rounded end (8.1% of the total length); dorsum light greyish brown, with an indistinct dark neck collar and few dark blotches along posterior vertebral region; two pairs of light blotches on tail; venter yellowish beige, with dark outermost corners in each of ventrals and anterior subcaudals. A key to the Vietnamese and Chinese species of Calamaria is provided. Calamaria gialaiensis sp. nov. is the sixth species of Calamaria recorded from Vietnam.

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Mitochondrial DNA (mtDNA) was characterized for restriction fragment length polymorphism (RFLP) to evaluate the genetic variability of continental and island populations of Bothrops jararaca and the closely related B. alcatraz. Resultant data showed a geographic orientation in the genetic differentiation in B. jararaca and high haplotype similarity of B. alcatraz with the northern and middle latitude assemblage of B. jararaca. In the dendrogram illustrating haplotype divergences, two major clusters, conforming to geographical provenance of the snakes, were recognized. One cluster contained B. jararaca from the northern and intermediary areas and B. alcatraz, while the other cluster was composed only of B. jararaca sampled in temperate regions. MtDNAs of island populations of B. jararaca were very similar to each other as well as to those of the adjacent continental populations This indicates that the isolation periods of these islands were not long enough for their populations to accumulate differential substitutions in the mtDNA fragments.

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Sleeping site selection of Brookesia decaryi was investigated in a dry forest of northwestern Madagascar from mid-October 2004 to the beginning of May 2005. Sleeping site characteristics were recorded for 304 individuals. This chameleon species is diurnal, dwelling on the ground in the daytime, but at night all individuals were found perching on small plants, shrubs, dead fallen branches, or liana. Eighty percent of adult males, 73% of adult females, 85% of juveniles, and 82% of hatchlings slept on small plants. Approximately 70% of individuals chose a sprig or branch as a support during the sleeping time; the others selected a leaf or trunk. The preferred sleeping orientation was horizontal or oblique with head up. No tendency to sleep at the tip of support was observed. There were no sexual differences in sleeping site selection (perch diameter, perch height, and vegetation height), but there were significant differences in these variables among age classes. Body size was significantly positively correlated with perch diameter and perch height, but not with vegetation height. The primary factor that determines the sleeping site and position of B. decaryi may be predation avoidance, but other factors, such as morphological constraint and climate condition, cannot be excluded.

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A mark-recapture study was conducted for turtles of the Kizu River, Kyoto Prefecture, Japan, from 1999 to 2002. We captured 179 individuals and recorded 745 recaptures, involving four species (Chinemys reevesii, Mauremys japonica, Trachemys scripta elegans, and Pelodiscus sinensis) and the hybrid between C. reevesii and M. japonica. Of these, C. reevesii occupied 63% of the whole sample in individual number. In all four microhabitats (main stream, branch, pools, and irrigation canal), this species was most dominant. In both C. reevesii and M. japonica, females were significantly larger than males in carapace length and body mass. Analysis of age structure suggested that females live longer than males in these two species, as well as in T. scripta elegans. The movement distance estimated from recaptured turtles did not differ between sexes in any species with the maximum distance being 675 m, 375 m, and 734 m in C. reevesii, M. japonica, and T. scripta elegans, respectively. Species composition of the turtle community in the present study site distinctly differed from that in a nearby (<2 km) lentic habitat, where M. japonica was reported to be dominant. Such difference in species composition may reflect the difference in habitat preference between C. reevesii and M. japonica.

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Calotes versicolor, hitherto known from the Asian mainland, from eastern Iran, across the Indian Subcontinent, to Indo-China and Indo-Malaya, with several naturalized populations in both the New and Old Worlds, is here reported for the first time from Borneo (from Brunei Darussalam, in the northwestern part of the island). The ecological consequences of invasion of this agamid lizard, reported from studies elsewhere, include competition with other saurian species, and predation on local invertebrates and small vertebrates, with undesirable effects in terms of conservation of the local biota.

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