Charismatic mammals remain a linchpin in attracting publicity and funds for the conservation of native habitats and organisms. Unfortunately, the same animals are frequently scarce and difficult to survey. For many, confirming their presence through faecal surveys is the only cost-effective approach. Here we show that, contrary to received opinion, expert naturalists fail reliably to distinguish pine marten Martes martes faeces (‘scats’) from those of foxes Vulpes vulpes. Moreover, their judgement fails completely when the animals and their scats are at their most scarce. This unexpected result from such a well-studied species has important implications for the monitoring of endangered mammals. We recommend that in the future, a multi-evidence approach should be adopted to monitor elusive mammals, involving DNA methods, cast hair identification, camera traps, and non-leading ‘sighting’ questionaires. For national surveys, it may soon become cost-effective to screen large numbers of samples using microarray technology.

During a zoological survey in north-west Madagascar (Sahamalaza Peninsula) we documented aspects of the natural history of Boophis occidentalis (formerly a subspecies of B. albilabris and here raised to species level). Individual age assessed by skeletochronology ranged from 4 to 11 years. Breeding behaviour was observed at a seasonal stream after heavy rainfalls: five choruses of eight to 90 males aggregated in shallow brook sections. The males emitted low frequency calls and engaged in scramble battles. Only two females were found. A couple laid a large number of eggs, attached as a single layer on submerged stones. Tadpoles reared from these eggs had the typical morphology of brook-breeding Boophis species with a 1:5+5/3 keratodont formula and a relatively flattened body. Adult males had an anteroventrally oriented cloaca, a morphological trait shared with B. albilabris. Advertisement calls were similar in general structure to those of B. albilabris recorded at Anjanaharibe-Sud. They were unharmonious and consisted of pulsed notes emitted at irregular intervals. Much lower pulse rates in B. albilabris (30–38 pulses/s) than in B. occidentalis (90–109 pulses/s) support the specific distinctness of these taxa. The combination of characters related to reproductive biology in B. occidentalis and B. albilabris is unique in Boophis. The acontinuous breeding behaviour and large number of eggs per clutch are traits found in the pond-breeding species of the B. tephraeomystax group, while larval morphology and habitat are characteristic of brook-breeding species. Available morphological and molecular data place B. albilabris and B. occidentalis into the brook-breeding Boophis radiation. The acontinuous timing of reproduction and large egg number may be secondary adaptations that allowed the species to colonize arid regions of western Madagascar.

Sexual size dimorphism in Tengmalm's owls Aegolius funereus outside the breeding season was investigated by trapping owls on migration during autumn. Owls were accurately sexed using PCR-based molecular techniques. Females were 4% heavier than males, but were c. 30% lighter than during the breeding season, when they carry large fat deposits and can be twice as heavy as males. Thus sexual mass dimorphism outside the breeding season was substantially lower than reported previously for the breeding season in this species. Females also had 2.5% longer wings and tail than males, but there was no difference in wing-loading, indicating that flight proficiency was similar between the sexes. Though the degree of sexual size dimorphism is small, large female size might be an adaptation for accumulating larger fat reserves, while smaller male size allows more efficient flight and hunting. This study highlights the importance of investigating sexual size dimorphism in owls outside the breeding season to avoid overestimation of female body mass.

The kodkod Oncifelis guigna has one of the smallest distributions of wild felids, being geographically restricted to a narrow strip within Chile and Argentina. An investigation of population demography and habitat selection was carried out using trapping and radio-telemetry techniques in transitional Valdivian forest at two sites in southern Chile. The mean home-range size was estimated at 269 ha with considerable overlap of ranges and core areas giving a density of combined adults and sub-adults of 0.97/km2. Forest, thicket-forest, and scrub-thicket predominated in the ranges of most individuals and habitats at less than 50 m elevation were more frequently used than higher slopes. With the exception of páramo and thicket, all other habitat types were used more frequently than expected by at least one of the kodkods. The study confirmed the strong habitat association with Valdivian and Araucaria forests previously reported for this species, but also suggested a more flexible use of habitat within home ranges and individual preferences of habitat used as core areas. Flexibility in resource use and mutual avoidance may explain why kodkod ranges overlap and populations reach high densities locally. This high degree of adaptability may well be relevant to the long-term survival of this species in an ever increasing, anthropogenically-modified environment.

Crocidura tadae was first reported as a new species from Orchid Island by Tokuda & Kano (1936). However, both C. tadae and C. kurodai from Taiwan were considered as subspecies of C. horsfieldii by subsequent researchers. In the present study, the karyotypic and morphological differences among the potential C. tadae specimens from Taiwan main island and two offshore islands (Orchid Island and Green Island) were examined. The results revealed that there is no significant difference in the karyotypes of these shrews but that their karyotype is different from that of other Crocidura species. Therefore, the Tadae's shrew C. tadae Tokuda & Kano, 1936 should be a valid species. Furthermore, morphological variation in 25 external and cranial characters of 106 specimens were analysed using univariate statistics, and eight selected characters were used for multivariate analyses. Univariate statistical comparisons of the three insular samples revealed that shrews of the Green Island population were the largest in most measurements of characters and shrews of the Orchid Island population were the smallest. Multivariate analysis differentiated the Taiwan samples from the other two insular samples. Therefore, three subspecies of C. tadae are recognized: C. t. tadae (Orchid Island); C. t. kurodai (Taiwan) and C. t. lutaoensis subsp. nov (Green Island).

The Hoplias malabaricus primary spermatogonium shows a large nucleus, central nucleolus, and low electron-dense cytoplasm containing nuages. In cysts, they undergo several mitotic divisions with incomplete cytokinesis, giving rise to secondary spermatogonia. These are smaller than the primary spermatogonia and their nuclei have one or two eccentric nucleoli. Spermatocytes I can be identified by the presence of synaptonemal complexes. Spermatocytes II are smaller than spermatocytes I, displaying roughly compacted chromatin. All these cell types remain interconnected by thick-walled intercellular bridges, which have membranous reinforcements during mitosis and meiosis. These cell types show a well-developed endomembranous system, one of the centrioles anchored to the plasma membrane and small nuages. Their mitochondria are large and circular, with few cristae. In the last generations of spermatogonia, the mitochondria are smaller, elongate and have more cristae. In the spermatocytes, the mitochondria are small and round. Similarities found in relation to germ cells of other teleosts are discussed.

One hundred and sixty-four museum specimens of the tree agama Acanthocercus a. atricollis were measured and dissected to examine sexual size dimorphism, reproduction and diet. Foraging mode and behaviour were also quantified in a wild population to obtain a broader picture of their foraging ecology and to test the hypothesis that tree agamas are ambush foragers. Males and females did not differ significantly in snout–vent length (SVL) or tail length; however, mature males had larger heads than females of the same body size. The smallest female showing sexual maturity was 96 mm SVL and the smallest male was 82 mm SVL. Mean clutch size was 11.3 and was positively correlated with female body size. Reproduction was seasonal and male and female reproductive cycles were synchronous. Testicular volume was greatest during August–September and females contained enlarged follicles during August–December and showed no evidence of multiple clutching. Tree agamas fed on a broad spectrum of arthropods (10 orders), including millipedes, which other lizard taxa have been reported to avoid. Gut contents were dominated numerically by ants (92%), followed by beetles (4%). Volumetrically, orthopterans (26.8%) were most important, followed by beetles (26.3%) and ants (17.9%). Compared to adults, juvenile diet by volume was dominated by ants and consisted of fewer large prey items (e.g. beetles and orthopterans). Seasonal effects in both prey diversity and volume were evident. Tree agamas are classic ambush foragers. They spent only 4% of their time moving and made few movements per minute (mean = 0.4). When stationary, adult tree agamas positioned themselves on tree trunks (34.7%), on lateral branches (41.8%) and occasionally, on the ground (23.4%). No evidence of trophic partitioning (intraspecific niche divergence hypothesis) was found and field observations revealed that males defend territories and engage in combat. This supports the idea that selection may be favouring larger head size in males, as an outcome of male contest competition.

The general aim of the present study was to test whether there are differences in the occlusal design of the ruminant selenodont molar, and by examining correlations between tooth form and diet, improve our understanding of the function of the selenodont molar within the Bovidae. Twenty-six species of bovid ruminants were grouped into the three feeding types established by Hofmann (1968) – i.e. browsers, grazers and intermediate feeders. The characteristics of the shape, number, width and length of the enamel ridges were found to correlate with the hypothesized function of the molar occlusal surface. These follow the principles applied to non-bovid species where adaptation of the occlusal surface has been investigated in some detail. Thirteen characteristics of the occlusal surface were scored. ANOSIM results reject the null hypothesis that there are no differences in the selenodont molar occlusal surface. SIMPER results showed that all the characteristics scored contributed to the differences between groups, and crown height was not explaining the major dissimilarity between feeding groups. Differences in enamel ridge characteristics between feeding types suggest that food is being processed in essentially different ways by the browsers and grazers. Intermediate feeding species cluster within the other feeding types, depending on what the major component of the diet is. The grouping produced by the MDS, based on dental characters, closely agrees with Hofmann's classification based on gut structure.

Environmental variables shaped the morphology of tadpoles of the common frog, Rana temporaria, in various ways at the Pyrenean locality Circo de Piedrafita. Examining only specimens in similar developmental stages, those from small ponds (with higher temperature and higher tadpole density) had lower growth rates, lower relative tail height, lower relative body width and fewer labial keratodonts and keratodont rows. The variation in keratodonts may have been caused by heterochrony related to the slower growth rate. The number of lingual papillae also differed between ponds but was not related to pond size. Higher predator densities caused a higher percentage of damaged tails and a lower relative tail length in specimens with apparently intact tails, probably as a result of incomplete regeneration after mutilations earlier in development.

Cricetomys gambianus is an important source of protein for human consumption in many parts of sub-Saharan Africa. Wild populations are under considerable hunting pressure, suggesting that captive rearing may be desirable. Successful captive-breeding programmes require a better understanding of reproductive physiology and behaviour. Eight groups containing a total of 68 C. gambianus females were used to characterize the reproductive pattern, including the occurrence and duration of oestrus, the cycle length, the oestrous cyclicity and the mode of ovulation. These female groups were kept in different social and physical environments and examination of vaginal smears were carried out at different periods. Results of the vaginal cytology examination showed two characteristic stages of the cycle: ‘oestrus’ and ‘anoestrus’. Oestrus appeared on average 1.3 times only in one female during 1 month, but its occurrence varied between 0.4 and two times in a month. The mean oestrous length was 3.3 days and ranged from 1.4 to 7.8 days. The average cycle length was 7.9 days but varied between 3 and 15 days. These results showed an irregular cycle pattern and revealed that C. gambianus may be an induced ovulator. Housing events, such as the presence or the absence of a male and the type of cages or rearing room, and the dry and the rainy seasons did not seem to influence the cycle pattern in this species. Further investigations on the basic reproductive biology of Cricetomys are necessary to provide the basis for developing farming methods that will yield high productivity.

Using museum specimens collected in Israel during the second half of the 20th century, no support was found for the hypothesis that body mass and tarsus length of chukar partridges Alectoris chukar has changed as a result of global warming. Body mass showed fluctuations during the year, reaching a maximum in late winter and spring and a minimum in summer. Bergmann's rule predicts that in warm-blooded animals, races from warm regions will be smaller than races from colder regions, and a wider explanation states that body size is positively related to latitude. Because of its topography and varied climate, Israel provides a unique opportunity to separate partly the effect of latitude from that of ambient temperature, thus testing if Bergmann's rule is related to latitude or to climatic variables. We found that body mass (and marginally also tarsus length) declined significantly with decreasing latitude in accordance with the wider explanation of Bergmann's rule, but ambient temperature explained a much smaller fraction of the variation in body mass than latitude. These results weaken the traditional explanation to Bergmann's rule that a heat conservation mechanism causes the latitudinal size variation.

The echolocation calls of insectivorous bats of the northern Yucatan Peninsula, Mexico, with the exception of the phyllostomids and molossids, are presented. The aim is to provide a catalogue of bat sounds that can be used for acoustic inventories of insectivorous bats using the Pettersson heterodyne and time-expansion bat detectors. The acoustic method can be used alone or in combination with inventories based on mist-netting, a method more suitable for the low-intensity echolocators (mainly the phyllostomids), which are difficult to monitor acoustically. The insectivorous species of the Yucatan are generally easy to identify by their echolocation calls, particularly when combined with visual observations of foraging bats at dusk.

In temperate ungulates, the body weight of juveniles at the onset of winter is a crucial determinant of survival and can also influence subsequent reproductive success. However, growth may be retarded post-weaning, during winter, as a result of resource restriction and/or the demands of thermoregulation in harsh climatic conditions. Post-weaning growth rates of juveniles were compared in relation to varying density in two populations of roe deer Capreolus capreolus (Chizé, Dourdan) monitored for 10 and 15 years, respectively. Body growth of fawns continued over the post-weaning stage of the juvenile period (October–March) at the rate of 0.017 kg/day at Chizé and 0.014 kg/day at Dourdan. Deer density had no influence on this post-weaning growth rate of juveniles in their first winter. However, deer born in years of high density weighed less at a given date than those born in years of low density because of their smaller body size at the onset of winter, indicating density-dependent rates of growth before weaning. At Chizé, the sexes grew at the same rate, but sexual dimorphism was apparent as males weighed about 1 kg (8%) more than females at a given date. At Dourdan, no significant sexual dimorphism was detected, although females tended to be heavier than males at a given date. We conclude that density influences juvenile body weight (through its effect on birth weight and/or post-natal growth rate) before weaning in this species and, despite continued growth after weaning, during winter, roe deer whose early growth is limited through interspecific competition cannot compensate for this early restriction.

For Gryllus bimaculatus (Orthoptera: Gryllidae), a comparison was made of the prediction from species recognition theory that stabilizing selection acts on mate recognition traits and that of sexual selection that predicts diversifying selection on mate recognition traits. The calling songs and morphometrics of four populations of field crickets from South Africa were compared. Song characteristics generally showed less between-population variation than did morphometric variation. This applied in particular to the song characteristics known to be important in species recognition. Within-population variation of species recognition traits were significantly smaller than for other call traits as well as morphometric traits. This is consistent with the expectation that stabilizing selection occurs for species recognition traits within populations as well as throughout their geographical ranges. No song traits correlated significantly with body size. Our study suggests that the calling song traits involved in mate recognition lack the variation required for sexual selection to operate. However, the amount of variation inherent in some of the other song parameters of field crickets still has the potential to give rise to sexual selection based on traits other than body size.

North Atlantic harbour porpoises Phocoena phocoena (L.) face considerable energetic challenges, as they are relatively small marine mammals with an intense reproductive schedule and a cold-water habitat. Post-natal growth of these porpoises was described using ontogenetic allometry and body composition techniques. The cross-sectional sample contained robust calves, immature, and mature porpoises (n = 122) incidentally killed in commercial fishing operations between 1992 and 1998. Total mass and the mass of 26 body components were measured using a standard dissection protocol. Most body components grew similarly in female and male porpoises. Blubber, brain and skull were negatively allometric, while muscle and reproductive tissues exhibited positive allometry. Female heart, liver, intestine and mesenteric lymph node grew at significantly higher rates than in males. Male locomotor muscle and pelvic bones grew significantly faster than in females. High growth rates for visceral and reproductive organs in porpoises, relative to other mammals, may underlie their early maturation and support their intensive, annual reproductive schedule. Relative to other cetaceans, porpoises seem to allocate a larger percentage of their total body mass to blubber. This allocation to blubber, which is greatest in calves (37% of body mass), may provide harbour porpoises with the thermal insulation required to live in cold water. The factors influencing growth rates and differential investments in body composition seem to change at various stages of a porpoise's life. Energy allocation in porpoises seems to shift from an emphasis on developing an insulative blubber layer in young animals to preparing the body for annual reproduction at sexual maturity.

The relationships between radio-collaring/tracking and 12 biometric parameters in a population of badgers (Meles meles) that were live-trapped in south-west England were investigated. The length of time for which a badger had worn a radio-collar was selected as an explanatory variable in generalized linear models of three biometric parameters (body condition, body weight and testes volume) irrespective of whether or not age class was included as a variable in the analyses. There was evidence that badgers that had been carrying a radio-collar for 1–100 days had lower body condition scores both when compared to badgers that had not been collared and with those that had been collared for longer than 100 days, suggesting a post-collaring acclimation period. In addition, the time period between first and last capture was longer for radio-collared than non-collared badgers. It is unlikely that this was due to an effect of collaring on trappability or to non-random selection of badgers for collaring. Although testes size differed between non-collared badgers and badgers that had been tagged for > 100 days, the relationship between radio-collaring and reproductive output remained unproven. These results highlight not only the need to assess the welfare aspects of radio-collaring but also the potential intricacy of corollaries of collaring. Explorations such as that reported here are important to the validity of studies that make use of radio-telemetry.

The remarkable diversity in chromosome number within Planipapillus Reid 1996, the most speciose genus of peripatopsid onychophorans, centred in the alpine region of south-eastern Australia is documented. Robertsonian, whole-arm rearrangements account for the twofold range of diploid numbers in Planipapillus. Ooperipatellus Ruhberg 1985, another clade of oviparous onychophorans, shows a very different pattern, with no karyotypic diversity among species from Australia and New Zealand. Rate constancy in chromosomal evolution among peripatopsid genera would indicate an ancient radiation in Planipapillus, with extant species representing relictual survivors of more recent Pleistocene climatic upheavals. Conversely, if the rearrangements in Planipapillus are the result of recent and rapid karyotypic restructuring, the karyotypic and species diversity within the genus may be attributed to recent population fragmentation and isolation resulting from the repeated glaciation and warming cycles of the Pleistocene rather than stemming from a more ancient radiation. Data from other animal groups support a model of accelerated rates of Robertsonian centric fusions concordant with a recent radiation in Planipapillus. Karyotype change may be an important factor in the generation and maintenance of Planipapillus diversity.

The Malay civet Viverra tangalunga is a relatively little known member of Borneo's carnivore community found throughout Peninsular Malaysia, Palawan, Sumatra and adjacent islands and Sulawesi. To investigate the basic ecology of this species and examine the potential impact of selective logging, a radiotelemetry study was carried out in the Ulu Segama Forest Reserve in Sabah, East Malaysia. From December 1995 to June 1997, home range, movement and activity data were collected on 12 study animals in a dipterocarp rain forest, and comparisons made between civets in a selectively logged and an unlogged site. Mean home-range size was 110 ha and did not differ between sites or gender. In areas of range overlap, radio-collared civets tended to avoid one another. Day beds were located on the ground and were associated with dense cover. Activity levels averaged 55% and were similar between forest types and gender. Most activity occurred from 18:00 to 07:00 during which mean activity was 81%. In a single day, males travelled further and covered a larger part of their home range than females. Roads and trails were used by both sexes, and roads were the only observed source of mortality resulting from vehicles. While density was higher in the unlogged forest, this species persists in both areas. The ability to survive in disturbed habitats might be influenced by the proximity of undisturbed habitat that served as a biological reservoir, or source of individuals to immigrate into the disturbed habitat.

Breeding of the threatened long-tailed bat Chalinolobus tuberculatus was studied over seven summers, 1993–2000, in temperate rainforest, Fiordland, New Zealand. Reproductive history of 789 marked bats from three social groups was investigated. Seventy per cent of births occurred over a 10-day period in mid-December. Young began flying at 5–6 weeks and nipples of reproductive females were regressing 2 weeks later. Sex ratio at birth was equal. Lactation coincided with highest annual air temperatures and peak abundance of flying invertebrates. Date of first birth varied by 4 days annually, but date of first flight varied by 17 days. Males had distended cauda epididymides at 1 year old (mean±SE = 1.63±0.16 years) and epididymal distension peaked in early autumn. Females first gave birth at 2–3 years of age (2.33±0.08 years). The short, highly synchronous breeding season, birth of single young, early mating in autumn, and late age of female sexual maturity compared to similar-sized vespertilionids, may be related to low food availability and unpredictable cold-temperate weather conditions. Annual productivity did not differ among groups but probability of survival of juveniles varied from 0.26 to 0.88 and was inversely proportional to size of natal group. Variability in breeding parameters was unrelated to climate or body condition of bats. The group with highest survival rates contained reproductive females and juveniles with significantly higher body condition. Differences in roost site or food quality within the home range of each group, varying genetic quality of members of the groups, or density-dependent mechanisms, may explain differential survival, but these hypotheses require investigation. A population crash and poor productivity in 1996 coincided with an irruption in the numbers of stoats Mustela erminea implying that predation by introduced animals can cause periodic population crashes. These results should be used to examine implications of these hypotheses on the long-term viability of Chalinolobus populations.

Sperm-dependent parthenogens are expected to promote higher female fecundity at the expense of the production of excessive numbers of sperm. They are also expected to trade sperm strictly, in order to compensate for the loss of nutrients invested in sperm, that otherwise could be allocated to the female function. In this paper, we present evidence that in a natural population of the freshwater planarian Girardia (= Dugesia) tigrina, sperm-dependent parthenogenesis is alternated with fissipary, a combination not reported before for freshwater flatworms. More specifically, we found that most individuals that engage in a copulation have no or only few testes and sperm available, despite the presence of a fully developed penis, indicating that male allocation is fairly low in this (dense) population. Female fecundity on the contrary is rather high, with isolated individuals producing up to six fertilized cocoons over a 3-week period, releasing five young per cocoon on average. An analysis of the mating behaviour further shows that matings in this species are simple and direct with no distinct courtship behaviour. Copulations last for about 36 min and occur at a rate of at least one copulation a day. Bilateral sperm transfer is the rule, but a considerable number of copulations are unidirectional or without sperm transfer. Non-reciprocal inseminations mainly result from the fact that one or both partners has no sperm stored prior to copulation, indicating that strict sperm trading plays no role in this population of G. tigrina.