Teruo Doi

Comparative analyses on food habits of Japanese marten, Siberian weasel and leopard cat in the Tsushima islands, Japan

Food habits of three sympatric carnivore mammals in the Tsushima islands of Japan were studied during 1986–91. Scats of the Tsushima marten (n=1236), the Siberian weasel (n=218) and the Tsushima leopard cat (n=350) were collected monthly and the food items were determined by scat contents analysis. Marten was omnivorous showing a high level of diversity of food throughout the year. The important foods for marten were fruits and berries from spring to autumn, insects in summer and autumn and small mammals all year round. Leopard cat preferred to hunt wood/mice and birds, and remained a flesh meat specialist throughout the year. Weasel was intermediate between marten and leopard cat, but was slightly biased towards the flesh meat eater. The three carnivores do not compete against one another for food, except for small rodents. A conflict for food between leopard cat and weasel was suggested to be more intense than that of other combinations based on diet overlapping. Marten may be characterized as an opportunistic generalist. When interspecific competitors existed, or human disturbance to the habitat occurred, the preferential flexibility of the marten to alternative food resources might become more advantageous than the other two species.

Mitochondrial DNA Variations in Local Populations of the Japanese Sika Deer, Cervus nippon

A partial sequence of the mitochondrial cytochrome- b gene was determined for seven subspecies of sika deer ( Cervus nippon ) in the Japanese Islands. Nine mitochondrial DNA genotypes were distinguishable among deer sampled. Sequence analysis revealed two major phylogenetic groups comprised of northern (Hokkaido-Honshu) and southern (Kyushu) local populations. Estimated nucleotide divergence between genotypes found in southern populations was ≤1.1%, which indicated that genetic differentiation within this group occurred recently. Phylogenetic data suggest that the biogeographical boundary between northern and southern populations of sika deer lies somewhere in the Honshu mainland and not in channels that separate each Japanese Island as has been suggested. C. n. keramae , an endangered subspecies in the Kerama Islands, was found to be genotypically close to other subspecies from southern populations. C. n. keramae may have descended from deer originally introduced from Kyushu Island.

Mating behaviors, courtship rank and mating success of male feral cat (Felis catus)

The mating behavior of the male feral cat (Felis catus) living on a small island was investigated. The cats in the study area (6.0 ha) formed the “feeding groups” at the garbage sites (Yamane et al. 1994; Izawa et al. 1982). We examined the factors influencing fighting ability, rank during courtship, and mating success of the male cat. Males with heavier body weight mostly won over lighter males in the agonistic encounters during the estrous season. Heavier males occupied the more advantageous positions to copulate with the estrous females and had higher mating success. These results suggest that body weight was one of the important factors affecting the courtship rank and the mating success of the male cat. When males visited and courted the females of feeding groups other than their own, they were sometimes defeated by the lighter males in that particular group, which lowered their courtship rank and success in copulations. These results indicate that the location of the courting male (inside or outside of its own group) and the kind of females they courted (member of the same group or not) were also important factors.

Movements and use of home range in the Iriomote cat (Prionailurus bengalensis iriomotensis)

Movement pattern of the Iriomote cat Prionailurus bengalensis iriomotensis was studied on Iriomote Island, Japan by radio-tracking. The influence of sex and reproductive status of cats on their daily movement distance (DMD), straight-line distance (SLD), daily movement range (DMR) and other relative indices of movements was estimated. DMD was longest in males (3.2 km) and shortest in females without kittens (1.9 km). Also, males moved faster than either females with or without kittens (0.34, 0.25 and 0.25 km/h, respectively). During the mating season, males moved faster and their DMRs were larger than during the rest of the year. The SLD/DMD ratio in males was similarly high in both seasons (0.29 and 0.33), which indicates that their daily routes were expanded over large areas year-round, possibly to maintain a continuous control over their home range. In contrast, SLD/DMD varied seasonally in breeding females. It was low (0.09) during the lactating period, when females returned repeatedly to the den with kittens and it became high (0.32) out of the breeding season. Breeding females moved equally long DMDs in both seasons, whereas non-breeding ones moved shorter distances during the breeding period. These differences may be related to seasonal changes of food abundance. Cats moved intensively, as indicated by long (812–1139 m) routes per km2 of their home range, and occasionally visited distant parts of their ranges in a short time (4–5 days). On the other hand, they showed a relatively slow increase of the patrolled area, from 10% to 36% of their home ranges, in the first and fifth day, respectively. Movement pattern of Iriomote cats showed no clear relation to active defence of home ranges.

The reproductive tactics and activity patterns of solitary carnivores: the Iriomote cat

Felids are generally considered to be crepuscular and nocturnal in their activity, but few studies have attempted to analyze the variability of their activity patterns. We studied the daily activity of the Iriomote cat Prionailurus iriomotensis by radio-tracking on Iriomote Island, Japan. The general activity patterns of Iriomote cats showed slightly prevailing activity during dark periods of the day with particular peaks at dawn and dusk or during the early hours of the night. However, these patterns were clearly dependent on the sex and reproductive status of the cat. Peaks of cats’ activity coincided with those of their main prey. On average, the cats were active for thirteen hours per day. During the mating season, the rhythm of activity in males followed that of breeding females, but not that of non-breeding ones. Males exhibited 11% higher total daily activity and longer active bouts during the mating period than in the remainder of the year. Breeding females had additional mid-day activity peak during the nursing period, but their total time of activity per day was 16% lower than in the period of kittens’ independence. Their active bouts were shorter and more frequent during nursing than at other times. These results suggest that lactating females perform frequent movements to and from the den site to care for kittens. During the non-nursing period, females increased their activity, possibly in response to lowered prey abundance and the need of intensive foraging to recover after lactation. Seasonal and sexual variation of activity patterns in the Iriomote cats confirmed the existence of different reproductive strategies of males and females of these solitary carnivores.

Local distribution of two species ofApodemus in Kyushu

Local distributions of two species ofApodemus, A. argenteus andA. speciosus, were studied by the correct estimation of peak density of mice and the detailed description of the habitat. Multiple regression analysis is applied to these distributional data setting with four variables as altitude, forest type, relative cover of shrub layer and age of forest. The local densities of both species and the percentage abundance ofA. argenteus can be completely predicted by use of the regression coefficients. The density ofA. speciosus correlates with the altitude of habitats, and that ofA. argenteus does with the age of forest. The mean relative cover of shrub layer influences the dominancy ofA. argenteus when both species occur sympatrically.

The effect of habitat on home range size in the Iriomote Cat Prionailurus bengalensis iriomotensis

ABSTRACT The seasonal variation in home range size of one male and one female Iriomote Cat Prionailurus bengalensis iriomotensis was studied by radio-tracking and automatic photography on Iriomote Island, Japan. The study was conducted in the Shirahama area located in the western part of the island. Shirahama provides a small area of suitable lowland habitat (<50 m a.s.l.) for the Iriomote Cat. Two individuals, one male and one female, were confirmed to be resident in this area. The periodical home range size of the male was 1.24 ± 0.41 km2 and that of the female was 1.30 ± 0.54 km2 throughout the year, with no significant difference between them. We compared the results of these observations with those from another area of suitable habitat in Funaura and discussed what factors may affect male home range size. The home range of the male cat in Shirahama was found to be only half the size of that of males in Funaura, though it showed similar seasonal fluctuation. The home ranges of females were similar in the two areas. Our results provide empirical confirmation of the influence of the number and distribution of females on male home range size in a solitary felid.

Post-copulative guarding: mating behavior of non-territorial male sika deer (Cervus nippon) in an enclosure

The mating behavior of captive male sika deer (Cervus nippon), which hold no territory or no harem, was studied on Nozaki Island, in October 1990. During the study period two females came into estrus and a dominant male monopolized the copulation with these females. We observed two characteristic behaviors, which had never been observed in harem-making or territorial males. First, the dominant male usually tolerated the presence of other males. However, he was seen to drive away other males, defending the one receptive female on her day of estrus. The frequency of aggressive interactions, e.g., aggressive approach and chasing, increased on the day of estrus (aggressive approach: U = 2, z = − 1.835, p = 0.06; chasing: U = 0, z = − 2.820, p < 0.01). Second, the dominant male remained within a radius of 5 m of the served female following copulation for more than 10 h, and chased away any males approaching the female. This behavior, therefore, was considered post-copulative guarding. Multiple copulation by females was observed in the wild population on Nozaki Island. High tolerance to subordinate males and post-copulative guarding of females are mating tactics of the dominant male associated with captivity.

Helminths of the Tsushima leopard cat (Felis bengalensis euptilura).

Three Tsushima leopard cats (Felis bengalensis euptilura) in Japan were collected as road kills. Three species of trematodes (Pharyngostomum cordatum, Paragonimus sp. and Dicrocoeliidae gn. sp.), one species of cestode (Spirometra erinacei) and nine species of nematodes (Arthrostoma hunanensis, Uncinaria felidis, Uncinaria sp., Ancylostoma tubaeforme, Molineus springsmithi, Toxocara cati, Capillaria aerophila, Capillaria feliscati, and Capillaria sp.) were found. Among these helminths, Arthrostoma hunanensis, Uncinaria spp., and Molineus springsmithi have not been reported previously in Japanese domestic cats.

Pollination partners of Mucuna macrocarpa (Fabaceae) at the northern limit of its range

Mucuna macrocarpa is a plant found in tropical and subtropical regions that requires an “explosive opening.” Explosive opening is the process that exposes the stamen and pistil from the opening of the carina. This process is needed for cross pollination; however, the plant cannot open itself and opening by an animal is needed. The most common opener of Mucuna flowers is several nectar-eating bats (e.g., Syconycteris), but the flying fox, Pteropus dasymallus, is the only opener of M. macrocarpa on the subtropical island of Okinawajima. Here, we present the explosive openers and possible pollinators in the northernmost and temperate Kamae region, Kyushu, Japan, where nectar-eating bats are absent. The Japanese macaque, Macaca fuscata, and the Japanese marten, Martes melampus, were the explosive openers observed during our survey in Kamae. Martens opened flowers using their snout in a manner similar to that of the flying fox, whereas macaques opened flowers using their hands. This is the first time that an animal has been observed opening these flowers with its hands rather than snout. In total, 97% (n = 283) of explosively opened flowers were opened by macaques, and the macaque largely contributed to the overall flower opening. Because many pollen grains become attached to the explosive openers, they are considered to be primary pollinators. Furthermore, two bee species, Apis cerana japonica and Bombus ardens ardens, also visited opened flowers and collected pollen, and they were possibly secondary pollinators.