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The Kuril harbour seal Phoca vitulina stejnegeri is an endangered species which in - habits southeastern Hokkaido, Japan. Its population declined precipitously from between 1500 and 4800 individuals in the 1940s to a few hundred individuals in the early 1970s. The causes of this decline are thought to be commercial harvesting, bycatch in autumn set-net salmon fishing, and other human activities, including coastal fisheries. To quantify Kuril seal population trends, counts were performed each year at haul-out sites during the pupping season from 1974 to 2010 and during the moulting season from 1983 to 2010. The average population growth rate was ~4% per annum over the past 37 yr. Two haul-out sites (Kenbokki Island and Hattaushi) from which the species had disappeared in the early 1980s showed no evidence of being recolonized. Commercial harvesting ended in the late 1980s and probably had an effect on population trends until the 1990s. The bycatch of seals during autumn set-net salmon fishing in the 2000s remained similar to, or slightly greater than, that during the 1980s. Recently, seals have been observed at 9 haul-out sites during the pupping/moulting season along the coast of southeastern Hokkaido. Approxi- mately 70% of the seals found were at Cape Erimo (~500 seals) and at Daikoku Island and Akkeshi (~250 seals).

We investigated the distribution of brown bears (Ursus arctos) with white pelage in Kunashiri and Etorofu Islands, Southern Kuril Islands; we here name this white pelage form the Ininkari bear. The fur color of the brown bear varies considerably throughout its range, and many pelage variations have been reported. Ininkari bears are unique in having white fur only on the upper half of the body. There are no reports of bears with the Ininkari-type markings in other regions of the world. According to literature and interview surveys, Ininkari bears have been recognized since at least the late 1800s on Kunashiri and Etorofu. We surmise the reasons that distribution of Ininkari bears is restricted to these islands are the lack of predators and the low hunting pressure on brown bears there; these factors may allow the bears to maintain such a unique pelage.

Studies on the population dynamics of sea turtles require histological evaluation of the ontogenetic development and the activity of the gonads for reproduction. To investigate the growth-related changes of gonads in the immature male green turtle (Chelonia mydas), the histological changes of testes and epididymides and the localization of the androgen receptor, estrogen receptor a, estrogen receptor b, and progesterone receptor were examined. The testes were categorized histologically into six developmental stages, and a scarce relationship between straight carapace length and gonadal development was confirmed based on the histological analysis. Several kinds of steroid hormone receptors were examined to show distributions in both testes and epididymides, for which their immunoreactivities were enhanced according to the developmental stage of the testes. These results suggest that straight carapace length is not an adequate indicator of maturity determination, whereas histological and immunohistochemical evaluations are useful in identifying the growth stages of green turtles, owing to the higher sensitivity to steroid hormones that appear during growth. J. Exp. Zool. 309A:166-174, 2008. r 2008 Wiley-Liss, Inc.

ASTER aboard NASA’s satellite Terra is a high-resolution multispectral radiometer of 14 bands. The spatial resolution is 15 m in VNIR, 30 m in SWIR and 90 m in TIR spectra, respectively. With the data observed with ASTER, the land cover classification is produced for the Tarim Diversifolious Poplar Protection Area along the Tarim River in the northern Tarim Basin (Taklamakan Desert) in XinJiang, China. The classification of the vegetation (plants) in the arid and semiarid regions using remote-sensing technology is very difficult. Because the cause has low vegetable cover density and the influence of reflection from background soil is large. ASTER data are effective in studying the spectrum characteristics of land cover in arid and semiarid regions. The sensor has several bands in the shortwave infrared wavelength region that is designed for exploration of earth resources and study of the arid and semiarid region natural environment. However, we are not clear combination of which band is the most effective in research of the arid region like the Taklamakan desert in the data of 14 bands of ASTER. The optimum index factor (OIF), based on total variance within bands and correlation coefficient between bands, is a statistical approach to rank all possible three-band combinations. In the process of analyzing the data, the pixel sizes of all the data are converted (layer stacking and re-sampling) into consistent same size of 15 m. The three-band composite with the largest OIF value will have most information (as measured by variance) with the least amount of duplication (as measured by correlation). We used the OIF technique to rank all three-band combinations of ASTER original 14-band data over Tarim River Poplar Protection Area. Our study indicates that RGB color overlay using atmospheric corrected ASTER original bands 2, 3 (VNIR), and 6 (SWIR) has the highest OIF. When NDVI is considered as one ASTER band, highest OIF will have by carrying out bands 3 (VNIR), 4 (SWIR), and NDVI. In this study, we used highest OIF (bands 3, 4, and NDVI) succeeded in extraction of Tarim River Poplar Forest.

We assessed the original and recent distribution of sea otters (Enhydra lutris) along the coast of Hokkaido, Japan, based on information of remains from archeological sites, old hunting records, and records of recent sightings obtained from interviews. Some remains, including pups from one archeological site, suggested the possibility that some small aggregations had historically been distributed around Hokkaido. However, sea otters seem to have disappeared prior to commercial hunting in the 18th and 19th centuries, as no records could be found documenting the hunting of otters around Hokkaido during that period. Since 1973, intermittent sightings of otters have been made around Hokkaido, and since 1996, the sighting frequency has increased. Between 1962 and 2001, 119 sightings and six dead otters were recorded around Hokkaido. The source population of these otters is probably in the Habomai Islands of the southern Kurils. However, due to increasing anthropogenic habitat disturbance, it is unlike...

Several reports have been published on blood leptin concentrations in feral animals, including members of the Carnivora, using a commercially available multi-species radioimmunoassay (RIA) kit with anti-human leptin antibody. However, we observed weak immunoreactivity between recombinant canine leptin and anti-human leptin antibody, suggesting a limitation in the applicability of the RIA kit for leptin assays in Carnivora species. We tested the applicability of RIA and sandwich enzyme-linked immunosorbent assay (ELISA) with anti-canine leptin antibody to assay blood leptin in the dog (Canis familiaris) and the raccoon (Procyon lotor). When RIA was used for recombinant canine leptin and dog sera, values were much lower than those determined by ELISA at higher concentrations (>10 ng/ml), while rather higher at lower concentrations (

The ovarian cycle and conception of sika deer were studied to reveal factors responsible for delayed conception. Concentration of progesterone in feces from 12 female Hokkaido sika deer (Cervus nippon yesoensis Heude, 1884) was measured during the mating season in 2000. The cyclic pattern of fecal progesterone synchronized with estrous symptoms, which could hence be interpreted as indicating ovarian cycle. All observed females ovulated by 14 October. However, during the early mating season, females did not permit copulation at ovulation, and the length of luteal phase following ovulation without estrus was 9.8 ± 4.6 days (5–24 days). Most females conceived at the first copulation, which were confirmed by progesterone profiles that was sustained at a high level after the copulation. This indicates the presence of a functional corpus luteum, a state of pregnancy. Thus, some females had repeated ovulation without copulation several times, creating a 3–4 week variation in the timing of conception. But some females conceived very late in the mating season after the repetition of ovulation and copulation.

Periodic growth incremental lines are found universally in dental hard tissues. This periodicity theoretically allows for estimation of age, even in days, which would be useful in studies of wild animals. In the present study, enamel and dentin increments of the sika deer (Cervus nippon) were observed in ground sections with a polarized light microscope, and their periodicity was examined by the use of a chronological labeling method with fluorochromes. Enamel increments occurred at a mean interval of 10.6 (SD=1.5) microm, and mean spacing of dentin increments was 17.3 (SD=1.8) microm. Fluorochromic marking revealed that incremental lines form each day in enamel and almost every second day in dentin. The fluorescence-labeled lines suggest that enamel formation of the first molar is complete by the age of 5 months. Due to its longer interval of incremental lines and longer term of formation, we conclude that dentin is more suitable than enamel for day-age estimation in sika deer. Experimental confirmation of incremental growth periodicity in various species can improve the reliability of use of tooth increments for age estimation and life history reconstruction.

We investigated fetal development and the estimation of fetal age of 127 Hokkaido sika deer fetuses, categorizing them into three groups according to the nutritional condition of populations. The order and time of the appearance of ossification centers were clarified, and fetal age was determined based on bone length and the appearance of ossification centers. Then we observed the differences in fetal growth among three populations, and discussed the effect of poor nutrition on the fetal growth. The results suggest that fetal diaphysial length of the femur was affected very little by nutritional conditions, whereas conception dates were delayed and fetal weight was restricted as the nutritional condition became poorer. Although it is impossible to know the exact accurate fetal age in wild populations, it was possible to create a standard to estimate fetal age more precisely by the method described in this study. Both the bone length and the appearance of ossification centers are reliable indices to estimate fetal age precisely in measurements available from fetuses of unknown age, and can be applied to estimate the fetal age of other populations of sika deer, whereas estimation of fetal age based on weight is prone to great errors.

Variation in the parturition dates of captive sika deer (Cervus nippon) are explained by factors affecting conception date and gestation period. The timing of conception was related to lactational status, and all non-lactating females conceived before the median conception date. Young females were more likely to conceive after the median date of the conception than older females. Gestation period was not related to the fawn's sex or the female's age. No relationship between gestation period and female body weights was detected in 2000–2001, while an inverse relationship was observed in 1999–2000, a year with heavy snowfall. Conception dates explained most variations in parturition dates in 2000–2001, but gestation periods as well helped explain variations in 1999–2000. We propose that females in poor body condition compensate for poor fetal growth with an extended gestation period after a severe winter. Estimates of conception dates from fetal age or parturition dates should consider these complicating factors.

The phylogenetic relationships of Cervidae and Moschidae were examined using partial sequence data of mitochondrial DNA (mtDNA) cytochromeb. Ten new sequences were obtained for six species of Cervidae and Moschidae, and aligned with those previously reported for other deer species. Our results demonstrated that the phylogenetic status of the taxa inferred from molecular data was congruent with taxonomy based on morphological studies. Cervidae formed a monophyletic group that consists of four subfamilies: Cervinae, Muntiacinae, Hydropotinae, and Odocoileinae. Moschidae occurred at the base of the Cervidae clade. On the basis of molecular clocks for genetic distance, the divergence time of mtDNA haplotypes within the subfamily Cervinae, among subfamilies in Cervidae, and between Moschidae and Cervidae was estimated to date 2–7 MYA, 6–10 MYA and 8–13 MYA, respectively.

Population genetic structure of the spotted seal, Phoca largha, along coastal regions of Hokkaido was investigated, using mitochondrial DNA (mtDNA) sequences. A 571-bp fragment of the mtDNA control region and adjacent threonine and proline transfer RNA genes was sequenced from 66 seals. We categorized all individuals into three groups considering sampling area and season: twenty-four seals from the Sea of Okhotsk in winter, 11 seals from the Sea of Okhotsk coast in fall, and 31 seals from the Sea of Japan coast in winter. From the 66 animals, 57 haplotypes were identified. Compared with the harbor seal sequence, all spotted seals examined shared two deletions in the control region, which distinguished between the two species. Forty-nine haplotypes were represented by a single individual, and haplotypes shared by more than two animals were generally restricted to same sampling-groups. Phylogenetic trees did not indicate clear geographic differences among the three groups. An Analysis of molecular variances (AMOVA) did not showed any significant population genetic structure in Hokkaido spotted seals (Phi(st )= -0.003). Our results showed a high level of diversity but no genetic structure, and did not deny the possibility that seals in the Okhotsk breeding concentration mainly stayed in the fall Okhotsk and also inhabited in the winter Sea of Japan.

Reproduction of feral raccoons (Procyon lotor) in Hokkaido, Japan, was examined during a 2-year period by analysis of placental scars or fetuses in the uterus. Of 242 collected females, 69 (29%) were juveniles, 71 (29%) yearlings, and 102 (42%) adults. The pregnancy rate averaged 66% in yearlings and was significantly lower than the 96% average observed in adults (p

Skulls and canines of 460 sea otters from Lopatka Cape, Kamchatka, were examined to assess development patterns, individual variation and sexual differences. An allometric formula was applied to morphometrical data, and the relative growth of each character to total length of skull was analyzed. In both sexes, most morphometrical characters ceased growth at about 2 years of age. Canine root length increased rapidly during the first year of life, while crown length decreased due to remarkable wear. There was large individual variation in the feeding and breathing/sniffing apparatus, while there was little variation in braincase size. There were sexual differences in most characteristics, although males and females showed similar growth patterns. The coronoid process of the mandible showed positive allometry in both sexes, and we attributed this finding to feeding habits. The fact that only male mastoids showed positive allometry may be due to the need for male otters to maintain a passing territory.

Historical specimens of sea otters (Enhydra lutris) provide valuable information about the pre-bottleneck population. However, the sex of these specimens is often not known. We attempted to determine the sex of sea otters by means of polymerase chain reaction (PCR) amplification of the amelogenin and the zinc finger (ZFX/ZFY) regions. The PCR fragments of amelogenin amplified were same size regardless of the sex. On the other hand, we were able to distinguish the sex accurately by means of the sea otter-specific restriction enzyme (NlaIII) to digest a polymorphic site in the ZFX/ZFY region. This method was applicable to dental pulp from skull specimens with the use of novel inner primers (KH1/KH2). We suggest that with some modification, the ZFX/ZFY system can be applied to other species and to a variety of archaeological specimens.

To illustrate phylogeography of red deer (Cervus elaphus) populations of Xinjiang, we determined their mitochondrial DNA (mtDNA) control region sequences, and then investigated geographic variations and phylogenetic relationships between Xinjiang populations and other populations from Asia, Europe, and North America. The C. elaphus mtDNA control region shared different copy numbers of tandem repeats of 38 to 43-bp motifs which clearly distinguished the Western lineage from the Eastern lineage of this species in Eurasia. The western lineage comprised the Tarim populations from southern Xinjiang and the European populations, all of which had four copies of the motifs. By contrast, the Eastern lineage consisted of populations from northern Xinjiang (Tianshan and Altai Mountains), other Asian areas (Alashan, Gansu, Tibet, Mongolia, and northeastern China), and North America, all of which shared six copies of the motifs. MtDNA phylogenetic trees showed that there are two major clusters of haplotypes which referred to the Western and Eastern lineages, and that subgroupings of haplotypes in each cluster were congruent with their geographic distributions. The present study revealed that a boundary separating the Western lineage from the Eastern lineage occurs between Tarim Basin and Tianshan Mountains in Xinjiang. Meanwhile, North American populations were genetically closer to those of northern Xinjiang, northeastern China, and Mongolia, supporting that C. elaphus immigrated from northeastern Eurasia to North America through the glacier-induced land-bridge (Beringia) which had formed between the two continents after Late Pleistocene.

To study luteal function in the late gestational period of Phocidae (seals), we analyzed the localization of steroidogenic enzymes (P450scc, 3betaHSD and P450arom) and prolactin receptors in the corpora lutea of pregnant spotted seals (Larga seal; Phoca largha) immunohistochemically. P450scc, 3betaHSD and prolactin receptors were present in all luteal cells of each corpus luteum, and most luteal cells were immunostained for P450arom. Although we analyzed only two specimens, P450scc, 3betaHSD and prolactin receptors were negatively immunostained in the placentae. P450arom was present in the syncytiotrophoblast of placentae. These findings suggest that 1) the corpus luteum of the spotted seal synthesizes pregnenolone, progesterone and estrogen during late gestational period, 2) the placenta of this species do not possess the capacity to synthesize progesterone, and 3) like other terrestrial carnivores, this species requires prolactin to maintain the corpus luteum during pregnancy. These characteristics support the recent classification of family Phocidae in the order Carnivora, and suggest a relationship between prolactin and reproductive failure during the post-implantation period in pinnipeds.

Ten free-ranging female sika deer (Cervus nippon) were captured to obtain the reference values for acid-base status and blood gas when immobilized with the combination of medetomidine and ketamine. The mean +/- SE of PaCO2, PaO2, and HCO3- were 58.1 +/- 6.1 mmHg, 58.8 +/- 6.4 mmHg, and 36.0 +/- 4.4 mmol/l, respectively. Although acidosis and alkalosis occurred in three and two animals, respectively, no serious conditions were observed. The blood values, however, suggest that some degree of hypoxemia and respiratory acidosis with metabolic alkalosis are developed. The trapped deer showed a significantly higher than normal rectal temperature reflective of exertion.

Fecal progesterone assays were conducted in 3 captive female sun bears (Helarctos malayanus) segregated from males to characterize the species-specific reproductive pattern in their original distribution area in Sarawak, Malaysia. Peaks of fecal progesterone concentrations were observed once annually, and lactation was observed after increasing progesterone concentrations in all females without mating stimulus. These results suggest that sun bears in Sarawak, Malaysia, may have a seasonal reproductive pattern and ovulation was noted to occur spontaneously, followed by pseudopregnancy.

The distribution of the spotted seal, Phoca largha, along the coast of Hokkaido was investigated, based on personal interviews, surveys of haul-out sites, and records and direct examinations of seals. Interviews conducted in 1997 along the entire coastline of Hokkaido, confirmed that spotted seals have been observed in all eight regions of the island. Incidental harvests by fishing nets and damage control kills were confirmed in seven and in three regions, respectively. Examinations were made of live and dead specimens, and of specimen records from between 1971 and 1998 (n=605), all obtained from Hokkaido University, aquariums and zoos. Specimen and documentary records were most common in regions where incidental harvests and damage control kills were reported. Seasonal and regional variations in seal distributions were observed. Incidental harvests, damage control kills, and strandings were most common during salmon harvest season (fall), sea ice season, and the weaning period, respectively. Sub-adults and adults were found in areas with seasonal sea ice, while immature seals were recovered from areas with little or no sea ice. The fewest seal sightings and no haul-out sites were reported from southern Hokkaido, probably because warm sea currents discourage seals from using this area.

Measurements of shoulder height, body length, hind-foot length, and total body mass were collected from 309 Hokkaido sika deer (Cervus nippon yesoensis Heude, 1884) (115 males and 194 females) and analyzed statistically for sexual dimorphism and seasonal body mass fluctuations. The von Bertalanffy equation was fitted to the growth curves that resulted. Asymptotic shoulder height, body length, and hind-foot length were 106.2, 112.6, and 52.9 cm in males and 94.8, 103.9, and 49.4 cm in females, respectively. Total body mass showed distinct seasonal fluctuations, ranging between 102.8 and 151.0 kg in adult males and 68.0 and 99.8 kg in adult females. Male/female ratios in shoulder height, body length, hind-foot length, and total mass were 1.12, 1.08, 1.07, and 1.51, respectively. These results indicate that the Hokkaido sika deer is one of the largest subspecies, at least in skeleton size. A larger body and longer hind foot would seem to be evolutionary adaptations to Hokkaido's cold, snowy environment.

Since the musk deer distributed in the Dabie Mountains, Anhui was defined asMoschus moschiferus anhuiensis, its status has been disputed based on researches of morphology and ecology. This study further probed into its taxonomic status with principal components analysis (PCA) on skull measurements and mtDNA cytochrome b sequences (367 bp) analysis so as to clear its status. It is concluded that the figure and skull in Anhui musk deer are different from other species, and DNA divergence between it and other species is 6.24%–7.90%, which belongs to inter-specific difference. Thus, the study defines this musk deer as one distinct species,Moschus anhuiensis (Wang, Huet al.)

The authors determined gestational age from fetal weight, examined the range in conception dates, and classified the external fetal development process in sika deer of eastern Hokkaido. Gestational age (T) can be estimated from fetal weight (W) with the equation: T = (3 square root of W + 2.730)/0.091. Conception date can then be calculated back from date of kill of pregnant female, using gestational age. Though estimated conception dates ranged from 7 October to 17 January, most of them were concentrated between mid October and early November. In late November and after, nine conceptions were observed and six out of the nine late cases occurred in yearling females. This phenomenon is probably due to the excellent nutritional condition of deer in the study areas, which allows yearling females to mature sexually even in early winter. In fetuses, periods of tactile hair development, appearance of white spots, and development of general hairs overlap very little. In addition, these developmental changes occur at specific fetal weights. Based on these external phases, the gestation period can be divided into four stages. These stages will be useful for simple determination of fetal age in various sika deer populations.

Random amplified polymorphic DNA (RAPD) was exploited as a genetic marker to assess the level of genetic variation in populations of Sika deer, Cervus nippon, in Japan. DNA samples were collected from three local populations in Japan, namely, Kinkazan, Goyozan and Ashoro populations. Four arbitrary primers, when used individually, amplified an average of five RAPD fragments in the polymerase chain reaction (PCR). The number of polymorphic bands was scored to calculate band-sharing coefficients within populations. Average band-sharing coefficients revealed a higher degree of homogeneity in the Kinkazan population. Samples collected from larger populations, namely, Ashoro and Goyozan, revealed greater polymorphism than samples from the Kinkazan deer. Our data suggest that RAPD is useful as a marker for detecting genetic variations in populations of Sika deer with reduced levels of genetic diversity.

The authors studied some reproductive characteristics of wild female sika deer (Cervus nippon yesoensis Heude, 1884) in Ashoro District, Hokkaido. Large numbers of females attained sexual maturation at the age of yearling, and the pregnancy rate of yearlings and older was 96.4% (n = 28). These high levels of fertility should be considered the standard for high quality populations of sika deer. The estrus cycle began in late October. Twinning was exceptional. Sex ratio of fetuses was statistically 1:1, and there was no significant difference in fetal weights between males and females in March. The birth weight is estimated to be around 6 kg. Accessory corpora lutea were found in 77.8% (n = 27) of pregnant females.

A male pup Kuril seal (Phoca vitulina stejnegeri) from Hokkaido, Japan, was observed with a unilateral and total cleft of the primary palate. Complications included a supernumerary tooth, hypoplasia and asymmetry of the face, and deformation of the eyeball and external auditory meatus. An accompanying pneumonia may have resulted from water flowing into the respiratory system due to imperfect closure of the nostril by the cleft. No other abnormalities were found.

Twenty-one species of deer occur in China: one species of Tragulidae, three species of Moschidae and 17 species of Cervidae. The foundation of this review is the research conducted in the early 1940s by Allen, combined with the research and investigation by the authors and other Chinese specialists since that time. This paper focuses on the tentative distribution of these species of deer for future research efforts.

The supernumerary postcanine teeth were examined in the kuril seal (Phoca vitulina stejnegeri), the larga seal (P. largha) and the ribbon seal (P. fasciata). Supernumerary postcanine teeth were found in 6.56%, 6.03% and 11.76% of them respectively. On the other hand, 1.31% of the kuril seal, 0.86% of the larga seal and 11.76% of the ribbon seal were found to have missing teeth. So, in these three species, there is a greater percentage having supernumerary teeth than missing teeth. This is a rare situation in mammals because missing teeth are more common than supernumerary teeth in many species. As the position in which supernumerary postcanine teeth were found are commonly variable, it is thought that the cause of supernumerary postcanine teeth is due to a splitting of the tooth germ rather than atavism in the kuril seal and the larga seal. Also the positions of the supernumerary teeth in the kuril seal are different from the larga seal. This difference is presumed to stem from the differences in the foetal developmental process of the maxilla and mandible of the two species.

Blood samples were taken from 78 wild and 21 farmed sika deer (Cervus nippon yesoensis) using ketamine-xylazine sedation during their excited (82 deer) and resting (17 deer) states. Red cell count (RBC), hemoglobin (Hb), packed cell volume (PCV) and mean corpuscular volume (MCV) were significantly higher and mean corpuscular hemoglobin concentration (MCHC) was lower in excited deer than in resting deer. There was no significant difference in total leukocyte count (WBC) between excited and resting wild males, while a marked increase of WBC with neutrophilia was observed in excited wild females. RBC and PCV were significantly higher and MCH was lower in excited males than in excited females. In wild deer, WBC was significantly higher in females than in males, but there was no significant difference in WBC between farmed males and females. Sex differences in the hematological parameters were not observed in fawns (10 months).

The mitochondrial DNA control region of the sun bear (Helarctos malayanus) was sequenced using 21 DNA samples collected from confiscated sun bears to identify conservation units, such as evolutionarily significant units and management units, in Sarawak, Borneo Island. A total of 10 haplotypes were observed, indicating the presence of at least two lineages in the sun bear population in Sarawak. Presumably, these two lineages could represent evolutionarily significant units. However, the geographical distributions of the two lineages remained unknown due to the lack of information regarding the exact capture locations of the confiscated sun bears. It is essential to elucidate the geographical distributions of these lineages in order to create a proper conservation plan for the sun bears in Sarawak. Therefore, further studies examining the haplotype distributions using DNA samples from known localities are essential.

There are two foci of alveolar echinococcosis (AE) caused by Echinococcus multilocularis in Japan. The first focus is on Rebun Island where AE patients were found from 1937, and the second is in eastern Hokkaido where patients have been found since the 1960s. The origin of the second focus is unknown. To further investigate AE in eastern Hokkaido, wild rodents (Muridae) were captured and examined for infection on Kunashiri Island, which is located 15 km off the northeastern coast of Hokkaido. Metacestodes of E. multilocularis were isolated from two of 31 voles, all of which were identified to be Clethrionomys rufocanus. Mitochondrial DNA sequencing data of recovered cestodes showed total identity with the cestode reported from Hokkaido. These results suggest that E. multilocularis may have been introduced to Hokkaido from Kunashiri Island during or after 1965.

The morphological characteristics of myoepithelial cells and arrectores pilorum muscles were investigated in caudal, metatarsal and preorbital glands of Hokkaido sika deer (Cervus nippon yesoensis Heude, 1884) using immunohistochemistry for alpha-smooth muscle actin. In the metatarsal, preorbital and general skin glands, myoepithelial cell layers continuously embraced the secretory epithelium, while in the caudal gland, discontinuous myoepithelial cell rows surrounded the apocrine tubules. There was a trend that the widths of the myoepithelial cells of the caudal and preorbital glands appeared to be thinner than those of the metatarsal and general skin glands. In the metatarsal gland, the arrectores pilorum muscles were highly developed and considerably larger than those in other skin glands.

The dental neonatal line of the sika deer (Cervus nippon) was identified experimentally using chronological labeling methods. In the enamel, prominent dark lines were observed under transmitted light, and the number of increments between the dark line and labeling line was almost consistent with the day-age at the time of labeling injection. Therefore, we identified the dark line as the enamel neonatal line. In the dentin, the bright line was observed under polarized light. Since the bright line corresponded to the enamel neonatal line, we recognized the bright line as the dentin neonatal line. Neonatal lines intersected with the enamel-dentin junction at approximately one-third cervical in the first molar. Using these features, it would make possible to distinguish the neonatal line in wild sika deer.

We analyzed the localization of steroidogenic enzymes (P450 scc, 3 beta HSD, P450 arom and P450 c17) in the corpora lutea of two Hokkaido sika deer (Cervus nippon yesoensis) during the early mating season. Two corpora lutea were found in each female and the timing of formation of the corpora lutea seemed different. P450 scc, and 3 beta HSD, positive luteal cells were found in both corpora lutea. The existence of two functional corpora lutea from the early mating season through pregnancy suggests that progesterone secreted by two or more corpora lutea is necessary for maintenance of pregnancy in sika deer.

Genetic relationship among Japanese sables, Martes zibellina and the introduced Japanese martens, Martes melampus in northern Japan was revealed by analyzing a 521-524bp DNA sequence from the cytochrome b (112bp)/transfer RNA-threonine (67bp)/tRNA-proline (65bp) and control region (277-280bp) of the mitochondrial genome. Intraspecific differences in sequences of M. zibellina and M. melampus (3.8-15.0% and 1.9-16.4%, respectively) were similar to interspecific differences between these two species (5.8-16.6%). Comparison of sequence data exhibited five haplotypes of M. melampus and four haplotypes of M. zibellina, which clustered into two groups (clusters-A and-B). Cluster-A included two haplotypes of M. melampus and two haplotypes of M. zibellina, whereas cluster-B included three haplotypes of M. melampus and two haplotypes of M. zibellina. Results of this study lead three possible explanations. Firstly, past hybridization between M. zibellina and M. melampus might have occurred. Secondary, these two species might have similar heteroplasmy of mtDNA. Thirdly, these haplotypes might have come from nuclear genome. Although further intensive studies are needed to make a conclusion, detection of hybridization with the Japanese marten are occurred or not is quite important to conserve the Japanese sable.

Skulls and canines of 460 sea otters from Lopatka Cape, Kamchatka, were examined to assess development patterns, individual variation and sexual differences. An allometric formula was applied to morphometrical data, and the relative growth of each character to total length of skull was analyzed. In both sexes, most morphometrical characters ceased growth at about 2 years of age. Canine root length increased rapidly during the first year of life, while crown length decreased due to remarkable wear. There was large individual variation in the feeding and breathing/sniffing apparatus, while there was little variation in braincase size. There were sexual differences in most characteristics, although males and females showed similar growth patterns. The coronoid process of the mandible showed positive allometry in both sexes, and we attributed this finding to feeding habits. The fact that only male mastoids showed positive allometry may be due to the need for male otters to maintain a passing territory.

Scanning electron microscopy for plastic casts and confocal laser scanning microscopy for Villanueva bone-stained ground sections were used together to observe enamel tubules in red kangaroo molars. Although the tubular structures such as terminals, bends, expansions, splits, divergences and rejoinings in this species were within the variations of marsupial species, their morphological characteristics were demonstrated with extremely clear and persuasive images. Thus, the combined observations of plastic casts by scanning electron microscopy and Villanueva bone-stain sections by confocal laser scanning microscopy were found to be of value for the investigation of enamel tubules and tubular structures in other hard tissues.

Reproduction of feral raccoons (Procyon lotor) in Hokkaido, Japan, was examined during a 2-year period by analysis of placental scars or fetuses in the uterus. Of 242 collected females, 69 (29%) were juveniles, 71 (29%) yearlings, and 102 (42%) adults. The pregnancy rate averaged 66% in yearlings and was significantly lower than the 96% average observed in adults (p0.01). Litter size ranged from 1 to 7 offspring per female, and averaged 3.6 in yearlings and 3.9 in adults. There was no significant difference in mean litter size between yearlings and adults. In Hokkaido, the raccoon mating season peaked in February and the majority of litters were born between March and May, similar to patterns described in North America, but some females mated in summer. The reproductive potential of feral raccoons in Hokkaido was similar to that reported in North America. The recent increase in raccoon numbers can be explained by their high productivity. Harvest data suggest that hunting pressure on juveniles is lower than that for older age classes when using box traps in summer. In order to reduce the feral raccoon population, alternative hunting methods that increase juvenile mortality rates are needed.

To develop an easy method of typing of mitochondrial DNA (mtDNA) in Hokkaido brown bears (Ursus arctos yesoensis), the PCR-RFLP technique was improved using four restriction enzymes: Mbo 1, Cfr 13 I, TspE 1, and Fok 1. This approach identified seven groups of mtDNA haplotypes, HB1/2/5-7, HB 3, HB4, HB8/9, HB10/11, HB12 and HB13 from 102 brown bears of northern, central and eastern Hokkaido.

The growth pattern and seasonal weight fluctuations of feral raccoons in Hokkaido were evaluated between 1999 and 2001. The growth rates inbody length and body weight were described for juveniles (young of the year) and yearlings (animals born in the previous season) using the Gompertz growth model. The asymptotic body sizes for males were greater than those for females. Young raccoons born during spring in the study area could potentially grow up to their asymptotic size at the beginning of their first winter, but they would not reach their full adult sizes until at least their second fall. Adult raccoons (animalsor = 2 -year-old) had seasonal weight fluctuations with annual weight loss of 25% to 28% of mean maximum weights in west-central Hokkaido, but these result would be an underestimate of the degree of annual weight fluctuations. Juvenile raccoons can be distinguished from the older animals by measuring body length or body weight during fall in Hokkaido.

This work was designed to observe the dentine incremental lines of the sika deer (Cervus nippon) fawns and to investigate their periodicity using the chronological labeling method with fluorochromes. The incremental lines were observed in decalcified specimens stained by Bodian's silver technique, and the fluorescence-labeled lines were observed in undecalcified and ground specimens. In the silver stained specimens, there were two types of lines, deeply stained thick lines and faintly stained minute regular incremental lines. The intervals and staining intensities of the deeply stained thick lines were very similar to those of the fluorescence-labeled lines in the ground specimens obtained from the same tooth, and hence, it appeared that the both lines were identical. The number of minute incremental lines between the deeply stained thick lines was the same as that of days between the time when each fluorescent labeling injection was made. Therefore, it seemed that each minute incremental line was formed each day. The possibility of age estimation in days using diurnal dentine increments was discussed.

Fecal estradiol concentrations were measured in three captive unmated female sun bears (Helarctos malayanus) from August 1998 to July 1999 in Sarawak, Malaysia and vaginal smears from one of the females was observed in August 1998 and March 1999. A single peak in fecal estradiol concentration was obvious for each bear in August or September 1998, and there was a much higher percentage of superficial vaginal anuclear cells in August 1998 than in March 1999. These results suggest that sun bears in Sarawak are likely to be a seasonal breeder associated with a peak of estrogen production in August or September.

Cranial features (development, individual variation, and sexual dimorphism) were examined from the 23 metrical characters and 2 nonmetrical characters (the degree of closure of the 9 cranial sutures and the presence of sagittal crest) in the two spotted seal specimen groups at the Nemuro Strait, Hokkaido. One specimen group was incidentally taken in the salmon trap nets between 1982 and 1983 (n = 70), and the other was randomly sampled by damage control kill between 1997 and 1998 (n = 82). The development of morphometrical characters of skulls ceased at 5.6, 10.7, 7.9, and 11.9 yr. old, for 1982-83 male, 1982-83 female, 1997-98 male and 1997-98 female, respectively. The sutures were half ankylosed till approximately 10 yr. old in both sexes. The sagittal crest began from about 5 yr. old in male. Individual variation of skull was large in the feeding, breathing, and facial-expression apparatus. On the other hand, the variation of braincase, and skull concerning to the movement of head/neck tended to be small. Only 1997-98 specimens exhibited a sexual dimorphism in skull characters except for the braincase, whereas the dimorphism was not found in 1982-83 specimens. We could not detect the significant difference between two specimen groups, although there were a few differences in characters related to the rostrum and mandible.