Mammal Study
Volume 45, Issue 2, 2020
Volumes & issues:
-
ORIGINAL PAPERS
-
-
The Role of Postcranial Skeleton Morphology in Species Identification and Phylogeny Inferences: Gerbillinae (Rodentia: Muridae) as a Case Study
View Description Hide DescriptionAbstract.Identification of rodents usually has been done based on cranial and dental characters. Postcranial skeleton has been ignored in spite of its importance in archaeozoology for identification of skeletal remains. Herein, we intended to determine the importance of postcranial skeleton in identification and classification of gerbilline rodents in Iran. Different skeletal parts of 82 specimens belonged to five genera and ten species were extracted using papain digestion. A total of 62 characters with 142 character states were defined as informative postcranium variations for separating taxa. Results showed that reconnaissance of specimens belonging to the genera Tatera, Gerbillus, and Rhombomys was possible using morphological characters of vertebral column and thorax, pectoral girdle and forelimb, and pelvic girdle and hindlimb. Moreover, these morphological characters could be useful for identification of Meriones species. For cladistic analyses, the data matrix scored for two characters of external anatomy, 20 of vertebral column, 11 of pectoral girdle, seven of pelvic girdle, ten of forelimb and 12 of hindlimb was provided. The cladogram resulted from strict consensus method, employed in PHYLIP, was comparable with phylogenetic trees inferred from cranial morphology and molecular studies. Finally, an identification key for Gerbillinae was provided based on postcranium characteristics.
-
Spatiotemporal Patterns of Latrine-Site Use by Small-Clawed Otters in a Heterogeneous Rice Field Landscape
View Description Hide DescriptionAbstract.Tropical rice fields with asynchronous growth stages provide a good model to investigate the effects of landscape heterogeneity on the use of agricultural landscapes by wildlife. The small-clawed otter (Aonyx cinereus) uses rice fields as latrine sites in Southeast Asia. Through a 53-week survey of latrine sites, we analyzed the spatiotemporal patterns of latrine-site use by small-clawed otters in an asynchronous rice field in West Sumatra, Indonesia. Based on a generalized linear mixed model incorporating local environmental factors, otter latrine-site visitation was positively associated with the vegetative stage of rice cultivation and the biomass of a major prey item, the golden apple snail (Pomacea canaliculata). The vegetative stage of rice cultivation and golden apple snail biomass were closely associated with deep water in rice fields; therefore, water availability in rice fields is likely important in determining the spatiotemporal patterns of small-clawed otter latrine-site use in the asynchronous rice field landscape. To consistently provide latrine sites for small-clawed otters, we recommend that asynchronous rice cultivation be maintained, or zoning of synchronous and asynchronous rice cultivation areas be planned in the region.
-
Population Characteristics and Microhabitat Preference of Critically Endangered Kondana Soft-Furred Rat (Millardia kondana) in the Northern Western Ghats, India
View Description Hide DescriptionAbstract.Millardia kondana is a Critically Endangered species of rat, known only from four localities in India. All these sites were facing growing threats from grazing, fire, and infrastructure-, housing-, and tourism-development. Therefore, we conducted this study to examine the spatiotemporal variation in population density and size and habitat preference of M. kondana. We carried out live trapping of M. kondana at three sites and recorded microhabitat covariates which were likely to influence its abundance. Spatially explicit capture-recapture models (SECR) were used to estimate density of the species. In total, 210 individuals of M. kondana were captured for 301 times in 2700 trap night efforts with trapping success of 11.15 rats/100 trap nights. Density estimates (2.01–10.76 rats/ha) and population estimates (20.24–246.34 individuals) showed substantial spatiotemporal variation. M. kondana appeared to be fast breeding species with a short life span. Model predictions indicated that the species preferred open habitats. Its abundance was positively influenced by increasing perennial herb density (PHD) and herb height (HH). Thus, the conversion of open habitats into forested habitats or human settlements need to be stopped to conserve this species.
-
Density Estimates and Habitat Preferences of the European Hare (Lepus europaeus) on Mountainous Areas in Italy
View Description Hide DescriptionAbstract.The European hare (Lepus europaeus) populations are declining throughout Europe due to intensive agriculture and hunting pressure. In Italy, information on this species is biased and focused on plain terrains, while data over mountains are scant. The study aimed to fill such a research gap, providing estimates on the population density and habitat preferences on a suboptimal mountainous environment in Italy, using the standardised pellet-count method. One protected area and two hunting areas were surveyed between June and August 2017, with 117 plots randomly checked for faecal pellets. The estimated density on mountainous territories ranged from 16 to 23 individuals/km2, which resulted high for a non-favourable environment. Land cover was the most important predictor in the model, with arable lands and areas with sparse vegetation as the preferred land use. Habitat selection drove the altitudinal distribution of the hare, with high elevations preferred over lower altitude. Steepest slope and NE, SW, and West-faced plots were displaying less probability to find pellets. The density in the protected and hunting areas was similar, with the hunting ban being the least significant predictor. Despite the climate and altitude, the environmental heterogeneity of the Italian Apennine might offer a good-quality habitat for the European hare.
-
Bi-Directional Movement of Deer between Tomogashima Islands and the Western Part of the Kii Peninsula, Japan, with Special Reference to Hybridization between the Japanese Sika Deer (Cervus nippon centralis) and the Introduced Exotic Deer
View Description Hide DescriptionAbstract.Deer have been artificially introduced into many countries that are not within their native range. In some cases, they have disturbed the natural ecosystem in the invaded area. On Okinoshima Island in Wakayama Prefecture, Japan, exotic deer were introduced from Taiwan in 1955 and have since bred in the wild, raising concerns about their invasion into the habitats of, and hybridization with, the native Japanese sika deer. To determine the extent of gene introgression, we investigated the population structure of deer on Okinoshima Island and the surrounding areas, including the islands of Awajishima and Jinoshima, and the mainland area in the western Kii Peninsula. Genetic analyses using microsatellite and mitochondrial DNA markers revealed that both exotic deer and Japanese sika deer inhabited Jinoshima Island. On the other hand, one of the individuals captured on the mainland was a first-generation hybrid between the exotic and native deer. These results suggest the bi-directional movement of the exotic and native deer between the islands and the mainland, with the potential for hybridization.
-
A Fin Whale from the Holocene (Quaternary) of Osaka City, Japan
View Description Hide DescriptionAbstract.Specimen number OMNH-QV 4815, including the skull, mandibles, fused basihyal and thyrohyal, vertebrae, ribs, and scapula from the Namba Formation (Holocene), in Osaka City, Japan is identified as Balaenoptera physalus by having the thick anteriorly projected and laterally narrower basihyal and thyrohyal complex, and slender mandibles with laterally tilted coronoid processes. OMNH-QV 4815 is the second remain of the species. Such records will help to expand history of modern species back through the Pleistocene to Holocene.
-
Age- and Sex-Associated Differences in the Diet of the Asian Black Bear: Importance of Hard Mast and Sika Deer
View Description Hide DescriptionAbstract.In the context of reducing human–bear conflict, understanding potential foraging variation within a bear population yields insights into differences in foraging strategy according to an individual's sex and age. Stable isotope analyses reveal information regarding assimilated dietary components. To confirm the foraging variation of Asian black bears and assess its underlying factors, we conducted stable isotope analysis of hair samples. We constructed linear mixed-effect models to examine the effects of sex, age, and hard mast abundance on bear diet. Furthermore, we used stable isotope data on food resources to estimate bear diets from isotopic mixing models to evaluate differences in dietary components among age–sex classes. During the reproductive season, δ 15N values were positively correlated with bear age, and dietary deer fraction was the highest for adult males. Our results also showed that during the hyperphagia season, bears were mostly dependent on hard mast, regardless of its abundance. However, δ 15N values of bears were higher during poor mast years than when mast was plentiful, thus implying that bears consume increased proportions of deer and/or insects (e.g., Vespidae) in poor mast years. Our results indicate that feeding strategies in Asian black bears differ according to age–sex classes and seasons.
-
-
RAPID COMMUNICATION
-
-
Records of Sika Deer Cervus nippon from the Southern Kuril Islands in 1986–2019, with Special Reference to a Continuous Record of Living Deer on Kunashir Island Since 2017
View Description Hide DescriptionAbstract.The sika deer (Cervus nippon) is native to eastern Asia and commonly occurs on Hokkaido Island, northern Japan. The nearby localities of the southern Kuril Islands, located east of Hokkaido, have not been regarded as part of the sika deer's regular range, despite isolated observations and trace evidence described before 2017. Here we consolidate the information of the sika deer in the southern Kuril Islands since 1986 with new information that establishes a continuous record of living sika deer on Kunashir Island from 2017 to 2019.
-
-
ERRATUM
-
-
Errata
View Description Hide Description
-