Mammal Study
Volume 36, Issue 1, 2011
Volumes & issues:
-
Original papers
-
-
Winter Food Abundance for Japanese Monkeys in Differently Aged Japanese Cedar Plantations in Snowy Regions
View Description Hide DescriptionAbstract.Plantation areas of Japanese cedar (Cryptomeria japonica) have often been recognized as low-quality habitats for Japanese monkeys (Macaca fuscata) due to the lack of food resources, although empirical studies on this are few, especially in cool-temperate forests. For monkeys, winter is the bottleneck season for food availability. Hence, we evaluated the monkeys' selectivity of winter food tree species by counting their feeding traces in 2008 and 2009; we then compared the number and variety of winter food resources among several forest sites comprising differently aged cedar plantations——with primary beech forests as a control area——in heavy snow regions of the northeastern Shirakami Mountains. We noted that (1) monkeys tended to prefer shade-intolerant trees as food resources; (2) the stem density and variety of such trees in plantations commonly decreased with increasing forest age; (3) dominant cedar tree thinning effectively increased the preferable food resources for monkeys; and (4) the stem density and variety of food resources in the plantations were greater than those in primary beech forests. These results indicated that cedar plantation areas are not always low-quality habitats for monkeys in cool-temperate forests, as long as appropriate cedar tree thinning for timber production is implemented.
-
Taxonomic Status of Apodemus semotus in Taiwan by Morphometrical Comparison with A. draco, A. peninsulae and A. latronum in China, Korea and Myanmar
View Description Hide DescriptionAbstract.Apodemus semotus in Taiwan was compared with A. draco, A. peninsulae and A. latronum in cranial and external measurements of 726 museum specimens in order to establish its taxonomic status. The latter three species identified were composed of 14 areas in 105 localities of China, Korea, and Myanmar. A group of semotus, draco and peninsulae was discriminated from latronum by the relationship between the incisive foramen length and ML (=the upper molar row length) in averages of adults. Excepting latronum, a group of semotus and draco was distinguished from peninsulae by the relationship between I-M3 (=the distance between the anterior-most point of the incisor and the posterior-most edge of the third upper molar) and ““ratio of the skull”” {=(the distance between the occipital condyle and the anterior edge of the first upper molar) —— ML]/[(I-M3) —— ML]} in averages of adults. Apodemus semotus was located along a regression line for 11 areas of A. draco in log scale relationships between I-M3 and the head and body length or between I-M3 and the tail length in averages of adults. Apodemus semotus in Taiwan did not differ statistically in averages of adults from Areas 1 (Kangding and Gongga Shan), J (Emei Shan and Guancunba) and K (Yangtze River and others) of A. draco, the southwest of Sichuan, China, among which Area K showed similar proportion with A. semotus except for some measurements. It was concluded that Apodemus semotus in Taiwan is designated as A. draco.
-
How Low Quality Foods Sustain High Density Sika Deer (Cervus nippon) Population in Heavily Grazed Habitat?: Comparison of Intake, Digestibility and Feeding Activities between the Deer Fed High and Low Quality Food
View Description Hide DescriptionAbstract.Sika deer (Cervus nippon) populations continue to survive at a relatively high density in heavily grazed habitats, where preferable plants have been decreased. To clarify the contradiction concerning the relation between food quality and carrying capacity, we compared the nutrition contents of original food and remaining available food, and experimentally tested the prediction that the low quality foods may increase carrying capacity through a reduction of food intake. High quality foods have been decreasing, and the remaining available foods were low quality foods with low crude protein. We quantified the amount of intake and digestibility of alfalfa as a high quality food and timothy as a low quality food, and measured the feeding activities. The dry matter intake and digestibility of timothy were lower than those of alfalfa. Additionally, the deer fed timothy ruminated a longer time than the deer fed alfalfa. Our results indicate that low quality food restricted the amount of intake. The low quality foods may increase carrying capacity through a reduction of the food intake, on the condition that the amount of the low quality food resource is similar to that of the high quality food resource.
-
Variation in Maize Consumption by Brown Bears (Ursus arctos) in Two Coastal Areas of Hokkaido, Japan
View Description Hide DescriptionAbstract.We measured carbon and nitrogen stable-isotope ratios in the livers of 130 brown bears (Ursus arctos) killed by hunters in two coastal areas of Hokkaido, Japan, from 2003 to 2004 to analyze the diets of individual bears, particularly maize. In both study areas, bears suspected of damaging maize, whose diets were higher in the C4 plant component, were mainly observed during late summer and autumn. Wide variation in the C4 plant component indicated that individual bears have differing degrees of dependence on maize, suggesting differential foraging behavior among the individual bears. We found that a stable-isotope ratio analysis of individual Hokkaido brown bears can serve as a tool to review the effectiveness of control killing and to monitor trends in maize consumption by local populations of bears.
-
Identification and Molecular Variations of CAN-SINEs from the ZFY Gene Final Intron of the Eurasian Badgers (Genus Meles)
View Description Hide DescriptionAbstract.The short interspersed nucleotide elements (SINEs) are specific to the taxa and thought to be one of powerful phylogenetic gene markers. Especially, the SINE sequences, which exist uniquely in genome of order Carnivora, are named CAN-SINEs. Among the Eurasian badgers (genus Meles), a member of the family Mustelidae in order Carnivora, the Japanese badger (M. anakuma) was previously reported to have an insertion of CAN-SINE in the final intron of the zinc finger protein gene on Y chromosome (ZFY). In the present study, we examined occurrence of the CAN-SINE of the ZFY final intron in the Eurasian badgers, and three continental and four Japanese haplotypes were identified from a total of 40 male badgers. Among the Eurasian badger CAN-SINEs, a 12-bp deletion specific to the Japanese haplotypes was found, whereas the 12-bp region (non-deletion) in the continental haplotypes consisted of one 6-bp direct repeat and 6-bp microsatellite-like sequences. Moreover, the continental haplotypes were phylogenetically divided into three lineages: eastern Eurasia, Caucasus and western Eurasia. These genetic differentiations supported the classification recently proposing that genus Meles are grouped into the European badger (M. meles), the Southwest Asian badger (M. canescens), the Northwest & Central Asian badger (M. leucurus) and the Japanese badger (M. anakuna). In addition, the number of adenines in the poly A/T rich tails was polymorphic among all lineages of Eurasian badgers, and geographically variable within the Japanese badgers.
-
-
Short communications
-
-
Nesting Characteristics of Harvest Mice (Micromys minutus) in Three Types of Japanese Grasslands with Different Inundation Frequencies
View Description Hide Description -
Swim Speed and Acceleration Measurements of Short-Finned Pilot Whales (Globicephala macrorhynchus) in Hawai'i
View Description Hide Description -
Origin of Callosciurus erythraeus Introduced into the Uto Peninsula, Kumamoto, Japan, Inferred from Mitochondrial DNA Analysis
View Description Hide Description
-