Topic
Sciurus lis
About: Sciurus lis is a research topic. Over the lifetime, 24 publications have been published within this topic receiving 231 citations.
Papers
TL;DR: The effects of the urban–rural–forest gradient and spatial scale on the distributions of large and mid-sized mammals in the world's largest metropolitan area in warm-temperate Asia are evaluated using nonspecific camera-trapping along two linear transects.
Abstract: Urbanization may alter mammal assemblages via habitat loss, food subsidies, and other factors related to human activities. The general distribution patterns of wild mammal assemblages along urban–rural–forest landscape gradients have not been studied, although many studies have focused on a single species or taxon, such as rodents. We quantitatively evaluated the effects of the urban–rural–forest gradient and spatial scale on the distributions of large and mid-sized mammals in the world's largest metropolitan area in warm-temperate Asia using nonspecific camera-trapping along two linear transects spanning from the urban zone in the Tokyo metropolitan area to surrounding rural and forest landscapes. Many large and mid-sized species generally decreased from forest landscapes to urban cores, although some species preferred anthropogenic landscapes. Sika deer (Cervus nippon), Reeves' muntjac (Muntiacus reevesi), Japanese macaque (Macaca fuscata), Japanese squirrel (Sciurus lis), Japanese marten (Martes melampus), Japanese badger (Meles anakuma), and wild boar (Sus scrofa) generally dominated the mammal assemblage of the forest landscape. Raccoon (Procyon lotor), raccoon dog (Nyctereutes procyonoides), and Japanese hare (Lepus brachyurus) dominated the mammal assemblage in the intermediate zone (i.e., rural and suburban landscape). Cats (feral and free-roaming housecats; Felis catus) were common in the urban assemblage. The key spatial scales for forest species were more than 4000-m radius, indicating that conservation and management plans for these mammal assemblages should be considered on large spatial scales. However, small green spaces will also be important for mammal conservation in the urban landscape, because an indigenous omnivore (raccoon dog) had a smaller key spatial scale (500-m radius) than those of forest mammals. Urbanization was generally the most important factor in the distributions of mammals, and it is necessary to consider the spatial scale of management according to the degree of urbanization.
80 citations
TL;DR: Seeds of the Japanese walnut are usually scatter-hoarded by two rodent species, the Japanese squirrel Sciurus lis and the field mouse Apodemus speciosus, but only by the latter in several areas where S. lis is absent, which could affect the evolution of seed size.
Abstract: Seeds of the Japanese walnut, Juglans ailanthifolia, are usually scatter-hoarded by two rodent species, the Japanese squirrel Sciurus lis and the field mouse Apodemus speciosus, but only by the latter in several areas where S. lis is absent. We examined seed-size-mediated interactions of these three species across a wide geographic range. Field tracking of walnuts with miniature radio-transmitters revealed that squirrels hoarded larger seeds more frequently and at greater distances than smaller seeds. In contrast, mice hoarded smaller seeds more frequently and transported them farther than larger seeds. These seed dispersers could affect the evolution of seed size because seeds hoarded at sites farther from source trees are known to survive better until germination and as seedlings. We expect that larger seeds may be advantageous in regeneration if the main seed dispersers are squirrels, whereas smaller seeds may be advantageous if mice are the dominant dispersers. These predictions were supported by the fact that seed size was smaller on islands inhabited only by mice and at the edge of the squirrel distribution, compared to areas where mice and squirrels are both common.
41 citations
TL;DR: Phylogenetic trees constructed by sequence data indicated that two genera of flying squirrels were clustered in a group distinct from non-flying squirrels, suggesting a possible monophyletic relationships of these flying Squirrels.
Abstract: In order to investigate phylogenetic relationships of the family Sciuridae living in Japan, we sequenced partial regions (379 bases) of mitochondrial 12S rRNA genes in six species of Japanese and other Asian squirrels. Phylogenetic trees constructed by sequence data indicated that two genera of flying squirrels (Petaurista and Pteromys) were clustered in a group distinct from non-flying squirrels, suggesting a possible monophyletic relationships of these flying squirrels. The evolutionary distance between the Japanese squirrel (Sciurus lis) from Honshu island and the Eurasian red squirrel (Sciurus vulgaris) from Hokkaido island was comparable to intraspecific distances of the remaining species examined.
36 citations
TL;DR: Of 60 hoarded seeds, 38 were retrieved by squirrels later, but 15 were stolen by wood mice, so after all, 7 seeds were not retrieved until May 1993.
Abstract: Walnut seeds (Juglans ailanthiforia Carr.) hoarded by Japanese squirrels (Sciurus lis Temminck) were tracked using miniature radio transmitters. A total of 100 seeds with transmitters were provided on the feeding stands in the walnut forest from September to December, 1992. Squirrels ate 35 seeds without hoarding, and 60 were scatter-hoarded. Five seeds were eaten by wood mice (Apodemus speciosus Temminck). The distance from the feeding stand to cache sites ranged from 1 to 62 m with the mean 18 m. Of 60 hoarded seeds, 38 were retrieved by squirrels later, but 15 were stolen by wood mice. After all, 7 seeds were not retrieved until May 1993.
32 citations
1 Jan 2004
TL;DR: In this article, the authors used a logistic regression model to predict the probability of occurrence of the Formosan squirrel throughout Kanagawa Prefecture and found that the assemblage of large woods along the Sagami River and Sagami Bay would be conductive to increasing its population and expanding its distribution.
Abstract: There is growing concern about the impact on the habitat of the native Japanese squirrel (Sciurus lis) in relation to the spread of the Formosan squirrel (Callosciurus erythraeus thaiwanensis), an alien species that was introduced and became naturalized in Kamakura City, Kanagawa Prefecture, in the 1950s. We used a logistic regression model to predict the probability of occurrence of the Formosan squirrel throughout Kanagawa Prefecture. Wooded areas, the proportion of cultivated fields surrounding a wood and the proportion of evergreen trees in a wood, factors that influence the presence of Formosan squirrels, were used as environmental variables in the model. As a result, we found that woods suitable for the Formosan squirrel were distributed not only around Kamakura, which Formosan squirrels currently inhabit, but throughout Kanagawa Prefecture. Furthermore, a comparison of its current habitat and its predicted suitable habitat suggested that the assemblage of large woods along the Sagami River and Sagami Bay would be conductive to increasing its population and expanding its distribution to western Kanagawa. Because there are forests in western Kanagawa which are extensive and are expected to be a suitable habitat for the Formosan squirrel, we should prevent Formosan squirrels from invading the west side of the Sagami River.
29 citations
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| 2021 | 1 |
| 2020 | 1 |
| 2016 | 1 |
| 2013 | 1 |
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| 2010 | 1 |