Habitat preferences of medium/large mammals in human disturbed forests in Central Japan

Habitat selection by non-native masked palm civets in a Japanese rural landscape, incorporating individual differences

Animals that succeed as non-native species may have highly plastic characteristics. We conducted a radio telemetry survey for introduced masked palm civets (Paguma larvata), which inhabit rural landscapes in almost all of Japan, to clarify their habitat selection and intraspecific variation. We compared two generalized linear mixed models, one that did not consider individual differences and another that did, which indicated the importance of incorporating individual differences for evaluating habitat selection by this species. We obtained results of habitat selectivity for all individuals (i.e., common effect on the species) and for each individual using coefficients of fixed effects or fixed effects with random effects. Masked palm civets significantly selected deciduous broad-leaved forests, artificial structures, rice fields, and orchards as a common effect for all individuals. However, these habitats were not necessarily selected as a significant effect for each individual. Deciduous broad-leaved forests and artificial structures were more important than other habitats. The wide range of possible environments and the plasticity of habitat selection shown in this study may partly explain the success of this species in expanding its distribution in Japan.

Possible transmission of Sarcoptes scabiei between herbivorous Japanese serows and omnivorous Caniformia in Japan: a cryptic transmission and persistence?

Background

Two transmission patterns of Sarcoptes scabiei in host mammal communities have been reported based on microsatellite-level genetic studies in the last two decades. While one involves restrictions among different host taxa, the other is associated with predator–prey interactions between different host taxa. In contrast to these observations, the present study reports a possible irregular case of transmission of S. scabiei between herbivorous Japanese serow and omnivorous Caniformia mammals in Japan, though under very weak predator–prey relationships.

Methods

DNA from 93 Sarcoptes mites isolated from omnivorous Caniformia (such as the domestic dog, raccoon dog, raccoon and Japanese marten), omnivorous Cetartiodactyla (wild boar) and herbivorous Cetartiodactyla (Japanese serow) in Japan were analyzed by amplifying nine microsatellite markers. Principal components analyses (PCA), Bayesian clustering analyses using STRUCTURE software, and phylogenetic analyses by constructing a NeighborNet network were applied to determine the genetic relationships among mites associated with host populations.

Results

In all the analyses, the genetic differentiation of Sarcoptes mites from wild boars and Japanese serows was observed. Conversely, considerably close genetic relationships were detected between Caniformia-derived and Japanese serow-derived mites. Because the predator–prey interactions between the omnivorous Caniformia and herbivorous Japanese serow are quite limited and epidemiological history shows at least a 10-year lag between the emergence of sarcoptic mange in Japanese serow and that in Caniformia, the transmission of S. scabiei from Caniformia to Japanese serow is highly suspected.

Conclusions

The close genetic relationships among mites beyond Host–taxon relationships and without obvious predator–prey interactions in Caniformia and Japanese serow deviate from previously reported S. scabiei transmission patterns. This type of cryptic relationship of S. scabiei populations may exist in local mammalian communities worldwide and become a risk factor for the conservation of the remnant and fragmented populations of wild mammals.

Electronic supplementary material

The online version of this article (10.1186/s13071-019-3630-5) contains supplementary material, which is available to authorized users.