Zapus trinotatus

About: Zapus trinotatus is a research topic. Over the lifetime, 9 publications have been published within this topic receiving 532 citations.

Streams over mountains: influence of riparian connectivity on gene flow in the Pacific jumping mouse (Zapus trinotatus).

Abstract: In species affiliated with heterogeneous habitat, we expect gene flow to be restricted due to constraints placed on individual movement by habitat boundaries. This is likely to impact both individual dispersal and connectivity between populations. In this study, a GIS-based landscape genetics approach was used, in combination with fine-scale spatial autocorrelation analysis and the estimation of recent intersubpopulation migration rates, to infer patterns of dispersal and migration in the riparian-affiliated Pacific jumping mouse (Zapus trinotatus). A total of 228 individuals were sampled from nine subpopulations across a system of three rivers and genotyped at eight microsatellite loci. Significant spatial autocorrelation among individuals revealed a pattern of fine-scale spatial genetic structure indicative of limited dispersal. Geographical distances between pairwise subpopulations were defined following four criteria: (i) Euclidean distance, and three landscape-specific distances, (ii) river distance (distance travelled along the river only), (iii) overland distance (similar to Euclidean, but includes elevation), and (iv) habitat-path distance (a least-cost path distance that models movement along habitat pathways). Pairwise Mantel tests were used to test for a correlation between genetic distance and each of the geographical distances. Significant correlations were found between genetic distance and both the overland and habitat-path distances; however, the correlation with habitat-path distance was stronger. Lastly, estimates of recent migration rates revealed that migration occurs not only within drainages but also across large topographic barriers. These results suggest that patterns of dispersal and migration in Pacific jumping mice are largely determined by habitat connectivity.

Use of Riparian and Upland Habitats by Small Mammals

Abstract: Mark-recapture was conducted from 1981 through 1983 in the Cascade Range of Oregon to examine the use of riparian and upland habitats by small mammals. Both number of individuals and species richness were greater in riparian than in upland areas. Because of the occurrence of several less-commonly captured species in riparian locations, species evenness was greatest in the upland. Among Insectivora, Sorex monticolus and S. trowbridgii were captured most often on riparian sites. Among insectivores adult males weighed more in riparian zones. Three rodents ( Peromyscus maniculatus, Microtus oregoni , and Zapus trinotatus ) were captured more frequently in riparian habitats; two rodents ( Tamias townsendii and Clethrionomys californicus ) were captured more frequently in upland habitats. Among all rodents, except Z. trinotatus , adult males weighed more in riparian areas. Mustela erminea was captured more frequently in riparian sites. Eight species had greater numbers of adults in breeding condition in riparian than in upland habitats. Conversely, six species had greater numbers of juveniles in the upland. Data from several species, including T. townsendii, P. maniculatus, Z. trinotatus , and Glaucomys sabrinus , indicated that riparian habitats act as a species source and upland areas act as a dispersal sink.

Plant and Mannal Changes on a Clearcut In West‐Central Oregon

Abstract: Plant composition and coverage and small mammal populations were compared in virgin forest (control) and clearcut (experimental) areas from April 1954 to October 1965. Changes in ground cover vegetation were modest on the control area but marked on the experimental area. A late fall burn on the experimental area may have retarded herbaceous plant establishment. Nearly half of the herbaceous species were invaders not found in the virgin Douglas—fir (Pseudotsuga menziesii) forest. Ground plant coverage was less than 23% in the virgin forest; 1 year after the clearcut area was burned, the cover was 2%; and by 10 years it was above 53%. Woody plant coverage (mostly sprouts) was slightly more abundant the first 2 years after burning. Herbaceous species then became dominant for a 3—year period, after which woody plants gradually gained dominance. Deer mice (Peromyscus maniculatus) increased on the experimental area soon after the burn. The populations varied from an estimated 0.9 to 12.8 animals per acre and fluctuated widely and irregularly. Townsend's chipmunk (Eutamias townsendii), Oregon vole (Microtus oregoni), and snowshoe hare (Lepus americanus) populations also increased on the area at different periods after the burn. Trownbridge's shrews (Sorex trowbridgii), vagrant shrews (Sorex vagrans), and ermine (Mustela erminea) were present on both areas in relatively low numbers. Redback voles (Clethrionomys occidentalis), Douglas' squirrels (Tamiasciurus douglasii), and northern flying squirrels (Glaucomys sabrinus) were not found on the clearcut. California ground squirrels (Spermophilus beecheyi) migrated to the clearcut and established a modest population. Richardson's voles (Microtus richardsoni), jumping mice (Zapus trinotatus), bushy—tailed woodrats (Neotoma cinerea), and a pika (Ochotona princeps) were visitors.

The genetic effects of ecological disturbance: flooding in jumping mice.

Abstract: Pacific jumping mice (Zapus trinotatus) live in riparian habitats that are discontinuously distributed and subject to regular flooding. Both of these characteristics have a spatial component. Habitat‐restricted dispersal frequently leads to spatial genetic structure among individuals, and flooding often imposes spatially specific mortality. Here I report that following a severe flood, an interaction between these factors resulted in an immediate reduction of genetic diversity and genetic divergence of the postflood population. Survival was spatially biased toward more closely related individuals, and this was propagated throughout the postflood population by changes in reproduction. Not only did the number of closely related breeding pairs increase, but so did the production of offspring by individuals. These changes precipitated strong genetic effects, including a reduction in observed heterozygosity, an increase in relatedness, a doubling of inbreeding levels, and significant genetic divergenc...

Early Pleistocene zapodid rodents from the Java Local Fauna of north-central South Dakota

Abstract: Zapodid rodents are described from the early Pleistocene Java Local Fauna, Walworth County, South Dakota. The fauna includes a new species of Zapus related to the extinct Z. sandersi. The fossil record of Zapus is briefly reviewed, and the M1s of Z. rinkeri and an undescribed species from the Wendell Fox Pasture Local Fauna are illustrated for the first time. Zapus trinotatus and Z. princeps probably represent a clade distinct from other Zapus species, but relationships among the remaining species are difficult to determine. Two additional zapodids represent new genera and species. One appears to be remotely related to the Pliocene Pliozapus or Protozapus and the other is a tiny, presumably carnivorous sicistine linked to Old World striped mice of the genus Sicista. This is the first record of a Pleistocene sicistine from North America.