Genetic relatedness and home-range overlap among female black bears (Ursus americanus) in northern Ontario, Canada

The degree of philopatry exhibited by females in an unhunted black bear (Ursus americanus) population occupying the Chapleau Crown Game Preserve in northern Ontario was examined. A truncated kernel estimator was used to identify home-range use. Pairs of adult females were categorized as having home ranges that had moderate overlap or low overlap or were adjacent and non-overlapping or non-adjacent and non-overlapping. Females had low overlap with 6.4 other females, on average, and moderate overlap with 1.5 females. The degree of philopatry was assessed using two methods, each of which was used in an attempt to examine home-range overlap and average genetic relatedness. Relatedness among bears was determined from DNA fingerprints, using an alkaline phosphatase labelled multilocus probe and chemiluminescence detection. The first method involved choosing the 3 oldest females in the region to represent potential matriarchs, and all neighbouring females were identified (n = 8, 8, and 11). DNA fingerprints from each matriarch were compared with those of her neighbours. Average band-sharing coefficients and relatedness estimates within the groups did not reveal patterns of close kinship. The second method involved band-sharing comparisons among pairs of females from each of the 4 home-range categories (n = 12, 57, 80, and 21). Again, no relationship between spatial proximity and average genetic relatedness (range 0.032-0.120) was suggested. The extensive home-range overlap exhibited by this population is not a consequence of natal philopatric tendencies.

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Genetic relatedness and home-range overlap among female black bears (Ursus americanus) in northern Ontario, Canada

Canadian Journal of Zoology ◽

10.1139/cjz-76-8-1511 ◽

1998 ◽

Vol 76 (8) ◽

pp. 1511-1519 ◽

Cited By ~ 11

Author(s):

Anita Schenk ◽

Martyn E. Obbard ◽

Kit M. Kovacs

Keyword(s):

Home Range ◽

Genetic Relatedness ◽

Ursus Americanus ◽

Black Bears ◽

Northern Ontario ◽

Home Range Overlap ◽

Range Overlap

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Black Bear Home Range Overlap in North Carolina and the Concept of Home Range Applied to Black Bears

Bears Their Biology and Management ◽

10.2307/3872630 ◽

1987 ◽

Vol 7 ◽

pp. 235 ◽

Cited By ~ 8

Author(s):

Roger A. Powell

Keyword(s):

North Carolina ◽

Home Range ◽

Black Bear ◽

Black Bears ◽

Home Range Overlap ◽

Range Overlap

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Genetic relatedness cannot explain social preferences in black-and-white ruffed lemurs (Varecia variegata)

10.1101/799825 ◽

2019 ◽

Author(s):

Andrea L Baden ◽

Timothy H Webster ◽

Brenda J Bradley

Keyword(s):

Home Range ◽

Social Preferences ◽

Genetic Relatedness ◽

Space Use ◽

Social Attraction ◽

Spatial Overlap ◽

Home Range Overlap ◽

Black And White ◽

Range Overlap ◽

Social Association

ABSTRACTFission-fusion social dynamics are common among a number of vertebrate taxa, and yet the factors shaping these variable associations among subgroup members have not been widely addressed. Associations may occur simply because of shared habitat preferences; however, social ties may also be influenced by genetic relatedness (kinship) or social attraction. Here, we investigate the association patterns of wild black-and-white ruffed lemurs, Varecia variegata, in Ranomafana National Park, Madagascar using behavioural, spatial (home range), and genetic data from twenty-four individually identified animals. We collected 40,840 records of group composition over a 17-month period and from this calculated pairwise association indices. We also used ranging coordinates and genetic samples to estimate patterns of spatial overlap and kinship, and then related these measures to patterns of affiliation. From these analyses, we found that dyadic ruffed lemur social associations were generally sparse and weak; that home range overlap was minimal; and that average relatedness within the community was low. We found no evidence that kinship was related to patterns of either spatial overlap or social association; instead, associations were primarily driven by space use. Moreover, social preferences were unrelated to kinship. While home range overlap explained most of the variation seen in social association, some variation remains unaccounted for, suggesting that other social, ecological, and biological factors such as shared resource defense or communal breeding might also play a role in social attraction. Our results further highlight the need to consider individual space use and nuances of species behavior when investigating social preference and social association more generally.

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Sex-Segregated Range Use by Black-and-White Ruffed Lemurs (Varecia variegata) in Ranomafana National Park, Madagascar

Folia Primatologica ◽

10.1159/000510965 ◽

2020 ◽

pp. 1-33

Author(s):

Andrea L. Baden ◽

Jelisa Oliveras ◽

Brian D. Gerber

Keyword(s):

Home Range ◽

National Park ◽

Social Groups ◽

Day Length ◽

Ranomafana National Park ◽

Home Range Overlap ◽

Range Use ◽

Black And White ◽

Varecia Variegata ◽

Range Overlap

Ranging behavior is one important strategy by which nonhuman primates obtain access to resources critical to their biological maintenance and reproductive success. As most primates live in permanent social groups, their members must balance the benefits of group living with the costs of intragroup competition for resources. However, some taxa live in more spatiotemporally flexible social groups, whose members modify patterns of association and range use as a method to mitigate these costs. Here, we describe the range use of one such taxon, the black-and-white ruffed lemur (<i>Varecia variegata</i>), at an undisturbed primary rain forest site in Ranomafana National Park, Madagascar, and characterize sex differences in annual home range area, overlap, and daily distances traveled. Moreover, we characterize seasonal variability in range use and ask whether ranging behaviors can be explained by either climatic or reproductive seasonality. We found that females used significantly larger home ranges than males, though sexes shared equal and moderate levels of home range overlap. Overall, range use did not vary across seasons, although within sexes, male range use varied significantly with climate. Moreover, daily path length was best predicted by day length, female reproductive state, and sex, but was unrelated to climate variables. While the patterns of range use and spatial association presented here share some similarities with “bisexually bonded” community models described for chimpanzees, we argue that ruffed lemurs best conform to a “nuclear neighborhood” community model wherein nuclear (core) groups share the highest levels of home range overlap, and where these groups cluster spatially into adjacent “neighborhoods” within the larger, communally defended territory.

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