Population density and habitat use of two sympatric small cats in a central Indian reserve

Studies on carnivores are skewed toward larger species in India, limiting ecological information of the smaller ones. Basic ecological understanding like population density, distribution, habitat-use patterns of small carnivores is lacking. This inadequate knowledge has led to disagreement between conservation approaches in different landscapes. Honey badgers (Mellivora capensis) are cryptic carnivores distributed across large areas of Africa and Asia; however, fundamental ecological knowledge is scarce. The species is thought to exist at low population densities throughout its range. We used a large camera trap dataset from a tiger reserve in Maharashtra State, India to understand the population density, habitat preference, and diel activity pattern of the species. We applied an extension of the spatial count model for the estimation of population. Habitat preference analyses were carried out using generalized linear models and activity patterns were analyzed using kernel-density functions. The population density was estimated as 14.09 (95% CI 10–22.25) individuals per 100 km2. Habitat use revealed a positive association with forest cover and negative association with elevation. This may expose the species to other large carnivores in the habitat but honey badger activity pattern peaked at midnight retaining minimum temporal overlap with other large carnivores (e.g., tiger Panthera tigris, leopard Panthera pardus, and dhole Cuon alpinus) and moderate overlap with small carnivores (e.g., jungle cat Felis chaus, rusty-spotted cat Prionailurus rubiginosus). These behaviors, in turn, may facilitate the coexistence of species at such high density even with high carnivore density. We hope the findings of this study will fill the existing knowledge gap of this species and aid in guiding the conservation of the species in other landscapes and reserves.

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Density-dependent habitat selection by juvenile Atlantic salmon (Salmo salar) in experimental riverine habitats

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f99-074 ◽

1999 ◽

Vol 56 (7) ◽

pp. 1298-1306 ◽

Cited By ~ 25

Author(s):

Tammo P Bult ◽

Stephen C Riley ◽

Richard L Haedrich ◽

R John Gibson ◽

Jan Heggenes

Keyword(s):

Habitat Selection ◽

Population Density ◽

Atlantic Salmon ◽

Habitat Use ◽

Salmo Salar ◽

Implicit Assumption ◽

Experimental Conditions ◽

Density Dependent ◽

Atlantic Salmon Salmo Salar ◽

Juvenile Atlantic Salmon

We investigated habitat use of Atlantic salmon (Salmo salar) parr in experimental riverine enclosures made up of pool, riffle, and run habitats over a range of densities (0.1-1.25 fish·m-2) to test the implicit assumption in habitat modelling that habitat selection does not change with population density. Results indicated that habitat use changed with population density, with relatively more parr in pools and fewer in runs at higher population densities. Temperature influenced parr distribution, with relatively more parr in runs and fewer in riffles and pools at higher temperatures. Parr distribution was primarily affected by hydromorphological differences among pool, riffle, and run habitats. Effects of population density and temperature on use of pool, riffle, and run habitats were often as large as effects of hydromorphological differences among pool, riffle, and run habitats on fish distributions over the range of temperatures and densities observed. Results varied considerably, despite controlled experimental conditions. We concluded that habitat selection by juvenile Atlantic salmon parr may be density dependent and potentially quite variable.

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Mountain beaver home ranges, habitat use, and population dynamics in Washington

Canadian Journal of Zoology ◽

10.1139/z07-007 ◽

2007 ◽

Vol 85 (3) ◽

pp. 328-337 ◽

Cited By ~ 19

Author(s):

W.M. Arjo ◽

R.E. Huenefeld ◽

D.L. Nolte

Keyword(s):

Population Density ◽

Habitat Use ◽

Woody Debris ◽

Habitat Characteristics ◽

Home Ranges ◽

Limited Information ◽

Managed Forest ◽

Forest Sites ◽

Mountain Beaver ◽

Aplodontia Rufa

The mountain beaver ( Aplodontia rufa (Rafinesque, 1817)), endemic to western North America, is the only extant member of the family Aplodontidae. Limited information on movements and habitat use throughout the species’ range is available. We radio-collared 41 mountain beavers to determine home ranges, dispersal, habitat use, and population densities on two managed forest sites in coastal Washington. Both sites were recently harvested for timber. The Donovan site (16.6 ha) was treated with herbicide before seedling planting and the Sylvia site (8.9 ha) was not treated. Mountain beaver home ranges (Donovan: 4.18 ± 0.81 ha; Sylvia: 1.39 ± 0.4 ha) were greater than previously reported in the literature (0.02–0.2 ha). Home ranges (P = 0.009) and core use areas (P = 0.05) on the herbicide-treated Donovan site were larger than those observed on the untreated Sylvia site. Mountain beaver population density declined from 2002 (n = 16) to 2003 (n = 8) on the Donovan site, and reinvasion onto the site after removal trapping was low (n = 7). Population density more than doubled on the Sylvia site from 2002 (n = 21) to 2003 (n = 55), and reinvasion was greater (n = 27) than observed at Donovan. In addition, we documented habitat characteristics centered at 9 Donovan and 10 Sylvia nest locations. Sites were similar in most habitat characteristics, but the Sylvia site had more herbaceous forbs, stumps, and woody debris. Our findings suggest that mountain beaver populations and home ranges are affected by availability of forage, such as herbaceous forbs, after herbicide treatment, as well as by availability of woody cover.

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