Behavioral and Demographic Responses of Mule Deer to Energy Development on Winter Range

Context Wildfire and vegetation treatments affect mule deer (Odocoileus hemionus) populations across the western United States. However, the relative influence of fire and treatments on habitat use by mule deer in Arizona is not well defined. Aims We examined locations of mule deer on the Kaibab Plateau in northern Arizona, so as to determine the influence of vegetation treatments and wildfire severity on deer habitat-use patterns across their winter range where fires and treatments had occurred previously. Methods We used locations (n = 11297) from 21 adult female mule deer fitted with global positioning system collars to model probability of use as a function of habitat covariates. Key results The best model describing winter-range habitat use by mule deer on the Kaibab Plateau included covariates describing the age of vegetation treatments and fire severity. Increased deer use in winter was associated with areas of lower terrain ruggedness and reduced snow depths. Deer use also increased in areas that experienced a higher average fire severity, resulting in decreased vegetation heights. Among treatment age classes, deer use was greatest in areas containing vegetation treatments that were ≤6 years old, but negatively associated with treatments that were >6 years old. Conclusions Vegetation treatments designed to remove or reduce less palatable tree and shrub species to improve forage conditions may increase the use of winter habitats by deer on the Kaibab Plateau. Similarly, prescribed fire and rangeland treatments designed to return areas to a more natural fire regime and, thereby, generate new plant growth, may improve winter-range habitat conditions for mule deer. Implications Similar treatment strategies may also benefit mule deer populations throughout the western USA, by improving forage conditions on critical habitats and reducing the potential for catastrophic wildfire.

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Gastropod intermediate hosts of lungworms (Nematoda: Protostrongylidae) on a bighorn sheep winter range: aspects of transmission

Canadian Journal of Zoology ◽

10.1139/z90-278 ◽

1990 ◽

Vol 68 (9) ◽

pp. 1976-1982 ◽

Cited By ~ 3

Author(s):

L. A. Robb ◽

W. M. Samuel

Keyword(s):

Mule Deer ◽

Bighorn Sheep ◽

Ovis Canadensis ◽

Intermediate Hosts ◽

Gastropod Species ◽

Winter Range ◽

Infective Larvae ◽

Third Stage ◽

Inherent Problem

A study of the gastropod intermediate hosts of the lungworms Protostrongylus stilesi and Protostrongylus rushi was conducted on a bighorn sheep (Ovis canadensis canadensis) winter range in southwestern Alberta, 1984–1985. Over 7000 gastropods were examined. Seven gastropod species were infected with Protostrongylus-type larvae: the predominant intermediate hosts were Euconulus fulvus (6.8% infected), Vertigo gouldi (5.6%), and Vertigo modesta (3.2%). Prevalence of third-stage (infective) larvae was highest in September and April, coinciding with use of the winter range by bighorn sheep. An index of lungworm availability to sheep was highest in autumn in the margins of aspen copses and in spring in the grassy openings. Copses were used extensively by sheep in autumn, and open areas were used in the spring. Presence of a mule deer (Odocoileus h. hemionus) lungworm, Orthostrongylus macrotis, was an inherent problem.

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Noninvasive genetic surveys before and after a megafire detect displacement of migratory mule deer

10.1101/2021.05.21.445205 ◽

2021 ◽

Author(s):

Jennifer L Brazeal ◽

Rahel Sollmann ◽

Benjamin N Sacks

Keyword(s):

Fire Suppression ◽

Mule Deer ◽

Burned Area ◽

Winter Range ◽

High Severity ◽

Western Us ◽

Before And After ◽

Summer Range ◽

Capture Recapture ◽

Carry Over

Due to climate change and past logging and fire suppression, the western US are experiencing increasingly large and frequent wildfires. Understanding how wildlife respond to these mega-fires is becoming increasingly relevant to protect and manage these populations. However, the lack of predictability inherent in such events makes studies difficult to plan. We took advantage of a large high-severity wildfire that burned adjacent to an ongoing study of mule deer (Odocoileus hemionus) on their summer range upslope of the fire to investigate their displacement onto our study area both immediately and upon their return to summer range the following year. We used spatial capture-recapture models in conjunction with noninvasive fecal DNA sampling to estimate density and non-spatial Pradel robust-design models to estimate apparent survival and recruitment rates. Compared to density before the fire, we observed an increase in deer density and an increase in per-capita recruitment rates one month after the fire. These findings suggest that the immediate response of at least some deer was to flee the fire upslope onto the study area rather than to downslope toward their winter range. These changes did not carry over into the following year, however, suggesting that deer formerly using the burned area as summer range may have returned there despite the high severity of the fire, or may have chosen new areas for their summer range. This suggests that, at least in the short term, the fire did not negatively affect the deer population.

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