Wyoming Range Mule Deer Project


The Wyoming Range Mule Deer project is focused on understanding various aspects of mule deer ecology to inform on-the-ground management and policy regarding Wyoming Range mule deer, as well as answer foundational questions in wildlife ecology. Our work primarily centers on tracking mule deer throughout their lives, while assessing their nutritional condition, movement, habitat use, and survival, among other elements. Through these efforts, we are uncovering previously unknown aspects of mule deer behavior, life history, and population dynamics that have direct implications for the conservation of mule deer in the Wyoming Range and beyond.

Our hypothesis:

Everything matters in nutritional ecology...

WRMD_ConcFig

What's the issue?

Winters in the Wyoming Range can be extremely harsh, which can cause dramatic dips in over-winter survival. Climate change has resulted in increasingly variable weather around the world with extreme conditions occurring more frequently, and animals must find a way to survive that change.

How're we tackling it?

Through long-term monitoring of individual mule deer in the Wyoming Range since 2013, we are assessing what factors influence survival of GPS-collared mule deer in harsh conditions, how fat levels during different seasons affect survival and reproduction, and the long-term effects of winter on animals. To get these data, we recapture the same GPS-collared individuals every autumn and spring and use ultrasonography to monitor changes in fat levels and pregnancy rates relative to habitat conditions. Evert animal that dies in the winter is retrieved and necropsied (i.e., biopsied) to determine the cause of death.

What are our findings?

From 2013 to 2019, the Wyoming Range mule deer herd experienced two incredibly severe winters, with adult survival dropping to around 65%. Our ongoing research is working to better identify how animals survive harsh conditions, and identify the potential long-term consequences that harsh winters might have for both individuals and populations.

Why is it important?

Understanding how animals respond to changing environments and how they cope with increasingly severe weather conditions has important implications for population persistence.

What's the issue?

Energy development has increased in Wyoming over the last two decades, and much of this development has occurred on winter ranges for migratory mule deer. Although population declines often follow development of winter ranges, the pathways by which human disturbance prompts population declines is rarely revealed.

How're we tackling it?

We connected animal behavior with use of available food relative to it’s proximity to energy development by:

  1. Using GPS-collar data from mule deer to evaluate avoidance of energy development.
  2. Collecting on-the-ground data on how much of available food (i.e., sagebrush) deer were eating near and away from energy development.

What are our findings?

We found that deer avoided energy development at multiple scales and this left untapped food near development. This avoidance resulted in an additional loss of viable habitat that was 4.6 times greater then habitat lost directly to development.

Why is it important?

Quantifying the losses in food associated with energy development can give managers and planners a better understanding of what can be expected for mule deer populations where future development is being proposed.

What's the issue?

How're we tackling it?

What are our findings?

Why is it important?

What's the issue?

How're we tackling it?

What are our findings?

Why is it important?

What's the issue?

How're we tackling it?

What are our findings?

Why is it important?

What's the issue?

How're we tackling it?

What are our findings?

Why is it important?

What's the issue?

How're we tackling it?

What are our findings?

Why is it important?

What's the issue?

How're we tackling it?

What are our findings?

Why is it important?

People working on the project:

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Funders

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Publications

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Project updates

  • Project PDF download here