Cow Elk Survival Research Update

Between 2005 and 2008, Idaho Fish and Game biologists and volunteers fitted 673 adult cow elk with radio collars in 11 elk management zones across the state. They have been tracking the animals to monitor their survival. To date, overall survival among the collared elk has been within normal ranges, except in two study areas. The causes of death have come from a variety of sources. Data regarding cause specific mortality is presented in the table below.

Summary:

1. Four zones have above 85 percent or better survival, with harvest the primary cause of mortality, and low to high wolf density.
2. Three zones have 83 to 87 percent survival, with predation the primary cause of mortality, and high wolf density.
3. Two zones have below 82 percent survival, with wolf predation the primary cause of mortality, but one has high wolf density and one very high density.

 Notes For Table 

Cow elk population status refers to state management objectives. Survival rates are based on adult female elk radio-collared and monitored over several years.

Wolf density refers to the relative number of wolves within a certain zone, (low, medium, high and very high) based on estimated numbers in December 2007.

Adult Cow Elk Survival Data
Study Zone (# of radio-collared cow elk)	Cow Elk Population Status	Annual Survival	Annual Mortality	Wolf Density
Weiser (44) 2005-08	above objective	89%	hunting – 8% wolves – 1%	medium
Tex Creek (57) 2006-08	within objective	89%	hunting – 8% cougar – 1%	low
Pioneer (79) 2005-08	within objective	88%	hunting – 6% cougar – 3% wolves – 1%	medium
McCall (25) 2005-07	within objective	81%	hunting – 6%	high
Boise River (40) 2005-08	within objective	85%	hunting – 5% predation – 4%	high
Island Park (41) 2005-08	below objective	80%	hunting – 17% cougar – 1%	medium
Elk City (30) 2005-07	within objective	87%	wolves – 5% cougar – 5%	very high
Salmon (116) 2005-08	within objective	83%	cougar – 6% hunting – 5% wolves – 2%	very high
Sawtooth (88) 2006-08	within objective	87%	wolves – 4% hunting – 3% cougar – 2%	very high
Smokey Mountain (37) 2005-08	below objective	81%	wolves – 5% cougar – 4% hunting – 3%	high
Lolo (116) 2005-08	below objective	75%	wolves – 20% cougar – 3%	very high

Lolo Zone in Detail
Notes: Objective 6,100 to 9,100 female elk - latest count in 2006 of 3,254, well below objective. Calf statistics are based on a total of 60 calves radio-collared in 2005 and 2006.
Population	Annual Survival	Annual Mortality
Cow Elk 2005-08	75%	wolves – 20% cougar – 3%
Elk Calf 2005-06 December to June	73%	wolves – 18% cougar – 7%