Not every animal, either adult or juvenile, lives for ever; hard concept for many people to appreciate Carrying Capacity – ability of the habitat and distribution of resources to support a certain population level Harvest/Removal management strategies – – What is the population goal? Social and/or ecological carrying capacity – Where is the population in relation to the goal or population objective? – What rate of removal will meet the goal?

– Monitor the population response to removal – Compensatory vs. Additive Mortality – Density Dependent Reproduction – Make annual adjustments to removal rates Run through real examples of current elk, pronghorn, and bighorn herds

Elk Herds

Pronghorn Herds

Bighorn Herds

River Mountains - Desert Bighorn Sheep – 1986 – 240 population estimate – From 1986 – 2010 removed 436 bighorn – 2011 – 250 population estimate Mt Jefferson – Desert Bighorn Sheep – 2003 – 290 population estimate – From 2003 – 2008 removed 116 bighorn – 2010 – 280 population estimate

Compensatory Mortality Compensatory Mortality – improved survival of remaining animals not harvested or they are “compensating” for the loss of animals to harvest Additive Mortality – no improvement in survival of animals that were not harvested, therefore loss of harvested animals is in “addition” to animals that die to nonharvest mortality factors

Female Pronghorn Age Classes One does Aug Harvest Wounding Loss Nonhunting Mortality survived to Feb Nonhunting Mortality Aug 2006

Female Pronghorn Age Classes One does Aug Nonhunting Mortality Survived to Feb Nonhunting Mortality Aug 2006 Same Unit 067, 068 Pronghorn Herd without Harvest Aug 2006 Age Class #s with Harvest and Compensatory Mortality

Statewide Pronghorn estimate for 2011 was 27,000. Several pronghorn herds statewide are at or approaching their current carrying capacity. Other herds are one catastrophic fire away from losing a significant proportion of their habitat. Almost 1,300 doe (horns shorter than ears) tag applicants in 2011; 5 to 1 draw odds; tremendous demand from hunters. By applying a 3-5% harvest rate to the doe segment of these herds, we can better manage herds to their habitat, reduce major declines when catastrophic events occur and provide substantial hunting opportunities where expressed demand exists.