Darn coyotes...

[Oak]

The new Wildlife Monographs:

Demographic response of mule deer to experimental reduction of coyotes and mountain lions in southeastern Idaho

http://onlinelibrary.wiley.com/doi/10.1002/wmon.4/abstract

Abstract

Manipulating predator populations is often posed as a solution to depressed ungulate populations. However, predator–prey dynamics are complex and the effect on prey populations is often an interaction of predator life history, climate, prey density, and habitat quality. The effect of predator removal on ungulate and, more specifically, mule deer (Odocoileus hemionus) populations has not been adequately investigated at a management scale. We tested the efficacy of removing coyotes (Canis latrans) and mountain lions (Puma concolor) for increasing survival and population growth rate of mule deer in southeastern Idaho, USA, during 1997–2003. We assigned 8 game management units (GMUs) to treatments under a 2 × 2 factorial design (treatments of coyote removal and lion removal) with 2 replicates of each treatment or reference area combination. We used methods typically available to wildlife managers to achieve predator removals and a combination of extensive and intensive monitoring in these 8 GMUs to test the hypothesis that predator removal increased vital rates and population growth rate of mule deer. We determined effects of predator removal on survival and causes of mortality in 2 intensive study sites, one with coyote and mountain lion removal and one without. We also considered the effects of other variables on survival including lagomorph abundance and climatic conditions. In these 2 intensive study areas, we monitored with radiotelemetry 250 neonates, 284 6-month-old fawns, and 521 adult females. At the extensive scale, we monitored mule deer population trend and December fawn ratios with helicopter surveys. Coyote removal decreased neonate mortality only when deer were apparently needed as alternate prey, thus removal was more effective when lagomorph populations were reduced. The best mortality model of mule deer captured at 6 months of age included summer precipitation, winter precipitation, fawn mass, and mountain lion removal. Over-winter mortality of adult female mule deer decreased with removal of mountain lions. Precipitation variables were included in most competing mortality models for all age classes of mule deer. Mountain lion removal increased fawn ratios and our models predicted fawn ratios would increase 6% at average removal rates (3.53/1,000 km2) and 27% at maximum removal rates (14.18/1,000 km2). Across our extensive set of 8 GMUs, coyote removal had no effect on December fawn ratios. We also detected no strong effect of coyote or mountain lion removal alone on mule deer population trend; the best population-growth-rate model included previous year's mountain lion removal and winter severity, yet explained only 27% of the variance in population growth rate. Winter severity in the current and previous winter was the most important influence on mule deer population growth. The lack of response in fawn ratio or mule deer abundance to coyote reduction at this extensive (landscape) scale suggests that decreased neonate mortality due to coyote removal is partially compensatory. Annual removal of coyotes was not an effective method to increase mule deer populations in Idaho because coyote removal increased radiocollared neonate fawn survival only under particular combinations of prey densities and weather conditions, and the increase did not result in population growth. Coyote-removal programs targeted in areas where mortality of mule deer fawns is known to be additive and coyote-removal conditions are successful may influence mule deer population vital rates but likely will not change direction of population trend. Although mountain lion removal increased mule-deer survival and fawn ratios, we were unable to demonstrate significant changes in population trend with mountain lion removal. In conclusion, benefits of predator removal appear to be marginal and short term in southeastern Idaho and likely will not appreciably change long-term dynamics of mule deer populations in the intermountain west. © 2011 The Wildlife Society.

 

[Ben Lamb]

In conclusion, benefits of predator removal appear to be marginal and short term in southeastern Idaho and likely will not appreciably change long-term dynamics of mule deer populations in the intermountain west. © 2011 The Wildlife Society.

i.e. - it's the habitat, stupid.
I spent 5 years on the WY Animal Damage Management Board trying to convince people of that. Didn't make a dent.

 

[Oak]

i.e. - it's the habitat, stupid.

That is SO funny. I almost made that my new signature line about 5 minutes ago.

 

[Ben Lamb]

http://www.newwest.net/topic/article/when_it_comes_to_wolves_its_the_habitat_stupid/C41/L41/

 

[rhomas]

I have no knowledge of what goes on out West, but here in the Southeast, and particularly here in SC, coyotes, coydogs, and wild dogs are the number one deer predator, and are destroying deer populations in the upper part of the state, as well as areas that have limited access to hunting. A study by the SC DNR, and the Savannah River Site ( the plant where U-235 for weapons is extracted, and the repository for over half of the nation's nuclear waste), has shown the 'yote predation has depleted almost 10% of the deer population of just 5 years ago. It is also predicted that this depredation will continue to rise at alarming rates every year, until the deer herd is decimated. Of course, no predator hunting is allowed on the site, which common sense would seem to indicate contributes to the problem. Unfortunately DNR is using the study conducted on the site as the basis for wanting to institute a tag system for deer in SC, which would also establish a 4 deer per year limit in the parts of the state where we have never had a limit of any type. This study was sponsored and funded in large part by out of state hunters, and hunters from the upper part of SC who have always had a limit, along with baiting and hound hunting restrictions. The other side of the coin is that the Insurance Institute of SC has determined that the deer population in the lower part of the state is at an all time high, in spite of the increased coyote predation. DNR now allows us to hunt 'yotes, coydogs, and hogs 24/7-365, but only with rimfire cartridges at night.

I have killed more 'yotes and coydogs in the last year and a half, than I had previously killed since the 'yotes first appeared in SC after hurricane Hugo. I killed 5 last year, with 3 of them running one of our club's beagles. The 'yotes were in a pack of at least a dozen and if I hadn't killed those three, that beagle was about to become their next meal.

I believe that the full impact of this invasive species, if left unhunted would eventually destroy our deer herds, but with more and more hunters getting involved in varmint hunting as well as killing 'yotes and coydogs while hunting deer, turkey, and birds, hopefully we can at least keep them in check and balance the odds in favor of the deer and other game.

 

[Ben Lamb]

we can send y'all some woofs if you want. They're hell on coyotes.

Shoot every coydog you see.

 

[1_pointer]

IIRC they have red woofs it not yet, they aren't that far away...

Regarding habitat, a professor at Utah St. had two graphs that he like to show. One showed the acres of federal land that had vegetation treatments by year and the other showed the mule deer populations by year. I found it very interesting, especially considering that chaining was the most common treatment method during those times....