Awakening to the spirit and beauty of the northern Great Plains
Thursday, May 27, 2010
71,000 coyotes killed--what does this mean for birds?
Here is today's news report on the final tally of from the coyote slaughter:
"Coyote ugly: 71,000 killed in Sask cull
By The Canadian Press REGINA - A coyote bounty Saskatchewan offered hunters and farmers has resulted in more than 71,000 of the animals being killed.
Agriculture Minister Bob Bjornerud says the number is a surprise, but he's pleased with the results.
Bjornerud says the intention was not to eliminate coyotes, but to control the population because the animals were killing livestock and putting farm families in danger.
Jack Hextall, chairman of the Saskatchewan Cattlemen's Association, says attacks on livestock were costing producers thousands of dollars in losses.
The province paid $20 per coyote under a pilot program which ran from November until the end of March.
Bjornerud says the final cost for the program should be about $1.5 million."
Leaving aside the financial and political stupidity of a government spending $1.5 million to solve a problem that was "costing producers thousands of dollars," I am going to speculate on what losing 71,000 coyotes might do in the short term to grassland ecosystems that are already under a lot of stress from habitat destruction and conversion.
71,000 is a big number when we are talking about a top predator. In a post on January 15, I wrote about the effect of removing a lot of coyotes--particularly how it releases the Red Fox, a non-native predator, from any limits on its numbers. Though the fox is native to the continent it was not found on grasslands before settlement and agriculture. In the last century the Red Fox has had some periods where it has exploded in numbers, usually after a large loss of coyotes, which otherwise keep it in check. (See Finley J.K. 2006. The rise and fall of the Red Fox beneath the apex of Palliser’s Triangle. Blue Jay 64(3): 155 - 159 and Finley, J.K. 2005. The fox that stole the apex of Palliser’s Triangle: a correction. Blue Jay 63(3) : 135-138)
Grassland birds are not adapted to predators such as the Red Fox and Racoon so when these mammals increase bird populations suffer.
Here is an excerpt from a research paper about a declining grassland bird, the Greater Prairie Chicken, explaining how nest success in ground-nesting birds (ducks and the prairie chicken) is greater in areas with higher coyote populations. And wherever coyotes numbers are down and Red Fox numbers up, nest success is cut in half. The full paper is available on the National Prairie Wildlife Research Center's website
"Red foxes and skunks have been the most common mammalian predators of prairie-chicken nests throughout most of the eastern range. Foxes generally have more impact than skunks because they commonly prey on the nesting hen. Over a 10-yr period, Svedarsky (1988) found December fox fur prices to be positively correlated with spring booming-ground counts two springs later. The conclusion was that trapping effort increased with the market incentive and that other potential predators were trapped as well (skunks, feral cats [Felis domesticus]). If trapping (and hunting) did, in fact, reduce mammalian predator numbers, it should have resulted in higher prairie-chicken production the next year and higher booming-ground counts the following year. This appeared to be the case. Further evidence for the high impact of foxes on large ground-nesting birds is that in areas where coyotes tend to displace foxes, nest success often increases. In North Dakota and South Dakota, Sovada et al. (1995) studied comparable areas except that some areas were dominated by red foxes and others by coyotes. Duck nests in coyote-dominated areas experienced nearly twice (32%) the nesting success as those in fox-dominated areas (17%). The authors suggested that managing an area for coyotes rather than for foxes could be an effective method of increasing duck nest success. Svedarsky (1992) observed an increase in apparent nest success of larger ground-nesting birds (ducks and grouse) over a 2-yr period in Minnesota. As coyotes apparently displaced foxes, nest success increased from 8.3% of 12 nests to 61.3% of 31 nests."
The voices of coyotes are part of the twilight and morning song of the prairie--something we take for granted like the creek running in spring. Last weekend my wife Karen and I were remarking that we have heard very few coyotes calling this spring. Most nights now there are none to be heard. To be honest, at first I wasn't thinking it was the coyote slaughter. After all, the estimate was merely 21,000 or so--more or less the same as an average winter. 71,000 is a very different number, different enough to do some short term damage that contributes to the long term decline of prairie ecosystems.
Two weeks ago, I saw my first red fox on the land since we purchased it in 2005. It was in broad daylight. The next weekend I saw two foxes in the same spot, again running in the light of day.
Meanwhile, the surviving coyotes are nursing their litters right now. If you care for the wellbeing of this land, lift a prayer or thought in their direction, that they may prosper this summer and replace that lost 71,000 as soon as possible.