Sunday, October 14, 2012

In Effigy

I was pleased to see the fall issue of Human–Wildlife Interactions (a peer-reviewed journal focused on human/wildlife conflicts, published by the Jack Berryman Institute of the University of Utah) included a paper by our local USDA Wildlife Services Supervisor Rod Merrell. Rod’s paper outlined some successful methods to mitigate conflicts with ravens in industrial areas.

Here’s a picture of Rod setting a snare for a bear that was killing our sheep a few years ago.
Common ravens are federally protected under the Migratory Bird Treaty Act, so when ravens cause problems, solutions generally involve federal wildlife officials. As an ag producer, I’ve had to call on Rod for help with ravens on my lambing grounds, but industrial companies have unique challenges when it comes to ravens at their facilities (including coal and trona mines, gas facilities, and power plants) since shooting, harassment and destruction of nests are not allowed without a special permit from the U.S. Fish & Wildlife Service.

Nesting ravens can be very aggressive towards workers coming near their nests, which can be built on catwalks, stairwells, derricks and smoke stacks, but most raven complaints at industrial facilities involve roosting ravens. While a few ravens aren’t often much of an issue, Rod is called to respond to cases involving 150-300 roosting birds and the health and safety issues caused by their fecal material deposited on equipment, handrails, stairs, and other surfaces that workers routinely contact.

Rod’s excellent five-page paper only discusses methods he has personally used to mitigate raven conflicts, from the use of lasers, hazing, scarecrows, sirens, propane cannons, avicides, shooting, and –my favorite– effigies. The paper acknowledges that ravens are intelligent birds with remarkable eyesight, and an acute sense of smell.

Rod reports, “Based on my experience, effigies are the most effective means to keep ravens from roosting on towers, tanks, cable trays, and other elevated structures.” After experimenting with a variety of effigies (including fake ravens used as movie props, which were quickly “torn to pieces” by ravens), Rod recommends the use of actual dead ravens, hung upside down where the wind will create some movement. His paper goes into specifics about the placement of effigies (and how they must be properly disposed of according to federal permit guidelines when no longer needed), but I won’t go into detail here.

Rod also acknowledges that breaking up a roost is a process, “often time- consuming, frustrating, and requiring follow-up,” and no single technique will resolve the problem.

“One must reinforce danger with other tools and techniques or the ravens will habituate to the natural effigies with time,” he wrote.

But what I love about this paper is the endorsement of the value of effigies – a practice used by traditional agrarians around the globe. Sometimes ancient methods are proven to be the most effective. I would include the use of effigies, livestock guardian dogs, and spiked collars as ancient tools that are still proven in value today.

Here’s a scene from rural Turkey in October 2010. Turkish guardian dogs tethered, with a dead wild boar, chickens scratching nearby, and an effigy of a Eurasian Magpie hanging from a piece of farm equipment.

Steve provided these shots from our late friend Aralbai's place in Mongolia. These images were taken during Steve's first hunts with Aralbai in 1997 (adventures that involved fox, feasts & drinking). The scare magpie hung adjacent to Aralbai's corrals during the lambing season.


Chas Clifton said...

Is "effigy" the right word if it is a real deal bird, as that magpie appears to be?

Cat Urbigkit said...

Chas, you're probably right, but you'll notice we use the words "scare magpie" when pointing to the real dead bird in Steve's images.

CZLion said...

Growing up in NE Iowa we had huge elm trees lining our boulevard which, during the Fall, were filled with thousands of starlings nightly. The noise and crap smell was horrendous. My father had read where placing dead starlings in the trees would drive them away. The police gave us permission to shoot the birds which we did, tied them to string and flung them into the trees. It didn't work. Riding a bike dragging a snow shovel on the street helped.

Cat Urbigkit said...

You got a great story out of it anyway!

Anonymous said...

"The paper acknowledges that ravens are intelligent birds with remarkable eyesight, and an acute sense of smell."

That is surprising to me. Most birds have a quite poor sense of smell.

Steve Bodio said...

That was the conventional wisdom, but more and more birds are proving to smell well. New World vultures first, but also various seabirds, waterfowl, and pigeons as well as Corvids are now being reconsidered.

Moro Rogers said...

Turkey smells pretty good.=p