What To Do Wednesday: Issue #7

What to do about dangerous, wildlife “unfriendly” fencing.

Spring is the time of year that people typically associate with “home improvement,” whether it be cleaning out their house, sprucing up their yards, or working on various other construction projects. This also makes it a good time of year to assess your property, and identify potential hazards and risks for wildlife. Fences are just one such hazard, but they can be a significant one if not maintained or properly built in the first place. This week, we’re taking a look at wildlife friendly fencing, and how and why you should build your fence with animals big and small in mind.

Why have “wildlife friendly” fences? 

Fences are typically erected to keep animals in or out of an area. They are  highly effective in accomplishing this task, and as a result, fences are widely used to control the movement of livestock. Unfortunately, they also have the side effect of controlling and restricting the movement of wild animals.

When wildlife need to get past a fence, they will resort to jumping over it, sliding under it, or walking miles to find a location in which they can bypass it. Birds often do not see fences, flying straight into them. The result? Unnecessary energy expenditure (especially significant in the winter or during migration), injury, and even death. Sage grouse, mule deer, trumpeter swans, elk, peregrine falcons, moose, bison, bald eagles, grizzly bears, prairie chickens, and pronghorn are just some of the victims of poorly maintained or poorly designed fencing. Considering a number of these are federally threatened and endangered species, there is obviously a need to rethink (or remove) fences.

How do you fence for wildlife?

There are a few concepts that ring true regardless of the species you are fencing for. These include:

• Make fences as visible as possible for birds with PVC or flagging (this has proven very successful in preventing trumpeter swan and sage grouse mortality).
• Bottom wires/posts should be at least 18″ above the ground to allow animals to pass under.
• Top wires/posts should be no more than 42″ off the ground so that larger mammals can clear them easily.
• If building a barbed wire fence, use smooth wire or rail for the top and bottom to prevent tangling.
• Place posts at 16.5′ intervals.
• Build fences on level ground. Fences on slopes dramatically increase the height a jumping animal must clear.
• Install gates, drop-downs, or other passages along migration corridors or in areas where wildlife concentrate.
• Consider a seasonal, flexible electric wire fence in areas where cattle and ungulates are likely to both be present.

Consider this a “primer” on wildlife friendly fencing. There is much more to it, no doubt, and we are by no means the experts on this subject matter. There are plenty more resources on the topic with more detail and discussion (see below for links).

Removing or replacing dangerous, obsolete fences

There are many wildlife conservation organizations throughout the West that advocate and work to remove dangerous, obsolete fences or modify older fences to make them wildlife friendly. Right in our neighborhood, the Jackson Hole Wildlife Foundation has removed well over 100 miles of old, barbed wire fencing (big props for this!). Groups like these often rely on support from volunteers, so there is a big opportunity to lend a helping hand to an organization in your area.

For more information about wildlife friendly fencing, check out:
http://fwp.mt.gov/fwpDoc.html?id=34461
http://www.wildlifefriendlyfencing.com/WFF/Friendly_Fencing.html
http://wgfd.wyo.gov/wtest/Departments/Wildlife/pdfs/BULLETIN_NO530001795.pdf