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April 20, 2001

By Dale Rollins
Extension Wildlife Specialist

A dark force in wildlife management...

"Bigger bugs have smaller bugs, upon their backs to bite 'em. Smaller bugs have lesser bugs, and so on infinitum."—The Parasitologist's Pledge

Back in January 1997, I traveled to Brenham at the request of the county agent to give a presentation to the Washington County Wildlife Management Association. Brenham isn't officially in my territory, but the agent knew I had some expertise in quail management that suited the assigned topic: how to restore the bobwhite to Washington County. At one time, Washington County boasted being the number one county for quail in Texas, I understand. But today a covey of bobwhites there is about as common as hen houses in West Texas.

So, what's caused the `quail decline' that seems to have ravaged most of east and central Texas, indeed the southeastern U.S.? And more importantly, can we do anything about it?

My first assessment about the quail decline in that region stemmed from the fact that "their fences were too close together." It's easier to manage quail (or just about any other species of wildlife) on larger parcels of land. As you drive from west Texas to east Texas, notice what happens to the distance between fences (i.e., pasture size). In wildlife lingo, we say the habitat suffers from "fragmentation."

When I hear the term "fragmentation," I think of a hand grenade. And, like a grenade, when the "pin is pulled," there are some drastic consequences. Fragmented habitats are small "islands" of habitat separated by "oceans" of less than ideal conditions.

For the golden-cheeked warbler, habitat fragmentation usually coincides with a high incidence of nest parasitism by cowbirds. For the bobwhite, it coincides with a high incidence of nest depredation by an assortment of mesomammals such as skunks and raccoons. If our land management works to the favor of our enemy[ies], then we should anticipate high casualty rates.

If fragmentation still sounds abstract, think of it in terms of ranching. What's happened to the average ranch size over the last 50 years? It's become more "fragmented" as larger estates are divvied into smaller ones, and smaller ones are subdivided into 5-acre ranchettes. Do you see that trend improving in the future? Neither do I. But what's that got to do with quail?

As the distance between fences decreases, grazing intensity almost invariably increases. Sure, there are lots of big places that are overgrazed, but the situation is compounded on 20-acre tracts. It may happen because the "rancher" wants to preserve an "ag use" tax valuation, or perhaps it's just ignorance about how many grazing animals can be supported. Whatever the motive, severe overgrazing is the result. As you drive up and down the I-35 corridor, pretend you're a quail hen looking for suitable nesting cover (i.e., basketball-sized clumps of bunchgrasses). Nervous proposition, eh?

Fragmentation comes in different forms. Land use changes can have profound effects. In Washington County, the small farms (and attendant weedy fence rows) have given way to coastal bermuda and brush hogs. A good strategy for mama cows perhaps, but not for mama quail.

Fragmentation can also occur on larger acreages if grazing intensity is too heavy. Data from recent research projects here at San Angelo suggest that quail nesting success is best when there are more than 300 suitable "nest clumps" per acre. How many would you find on your back 40? The greater availability of potential nest sites forces would-be nest predators to search a larger area, and therefore be less efficient at locating nests. You might say that there's safety in numbers.

So, if quail are my objective in Washington County, can I convert my tame pasture back to native rangelands in order to restore bobwhites? In other words, if I build it, will they come? Perhaps...but not necessarily. Think about it. If I wish to convert my 20-acre "ranch," I can plant species that quail use for nesting (primarily little bluestem) and may even entice a hen to build a nest there (assuming there's still breeding stock in the area). Now I have to hope she can incubate those 14 eggs for 23 days without some varmit finding her. If that 20-acre pasture offers the only nesting cover, reckon how long before her enemies (e.g., skunks) learn to focus their attention there? Not long. I figure the odds of hatching a successful nest under such conditions are perhaps one in 20, or worse.

Dr. Fred Guthery refers to such habitats as "cemetery habitats" inhabited by "zombie populations." The quail therein "are dead, they just don't know it." Such is the bobwhite's plight across most of the country east of I-35. One Florida biologist predicts that bobwhites will become extinct in the southeastern U.S. in 2005. When I first heard such a dire forecast back in 1992, I dismissed it as poppycock. I'm not laughing now.

In order to escape the cemetery habitat syndrome, we must manage a large enough acreage to overcome the gremlins that thrive on small acreages. Or, we must assemble enough contiguous landowners with an interest in quail management to biologically affect nesting conditions over a broader landscape. We must focus on increasing quantity of nesting cover, not just the quality, if we are to foil the quail hen's adversaries. We've been effective with deer management under such cooperative approaches, so maybe there's hope for quail. I hope so.

Speaking of deer, one of the most visible tracks of fragmentation is the increasing number of "deer-proof" high fences. I've heard estimates that some 4 million acres are behind high fences, but it could be twice that. The rate at which new high fences are appearing is like an irregularly shaped mole on the back of one's leg—cause for concern about what it's going to look like a few years down the road. Wildlife professionals are having increasing heartburn over the high fence issue and where it's headed.

The fragmentation issue is one that bodes ill for both ranching and wildlife. It's in the best interest of both to keep land management units at a sufficient scale of ownership to remain viable, both economically and biologically. To keep bobwhites from becoming endangered, we have to keep ranchers from becoming endangered. Neither is a given any more.