When I began writing this article my intent was to create an informative document explaining the differences between Rio Grande wild turkeys (Meleagris gallopavo intermedis) and Eastern wild turkeys (Meleagris gallopavo silvestris), with respect to their unique histories, biology, and the hunting regulations associated with each subspecies.  Writing such an article was the request of Texas Hunting and Fish Network community developer Brett Valdez, who suggested I write it as a timely precursor to the up and coming spring turkey season.  Sorry Brett I got a little off-course.  Here I sit putting the finishing touches on what started as a simple informative paper but ended up an exploration of a gap in our knowledge of wild turkey biology.  This exploration is on going and has in no way resulted in any definitive conclusions, but has uncovered the need for research that could improve our understanding of wild turkey management.

Rio Grande (left) and Eastern Wild Turkey (right)

While chronicling the history of Texas wild turkey populations I noticed two facts that seemed to contradict each other.  One was the apparent inability of biologist to reestablish East Texas turkey populations by capturing and releasing Rio Grande wild turkeys into the East Texas forest which was historically occupied by Eastern wild turkeys.  Many attempts at this have failed and off the top of my head I wasn’t sure why.  A question a little research should answer, right?  Wrong.  After many days of intense research and exhausting all my resources the most definitive answer concearning this query I could find was that rainfall was the limiting factor in Rio Grande wild turkey distribution.  This seems like a logical conclusion, except when compared to the well established trend of substantial growth among Rio Grande wild turkey populations in central Texas during years of above average rainfall.  Alone this trend also makes perfect sense, but when considered along side the failure of released Rio Grandes to establish populations in East Texas where there is comparatively always above average rainfall, it prompts further investigation.  The remainder of these writings describe the history of the two primary subspecies of wild turkey in Texas, and then diverge into the exploration of the query described above, and state a few of the many hypothesizes I have formulated over the past couple of months while investigating possible explanations for the distinct boundaries of wild turkey subspecies distribution.

Historically, Eastern wild turkeys occupied 30 million acres in East Texas, ranging from the coastal prairies to the Red River, remaining east of the Trinity River.  Their population thrived in this area until the early 1900s when commercial hunting and changing landscapes drove the birds to the brink of extinction, leaving no viable Eastern turkey presence in the piney woods of East Texas.  As public concern for diminishing turkey populations grew, legislation was eventually passed that protected remaining birds, but did little for turkey numbers in East Texas where there was nothing left to protect.  The first restocking efforts involved releasing pen-raised Eastern wild turkeys that were not acclimated to the wild and subsequently had no chance of surviving long enough to reestablish a turkey population in the piney woods.  Later attempts involved releasing wild Rio Grande turkeys, wild Meriam turkeys, and genetic hybrids of the two that were sometimes cross bred with pen-raised Eastern turkeys.  These later attempts at reestablishment proved to be as futile as the previous attempts.  It wasn’t until pure wild Eastern turkeys were trapped and then relocated in East Texas that the region’s turkey population began to make a comeback.  What early 20th century biologists found out the hard way was that different subspecies of wild tukeys exist in very specific habitats, and are not able to adapt to habitats traditionally occupied by other turkey subspecies.  Rio Grande turkeys inhabit the south central portion of the country occupying most of Texas, Oklahoma, Kansas, and Colorado. Meriam turkeys are sparsely populated in West Texas and a few other dry mountainous regions of the United States.  The Florida Wild Turkey or Osceola wild turkey inhabits the panhandle of Florida.  All of these areas offer unique habitats that history has shown will support only the subspecies of turkey naturally occurring in those regions.  In the East Texas piney woods Eastern wild turkeys made an inspiring come back and are by far the most common sub species of wild turkey found in the United States today occupying the entire Eastern half of the country.  In Texas the western limit of their range is associated with areas receiving 36in of average annual rainfall.

By John Schwarzlose of Texas Wildlife Unlimited

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