11.10.2008

Where shrikes lived before barbed wire

This past weekend a group of volunteers from across Georgia came together to work with DNR biologists and managers to participate in collecting native grass seeds to redistribute in areas where the native vegetation has been replaced by exotic, invasive plants. Restoration efforts, likes the one this weekend at Panola Mountain State Park and Sprewell Bluff State Park, epitomize the type of conservation efforts that are so desperately needed if we wish to conserve the biodiversity our state has been blessed with. This is where the real work gets done. Not in the ivory towers of academia, not behind a desk, but out in the field. Well... I take that back, (even though all of us would like to spend all our time in the great outdoors.) If not for the work of researchers and planners, the on-the-ground work would never materialize. (Being a grad student, I should know better than to criticize the ivory towers I spend my typical day in, but that is neither here nor there.)

When I was growing up, trees were trees, grass was grass, birds were birds, etc. I had an appreciation of the wild things around me, but I had no idea of the historical landscape of our state. I did not know which species were native versus which were exotic. The only exotic, invasive species I remember anyone talking about when I was growing up was Kudzu, but I always thought it looked kind of neat. So it came as a big shock in my undergrad schooling, to learn that most of our native warm-season grasses were being out competed by exotic cool-season grasses. I was amazed to learn that Georgia's ecosystems were largely fire-dependent, and that years of fire suppression and development have severely reduced and fragmented our native landscape. As the habitat diminished, so did the species who called these places home.

The loss of native grasslands in Georgia has largely gone unnoticed, but it is an ecosystem that is vital to a myriad of species which forms the trophic base for the surrounding ecosystems. The abundant plant diversity gives rise to abundant invertebrate, rodent, and avian diversity , which, in turn, facilitates herpetafauna and carnivore diversity, and so on. But these places are almost gone. While habitat loss is the easily recognized culprit, fire suppression is just as guilty. As the landscape goes through succession, certain grasses get crowded out, some grasses remain, and pine forests emerge. If fire suppression continues, hardwoods will eventually out compete the pines. As the canopy closes up, the remaining grasses go away. While big, beautiful hardwood forests are valuable, so are all the other stages of forest succession; stages which are maintained by fire. Entire communities have evolved within this framework.

It took a long time to destroy this habitat and it will take a long time restore it. Additionally, it will take some pretty drastic measures bring it back. Woody vegetation is removed manually and by herbicides. Exotic grass is just about impossible to control manually, so more chemicals are used combined with a prescription of fire. The ground becomes scorched, but out of the ashes, and on top of the bare mineral soil, native grass arises. Long lost habitat is restored.

A lot of people ask me where did Loggerhead Shrikes live before pastureland and barbed wire fences. This is the answer.
















My dad collecting yellow Indian grass (Sorghastrum nutans) at Panola Mountain State Park



Longleaf pine (Pinus palustus) habitat where we collected seeds at Sprewell Bluff State Park



At Sprewell Bluff State Park the fall colors were phenomenal as is exemplified by this tulip poplar (Liriodendron tulipifera)

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