Late last winter, I was greeting visitors at the county Park I work at in far western Travis county. A gentleman drove up in a late model hatchback with out-of-state plates. I noticed a pair of binoculars and a new copy of a 'Texas Birds" book on his dash. "Good morning sir, have you been here before?" I cheerfully said to one the first visitors of the day. "Naw, just came to see that famous bird. Where can I find it?" I had to think for a minute, because spring migration hadn't started yet, and there was nothing really of special interest to see right now, as far as birds go. "Um, do you mean the Golden-Cheeked Warbler? I don't know if they've arrived yet", trying to sound a bit unsure as to not let him down. "Yeah, Yeah, that yella' wobbler! Where can I see it? he said enthusiastically, obviously not catching the hint. (sigh. oh well....) " Yes sir, just go to the far end of the parking lot. Take the bluff trail down a few hundred yards, take a left at the landing, follow the creek 'bout a quarter mile, then be on the lookout for a big stand of oaks on your right, creekside, and start looking", I replied with authority. After all, I was in uniform. (a uniform adorned with the likeness of a golden cheeked warbler nonetheless) "Thanks so much" he said earnestly, as if he had just received some top secret insider information. I shouted a "Good luck!" after him, knowing full well he was too early in the season. Was he a serious birder? Maybe. Was he a beginner birder? Definitely. But it didn't really matter. This fellow was going to have an adventure trying to spot one of the rarest songbirds in North America.
People travel far and wide to catch a glimpse of the Golden Cheeked Warbler, a beautiful, small, yellow songbird streaked with black, that arrives in the Hill Country of Texas in early to mid March. Texas can boast, amongst other things, of having more bird species than any other state in North America, nearly 600. The sheer size of the state, 275,416 square miles, contributes to this biological diversity. And many birds that are sighted in Texas occur nowhere else in the nation thus prompting bird watchers from around the world to 'flock' to see them. Not only do many warm weather species nest in the Lone Star State but north-bound ones also pass through on their long migration flight. Many of these birds just remain for the winter (like a lot of my friends it seems!) before heading back to cooler climes as the oppressive Texas heat takes hold. The birds of Texas change with the seasons.
So back to our little 'famous' bird....
Several things make the Golden Cheeked Warbler special. Of the 360 bird species that breed in Texas, the warbler is the only one to nest exclusively in central Texas, more specifically in stands of mixed old growth Ashe Juniper (known as cedar 'round here) and oak woodlands(live oak, red oak, shin oak and lacey oak) on the Edwards Plateau. This selective type of behavior labels our little warbler a 'habitat specialist'. (which sounds more like a wildlife biologist than a 'picky little bird') These forests MUST be mature because the female utilizes the long, stringy bark of the Ashe Juniper to weave her nest. And by mature I mean the ashe juniper needs to be at least 17 feet in height and the oaks over 20 feet. For whatever reason, the bark of young cedar is not suitable for the female warbler. After meticulously weaving this nest she will bind it with bits of spider webs and line it with fur, feathers or grasses she finds, to cushion the 3-4 speckled eggs she will lay.
If you haven't caught on yet, the habitat I'm describing sure sounds quite a bit like Rockmoor. Well Sherlock, you would be correct to assume that Rockmoor IS ideal habitat for this little yellow warbler. So if I asked, "Does anyone know what animal at Rockmoor has something in common with a Giant Panda? Anyone? (and it's not a raccoon) If you said, the Golden Cheeked Warbler, you would be correct! They are both listed on the "Endangered Species" list. To put that in perspective, they are lower on the list than say, the Mountain Gorilla which is listed as 'critically endangered'. But higher than the Polar Bear, which has only attained 'vulnerable' status. (sorry Frosty-but don't worry, if us humans keep running the show you'll be there soon enough)
So what is an Endangered Species? By definition, it is "a population of organisms which is at risk of becoming extinct because it is either few in numbers or threatened by changing environmental or predation parameters". If we consider the Mountain Gorilla, the Giant Panda, the Polar Bear and yes, the Golden Cheeked Warbler, we are mainly talking about loss of habitat. Period. These wonderful, amazing creatures are running outta' places to live. Quite simply.
Now, I can hear some of you , "but Sally, a warbler ain't no Panda Bear". Yeah, well if I lived in China, or Africa, or the North Pole, I would be putting in the good fight for those at risk animals. But I don't. I live in Central Texas. And 'my' endangered animal is the warbler. And it lives in my backyard. And I think that's really cool! Biological diversity is crucial to the balance of Nature. Living in a mono-culture of, say, cedar and coyotes only, is not good for anyone or anything. Note: It is estimated that 1 in every 8 bird species in the world is at risk of extinction.
And recent surveys have reported a loss of up to 45% of suitable habitat for our warbler over a 10 year period. That's a lotta' land!
The GCW (yeah, you guessed it, Golden Cheeked Warbler) needs at least 250 acres of continuous forest patch, amongst the appropriate woodland, to nest. This size of acreage is becoming less and less available, as land cleared for development is increasing. Habitat for this bird is rapidly being lost or altered in some way due to urban sprawl and poor land management practices. Ongoing fragmentation of the remaining available habitat also creates further problems by isolating certain populations and thus reducing the flow of genes amongst them. This can potentially create a loss of genetic diversity.
GCW's are doubly threatened as they are losing their tropical rainforest winter habitat as well. Warblers only stay in Texas for about three months (from March till about June-give or take) and then fly south to Mexico and Central America. The rainforests that they frequently spend their winter months in are rapidly vanishing due to development also.
In addition to all this habitat loss, the GCW has also to contend with the dreaded Brown Headed Cowbird. This particular bird is known as a 'parasite' bird. It lays its' eggs in the nests of other birds (uh...rude!) and then the unfortunate foster parents are faced with having to feed too many mouths. And, more importantly, the Cowbird eggs tend to hatch at a faster rate and as a result have a higher survival rate. Brown Headed Cowbirds, studies have shown, have impacted the mortality rates of GCW's quite negatively, as they seem to favor the nests of songbirds. Thus, when biologists are formulating a GCW habitat management plan for protection, the Brown Headed Cowbird is almost always considered. And by that I mean, there is also 'management' (i.e.-trap and dispose of) for the Cowbird. I've had experiences with setting up and managing cowbird traps every spring for the past few years. It is an unpleasant duty to undertake, but like feral hogs, a necessary one.
Listing this species as 'endangered' is not without controversy. Landowners may be restricted in certain aspects of development on their land if it is discovered that a pair of nesting warblers are residents. Just imagine, if a pair of Giant Pandas decided that your backyard was an awesome place to start a family. ('bear' with me here, haha) The authorities might not want you to add on that extra storage space behind the garage for fear you might frighten or stress them. Pandas might not like power tools. Or any loud noises. At the Park I work at, after March 1st we are forbidden to use any loud tools, chainsaws or machines, in or near, Golden Cheeked Warbler habitat. It's the law!
In fact, in 2006, Ft.Hood military training base, lost 119 days of live-fire trainings as a result of restrictions on access because of the endangered Golden Cheeked Warbler. How do you think that was received?
And since about 97% of the land in Texas is privately owned, chances are the warbler is going to find suitable habitat on someones property. Like ours. And not a bird friendly park or preserve.
The authorities and government agencies responsible for the bird's protection realize this dilemma and in turn have offered reasonable incentives for landowners to 'jump on board' and help in the conservation of the GCW. I happen to feel it is a blessing, and not a burden to be one of the few places in Texas, in North America...in the world! that this little bird chooses to call home for a little while. But I realize, some people don't share that opinion.
In early to mid March, the male warblers arrive first and establish a territory about 10 acres in area. Older males usually reclaim the previous year's site and immediately defend it with song, among other things such as chases and physical attacks. But it is this song, often described as a "bzzzz layzeee dayzeee" that marks the beginning of Spring for me. And because a warbler is only 4.5 inches tall and not easily spotted, their song is how I find them.
Rockmoor has a very, very healthy bird population. All sorts of summer and winter migrating avians pass through our juniper and oak woodlands. It truly is a birder's paradise. So if you happen to be visiting Rockmoor this Spring, bring along some binoculars and listen for the buzzing sound of the Golden Cheeked Warbler. And when you finally spot one, you'll be witnessing a very rare piece of natural history. Just one more thing that makes Rockmoor a special place indeed.
Happy birding!
Sally Anne
*photo: Steve Maslowski/USFS
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