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Youth Birding at North Branch Nature Center | Home | Join | News | Discussion Forum | Resources (updated 1/12/10) | Quiz | This section of our webpage is still evolving, but the previously unused forum has been eliminated. The "Discussion Forum" will now be a place to share stories from near and far, like an online journal for past and present members of your Youth Birding Program. If you wish to submit an entry, we will be happy to post it! Tales from Texas
(Skip to an Installment: 1, 2, 3, 4, 5, 6, 7, 8, or 9 ) Howdy! For the next three months, I’ll be sending updates from my current field season with Golden-cheeked Warblers in Kickapoo Cavern State Park, Texas. For this first instalment, here are some background details of who I am and what I am doing: About me: My name is Alyssa Borowske; I am a 23 year old North Branch Nature Center alumnae whose passion for birds led her from Central Vermont, to Iowa, Michigan, New Zealand and Texas, all en route to pursuing a career in avian ecology and conservation. For the bird-nerd highlights of my last several years... I enjoyed birding and participating in Cornell’s Project Feederwatch with my family; then with NBNC, I ventured to Cape May, New Jersey twice for the World Series of Birding and went birding in Costa Rica in 2001. My enthusiasm for researching rather than simply watching birds was sealed when I began volunteering with a raptor migration project at my college (Cornell College, Mount Vernon, Iowa) and spent the summer of 2006 banding songbirds at the University of Michigan Biological Station. After graduating in 2007, with a degree in Biology and Environmental Science, I spent a year as a Fulbright Fellow at the University of Waikato, in New Zealand. I investigated the responses of two suburban bird species to non-native magpies and mynas. Which brings me up to the present...between returning to the US in December 2008 and beginning a PhD at the University of CT in September, 2009, I am a field tech chasing Golden-cheeked Warblers (GCWA—go ahead and pronounce it “gick-wah”) in Texas... About the birds: Despite the risk of anthropomorphizing, anyone who has spent time observing birds will tell you that each species clearly has its own personality. The personality of GCWAs? Positively endearing. Golden-cheeked warblers are the epitome of that cocky/confident type who know they are gorgeous and aren’t afraid to shout it out to the world, but are somehow chill about it too, as though knowing they are cool confers a degree of invincibility and leaves them no need to get too worked up about anything. Simultaneously spunky and mellow, GCWAs are fabulous birds to study. In the field, it is easy to spot the bright yellow and black of the males (pictured on the right) as they perch in the shrubby treetops and sing out their territory claims. In the hand, they are calm and cooperative. Females, of course, are a lot more secretive—I actually have yet to spot one. The song is also fortuitously distinctive: the primary “A” song is a “Zee Zee ZeZee zoooooooo Zee!” which is reminiscent of the black-throated green, but slightly lower, slower, and with a different cadence. About the predicament: Cocky and confident as each individual GCWA appears, the species, as a whole, is endangered. Unlike for more adaptable—and therefore more abundant—species, only scrub country dominated by ashe-juniper trees which are at least five meters in height spells “breeding grounds” for the GCWAs; they typically nest in juniper trees and juniper bark is the nest construction material of choice. If the vegetation is not quite Picture by Dianne Dessecker About the project: I am employed by Texas A & M University to assist a master’s student with her field work. The thesis project is looking into the effect of habitat characteristics (namely tree species composition and density) on GCWA presence and productivity. This project involves mapping territories, searching for nests, banding individuals, and (hopefully) setting up nest cameras. We’re also helping out with a few auxiliary projects, so we’re doing systematic surveys for GCWAs, Black-capped Vireos (also endangered) and their predators in habitat patches throughout the range and along some roads. It is exciting to be exposed to such a variety of field techniques and to be working directly with an endangered species—since I intend to go into avian conservation, this project is a perfect fit!
In the last few weeks, the Golden-cheeked Warblers (GCWAs) have returned to Texas after spending the winter in tropical Mexico and Central America (actually, very little is known about wintering GCWAs...) . The males are out in claiming territories in the prime real-estate of the TX Juniper scrubland, and waiting for females to arrive and express interest...any time now, they’ll begin pairing up and building nests. Without a doubt, a busy time for the little guys—and a busy time for field techs, too! Our job has been to go out into the scrub, armed only with binoculars and a GPS unit, and search for birds. Easy, right? The way it works is that, just before dawn each day, the whole crew drives out to a field site (which is an adventure itself, we coax our trucks up and down some pretty intense terrain!). From the central parking location, we radiate out on foot, following GPS points which are scattered systematically throughout the habitat patches. For these initial surveys, we weave our way through the vegetation to the GPS points, stopping along the way to listen for and follow GCWAs! When we hear the telltale GCWA song, we deviate from the GPS points and follow the bird instead, marking waypoints as we go so that we can create a map of each bird and his territory. Following a GCWA is like playing endless game of Extreme Marco Polo. The basic rules of chasing an unseen opponent based on their vocalizations is the same; the differences are that I am scrambling through scrubland rather than splashing around a swimming pool, my calls of “Marco” are silent pleas of “sing for me...hold still...perch higher!,” my eyes are open to prevent the otherwise inevitable self-destruction of stumbling around blind, and physical tagging is replaced with “mere” visual contact. Sometimes, the bird is perched out in the open and the chase is relatively straightforward; other times, it feels less like a game and more like I am a wondering soul chasing fairy bells ever farther into the distance—elusive bells (er, birds) which remain tantalizingly close but perpetually just out of sight no matter how much ground I cover in pursuit. But I enjoy childhood games and United Kingdom myths...right?! You bet J
Vegetation: Sometimes the trees are intermittently spaced throughout relatively open areas which are easy to walk through. Granted, these areas are not high quality habitat for GCWAs. Much of the time, then, the vegetation is so dense that there is no obvious way through or around, but dense, sparse, whatever, we plow through it all! This wouldn’t be so bad if we only had Juniper to contend with (although this is sometimes easier said than done), but it seems as though the majority of plants out here are on the defense—with thorns, spikes, and prickly parts! I’m quickly learning which plants have spiny leaves, which have thorny stems, and which simply have more spike than leaf and branch combined, etc. Surprisingly, although we are in cactus country, the cacti are actually the least problematic of the prickly plants because they are low to the ground and fairly easy to avoid—unless you are unlucky enough to get too close (in which case you’ll be pulling spines out of your skin and clothes for some time...). Rocks: In this scrubland, the limestone bedrock is never far from the surface, and the shallow soil is impressively rocky, meaning that the ground is consistently littered with (or completely covered with) limestone blocks, ranging in size from small boulder to chip, and oddly shaped chert nodules which formed within the limestone and have been extricated through the erosion of time. In dry weather, the ground—and especially the slopes--is rocky enough to be unstable, and in wet weather, the otherwise-sturdy exposed bedrock is slick and dangerous, too. These rocks give us the choice of walking quickly or walking safely, and even the most careful walk tends to resemble a drunken stagger... Topography: As most of this region (as in more or less the entirety of the GCWA breeding range) was or is still actively used for ranching, the majority of the extant mature juniper stands are in the steeper, less accessible areas. This means, of course, that we are perpetually scrambling up and down the short-but steep hills which for which the “hill country” were named. We also frequently ford streams and rivers—a difficult task except that each is a pebbly vein across the land which only sees water during flash floods— which are rare but fierce in this drought-parched zone. view of a Juniper stand and a slope I just scrambled up... Animals: pigs, and cows, and rattlesnakes, oh my! Yep, the wildlife here covers the range from totally harmless to more or less deadly, and from ubiquitous, to downright rare. For instance, armadillos are common and harmless, as are the many species of deer (mostly exotics); wild pigs are slightly less common and significantly more dangerous... rattlesnakes are even less common and even more dangerous...mountain lions are much less common, and technically more dangerous (although that’s not very likely)...nothing worth being paranoid about, but definitely enough to keep us on the constant alert! Protocols: instructions and permits don’t represent dangers, but they are challenging nonetheless. For instance, because GCWAs are endangered, we are technically supposed to stay at least 20 meters away from them, but somehow attain and maintain visual contact. In the dense vegetation. While the birds flit from tree to out-of-sight tree. Right. I have a feeling that the person who came up with this protocol has never attempted to follow a GCWA through as he meanders through his territory on a path only a bird can navigate...but we’ll give it our best effort...! But, despite the dense vegetation, the steep, rocky slopes, the risk of thorns and poisonous bites, and the Super-tech skills demanded by the protocols, where the GPS or the GCWA says to go, we follow! Already, I’ve walked along precarious hillsides and plunged myself into impossibly dense vegetation which I usually wouldn’t even think about walking along or shoving myself through, but it is this sort of challenge that makes the job fun. If I didn’t want which would test my patience and stamina on a daily basis, I wouldn’t have signed on in the first place. And, if experiencing a taste of the Texas frontier circa 1850 from the safety of the 21st century is your idea of an adventure... and if the mere thought of getting paid to wander around in wild country and then sit back and admire an adorable little warbler as he shows of his plumage and vocal abilities to the world launches you into a mental happy dance...then you’ll understand that the rewards more than justify the challenges. To a human, at least, each Golden-cheeked warbler (GCWA) looks and sounds downright identical. Consequently, when we spot a bird, no matter how lovely a view we get, we have to extrapolate his identity by comparing his present location to past sightings of a bird in the same general vicinity. The assumption is that if we see a bird in the same spot on a different day, it is probably the same individual, but we cannot be 100% sure that it isn’t just the same tree but a different bird. That’s the situation, but there is an, albeit labor-intensive—solution to keep track of who the territory owners are: color banding! It is quite exciting; after wandering around our study sites chasing birds and taking GPS points of their locations, we are actually succeeding in relocating most of the GCWAs right where we thought we would, which means we are actually identifying territories! Because the birds are still in the courting/nest building stage, they are extremely territorial. Territoriality is useful for us because it helps us locate the birds and because we can take advantage of the birds’ (generally) quick response to intruders and catch them individually via target netting. The theory is simple: if we set up a strategically-located simulated territory intrusion, we can draw the male in; if he flies into the net, we can adorn his legs with a particular pattern of colored bands. These bands provide him with a unique identity code; if we spot a banded bird well enough to determine the order of the colors, we can know without a doubt exactly which bird we are admiring. Luckily, the practice is almost as simple as the theory... Two of us (Jessica, the MA student, and one of the field techs) heads out first thing in the morning with posts, pole, net, and banding gear. We select a target bird, hike out to his territory and, if we can hear him singing, find a vegetation-free corridor within which to set up the net. The perfect corridor is wide enough that the net doesn’t get tangled up with twigs and leaves, but narrow enough that the birds will have nearby branches to perch in. The mist net is standard banding paraphernalia; a long and tall net of fine black mesh, strung so as to create four tiers of “pockets;” the idea is that the birds cannot see the net, so they fly into it and fall into the pocket, where they hang until a researcher carefully extracts the individual. For target banding, we take the process one step further by placing a little field speaker on the ground in front of the net. From this, we broadcast a recording of a male GCWA, mimicking a territory intrusion in the hopes of luring the rightful territory owner into the clearing and into the net. Tenuous as it sounds, most of the time, it actually works. And, watching it happen, is quite an experience! Jess and I sit, just a few meters and a couple of juniper branches between us and the net, trying to remain statue-still and ignore the rocks and sticks beneath us...at Jessica and I lower the net to a comfortable height, and one of us slowly, cautiously, extracts the little warbler from the black threads. As he has only been netted for mere moments, and GCWAS are docile in hand, they are never badly tangled, and removing them just takes a few confidently cautious maneouvers; find the clear belly, slip the net from the shoulder of one wing, hold a gentle finger against the bill to slip the head free, check to see if the other wing is caught, then finally tug the net from the vainly grasping feet. Free from the net, we slip him inside a cloth banding bag and take him over to the banding station—being sure to close the net behind us! At the banding station, we carefully affix three small rings of colored plastic, and one ring of metal around his ankles; the colors mark the identity code, and the metal band contains a unique number, so he can be identified even if he is caught again by someone else. Bands in place, we set him free; from initial entrapment to final release, our entire rendezvous takes less than ten minutes—probably closer to five. The process might be traumatic for the GCWA, but not too much—we can hear him singing again almost immediately, as if to make up for lost time. For us, though, holding that little guy is an electrifying experience. It is not to be done lightly, of course, but there is something about the silky feathers, the heartbeat which seems to reverberate throughout the entire tiny body, the bill which occasionally pecks at giant human fingers...which is simply magical. A bird in the hand is most certainly not worth ten in the bush as far as conservation of endangered species goes, but a bird in the hand is an ineffable experience which, for me at least, will never lose either its gravity or its thrill. Intricacies of Conservation: For the “Statewide” component of the Golden-cheeked Warbler (GCWA) and Black-capped Vireo (BCVI) projects, the primary goal is to determine where (and in what abundance) the two species are located. The secondary goal is to identify correlations between these locations and habitat characteristics so that we can (a) better estimate where GCWAs are most likely to be found, and (b) determine how habitat should be managed to increase GCWA productivity. Using GIS software, patches of key potential GCWA habitat were identified throughout the entire range. These patches were chosen primarily based on density of juniper, which is visible from aerial photographs and satellite images. Ideally, we would survey points in every patch, but, while some of the patches are on public land, such as parks and natural areas, many are on privately owned ranches. This logistical first step of gaining landowner permission to look for GCWAs and BCVIs can be a bigger challenge than navigating the rocky slopes and juniper stands... As a field tech making these calls, each phone number is just one square in our Excel database, but dialling is a game of chance. Even if I am lucky enough to reach the right person the game may play out in any number of directions: “...Hello?” “Hi, my name is Alyssa Borowske; I’m a researcher with Texas A & M University. We’re conducting songbird surveys throughout central Texas and are wondering if it might be possible to conduct surveys on your property...” “...sounds like an interesting project...no, I don’t have any more questions...I’m always here, just call before you come” “...sure, don’t see why not...but you sure you want to come now? The birds are so much better when the mulberry bush is in bloom...”
“...oh...we’re getting old...we’re not interested in anything like that” “...actually...I just don’t trust you...I just don’t trust you on my land” “...well...it might be possible as long as you ain’t working with no endangered species or nothing...” But, of course, we are working with endangered species, and if the conversation comes to this point there is nothing to do but tell the truth and hope for the best. If a landowner says no—which many do—we immediately thank them for their time and hang up the phone—absolutely no arguing or requesting justification. The “no” answers can stem from a variety of reasons. Some landowners simply don’t like having strangers on their property. Others are leery of false motives; for instance, during training, we learned of a situation in which a group of people posed as researchers from Texas A &M and called landowners to get entrance permission while, in reality, they were searching for natural resources on behalf of a private company. Many of the “no” answers, however, are simply products of the challenges inherent to conservation-based field work: regulation vs. private individual and science vs. hearsay. Regarding the first challenge, many landowners are worried that, if we confirm the presence of endangered species on their land, we will alert government agencies which will tell them what they can and cannot do on their property. For this project, the information we collect is 100% confidential and will not be used in any way which connects bird sightings to particular properties. Even so, many people would rather guard their privacy with a quick “no” than risk the consequences. For this type of project, these responses are unfortunate but ok; in the long-term however, they pose a more significant problem. The obvious goal underlying work with endangered species is to learn more about the species and its requirements so that we can help stabilize—or even reverse—the population decline. To approach this conservation goal, especially in a case like this in which the primary threat is habitat degradation, landowner support is a must. It would be easy to say that the people who want the government to stay out of their prospective plans to remove stands of juniper are simply paranoid and uneducated and clearly don’t care about GCWAs, but the actual situation is much more subtle. The quick synopsis is this: in the Texas Hill Country, ashe juniper is native and was abundant prior to European settlement. For the last hundred and fifty years or so—basically the entirety of collective Texan memory—juniper has been suppressed due to ranching and fire (and some logging). Consequently, many Texans believe that the juniper, and golden-cheeked warblers along with it, is non-native. Alternatively, some people realize that the juniper is native, but view it as an invasive species. For instance, we have Hill Country flora field guide/conservation narrative which was written by a woman who works at a nature center and was published by Texas A & M. The book’s discussion of juniper focuses entirely on the strategic control of juniper as a native-yet-invasive weed which is disliked because it consumes water which could be used by more valued species, prevents the regrowth of other species (junipers have dense branches allow little light to permeate), and is inappropriate browse for deer. In regard to GCWAs, all the book says is that GCWAs build their nests from the strands of loose bark on mature junipers, but that the birds prefer to nest in deciduous species, especially in ravines. In actuality, GCWAs select nest sites based on tree height more than tree species and are often found in areas with steep terrain only because dense juniper stands are rarely found in flat areas. So, what’s the answer? Does juniper belong in the Hill Country in large, dense, stands, or are these products of an invasion which should be thwarted? Should we encourage the spread of a habitat type which is critical to one (albeit endangered) species but marginal or undesirable for many other species? Is it logical to manipulate nature with the goal of reclaiming a more “natural” state? Is it just a question of timing and perspective? Of semantics? If only we knew...but at least asking the questions and attempting to envision possible perspectives is an important first step. From territories to nests... Just a few weeks ago, our territory visits were relatively straightforward. Typically, (assuming mild to moderate wind), one of two scenarios would take place when we approached a territory point (i.e. a spot at which we had previously seen or heard a bird and taken a GPS waypoint). Either we would hear the bird immediately, or we would pause and listen, but hear him within a few minutes. We might have to stop and listen in a few locations, but finding him generally did not take long. Then, once we had heard the bird, following him was (generally) relatively easy, because he would perch in treetops and project the classic “A” call virtually non-stop, simultaneously patrolling his territory, declaring his status as an eligible bachelor, and helping us out immensely! For the last couple of weeks, however, this process of locating and stalking GCWAs has been growing progressively trickier. The difference? Two things: females and families. In turn, our field focus has shifted from mapping territories to evaluating productivity, or how far along in the nesting cycle a particular pair is. A singing male gets a Vickery index score of 1; a male and a female together get a score of 2; nest-building or copulation behaviour gets a score of 3; etc, up to nest success or failure. You might think that having two birds to look for would make GCWA spotting easier, but that’s not quite how it works. First off, the males, no longer bachelors, but full breeding males with established territories and mates, have shifted from ostentatious singing to something a little more subdued. They still sing, but more commonly with a mix of the loud A call and the quieter B call, or, with a quieter-yet version. That’s right, GCWAs can “whisper!” And, he might call just once or twice, and then remain silent for several minutes, during which time he may stay put or may fly to another tree. In general, they are simply more unpredictable, more difficult to hear, and more difficult to locate visually than they once were. Second, females may or may not be right next to the males and, as singing is almost entirely a male GCWA activity, finding the females requires an ear tuned in to the GCWA chip note (a skill I am slowly acquiring...) and the unreliable luck of being in the right place at the right time. For instance, in one territory, I had heard the male, but then lost him. After waiting for several minutes, I decided that I should move on, so I was looking down at my GPS when I heard the wingflaps of a bird flying close by. I looked up, and saw a female GCWA, at eye level, not five feet away. Granted, she didn’t stay long; after eating a juicy green caterpillar (the GCWA food of choice for this time of year), she vanished into the impossibly dense vegetation of a juniper tree. Despite the challenge, it’s our job to be patient stalkers; excitingly, we have heard and/or spotted females with greater than half of our 50+ males, and it is likely that there are many other females in the area which we haven’t spotted yet. Finding females is, itself, exciting, but it is also important because females are our most reliable cue for finding nests. We want to find as many nests as we can so that we can get a better feel for nest success rates and nest-tree requirements. Ideally, we would also like to place cameras at the nests so we can observe parental behaviour and document predation events. Of course, nest-searching is an entirely new type of adventure. Golden-cheeks are small warblers, so the nests are comparably diminutive. They are typically built in inconspicuous, semi-concealed locations, generally between three and five meters off the ground—but sometimes higher—and often in small forks in the branches. The nests are constructed from juniper bark, so they are extremely well camouflaged in juniper trees, and blend in well in oak or pinyon pine, too. Because they are so difficult to spot (even if you know which tree to look in), the best way to find a nest is to use behavioural cues. We have a window of approximately a week during which the female ventures off, finds a mature ashe juniper tree, peels off a strip of bark, and uses a collection of these strips to weave together a delicate cup-shaped nest. When she isn’t eating, she should make approximately five nest-material collection trips per hour, so there should be ample opportunities to witness this process. So, most ideally, we will see a female carry nest material to the nest itself, or at least the nest tree, or at very least in the general direction of the nest. For several of our pairs, we have identified areas of particularly tall trees around which the birds have been acting particularly “suspicious,” and we have even seen a couple of material carries. In these territories, we take our time, with a combination of careful bird-stalking, staring with blind hope into the network of branches in promising-looking trees, and waiting in prospective prime spots in hopes of witnessing a telltale material carry. Needless to say, even the most adept GCWA nest searcher will search for many more nests than she will find, and will find those based primarily on luck. Here at Kickapoo, we haven’t had our moment of luck quite yet. We did, however, take a field trip to Garner state park where another grad student from Texas A & M is conducting a similar project on GCWAs. This field crew has actually found three nests; one from last year, one recently finished, and one in construction. The field trip was both reassuring (yes, nests can be found!) and daunting; even with a person standing by to give visual directions the nests were extremely difficult to spot! It was definitely helpful to get a better idea of what we are looking for, though, so hopefully it will help! The Kickapoo nest squad is on alert and it’s only a matter of time....right?! To let you vicariously experience the daily adventures of a Statewide project field tech, here is an expanded version of my field notes from last week.
Now that I am back at Kickapoo State Park, after spending three weeks on the Statewide project, I’ll expand my field notes from the last few days to give you a feel for the “standard” work day—and let you in on some of the exciting updates! The general goal of our daily work is to track down target Golden-cheeked Warblers (GCWAs) and follow them around to (hopefully) determine their nest-stage.
A nestling saga... It is approaching the end of May; as reported by Texas A & M graduate students working in other parts of the Golden-cheeked Warbler (GCWA) range, GCWAs are done with the nesting season; parents are busy feeding their offspring which, in turn, have fledged and are growing increasingly noisier, more mobile, and more self-sufficient. So, for a researcher, finding GCWA fledglings should be a cinch, right?! I kept reiterating those “facts” to myself on Friday, May 22, as I employed my most refined bird-stalking skills to search for fledglings I simply “knew” had to be there. Why the confidence? Well, my morning had gone something like this: First stop, territory number 8 (the pair with the first nest we found). From what we can tell, these birds went from incubating eggs to simply hanging around the nest; even with patient observations, we never saw food carries or heard nestlings, and certainly have not seen fledglings. Predation? Nest Parasitism? Hopefully the video will show what happened! My task for today was to try to find the birds and determine what they were up to. I spent some time sitting near the nest, but didn’t hear anything, so I began wandering slowly through the territory, but with no better results. Eventually, I heard a GCWA, way off in the distance. Judging by the direction of the call, I figured it was not the bird I was looking for, but, since the neighbour was also on my list of birds to check in on, I decided to abandon my search for number 8 and head off to follow number 9. This bird provided quite the game of chase. He would sing once, maybe twice, and I would head toward the sound. Each time I progressed through the juniper, I would hear him again, but farther off. In this way, I covered a couple hundred meters or more, ever-following the elusive GCWA song. Eventually, he led me out of the juniper thicket and up a small slope which was sparsely vegetated with clumps of short, slightly scraggily juniper bushes. Ah, now nice to stand without sticks poking into my back and snagging at my hair (an endless, losing battle!), but, even after several minutes, I didn’t hear the male sing again. What I did hear, however, was chipping. Over the last couple of weeks, my ability to identify a GCWA by the chip note has definitely improved. This is due primarily to the fact that there are times at which the GCWAs chip positively incessantly! The last time I had heard chips like this was when I found the pair with the first fledgling. Coincidence? I don’t think so! Today’s pair (for the chipping was coming from the female as well as the male—apparently I had followed him all the way to his mate!) definitely had something to be excited about, and I was going to find out what it was! At first, I was extremely cautious. I could see both the male and the female, each about 20 feet from me, and about the same distance from each other. They were flitting about; first on one spindly juniper branch, then another, chipping continuously. Very occasionally, the male would sing, generally an aborted version of the A or B call (which is conveniently lumped into the catch-all category of “C” call). After several minutes, I began to slowly inch my way closer to the birds, and, at times, they would flit closer to me as well—sometimes within feet. I’m still enchanted by these moments in which I seem to meld into the background and get to watch these charismatic warblers as intently as I desire. I watched the female or the male, depending on which was more readily viewable and, eventually, I saw each of them carry food. Each time this happened, I would try to visually track the bird’s path as it bounced from one branch to another, one bush to the next. An unbroken visual connection was never possible and, I would watch the bird suddenly emerge with an empty bill without ever being able to determine where the insects were deposited. I was certain that the pair was feeding fledglings, but where were they!? The other fledglings I had found were perched fairly high up in juniper trees, and chipped their own miniature version of the GWCA call note when the parent approached them with food. But, now, I listened for the notes, and heard only the parents. I scanned the branches of the trees, and saw nothing but empty perches. Yet, as I watched, the pattern repeated itself several times. I began wondering—not seriously, of course—if the pair was simply feeding imaginary fledglings which did not actually exist! I began walking around, systematically looking up into each bush. And then I saw it—not a fledgling but a nest! Mystery solved. My confidence that there were fledglings had made me oblivious to the true pattern. The parents really were carrying food to a particular location, but nestlings tucked within a perfectly-formed cup of juniper-bark in the crock of the main stem of one of the juniper shrubs. The bizarre thing is, the nest was almost at eye level—not quite 6 feet of the ground, and the tree could not have been taller than 8 feet. NOT the sort of habitat GCWAs are “supposed” to nest in! I radioed my boss, then sat back and watched the nest from afar while I waited for her to arrive. Now that I knew the secret, the pair’s behaviour was downright obvious. Both the male and the female made frequent quick visits to the nest, sometimes carrying food, sometimes not; once I saw the male fly off with a fecal sac. All the while, they were flitting around and chipping, as I had observed for the last hour or so. When my boss arrived, thrilled with my find and incredulous as to the location, she stepped up into the tree and peaked in the nest. Three nestlings! Pin feathers coming in, eyes open; definitely ready to fledge fairly soon. Very exciting! The next day, when we went back to band the nestlings, we could hear immediately that something had changed. From as far as 100 meters off, we could hear loud chipping—did the nestlings fledge?! But, an approach to the nest proved otherwise. Where three nestlings had huddled in the nest like sardines not 24 hours previously, now lay a single, large egg. The nest had been parasitized by a brown-headed cowbird. Judging by the parents, who chipped vigorously and carried food to the chick-less nest, the parasitism probably happened not long before we arrived—most likely around dawn. My boss “addled” the cowbird egg (shook it so it wouldn’t hatch) and we looked for the GCWA chicks, but they were nowhere to be found; cowbirds often eject host nestlings before laying their own egg and, although these nestlings were almost ready to fledge, such a forced fledging doesn’t bode well for their survival... In terms of my nest-find, the news is heart-breaking. It was so exciting to watch the parents and then peak at the nestling Final Days of the Field Season After three and a half months, the Golden-cheeked warbler (GCWA) field season is actually coming to a close. Technically speaking, “State-wide” surveys for Black-capped vireos will continue through the end of June and vegetation surveys here at Kickapoo will continue through the end of July, but the GCWA field work is basically done and I, as a GCWA field tech (with another job lined up for the summer!) have just a few days left in Texas. Hard to believe! As this is the first field season, (and way too early for data analysis anyway) there are certainly no conclusions to report yet, so I’ll fill this last update with some quick updates: “My” nest: The last update’s nest saga actually has a relatively happy ending after all—we have sighted a GCWA fledgling in the territory! Apparently the cowbird was, after all, late enough in its parasitism that the force-fledged GCWAS were able to survive out of the nest. We have only sighted one fledgling at a time (on two occasions), but the fledglings do not necessarily stay together, so it is impossible to guess whether there is more than one live fledgling or not. In either case, it is very exciting news! Nests in general: We found a grand total of 6 active GCWA nests; not a brag-worthy number, but a solid one. The most recent of our nest findings was actually in the incubation stage when we found it, and it was accessible enough for us to put a camera up for activity monitoring. Watching the video, however, should be quite informative, because we are afraid that the nest has been depredated; it is simply too quiet, and we often visit without seeing the parents at all. Plus, one of my coworkers actually saw a scrub jay hop around near and even look into the nest...not a good sign! This nest (as opposed to the one I found!) appeared to be well-hidden...but you can never predict the course of nature. Overall, I have definitely enjoyed the opportunity to see and compare the different nests. They have spanned the range from nests which were nearly impossible to see amid the top tufts of vegetation, to nests at open eye level. The construction, though, is amazingly similar; each nest is a tightly-woven vessel of Juniper fibers and provides a powerful example of innate skill! Five of the six nests were built in Juniper trees, and the 6th was in a pine. The fact that we did not find any in an oak could mean that, contrary to popular belief, GCWAs do not often nest in oaks, or it could mean that oak nests are more difficult to spot—which is certainly possible since the oak trees are often comparatively tall and sprawling, with epiphytic vegetation, lichens, and mosses clumped to the branches and obscuring our view.
We’re still sighting fledglings, not rapidly, but consistently. Overall, we have found fledglings at approximately half of our territories, which is slightly below the “standard” GCWA fledging rate of ~60%. There are a few possible explanations for this: 1) human error (always a possible confounding factor); 2) some of our territories were claimed by bachelor males (no mate and so no nest); 3) the nest success rate in this area is lower than the standard (which was measured elsewhere). So far, there is no way to differentiate between the explanations. Despite the fact that fledglings are supposed to become easier to find as they grow older, they are still hard find compared to their fathers! The last couple of fledglings that I found, however, were actually perfect encounters. For one, I had been searching for the male for some time, but had not heard him anywhere. Suddenly, though, I thought I heard a GCWA chip which didn’t sound quite right for an adult. I cautiously approached the chipping tree and, after a quick scan for movement, saw the fledgling flitting between branches. It was old enough to have mottled-golden cheeks, but its tail wasn’t fully grown in yet. The second encounter was very similar, except I heard the male first, walked in the direction of his song, and then heard the fledgling before I got to the male. Again, the fledgling was fairly old, and I didn’t have long before it moved out of sight, but long enough for a definite identification! Upcoming: Intensive vegetation work! All of the TX A&M grad students who are working with GCWAS are using the same protocols for vegetation surveys, but the grad student I work for is conducting extra veg for her project because she is specifically interested in the correlations between habitat characteristics and GCWA abundance and productivity. The main goal of the vegetation work is to quantify the percent canopy cover and tree species composition within and without the GCWA territories. What this means is that the entire study sites were fitted with a grid of points at 20 meter intervals. Within the GCWA territories (as mapped based on the GPS waypoints we took throughout the season), vegetation surveys will be taken at every point and outside the territories surveys will be taken at every fourth point. Each survey includes an estimation of canopy cover within a circle centered on the point, and an identification of all tree species within a 10 by 2 meter transect in each of the cardinal directions from the center point. The survey itself isn’t particularly difficult—the catch is that there are literally hundreds of points. The information will be extremely valuable, however, for helping us better understand the types of habitat which GCWAS actually need to inhabit in order to be successful. Overall, my experience this field season has been extremely positive. The tread on my hiking boots may have worn to smooth nubs, and I’ll be boasting killer tan lines for the rest of the summer…but I can proudly say that I have gotten to know one of this country’s most charismatic little birds (ok, I know, I’m biased now!) and, in doing so, have (once again) confirmed my passion for avian field work. Grad school, here I come! For those of you who are interested in learning more about my experiences working with birds here in Texas and in New Zealand, I will be giving a talk at the North Branch Nature Center on Monday August 10th; this will be a perfect opportunity for you to see pictures and ask questions! I hope to see you there!
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The realities of Kickapoo field work:
So, yes during these daily solo journeys through the scrub, the challenges are many and varied: 
first there is nothing to listen to but the scratchy and slightly too-fast GCWA voice emerging from our speaker and the episodic whoosh of wind in the junipers. Then, we hear it, an echoing song challenging the computer generated intruder. A few minutes later, the live song is closer... then, with an audible flutter of wings, the angry GCWA is over our heads and in front of the net, perched now in one tree, now in another, zipping across the clearing, so close to the net, but not quite in... until...with a slightly lower trajectory, he’s pocketed by the net which transformed his tough charge into an unceremonious upsidedown tangle. 
“...ah...yeah...um...so, what are you doing?” 
s—that’s the hard part of field biology, not becoming attached! Although it is possible that we cued the cowbirds in to the nest location, it’s not particularly likely. We made a point of listening and watching for cowbirds while we were there, and found none. But, cowbirds use the same behavioural indicators as researchers do to find nests, and this nest could not have been easier to spot. Nevertheless, in terms of the research, this little saga provides incredibly useful information. We now have documented a GCWA nesting attempt in a habitat which looks far from ideal, and we have confirmed that parasitism from brown-headed cowbirds is a very real risk in such open habitat. Such is the way of science; we learn lessons in observation, patience, and the importance of keeping a mind open to unforeseen patterns. And, we learn lessons in habitat correlation with species interactions; parasitism is an undoubtedly successful strategy—it is just difficult to accept it from the perspective of the host.
Fledglings in general: