Buillding Nests
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| Pileated Woodpecker |
May 1, 2003
A female Northern Cardinal landed on a small Spanish Mulberry shrub. She appeared to be foraging and I wondered what she might be choosing to eat. The handy binoculars revealed that she was biting and twisting small, dead twigs. She tested a couple before choosing one of a lesser diameter. With a twist of her heavy, reddish, seed-eating beak, she broke the twig and deftly manipulated it in her beak – presumably to obtain a more balanced grip – then flew in a “beeline” toward a nearby shrub. A couple of bright, red males came out of nowhere to follow her. But, they fell to squabbling as the female went about the process of building her carefully concealed nest among the vines covering a Yaupon shrub. Later, she flew higher into the canopy of a Post Oak tree and gathered some Spanish Moss. As she flew back toward the nest, a long ribbon of moss trailed behind her. The two males again challenged each other for her favors. I wondered which of the two would ultimately win, but how could I possibly tell? After all, male cardinals all look alike – don’t they?
As I contemplate the life of birds and the importance of nesting success on the survival of their species, I feel a kinship with them. After all, we nest in the woods too. Every year, we drive our mobile nest into these woods, where we trim back the encroaching vines, trees, and shrubs and remove the fallen trees from the long, narrow entry driveway. We hook up to the electricity and telephone lines that we snaked through the woods years ago and shazaam! Our nest is ready again for occupation. This nest serves as a sort of wildlife blind from which we can observe nature through the surrounding windows. Most of the time, these woods are quiet except for the near-constant call of cardinals or the drumming of woodpeckers. But at times, the woods come alive with assorted birds and other animals. This year we have even seen a Bobcat a couple of times as it walked close by and ignored us in our motorhome/blind.
Every year, a pair of Carolina Wrens finds our motorhome to fit their exacting requirements for a nesting site. Pat finds them a little exasperating at times because during the process of nest-building, they perch close by and their vocalizations are so loud that it is difficult to hear the softer and higher pitched sounds of the warblers and vireos that we seek. This year, the bird fauna seems to have changed somewhat. We still see most of the resident birds, but there is a new sound in the woods. Since I am deaf to the sounds of small birds, I depend on Pat’s excellent ears. “I hear a Northern Parula,” she might say. And, sure enough, searching through the Spanish Moss high in the canopy, we find the colorful warbler. But since we hear many of these sounds only once each year, some of the vocalizations are confusing. For example, this year Pat announced that a Red-eyed Vireo was singing in the tall Water Oak behind our motorhome. But, after a long time of searching, it was revealed to be a Yellow-throated Vireo. We have also seen and heard the Red-eyed Vireo, but now Pat is a little confused about the songs of these two birds. To confuse the issue, even more, we have also seen the Blue-headed Vireo which has a higher-pitched vocalization similar to that of the Red-eyed Vireo. Oh well!
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| Yellow-throated Vireo |
But the new sound in the woods is that of a warbler. Its song is not continuous. It sings a few times and then stops. We searched through the woods for days without obtaining so much as a glimpse of this bird.
In the heavy woods, determining the direction of the source of the song can be a challenge. Often, Pat hears the source of the bird and points in that direction so that we can both try to find it visually. Then, she may turn around 180 degrees and swear that the source of the song has changed. It is now in the opposite direction. Are these birds ventriloquists? But by walking quietly through the woods, usually, she is able to triangulate to the source of the birdsong with sufficient accuracy that we often find the bird. Although determining the direction of a hidden warbler is difficult, it is even more difficult to determine the height in a tree where a bird is singing. Apparently, in the evolution of the human species, determining the sounds of prey or predators was most important at ground level. There was no major adaptive advantage for primitive humans to determine whether a small warbler was in mid-canopy or in the tree top. There is not a lot of meat on a warbler, so these birds have probably never been an important source of food for humans. But to an owl perched in a tree, the height of its prey is critical. Consequently, owls have an evolutionary solution. The elevation of the ear openings on the head of a Barn Owl is asymmetrical so that one ear is higher than the other. As a consequence, a night-hunting Barn Owl can determine the elevation of its prey with sufficient accuracy that it can successfully hunt by sound alone. Humans can attempt to mimic the Barn Owl by turning their heads sideways so that one ear is higher than the other. But success with this tactic requires practice.
Anyway, our new warbler evaded us for days till we finally saw it foraging in mid-canopy. Previously we had not been able to determine if it was foraging in the low, mid or high tree canopy. It had a bold eye-ring, gray head, and yellow throat and breast. It was clearly a Nashville Warbler. As is often the case, once we have identified a new bird or its song, then we see it over and over. So now we know its distinctive, four-part vocalization – at least for now. Will we recognize it again next year? Who knows!
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| Nashville Warblers |
Now that we have spent almost a month in these woods observing nature, we have made other observations that distinguish this year from others. Mainly, we have seen lots of birds nesting. It started when I observed a spider-eating, Ruby-throated Hummingbird building its small nest on a branch about 20 feet up in a Post Oak tree. It was very busy for a couple of days as it molded the small, cup-shaped nest and adorned the outside with lichens – maybe for camouflage. Then it disappeared only to return sporadically a couple times in a couple of weeks. Now the small nest remains empty and we can only speculate on the fate of the nest builder. A second very interesting hummingbird has been seen twice. It appears to be an albino hummingbird – or at least partially albino – if there is such a thing. Its back and tail are mostly white. I find nothing like it in our American bird books, although it seems likely to be an albino Ruby-throated Hummingbird.
One of our favorite birds of the woods is the White-eyed Vireo. This year, a pair built a delicate little nest low in a bush beside our motorhome. I was excited with the possibility of obtaining some photos of their nesting behavior. But, the next time I looked, the nest had been destroyed by some competitor or predator and the vireos were dispersed. Later, I found another, active nest of these vireos. They actually built two nests about two feet apart. Some birds have been known to build “dummy” nests. Brown-headed Cowbirds parasitize other birds by depositing their eggs in the nests of other bird species. These birds then rear the fast-growing Cowbird instead of their own. So some birds have developed defensive tactics against the Cowbirds. They build “dummy” nests for Cowbird egg deposition and another nest for rearing their own young. Maybe that is the reason the Vireos built two nests so close together. Anyway, I got some good photos of these pretty, little birds building nests.
We have also watched a pair of the large, crow-sized, Pileated Woodpeckers raising their young in a hole high in a dead Water Oak. These often shy critters have been very tolerant of our presence. The young are now big enough to noisily stick their heads out of the hole and demand those tasty, regurgitated wood ants from their hard-working parents.
This year we have also been fortunate to find Carolina Chickadees and Tufted Titmice nests in old woodpecker holes. Although we cannot observe the feeding activities in the nest, it has been fun watching the parents foraging for the camouflaged insect larvae that are so plentiful in the woods during the spring.
When we leave every year to goof off in other parts of the world, we often consider the possibility of selling. After all, we generally use it for only one month every year. Also, it can be a hot, steamy place in summer and the mosquitos, ticks, chiggers, and assorted biting flies can leave our skin a little pock-marked. But, we have owned this property for over 30 years and it is the closest thing to a permanent home that we have. Every year when we return to these woods, we get a sort of “spiritual” boost that includes some feeling of euphoria. It is a special, natural place where we remember our kids playing in the woods or in the creek or swinging on a high tree swing. It is a place where we can be either reclusive or social, depending on our moods. There are no close neighbors to pollute our air with loud noises. It is a place where we can be in touch with the world via the Internet or in touch with nature via our senses. However, there is a commercial demand for this type of “cabin” property with lots of trees and on the banks of a stream and relatively close to the Bryan/College Station area, so we sometimes think about the nice, new motorhome that could be purchased with the proceeds if we sell. School, city and county taxes have risen dramatically every year and we are penalized with higher taxes because we do not clear the woods and attempt to turn it into a money-making farm or ranch. The thought of selling this private nature preserve to someone who would bulldoze this small piece of nature is repugnant to our sensibilities. But, our kids will likely have little use for these woods when we are no longer around. So, maybe dozing is inevitable.
For now, we have decided to keep and enjoy this property till -- for whatever reason – it becomes necessary to sell it. Consequently, it will remain our nesting place and our permanent home! At least as permanent as any home can be.
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