Plan Your Weekend: Prowling for Owls and Other Birds

Posted in Programs and Events, Wildlife on November 7 2008, by Plant Talk

Has the Resident Pair Been Displaced by Youth?

Debbie Becker leads a free bird walk at the Garden every Saturday from 11 a.m. to 12:30 p.m., beginning at the Reflecting Pool in the Leon Levy Visitor Center.

Now that the trees are shedding their leaves, I’ve begun taking the weekly Bird Walk group through the Forest in hopes of seeing the resident great horned owls. Sure enough, a couple of weeks ago we discovered a large great horned owl (GHO) perched on a low branch.

At first we could not decided whether it was the adult male or the adult female of the regular pair. (The male is at left in the photo, taken last year during their courting phase.) Upon closer inspection we decided it was neither; it was one of their offspring. It has been months since the babies fledged the nest. So what was this immature owl still doing in the Forest? Great horned owls reach sexual maturity after two years, but their territoriality begins almost immediately after they learn to feed themselves.

Could it be that the mature male has reached the end of his reign as the only male owl in the Forest? He is, after all, more than 20 years old. That is a long life span for a wild owl (captive GHOs can live up to 30 years), although the owl pairs in Pelham Bay Park and Van Cortlandt Park have been breeding for almost the same amount of time. Human encroachment has given them a unique domain: The highways and complexes around our forests have created a closed habitat, ensuring enough food, safety from many predators, and a long life span.

The time comes for all creatures when they get too old to go on or they are pushed out by the next generation. Observing the younger owl in the Forest saddened me and the birders on the tour, as we know it could only mean one thing: Our resident great horned owls may be pushed out by a more vibrant male that will take over the Garden’s Forest and begin looking for his own mate. It is a somber time for the resident birders. We are all getting older and in danger of being replaced by someone fresher and younger. Sadly, to everything there is a season, even for the great horned owls of The New York Botanical Garden.

Join us on Saturdays at 11 a.m. to look for the great horned owls and other birds of the Garden.

Learn more about the Garden’s resident great horned owls after the jump.

The resident great horned owls (GHOs) at NYBG are always a must-see on the birding tour. During the months of summer when the deciduous trees are fully leaved finding the owls is more than a task—it is almost an impossibility. Owls are nocturnal and roost in trees during the day. They usually find trees that are leafy or evergreen because of their camouflaging cover. On the weekly birdwatching walk, I take people into the Forest to look for the owls. We use our binoculars to peer into the trees searching for large, dark objects sitting on a secluded branch. As the fall turns into winter and the trees shed their leaves, it becomes easier to find this elusive bird.

The great horned owls of NYBG have been nesting in the Garden for more than 20 years. I know because I have been watching them for all that time. I have witnessed the traumas of their lives. The male owl is on his third mate. The first female died of an unknown cause—her body was found at the bottom of their roosting tree. The second female stayed for one breeding season and then left. The third female has stayed but barely seems to tolerate the male. The two are usually in different trees until the end of December, when mating season begins. As breeding time approaches, you will often find them side-by-side sleeping in a tree. They are a great sight to behold: Two large owls sitting together on a bare branch.

But the real fun begins at sunset when they awaken. The male will begin his courting ritual with several hoots that are deep and quite demonstrative. If impressed, she will hoot back. He is really the only male in the woods, so hooting back, for her, is probably instinctual more than selective. Once they establish interest in each other they will sit on a branch together and he will try and mate with her. Even though the male owl has done this several times over the years, he has yet to master the act. Often he will knock her off the branch and they will both clumsily tumble to the ground, only to fly up to the branch and try again. He must be doing something right, because in the 20 years I have watched them, they successfully nested 18 times, not a bad record. Last year, they had two owlets. We watched as the large whitish-gray chicks matured into adult owls and began testing out their wings by jumping/flying from one branch to another. We clapped like proud parents as they took flight.

Once an immature owl is able to fend for itself, the parents will drive it out of their territory. The immature owl will need to find a home elsewhere. The Garden’s 250 acres are enough to sustain two adult great horned owls. In order to protect their territory and improve the genetic pool, the offspring are pushed out of the established parental territory.

Check out all of Saturday’s Programming.

Check out all of Sunday’s Programming.