The 2008 nesting season at Delaware State Park (DSP) and Alum Creek State Park (ACSP) are now history. One hundred-sixty-two nest boxes stand in DSP and 22 were used by Eastern Bluebirds to raise 122 young from 29 successful nests, a 28% increase over 2007’s total. Bluebirds continue to rebuild their populations after severe weather in February 2007 cut their breeding population by two-thirds.
Another indicator of recovery is the mid-May bluebird nest count. I counted 11 nests in 2007, and 16 this year, for a 45.5% increase. After a catastrophic event like the 2007 winter kill, it takes two to three years for abluebird population to regain its former status. Go bluebirds!
Tree Swallows had their own set of problems this year. Swallows are aerial feeders, and the fifth coldest May on record, followed by the wettest June on record, may have been responsible for a 15.7% decrease in production from DSP’s 2007 total. Nonetheless, the park’s boxes housed 100 successful swallow nests that produced 393 fledglings. Using published values describing the diet of Tree Swallows, 100 active nests translate into more than thirty million flying insects consumed while the colony used the park’s nest boxes. Tree Swallows certainly do their part to enhance the camping experience at DSP.
In addition, 28 nests in DSP produced 164 (+49%) House Wrens, and six Tufted Titmice fledged from one nest.
Eleven nest boxes are located at the Alum Creek State Park Office and two pairs of boxes are found off of South Old State Road north of Cheshire Road. Only one pair of bluebirds nested at the park office, but their eggs were infertile. Three clutches totaling 14 eggs showed no embryonic development whatsoever. The female tried to hatch the infertile eggs for many days beyond the 12-14 day incubation period, but to no avail. While this phenomon is not common, in the 41 years of recording data, I have seen it several times before.
Tree Swallow production at ACSP was nearly the same with eight nests producing 32 birds as compared to 31 in 2007. Also, House Wrens fledged seven.
Since 1989, I have used active nests at DSP as props during field trips to teach talented and gifted middle school students participating in the OWjL Academic Camp at Ohio Wesleyan University. Campers live in dormitories and attend one of three one-week sessions in June, where they choose four courses from as many of seventy courses listed under the categories of either “Arts” or “Sciences.” My course is “Bluebird Trail Management.” We visit DSP on Tuesdays, Wednesdays, and Thursdays to inspect nests of swallows, bluebirds, and wrens where we experience nests with eggs and nestlings at different stages of development. Students quickly learn that habitat and nest box location determines the species that uses each nest box.
I must keep precise records in order to plan effective nest visits that are best for learning experiences while respecting the birds’ welfare. We attach leg bands to nestlings representing all three species. We weigh very young nestlings on Tuesdays, and re-weigh the same families on Thursdays to calculate their rate of growth. Almost always, nestlings double their weight in 48 hours, which leads to some very interesting conversations. (We also doubled our weights in two days when we looked very much like the bare, eyeless, squirmy nestlings.)
In addition to my banding permits, I explain the importance of my other federal and state permits to the students. Over the years, I have learned that at least one-third of the students in my course are thinking of becoming veterinarians or considering some other profession that requires interactions with animals. To promote their interest in birds, we conclude the course on Fridays as we construct bluebird nest boxes on campus. Each camper takes a nest box home where the course will continue once they install their handiwork.
For the three one-week sessions in 2008, seven, eight, and ten campers, and three college-aged counselors, experienced Bluebird Trail Management in Delaware State Park.
With the end of the nesting season for Tree Swallows, I report on two nest box grids of 25 and 27 nest boxes, respectively, located along Panhandle and Leonardsburg Roads in the Delaware Wildlife Area which is managed by the Ohio Division of Wildlife. A Tree Swallows nest box grid is made of rows of bluebird nest boxes that crisscross at 25 yard intervals.
Swallows nesting in the wildlife area’s grid boxes raised 251 offspring in 2008. Swallows laid at least one egg in all but one box. Forty-eight (92.3%) nest boxes produced families, and nine productive boxes (18.8%) produced two broods. The average production for successful nests was 4.48 fledglings.
The first swallow egg was laid on April 27 and the last family fledged on August 1, for a typical season of 97 days. Swallows laid 383 eggs, hatched 273 (71.3%), and fledged 251 (65.6%).
Weathermen in Columbus reported that May was the fifth coldest, June was the wettest, and July was the eleventh driest, in recorded history, so swallows were challenged in their attempts to be successful parents. Once eggs hatched, more than nine out of ten nestlings (91.9%) fledged. Most nest failures occurred during the egg laying or incubation periods during May when cooler than normal temperatures grounded flying insects. Aborted nest attempts were followed by second attempts once seasonal temperatures returned.
A male House Sparrow became a serial killer while trying to attract a female at the Leonardsburg Road grid. He killed four swallows in three boxes before a Van Ert sparrow trap made it possible for me to send him to the spirit world.
Tree Swallows nested on seven additional trails that I maintain and monitor in Delaware County. When trail counts are added to the wildlife area’s swallow production, the grand total is 1072 tree swallows fledged in 2008. I list the following locations with their final counts.
|Delaware State Park||393|
|Delaware Wildlife Refuge||251|
|Alum Creek State Park Office||32|
|Alum Creek Prothonotary Warbler Project||22|
|Methodist Theological School in Ohio||54|
|Olentangy Environmental Control Center||170|
|Delaware Golf Club||146|
Since no bluebirds nested within the wildlife area grids this year, I was able to dismantle the nest boxes and PVC predator guards days earlier than in previous years. I stored the grids on my back porch on August 3 and 4. I will return nest boxes to their wetland mounts by March 15, 2009.
While monitoring the birds every nine days, I enjoy walking among the tall grass prairie plants, especially at the Leonardsburg Road Grid where swamp milkweed supports multitudes of carpenter bees and other pollinators. So far, I have never been threatened by the bees even though I bump many of them from their duties as I go about my business.
There is more to bluebirding than bluebirds.