Tuesday, December 20, 2011

Merlins

A female Merlin, Falco columbarius, sits high atop a dead snag in Green Lawn Cemetery on Columbus, Ohio's south side. Bernie Master and I were canvassing the cemetery yesterday, doing our part to tally birds for the Columbus Christmas Bird Count.

This is now the 5th or 6th winter in a row that Merlins have returned to Green Lawn. They're generally a snap to find; just patrol the area immediately south of the bridge towards the cemetery's southwest corner, and you should spot one or more of the birds teed up on the most prominent dead snags.

I glanced over at another, more distant snag and there was yet another Merlin, an adult male, or tiercel.

And then, wham! An immature tiercel (falcon-speak for males) shot in like a cannonball and mixed it up a bit with the other male. So, three different Merlins were all in sight simultaneously - the largest number of birds that I have yet seen at Green Lawn. One must wonder if this is a family unit, and if so, where they nested. I believe it is just a matter of time before this species is found nesting in the cemetery.

One of the males speeds off, looking rather nighthawkesque. Merlins are the ultimate "bird hawks", flying down and whacking songbirds with ease. You would not want to be a cardinal or junco and find yourself in the sights of one of these sleek avian missiles.

I find the personalities of Merlins interesting and charismatic. The adult female will sit like a queen atop her snag, seemingly looking with great disdain at all that is beneath her. You can walk right under the tree, and she'll scarcely even bother to cast a glance your way. Mere ground-bound humans are not worth the bother of of even a sideways look. At one point, one of the males returned from a foray, and couldn't resist roaring in low over the perched female, nearly whacking her in the head. She didn't even flinch, or even acknowledge his presence. Total cool.

Courtesy of the National Audubon Society's immense treasure trove of over a century's worth of Christmas Bird Count data, I was able to assemble some instructive charts. The one above depicts the last 50 years of CBC data for Merlin from the entire U.S. A steady upwards climb - Merlins are doing well, and we see this success reflected in the number of birds that are reported each year in Ohio.


Here's the last 50 years of CBC data of Merlin in Ohio. Some prominent peaks and valleys, but a steady and rather dramatic upwards surge. It'll be interesting to see how many are found on statewide CBC's this winter.

Photo: Dr. Bernard Master

Bernie and I were quite pleased to find this stunning male American Kestrel, Falco sparverius, mousing in a large open field near the new police impoundment lot on the south side. These little falcons are increasingly hard to find, especially in the Columbus area, where development has eaten up much of the kestrel-friendly countryside.

Photo: Dr. Bernard Master

In short order, the male's mate appeared and joined him in hunting. Hopefully this is a local pair and is nesting nearby. We found another Merlin not far from where these kestrels were hunting, for a total of four. And only two American Kestrels. Until very recently, I would never have predicted that the day would come when it would be easier to find Merlins than it would American Kestrels on this CBC.

American Kestrels are not doing well. This chart shows the 50-year trend from CBC's nationwide.

Here's the graph of the last 50 years of kestrel numbers from all Ohio CBC's. Again, not encouraging. The counts at the beginning of the graph, which date to the early 1960's, are about the same as recent years. The early data may reflect a lack of birder coverage, though - there were fewer counts and fewer people out conducting counts back then. Last year, a total of 819 kestrels were reported from all Ohio CBC's. The annual average over the last decade was 963 birds. The annual average of the decade prior to that - 1991 - 2001 - was 1,342 kestrels, or 40% more birds than were reported on last year's CBC's.

This graph depicts the last 50 years of kestrel CBC data from the Columbus count. A real nosedive here, and not surprising given how much of the open meadow and field habitat has been lost in this area. Habitat loss, in tandem with much "cleaner" agricultural practices are certainly one of the great factors that is adversely impacting kestrels. Some people think that the boom in Cooper's Hawks is also an issue, as these accipiters will prey on kestrels. Another pinch point for kestrels is the availability of suitable nest holes. They're cavity nesters, and in general good holes are probably becoming harder to find and the competition for them from other cavity-nesters is fierce.

4 comments:

Janet Creamer Martin said...

Three merlins at once, very cool!

Jim McCormac said...

Steve Lauer, longtime raptor researcher in NW Ohio, sent along the following interesting comment:

Jim, I read with interest your blog about the Merlins in Columbus (amazing stuff!) and the status of American Kestrels. My son and I participated in the Rudolph, OH CBC on Saturday and had seven raptor species (RTHA, COHA, NOHA, BAEA, PEFA, EASO, GHOW and SEOW) and no AMKE! Back in the mid-1970s Tom Bartlett, Jim Coffman (and son) and I did winter raptor surveys and banding in Seneca Co. It was rare that a couple of hours in the field didn't yield a dozen or more AMKE. More recently Metroparks of the Toledo Area volunteers have been conducting the Oak Openings breeding raptor survey. While we don't have complete area coverage the low number of identified AMKE nesting pairs in suitable habitat is shocking. I agree with all three likely causes for their dropoff. While our Seneca Co surveys were better suited for finding open habitat species it was rare that we saw a COHA (perhaps a handlful in an entire winter). Now it's rare to be in the field for a few hours and not see one. Best wishes for a happy holidays! Regards, Steve Lauer
..

Rick said...

I have also noticed a decline Kestrels,when driving you could always see them perched on the lines. I live east of Dawes in Licking county,going west on our road about 1.5 miles from home,there is always at least one of a pair and then another 2 mi NE another pair. What do we attribute the increase in coopers hawk and do they catch prey on wing?

Jan said...

I know all I read talks of declining kestrals, but here in central Indiana, I see at least 3 or 4 each day on my usual drive to work and 4 to 12 on any given drive into the nearest big town. Although I love all raptors, Kestrals are my favorites. We have had several nest on our small property throughout the past 20 years.

Love your blog by the way. Always informative and entertaining.