Date: 3/18/17 4:30 pm From: Joseph Neal <joeneal...> Subject: CROSSBILLS MAY HAVE NESTED IN OZARKS
Several of us on the Northwest Arkansas Audubon Society field trip this morning saw Red Crossbills near Shores Lake in the Ozark National Forest. The birds were first observed by Bill Beall and Jim Nieting on March 4 and have been found subsequently, more or less in the same area, including today. We had clear looks at three birds this morning. Joan Reynolds and I saw 5-6 in the same area on March 5. On that date, we observed one crossbill feed another. A photo of the bird that was fed shows it is a streaky fledgling. This is supportive of the hypothesis that Red Crossbills nested in the Shores Lake area over winter 2016-2017.
Some unfamiliar with crossbill nesting behavior are a little shocked about the hypothesis that crossbills may have nested here, with at least one fledgling on the wing by at least early March. In terms of Arkansas, it is pretty unusual, but then we are fortunate that Bill Beall has been birding the area for many years and has many other crossbill records. One difference this time is that we managed to photograph birds because they are close to the highway. Bill and Jim Nieting let us know right away when they observed them.
Data for Red Crossbill in the Cornell Lab of Ornithology Birds of North America indicates food as the most important factor influencing timing of nesting. “Egg dates in North America from mid-Dec to early Sep …” Also, “Red Crossbill's annual breeding cycle is apparently regulated by photoperiod, with opportunistic responses to food supply and social factors superimposed on this cycle.”
Shortleaf Pine forest where we are seeing these crossbills has been thinned. Tree stands are now open and park-like, dominated by mature Shortleaf Pines, with many mature trees heavy with pine cones – ideal for crossbills. The Forest Service manages this way because it is suitable for natural reproduction of pines in managed forests and secondarily because it produces high-quality natural habitat for all kinds of native wildlife, both plant and animal. It may very well have fostered nesting by Red Crossbills in the state, too.
Red Crossbill populations are divided by call types. These different call types may reflect separate species under the umbrella name Red Crossbill. UA-Fayetteville graduate students Anant Deshwal and Pooja Panwar collected sound files from these birds on March 8, edited the files, which were then sent to Matt Young at Cornell. Hopefully we have enough data that Young can identify these crossbills to call type.
More than 20 years ago, Bill Holiman, now Chief of Research at Arkansas Natural heritage Commission, encouraged me to record crossbill call types for birds I saw and heard in the Ouachita NF. I didn’t follow through at the time. Subsequently, I have managed to record birds in northwest Arkansas. With help from Matt Young, we have identified three call types from crossbills in Arkansas. The birds currently in the Ozark NF would be the first identified that may have nested here.