As the season continues to progress with changing weather and shorter days at the Montclair Hawkwatch, the assemblage of migrants and local birds has also shifted. Temperature has stayed consistently below 60 degrees, and rain has been a bit more regular. Strong gusts of wind that occurred throughout the day on the 17th were significant enough to warrant a local high wind warning, and they seemed to deter birds from taking flight. The few brazen hawks that did fly over during these conditions were tossed around by the wind dramatically, and turkey vultures that flew by teetered in the air in a much more pronounced fashion that usual, with several almost appearing to have lost control. The weather this day was unusual, although many days this week were breezy to a lesser degree.
With the cooler weather, butterfly and dragonfly numbers have dropped. A few straggler monarchs are still migrating over, but the species is no longer a daily site. By this point in the season, Broad-winged Hawk migration has ceased over the platform as well. I did not count any this week. However, a few more Red-shouldered Hawks and Red-tailed Hawks are beginning to trickle southward, effectively filling in the gap of migrant Buteos created by the absence of Broad-wings. Unlike the Broad-winged Hawks, Red-shouldered Hawks and Red-tails are partial migrants, and with less distance required to cover on their southward journey, they can afford to begin migrating later in the autumn.
Turkey Vultures, another partial migrant, were the highest-numbering birds tallied this week. Most spotted above the platform traveled by gliding in linear groups, and by circling upwards in thermals. Kettling in thermals and southward streaming are easily observable migrant behaviors, but local vultures still abound, so individuals of this species require extra observation to infer whether they are actual migrants.
On Sunday the 13th, six migrating Bald Eagles passed overhead throughout the course of the day; four of which were in full adult plumage. The local eagles that spend time near Cedar Grove Reservoir often make an appearance within view of the platform, but to have six migrants in a day was both welcome and noteworthy. Other notable birds I saw this week were an Eastern Towhee and a Vesper Sparrow, which both appeared briefly on the platform out of nearby vegetation before disappearing under cover again. These were the first recorded sightings of these species this season. Heralding the change in seasons, two also Slate-colored Juncos stopped by the hawkwatch on the 13th to forage. I have not seen any since then, but as the weeks pass this common wintertime bird will likely show up again.
Happy Birding!
David Rosenbaum
