Tuesday, September 16, 2008

Get thee to a hawkwatch

If you have even a slight curiosity about hawkwatching, tomorrow, Thursday and probably Friday are likely to be prime days. We are approaching the peak of the Broad-winged Hawk flight, a small soarer that is one of the few raptor species that likes to fly in a group. On a good day, you can see thousands here in the east. On a good day in the midwest around the Great Lakes, you could see tens of thousands on a single day. On a good day in Texas, you might see 100,000 thousand of them.

These crow-sized hawks are not the world's best fliers, despite their twice yearly migration down into central Mexico. They like to fly the easy way. They like to ride thermals created by warm pockets of air. They don't like much wind, not even a tail wind. The wind breaks up their thermals. So these birds circle and circle, gaining altitude with each circle. When they reach the top of the thermal, they peel out in single file and soar to the next thermal.

For the eastern birds, their route takes them southwest, and they are forever gliding slightly off course, only to readjust their route with every thermal. As a result of this constant readjustment, broadwings can also be notoriously difficult to predict, both as to their exact timing and their location. Certain places are more likely to see large concentrations than others, though even a non-descript cow pasture has the potential to be a broadwing hotspot if the winds take them over it.

Roundtop is not the best broadwing spot in the world, but sometimes and in some years, it has been spectacular. Today I saw 8 late in the day, in an hour's watching. Tomorrow, I hope to spend most of the day on the mountain, hoping that this will be the year I see thousands here. Better broadwing spots in this area are Hawk Mountain and Waggoner's Gap, usually. If you're not a regular hawkwatcher, I recommend either of those spots, or one of the other 30-40 hawkwatch sites in this state alone. Check the Hawk Migration Association of North America Web site (www.hmana.org) for a site near you. Maybe I'll see you on a mountaintop sometime this season.


MojoMan said...

What's the best time of day? I'd love to see a kettle of broadwings!

Carolyn H said...

mojoman: Hawks tend not to be early risers, unlike warblers, so you don't have to get up early. Kettles appear when the air is warm enough for thermals. That said, the "best" kettle in my mind is one that isn't 24,000 feet overhead. So between 9-noon will likely give you the best views until around 3-4 p.m. The kettles will still be flying in the mid-afternoon, but they are very high then.

Carolyn H.

MojoMan said...

Thanks for the information! Laura at http://somewhereinnj.blogspot.com/2008/09/skywatching-for-hawks.html also wrote about the problems of seeing hawks soaring so high.

Ruth said...

How interesting it would be to see all those hawks. I love the photo!