Friday, April 29, 2011

Spring Kettles? Yes!

photo by S.Fogleman

From whence came the notion that Broad-wings don’t travel in kettles in spring migration? I’ve been puzzled by this belief which I’ve encountered several times over the last few days.

Here’s what has been happening in the northeast – specifically New England, upstate New York and southeastern Canada. Weather patterns were such that soaring, thermal-dependent migrants like Broad-winged Hawks were temporarily held up in their northward journey. On April 26, conditions began to improve, with big flights being recorded at places like Ripley (in NY). Perhaps Gil Randell will write about this in a future blog – he was a bit tied up counting and compiling so had to skip his turn in the current blog cycle! Check out for the April 26 counts at Ripley and other NY and Canadian sites.

As weather improvements moved eastward, New England birding listservs began lighting up with reports of Broad-wings on the move “as soon as the sky began to clear” on the 27th. That day had started out with mizzle and fog early on, grey skies, no breeze. That’s when the comments regarding kettles started to hit me. I’d heard this “myth” before. And now reports from numerous birders included such remarks as “never have seen so many Broad-wings in spring migration,” “there were even kettles!” “these hawks [Broadies] don’t form kettles in the spring like they do in fall, so this was amazing!” “I couldn’t believe that I was actually seeing kettles!”

Broad-wings do indeed form kettles during spring migration given good lift conditions. When there’s an elevator going up and you want to go up, you hop on, right? The thing about spring here in this part of the continent is that those birds which managed to survive the perils of the preceding 6 or 7 months comprise only a fraction of what we may have witnessed leaving in September, ergo fewer to speckle the sky in April, ergo smaller kettles by the time they get up here. This is the destination region – many birds are now at or nearly at their breeding territories. Weather patterns here in the spring time tend to produce more turbulence, hence unreliable “elevators.” However, given the right conditions – you bet! Kettles! And Wednesday, the 27th, was just what the hawks needed. Not only Broad-wings, by the way, but numerous birds of other species were on the move. Unfortunately there are no longer any official spring watch sites in NH, but accounts from various locations were posted on NH.Birds, and can probably be found there. Numbers from major counts in NY and Ontario posted to HawkCount were impressive: Braddock Bay 42235, Derby Hill 6319, Grimsby (Beamer) 5291. Were the Broad-wings in kettles? Oh, yes!

As the sky began to clear at my home in central NH (elevation 1200’) 228 hawks of 10 species were counted passing over our little piece of sky for the period of watching 1120 to 1430. Almost all the Broadies were in kettles, or at least saucepans!


  1. You raise a very interesting question: Do fewer Broadwings return in the Spring or do we see fewer in the Spring?

  2. Greater numbers depart in the fall (adults along with young of the year). With mortality resulting from perils encountered during migration and on the wintering grounds fewer birds return to the breeding territories. This is true for all migrant birds, not just Broadwings. Do we see fewer in the spring? If there are fewer to see, we see fewer. Additionally, there are fewer watchers/watches recording the northbound migrants.