I suppose my first post should include a bit of an explanation into the name of my blog. The word comes from German, and is a combination of Zug (move, migration) and Unruhe (anxiety, restlessness). It describes the instinctive restlessness that migratory birds experience before the onset of migration. It's often characterized by restlessness, changes in sleep pattern and practice flights in the direction of intended migration.
It seems a particularly apt title to the blog of a seasonal field biologist, though I suppose I'd fall more under the category of nomadic rather than truly migratory, since I don't return to the same area. My wanderings are largely tied to changing of the season, as when the birds I'm studying leave it's time for me to move on and find a new job.
My current employment has me gathering data on what has been described as the greatest migration of carnivores in the world; fall hawk migration. Working with the New Jersey Audubon Society, I am carrying on a long-standing tradition of recording migrating raptors, this being the 54th year of the Montclair Hawk Watch. The 2nd oldest hawk watch in the country, and indeed, the world, Montclair, NJ is an unlikely location for a hawk watch. Surrounded by million dollar homes and suburban development in all directions sits the NJAS's smallest sanctuary, a gravel covered platform barely an acre in size is all that's needed to view the over 10,000 hawks recorded here on average.
This week is a special time in hawk watching, the big Broad-winged Hawk push. Soon, with the next big cold front, thousands of Broad-wings will simultaneously feel the urge to migrate culminate when the right conditions are present. Good winds out of the north to push them on their journey south, a sunny day to heat the land and create those rising pockets of warm air called thermals that will drastically reduce the effort needed to gain lift. Indeed, on a good day, the hawks barely need to flap to stay aloft, instead rely on that rising air to push them upwards, then sailing down towards the next thermal with only a few flaps to steady them. On a good day, several thousand Broad-wings will be seen from the ridge moving by in groups called kettles, ranging in size from dozens to hundreds. As the first birds to reach the top of the column of rising air peal off and head south, the appearance is of a kettle boiling over and spilling out, a river of raptors being carried along on currents of air.
It's a spectacular sight that one has to see to appreciate, occurring every year right over our heads, unnoticed and unremarked by all but a few.
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