Friday, August 10, 2012

Migrating Kites Tallied at Roosts and Tracked by Satellite

8/10/12: Swallow-tailed Kite 2012 Roost Surveys
We recently completed the 2012 surveys of Swallow-tailed Kite pre-migration roosts in Florida. The good news is that our counts have been consistent the last several years, at least suggesting that there is no apparent decline at this time. We will continue to watch the 5,000 mile migrations of 13 satellite-tracked kites unfold over the next few weeks. Half are already in Latin America, the leader just entering Colombia. The rest remain in the U.S., yet to face the quickly-changing winds and emerging storms of the Gulf of Mexico, Florida Straits, Yucatan Channel, and Caribbean Sea.    

This is the 24th year that ARCI has monitored the pre-migration roosts of Swallow-tailed Kites in Florida.  We began by counting a single aggregation west of Lake Okeechobee that still peaks at over 3,000 birds each year. This roost remains the largest of nine that total nearly 7,000 annually. In most of the 24 years, our surveys have been funded by contributions, not grants. The exception, supported by USFWS, was a collaborative study from 2009 to 2011 by ARCI and partners in six other states (see Programs). Our goal was to refine our monitoring methods and size estimates of the national population.     

In 2011, USFWS provided funding to ARCI and Dr. Jennifer Coulson (Orleans Audubon Society) to deploy GPS-equipped satellite transmitters on adult Swallow-tailed Kites. We tagged birds in five states to identify previously unknown roosts, improve our estimates of survivorship, and identify threats on the South American winter range. Thanks to the GPS fixes, we recently discovered two previously unknown roosts totaling 427 kites. The GPS data also have filled many gaps in ARCI's previous documentation of kite migration, which was based on less sophisticated tracking devices. Over the five years of expected life, this exciting new generation of satellite transmitters will reveal year-round movements and habitat selection of Swallow-tailed Kites at an unprecedented scale.