Monday, September 22, 2014

Riding the coastline, lifting on wind

Three of our satellite-tracked Swallow-tailed Kites made it to Brazil!  Their GPS data indicate that Day and Palmetto have almost caught up to MIA, who has been far ahead of the other migrants since leaving Florida on 30 July. Two more of our tagged kites, Gulf Hammock and Bluff, are in Peru. Pace is making his way through Panama and PearlMS has passed overland through eastern Mexico.

Tracks of seven tagged Swallow-tailed Kites on their southbound migration from 7 Jul - 9 Sept 2014
Raptors often follow coastlines and mountain ranges during migration, probably as an aid to navigation, but also to exploit the lift produced when winds are deflected upward by ridges. 

Satellite-tracking reveals how Swallow-tailed Kites use coastlines and mountain ranges as migrational aids.

These images show the tracks of six tagged Swallow-tailed Kites moving south along the coastal plain of southern Costa Rica and northern Panama. Note how close their tracks are as they parallel the nearby coast, and how the kites make use of the coastal mountain range to remain aloft using as little energy as possible.  

Can you imagine how many other migrating Swallow-tailed Kites and other species of birds are using these areas?  We hope our tracking information can be used by governments and conservation groups to help protect these valuable migration corridors and to keep them safe for the countless numbers of birds that rely on them each year.