Over the past few weeks here at Mad Island, the weather has been sunny and hot, with mild south winds bringing warmth and humidity. This weather pattern leads to low capture rates in our nets, as many birds use the south winds to bypass the scrubby coastal woodlands and head for the more extensive deciduous forests further north. With migration at its peak, however, we have been capturing a diversity of birds despite the weather, and seeing new species arriving to the refuge almost daily.
Some notable first captures have been Dickcissel, Philadelphia Vireo, and Blackpoll Warbler. The Dickcissels arrived suddenly, with huge numbers appearing within days of our first sighting. Flocks numbering in the thousands have been seen, and smaller groups of these gregarious birds are everywhere on refuge. Dickcissels breed in grassy habitat throughout the central part of the continent, so Texas might represent the endpoint of the migration for some individuals.
In contrast, the Philadelphia Vireos and Blackpoll Warblers we encountered still have a very long distance to cover. Some of the Blackpolls will even travel all the way to northern Alaska to breed, after spending the winter in northern South America. This massive journey is undertaken twice a year by a bird that weighs about 12 grams. That's close to the same mass as two quarters!
Joining these new arrivals are continuing numbers of Swainson's and Gray-cheeked Thrushes, Indigo and Painted Buntings, Orchard and Baltimore Orioles, and the ever present Gray Catbirds. We were also surprised to capture a Green Heron!
Evenings at Mad Island are now filled with the sounds of Common Nighthawks displaying and the resident Painted Buntings singing on territories. Migration is still at its peak, but summer is on the way.
There are only a few short weeks left for this years project, and several species are still notably absent. So we are looking closely at the changing winds in the forecast, and hoping for a strong wave of migrants in the coming days.
Birds captured: 1678
Species captured: 79
Species observed: 222
Ticks collected: 72