Birds of the Month | April 7, 2018
 The other day I was having breakfast at that wonderful Gulf Drive Cafe on Anna Maria Island, when I saw a single bright yellowish bird with a rusty head and a broad eyebrow hopping around in the sand under the tables. It was of course a Palm Warbler, a bird we see more-or-less everywhere we go during the winter months in Florida. The difference was that this little guy was getting into its breeding plumage and a more attractive bird it would be difficult to find. Its lines were crisp, its throat and under tail coverts were bright yellow, and its wide, prominent super cilium gave it a most handsome look.
This extremely common winter visitor throughout Florida, present from September/October to May, can be found in almost any habitat, from open hardwood and pine forests, marshes, prairies, coastal strands, cultivated fields, roadsides, parks and yards. However, I believe this was the first time I’d seen a Palm Warbler stealing crumbs, sparrow-style, from under cafe tables!
In winter any dull-colored brownish bird that bobs its tail continually, foraging on the ground, is likely to be a Palm Warbler (Pumper). This can be confirmed by its most familiar call, a weak ‘tsip’. In winter it tends to associate with other species of warbler, most often, the Yellow-rumped. These two warblers are so frequently seen that it is easy to take them for granted. However when they arrive in September, it’s always a joy to see them. On winter days when not much is around, they enliven our birding walks. And when we see them, there is always the hope that other warblers may be keeping company, maybe a Yellow-throated Warbler, a Prairie or even a Pine.
The Yellow-rumped Warbler, alias, Rumper or Butterbutt, also brightens things up for us during a Florida winter. Its name is wholly appropriate as under the right circumstances its bright yellow rump stands out like a beacon. Although often seen in the same habitat as the Palm Warbler, the Yellow-rumped Warbler usually feeds in trees and bushes, where its call notes (louder and crisper than the Pumpers’) can be clearly heard even when the birds are tantalizingly hard to see.
The species’ departure date is generally the first week in June and they will not return until October, and according to ‘The Birdlife of Florida’ by Anderson and Stevenson this bird makes up 85-95% of all wintering warblers. And of course the bird we most frequently see is the sub-species ‘Myrtle’, Dendroica coronata.
For a long time the debate about whether the Yellow-rumped Warbler would be split again raged on. For most of the last century it was considered to be two species, the Myrtle Warbler of the east, and the Audubon’s Warbler of the west. But in 1973 they were lumped together on the basis that the two species hybridized in a narrow zone in western Canada. Since then extensive DNA evidence emerged suggesting that Myrtle’s and Audubon’s are indeed separate species, and so is a third, isolated form known as Goldman’s Warbler that is almost entirely restricted to Guatemala. A fourth form known as the Black-fronted Warbler lives in the mountains of Mexico but its species status was more debatable. The birding world held its breath for a long time while the debate raged but finally the American Ornithological Society (AOS) in 2017 voted against the proposal to split by a vote of 7-4 until further genetic analysis and determination of the extent of interbreeding in the subspecies’ contact zones. However if I go to Guatemala or Mexico I might just try to see these subspecies in anticipation of a possible ‘armchair twitch’ in years to come.
Meanwhile let’s enjoy and appreciate our Pumpers and Rumpers for the next few months and watch them change into their beautiful breeding plumage. They’ll soon be gone till the Autumn!