Birds can be our connection to the tropics
Our connection to the tropics? You mean places like Brazil, where the Amazon flows? Or Venezuela and Columbia, where dictators rule, jungle armies hide out and illegal drugs are grown? Or maybe Guatemala, where destitute families give up their agrarian lives in hopes of finding a way to the U.S. to escape tyranny and lawlessness?
Yes, those are the places alright, but I’d like to talk here about birds. Tropical birds, that is, that spend most of their lives south of Mexico, but migrate north thousands of miles each spring to partake in the explosion of forest insects to feed themselves and their young in our own neighborhoods, fields, and forests.
We call these birds “neotropical migrants” because they live mostly in the neotropics — meaning New World tropics — but they migrate seasonally to and from temperate North America to breed. I will never forget this term because of the way our congressman once recalled it when asked what issues/problems he would like our research lab near Wellsboro to look into.
“Well,” he said, “there are these neotropical birds in the Allegheny National Forest that are causing some sort of problem,” as if they were invasive species that had to be brought under control. Little did he understand howimportant they are to protecting that forest.
These neotropical migrants that arrive in our forests, parks and back yards in April and May each year are mostly songbirds, birds with a complex vocal apparatus that enables them to produce a rich repertoire of musical sounds. Their songs enrich our lives, but only for part of the year, so we need to enjoy them in spring and summer when they are here.
By August the woods grow almost silent again as many of these same vocal species focus on feeding their young and becoming cryptic to predators. Though neotropical songbirds include many families of birds such as sparrows, buntings and grosbeaks, finches, thrushes, swallows, and vireos, perhaps most notable in terms of variety of species and beauty of plumage (as well as song) are the wood warblers (family Parulidae).
There are some 30 species of wood warblers that breed or migrate through Pennsylvania seasonally. These specialized avian insectivores play a critical role in controlling insect populations in our forests by finding and catching bugs. They do so in a variety of ways: there are gleaners, sallyers, and probers, for example. Distinct levels within the forest are also occupied by specialized species: canopy dwellers, mid-story foragers, and ground-level hunters .
Though many of these songbirds can be observed and heard in our back yards this summer, let’s do our best to keep them coming back to our forests in years to come. Some ways to do this include supporting conservation initiatives that reduce or prevent further fragmentation of large forest tracts (many of these birds are forest-interior birds that reproduce poorly near edges and require unbroken forested tracts).
Preventing window strikes will also save woodland birds. Some local audubon societies have placed methods to do this on their websites. And switching to shade-grown bird-friendly coffee, now present in many stores, will discourage loss of forest canopies in tropical America.
Wood Thrushes have been declining at a rate of 2% per year in our forests since the 1960s — a loss of half their entire population in half a century. The song of this woodland relative of the robin is so beautiful and melodic that I make sure I’m back in Penn’s Woods by the first of May to hear him. You can enjoy these forest songbirds too in nearby state forest or game lands this May through July. Just park the car, walk down a trail and just listen (early or late in the day is best).
Finding them with binoculars will add to the experience. Some of the birds easily found this way are shown in the photos with this article, and I took those photos doing just that. Hunting with a rifle is certainly an acceptable sport in Penn’s Woods, but hunting with a camera is another way to challenge your outdoor skills.
So when you find one or more of these forest gems by ear or by eye this spring/summer, those insectivorous neotropical migrants, think of the tropical forests they live in during our winters and the energy they bring back to our woodlands from the tropics, come spring. And remember that these birds know no political boundaries as we do.
They just want intact forests to live in.
Ross is an ecologist retired from the USGS facility near Wellsboro. He remains active in the local birding community and has traveled extensively throughout the American tropics.