Meet the Thrush Family

Migration has been underway here in the midwest with the peak more-or-less beginning yesterday.  Many species of birds migrate twice a year, in the spring and fall. Birds migrate to their summer territories to breed and take advantage of the long daylight hours for foraging or hunting. In the fall, when their food resources are low or exhausted, most birds will switch their diets as they migrate to their winter territories. For example, the Swainson's Hawk will eat mammals during the summer, but switch to insects during the winter.

At the Bird Sanctuary, mist netting during the migration times is almost better than Christmas. It is during these small time frames during the year that we catch birds that spend neither the summer or winter in our neck of the woods but use our part of the region as a rest stop.

We've been mist netting daily this week to take advantage of fall migration. While we have caught a small number of warblers, most of the birds that have found their way into our nets have been the thrushes.

The thrush family includes the American Robin, Eastern Bluebird, Gray-cheeked Thrush, Hermit Thrush, Swainson's Thrush, Veery and Wood Thrush.  The majority of the birds caught have been  Robins and Swainson's Thrush with a few Wood Thrush as well. Today we caught one Gray-cheeked Thrush.

While each thrush species has their own unique habits (more on that later), the Thrush Family (or Turdidae family) have several characteristics in common. The Turdidae family is found worldwide on all the continents and even a few islands. These birds are ground feeders and eat mainly insects and worms during the breeding season, but switch to berries during the winter. Their nests are typically composed of twigs, grasses, weeds and placed high (up to 50 feet)  up in a tree or shrub.

The American Robin (Turdus migratorius) is undoubtedly one of the most well known birds of the Turdidae family that live in North America. These birds live in a wide range of habitats, including deciduous forests, suburbs, open fields and parks. They are short distant migrants, flying only for a few hours during the day, with many inhabiting the southern U.S. during the winter months.  Robins congregate in large, noisy flocks during the winter and it is not uncommon to see these flocks foraging for food. The berries of Eastern Red Cedar Trees are a favorite of the Robins, and consequently, this bird plays a large part in the seed dispersal of this tree (seed, complete with fertilizer! You know what I'm talking about...)

The Gray-cheeked Thrush (Catharus minimus), Hermit Thrush (Catharus guttatus ) Swainson's Thrush (Catharus ustulatus) ,Veery (Catharus fuscescens) and Wood Thrush (Hylocichla mustelina) are often called the "spotted thrushes" and have several characteristics in common.  These thrushes are long distant migrants, flying primarily at night and stopping at dawn to rest and refuel. They inhabit forests and woodlands during the summer. They eat insects and worms during the summer and show a strong preference for woodland fruits that are rich in lipids when they switch their diet in the fall. Incidentally the spotted thrushes are important seed dispersers of their favorite woodland plants, such as the Virginia Creeper, Black Tupelo, Spicebush and the Dogwoods.

We seem to catch more of the Gray-cheeked Thrush during spring migration, although we have a few more days remaining in our fall migration session for their numbers to catch up to the others. These birds winter in the rain forests of South America and are primarily arctic breeders, spending their summer up in Alaska, the Northwest Territories of Canada, Quebec, Labrador and Newfoundland.

We haven't caught a Hermit Thrush yet this fall, but we have caught stragglers in past fall migrations and usually early on in our mist netting season, in April and the first couple of weeks in May.  These birds winter in the southern United States, along the coast of California and all throughout Mexico. They breed in the western US and all of Canada. Unlike the other thrushes, the Hermit Thrush has a rusty red tail, making it easier to tell them apart from the other Thrush species in the field.

The Swainson's Thrush is the bird species that dominates our nets during the spring and fall migration sessions. This is another arctic nester that breeds in Alaska, all across Canada, Labrador and Newfoundland and winters in Central Mexico, Northern Argentina and Paraguay. The eye ring is the field marker for this bird, although it can be difficult to see if looking at this bird through a pair of binoculars. The easiest way to differentiate the thrushes is to listen to their songs.

The Veery is a rare treat for us in the spring. This thrush breeds in lower Canada as well as the north and northeastern part of the US. They winter down in Central American and the northern portion of South America. This is the least spotted of the thrushes.

The Wood Thrush is the bird found here in our neck of the woods, calling the Midwest and the eastern portion of the US home during the summer. They fly down to Central America and northern South America for winter. This species will return to the same wintering site every year and defend it as they would their breeding territory.The Wood Thrush is nearly the size of a Robin and has beautiful rust red and orange feathers.

There are many more Thrushes in this family, 18 species that breed in the United States, but these are the family members that pay us a visit at least once a year.