What to watch for in May: Migration Continues!

Here’s the Central Texas bird forecast for the month, courtesy of Travis Audubon. Learn more about Central Texas birds and bird-related events for all ages at travisaudubon.org or by calling 512-300-BIRD. Follow us at www.facebook.com/travisaudubon

Ground Warblers

Warblers are small birds and don’t have much incentive to show themselves during migration. Plus, many are foraging high in the treetops, and can be frustratingly hard to see. Birders look for key characteristics such as presence or absence of wingbars, bill and tail length, and color patterns. Without seeing the full bird they can often identify it, piecing the bird together like a puzzle from several quick views. Listening to its songs or chip notes helps clinch the ID.

Bird watchers who occasionally suffer from “warbler neck” are thankful that not all warblers are found in the high canopy. Some favor the midstory or lower vegetation levels, and the ground level is the habitat niche for others.

Here are three warblers that spend much of their time on the ground. They come through Austin during May, en route to their breeding grounds further north. None of these breed in Texas.

The Ovenbird is large for a warbler, with a short tail and large eyes accentuated by white eye-rings. It has an orange crown patch outlined by dark stripes. Its back is olive brown and its white breast is covered with black streaks. The Ovenbird often cocks its tail up, and it has a jerky gait. Ovenbirds spend most of their time on the ground, foraging in shaded woods. They have a distinctive loud chip which may alert you to start looking, but they are well camouflaged to match leaf litter. Ovenbirds are widely distributed across the forests of North America, and winter in Mexico and Central America. (Appalachian Ovenbirds winter in Florida and the Caribbean.)

An alert Ovenbird- COURTESY: James Giroux

Fun facts:

The Ovenbird gets its name from its dome-shaped nest which resembles a Dutch oven. The female constructs it from the inside, so that its cup nest, side entrance and roof are integrated. Then she decorates it with leaves and twigs.

Its song is a ringing “teacher, teacher, teacher,” increasing in volume, but we don’t hear it much in migration. Instead you might hear a rapid loud chip.

The best way to find one in Austin is to look for a shaded forest floor with lots of leaf litter, then sit, watch and listen. The Nature Viewing Station at Mills Pond Recreation Area in north Austin is one of the better places to try for an Ovenbird, as is Circle Acres adjacent to Roy Guerrero Park.

The Mourning Warbler is a stunning olive green-backed, yellow-bellied bird with a gray hood. The male’s hood is dark gray with a black chest patch. The female’s hood is a pale gray. The adult male has no eye-rings while the adult female may show very thin broken white eye-rings. (There is a western warbler that closely resembles the Mourning, called the MacGillivray’s. It sometimes shows up here in migration and it is mainly distinguished from the Mourning by the presence of broad, short white eye-arcs that really pop.) Mourning Warblers breed in dense thickets in forest clearings, so look for them in similar habitat in migration. They are one of the later warblers to migrate through, since they are coming from lower Central America and northern South America. Some don’t reach their breeding grounds until early June. Mourning Warblers forage for insects from ground level to about six feet, but also eat some fruits. These are fairly skulky birds, but put yourself in the right habitat, and listen for their rolling song.

Female Mourning Warbler – COURTESY: Jane Tillman

Fun facts:

The Mourning Warbler has distinct dialects, sometimes called regiolects. There are four distinct types with unique songs based on geography. Newfoundland and Nova Scotia each have a regiolect. The eastern regiolect, ranges from Manitoba and the Great Lakes states to the Appalachians and West Virginia, and the western regiolect spans western Ontario, the prairie provinces of Canada, and British Columbia. Males recognize the different regiolects, with more antagonism shown to those of their geographic origin.

Mourning Warblers prefer early successional habitat for breeding, so after it matures in seven to ten years they have to look for new sites. Clear cutting and natural forest disturbances like fire and windfall supply this.

Adult Mourning Warblers are known to feign a broken wing to lure predators away from their nest. Can you think of a common shorebird that also uses this broken wing tactic?

The Northern Waterthrush is well-named. During migration you will find it along wooded streams and pond edges where its loud “spwik” call note broadcasts its presence. Then look for a brown bird about six inches long bobbing its tail as it forages along the edges, or flies to a floating log to glean insects. It has a white eyebrow and dense dark streaking on its underparts including its neck. A very closely-related warbler is the Louisiana Waterthrush, but they barely overlap in their summer ranges. The Northern breeds much further north across most of Canada while the Louisiana breeds in the eastern and southern states and even here in Austin. The Northern Waterthrush that migrates farther generally migrates through Austin later in the season – it does not make sense for it to arrive on the breeding ground before the weather supports the foods it depends on.

Northern Waterthrush – COURTESY: James Giroux

Fun facts:

Northern and Louisiana Waterthrush are very similar and will test your bird watching skills. You could say they are a graduate level identification challenge. Take a photo and consult a field guide for help.

Louisiana Waterthrush – COURTESY: James Giroux

Northern Waterthrush prefer standing water in boggy, swampy bogs while Louisiana like rushing streams.

Good places to look for Northern Waterthrush during migration are Circle Acres adjacent to Roy Guerrero, which has standing water. The boggy parts of Mills Pond are also a good spot for them. Louisiana Waterthrush breed along Bull Creek and other streams in the Hill Country.

When to Go Birding during Migration?

If you want to know exactly how many birds might be in the air, night by night, during migration, check BirdCast, a collaborative effort to understand and predict bird movements based on weather radar surveillance. You can even check to see whether birds will be migrating over Austin in low, medium or high densities with the local migration alert feature. Keep in mind that even though a large number of birds might be moving through, they may not stick around the next day. Birds are in a hurry to get to their breeding grounds to get the best territories.

Upcoming Travis Audubon Events Check the Travis Audubon events calendar for details on field trips, classes and other events. Beginners are welcome on all field trips.Get outdoors with a knowledgeable leader and learn more about our beautiful Austin-area birds. Most field trips fill quickly, and most require registration.

Compiled by Travis Audubon volunteer Jane Tillman