The Nature Writers of Texas

The best nature writing from the newspaper, magazine, blog and book authors of the Lone Star State . . .

Sunday, July 29, 2007

Male Hummingbirds Are Early Migrants
by Ro Wauer

It seems impossible that some of the southbound fall migrant birds are already arriving in south Texas. Only a few short weeks ago we were watching the hordes of northbound migrants that were passing through our area en route to their nesting grounds to the north. And now, barely four to six weeks later, some of those same birds are heading south to their wintering grounds in Mexico and Central America. Although the majority of the neotropical migrants are still feeding young far to the north, a few, such as several of the male hummingbirds and a number of shorebirds, are already back in Texas.

It has been said, and truthfully so, that male hummingbirds are little more than brightly colored "promiscuous rakes." They have little or no home life. In spring they migrate north to ancestral breeding grounds where they establish territories, which they may defend against other hummers to their death, performing fascinating aerial displays to attract the ladies, mating whenever the opportunity occurs, and heading south as soon as all the available females are on a nest.

It is the female hummingbird that selects the nest site, builds the nest, incubates the two or three eggs, and feeds the nestlings. Male hummers are long gone halfway through the nesting season. They search out lush mountain meadows with lots of wildflowers, where they usually remain until late summer or fall. Sometimes male hummers passing through South Texas will find suitable conditions to keep them in one place for a few weeks or, rarely, into fall and even all winter.

Shorebirds share similar behavior. Many of the shorebirds that we observed along the South Texas coastline in March and April continued northward to northern Canada or Alaska. Although some shorebirds are like hummingbirds, with males departing their breeding grounds soon after mating, others are caring parents. But the great number of shorebirds that utilize the northern tundra to nest experience a short summer and extremely long days that permit a faster nesting cycle. Many nestlings are feed twenty hours a day, and many of the young are precocial (capable of a high degree of independent activity from birth): they follow their parents about, feeding on the abundant tundra insects within hours of hatching.

The long days and abundant food leads to a very swift completion of their nesting cycle. So the coastal wetlands in Texas, like a narrow part of a North American hourglass, experience great numbers of southbound shorebirds by mid-summer. And wherever masses of shorebirds are found, raptors are not far behind.

Of the hundreds of post-nesting birds that can be found in South Texas in late July and early August, my personal favorite is the rufous hummingbird. Its arrival somehow represents a very distinct change in the characters that utilize our yards. The summer resident ruby-throated, black-chinned, and the larger buff-bellied hummingbirds are less territorial and aggressive. Only the much larger buff-bellied hummer dominates a male rufous hummer. But it is the rufous hummingbird that controls the choice patches of flowers and a favorite feeder that were earlier utilized by the resident ruby-throat and black-chinned hummingbirds. Even in September, when the yard can be filled with 50 to 100 southbound ruby-throated hummers, the one or two rufous hummers that have managed to stay are dominant. Rufous males are pugnacious characters with a personality all of their own!


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