Friday, December 28, 2007

Ringing in the New Year


The woods are never completely silent. On cold winter days, you won’t hear buzzes or clicks of insects, or the flute-like song of a wood thrush… but you can hear dried leaves rustling in the wind, water flowing downstream, woodpecker taps and calls, and warbler songs. That’s right. Warbler songs.

You see, bird vocalizations can be categorized as ‘songs’ or ‘calls.’ Songs are almost exclusively performed by the males to establish and maintain territories for breeding. The songs function to simultaneously ward off competitors and attract mates. Calls are simple notes or phrases uttered by males and females to communicate the availability of food, presence of predators, or relative distance from the receiver. Since true bird songs are reserved for breeding season activities, even year-round residents have nothing to sing about in the winter months. Or so you would think.

Pine Warblers set up their territories, mate and breed earlier than most other birds in the forest. In Louisiana, they start singing in the winter, and are nesting by the middle of March. So, on a sunny New Year’s Day at Walter B. Jacobs Memorial Nature Park, the forest rings with the tremulous trills of male Pine Warblers singing in the canopy.

Listen to the Pine Warbler:
Find good information about the Pine Warbler:
http://www.fs.fed.us/conf/birds/Pine_Warbler_MIS_New_Plan.pdf
conserveonline.org/docs/2001/05/piwa.doc
http://www.birds.cornell.edu/AllAboutBirds/BirdGuide/Pine_Warbler_dtl.html

Thursday, December 20, 2007

Peepers in December


The breeding song of the Spring Peeper heralds the spring… in Vermont! Here in Louisiana, peepers fill the December night with song. Just as the deciduous trees close up shop for the year and the wintering birds arrive, cold autumn rains revive the vernal ponds and the peepers begin their chorus.


Almost always heard and not seen, these diminutive frogs are only about the size of a nickel. They spend their days sleeping under logs and in leaf litter on the forest floor. They awake in darkness, and spend their nights eating ants, beetles, flies, spiders… whatever’s available… whatever fits in their mouths. Their cryptic coloration affords them some protection. Still, many fall victim to salamanders, snakes, owls, and larger frogs.


Those that live long enough (3 years) will congregate in the temporary ponds. The males establish small territories and call. The louder, faster callers succeed in attracting females for momentary trysts. Fertilized females then deposit their eggs – one at a time – under vegetation and debris on the bottom of the ponds. Each female lays 900 or so eggs before retiring to higher ground. In four months, her offspring – whom she will never know – join her on the forest floor.

Where will the peepers live when the forest is gone? Where will they breed when their habitat is commandeered for a housing development, and their ponds are filled with soil? Those that inhabit protected areas like the 160 acres of Walter B. Jacobs Memorial Nature Park may not have to find out.