Low Light Intensities Some birds sing even at low light intensities Even the evening song of nightingales, to which the Robin is distantly related, can trigger the bird to join in the singing. A bird will suddenly burst into song whenever loud noise is heard, such as fireworks, thunder, earthquakes, or even a sudden shaking of a nest. In addition to light, some other triggers can cause robins and other birds to sing at night. Early morning sunlight trigger the dawn chorus A dawn chorus occurs when birds wake up without enough light to feed, so they sing instead. The sunset chorus follows the same pattern, but in reverse. The dawn chorus is usually led by robins and redstarts, with sparrows and many finches joining in at the end. Marisa Mecke is an environmental journalist.Expert Tip: Nocturnal or diurnal birds follow daily cycles of light and dark.Įarly morning sunlight and the bird’s internal clock trigger the dawn chorus. "They're the best part of the night," Ramos said. They'll also be setting up traps to study the insects in the area to better understand chuck-will's-widows' food intake. She, Rushing and their fellow researchers will be surveying, banding and tagging chuck-will's-widows, locating nests and hopefully learning more about how chucks rear their young.
She's on the ground floor for this new, baseline information on chuck's whereabouts that scientists have never known before.Įven if last summer's tagged chucks don't return, there's other work Ramos is looking forward to during the upcoming nights in coastal Georgia. They've taken bets on where they think the chucks have gone. "We only tagged six (last year), but we're really hoping that at least one or two come back," Ramos said. If the bird doesn't come back, their whereabouts during migration remain a mystery. Rushing's predecessor, Bob Cooper, had nights in Clarke County where he would count 40 or 50 nightjars, but these days Rushing said you'd be lucky to hear one or two on that same route. Surveys tailored specifically for nightjars also indicate a decreasing population.Īnd lastly, Rushing said that anecdotally people who used to hear chuck-will's-widows don't hear them nearly as much anymore. It isn't the best equipped to detect nightjars, Rushing said, but the survey has been consistently conducted using the same methods over time and can give a decent picture of relative decline. In that survey, volunteers drive a set route early in the morning and stop each half mile to count all the birds they see or hear. First, the Breeding Bird Survey - a continental-scale monitoring program that's been conducted since the late 1960s - has indicated a relative decline. There are three ways researchers know this, Rushing said. Throughout the spring they will sweep up the Piedmont, and after nesting and reproducing throughout the summer they will fly south for the winter.Īlthough researchers don't know a lot about chucks, they do know there are fewer of them. In Georgia, the chuck-will's-widow is a native summer resident that will begin arriving on the coast in the next few weeks. Their call can be most frequently heard at dusk, especially when the moon is full, but they're easy to confuse with a close relative, the more well-known whip-poor-will. "If you squint a little bit," Rushing said, they sound like they're saying their name. They are nearly impossible to find unless they are making their calls.
Moreover, where many owl species vocalize or are somewhat active during the day, chuck-will's-widows are only active at dusk and during the night. Unlike other nocturnal birds native to Georgia, like barred owls, the chuck-will's-widow migrates south for much of the year. Part of why researchers know so little about this bird is that they're simply hard to observe. "The irony is they're so charismatic, but you rarely ever get to actually encounter them," Rushing said.
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