Fate of the Nightjars?

Explanation: Here's a family of birds found throughout the globe, but for which we have scattered to no data on their population sizes, trends, and threats.

The family of nightjars includes poorwills, nighthawks, pauraques, and others. The main star of this week (above photo) is the Slender-tailed Nightjar, a widespread denizen of central Africa, shown here on a ground-roost at Lake Baringo in the Rift Valley of southern Kenya. This species seems to be secure, but other nightjar species may not be so lucky.

For example, declines have been noted for European Nightjars (Caprimulgus europaeus) and Red-necked Nightjars (C. ruficollis). Several other nightjar species also are listed as decreasing or unknown status by IUCN. In the U.S., Common Nighthawks (Chordeiles minor) and Common Poorwills (Phalaenoptilus nuttallii) no longer seem to be, well, as common as their name suggests, and surveys have been initiated to determine their condition.

The Montane Nightjar (Caprimulgus poliocephalus) -- photographed here at Sinya Wildlife Conservancy in northern Tanzania, east Africa -- seems stable in its range, although there seems to be little actual data on their population size, trend, and productivity.

Above and below is the Fiery-necked Nightjar (Caprimulgus pectoralis), photographed here at night in South Luongwa National Park in Zambia, Africa.

Although essentially nothing is known of survival rates of nightjars in general, this species was studied in southwest Spain (Forero et al. 2001). It was found that, inexplicably, rainfall levels affected survival of females negatively but for males positively. Most likely, some other unidentified environmental factor or behavior was at play.

Information:
Forero, M.G., J.L. Tella, and D. Oro. 2001. Annual survival rates of adult Red-necked Nightjars Caprimulgus ruficollis. Ibis 143(2):273-277.

EPOW - Ecology Picture of the Week