Female Common Nighthawk (Chordeiles minor) incubating eggs
This video shows the rapid throat movements (gular fluttering) in the nighthawk's throat that help her stay relatively cool in the heat of the day while incubating her eggs. Lesser nighthawks (Chordeiles acutipennis) have apparently been observed sustaining this thermoregulatory behavior for eight hours a day on very hot days!
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Common Nighthawk (Chordeiles minor) hatchling
Common Nighthawk (Chordeiles minor) Fledgling
Female Chuck-will's-widow (Caprimulgus carolinensis) incubating eggs
Chuck-will's-widow doing broken wing display and gaping when I approached her eggs
Chuck-will's-widow (Caprimulgus carolinensis) fledgling