Animals often use vocalizations to warn of nearby danger to others. While this information is generally intended for members of the same species, other species can eavesdrop on the warnings to use the information for their own benefit. Sentinels are animals that have warning calls so widely understood by others that those other species will form groups with them, relying on the sentinels to provide warnings for danger.

Researchers are realizing that animal communication is more complicated than previously thought, and that the information animals share in their vocalizations can be complex. For example, some animals produce calls that warn of specific dangers in the environment, such as a predator, and these calls can even contain information about the type of predator (e.g. flying vs ground predator). These calls are known as referential calls.

Students at the University of Illinois Urbana-Champaign once again hosted “Owl Night,” a public outreach event where people of all ages can learn about owl behavior and ecology, and if they’re lucky, see an owl up close. Owl Night takes place on two separate nights: November 1st at Kennekuk County Park, and November 8th at Homer Lake. At Owl Night, participants can learn about owls through a series of hands-on activities, including dissection of owl pellets, examination of owl feathers under a microscope, tracking owls by hand using radiotelemetry, and more!

Yellow warblers are hosts to brood parasitic brown-headed cowbirds, which rely on other species to raise their offspring. Warblers use referential “seet” calls to warn female warblers specifically of the brood parasitic brown-headed cowbirds that may try to lay eggs in their nests. When exposed to experimental playbacks of seet calls one day, female warblers were more vigilant the next morning, researchers report in the current issue of the journal Biology Letters.

Dozens of online videos document an unusual behavior among tufted titmice and their closest bird kin. A bird will land on an unsuspecting mammal and, cautiously and stealthily, pluck out some of its hair.

Some birds lay their eggs in the nests of other bird species and let the host parents raise their young. A new study finds that in times of environmental flux, these brood parasites "diversify their portfolios," minimizing the risks of their unorthodox lifestyle by increasing the number and variety of hosts they select as adoptive parents.

Brown-headed cowbirds show a bias in the sex ratio of their offspring depending on the time of the breeding season, researchers report in a new study. More female than male offspring hatch early in the breeding season in May, and more male hatchlings emerge in July.

Cowbirds are brood parasites: They lay their eggs in the nests of other birds and let those birds raise their young. Prothonotary warblers are a common host of cowbirds.

They say it takes a village to raise a child. But if you are a cowbird, left by your parents to be hatched and raised in the nest of unwitting foster parents, how do you know who your village is? If the signature behaviors of your bird identity are not instinctive, how do you know who to learn them from?