The golden-cheeked warbler is one of the most at-risk birds in the continental U.S., a new study says.

The bird breeds exclusively on or near central Texas's Edwards Plateau and requires a habitat of Ashe juniper, according to the National Audubon Society.

Since much of those trees have been lost to urban sprawl and poor land management practices, the bird's numbers have dropped alarmingly.

Many of the birds put on a list of at-risk species are relatively obscure, because, like the warbler, they have a limited range and small natural populations, the study authors say.

These especially vulnerable birds require aggressive and immediate protection measures, the writers say.

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