A new study finds the popular, fluttering insects have declined by 22 percent in the last 20 years

We're charting migrations this season, announcing when a variety of species hit major milestones on their travels north.

With more than 10,000 described bird species in the world, some of them are bound to be a little, well, unusual.

ALT: a man wearing sunglasses and a white shirt is throwing salt into the air .

Scientists have found unprecedented evidence of another type of squirrel exhibiting carnivorous behaviors, including hunting, killing and eating voles, according to a new study.