The massive annual spring migration of America's birds – millions of them – is underway. Here's how to follow along at home.

The population of butterflies - the beautiful insects that play a vital role in pollination and the health of ecosystems - ...

The common grackle is larger than a red-winged blackbird but ... not rounded like boat-tailed grackles. These birds are common from Texas and Oklahoma to southern California.

Also the red-winged ... estimated 20 million birds were predicted to be migrating in the United States. Areas of high migration include Iowa, central Texas and up into Oklahoma.

tailed orange and Mitchell's satyr - plummeted by more than 99%. Nine species - about 3% of the total - showed gains. Among some common species, the red admiral declined by 58%, the cabbage white ...

tailed orange and Mitchell's satyr - plummeted by more than 99 percent. Nine species - about 3 percent of the total - showed gains. Among some common species, the red admiral declined by 58 ...