Birdwatchers, or "birders" as they prefer to be called these days, are heading outdoors in droves to celebrate spring and the return of migratory birds to the Centennial State.
 
According to the Association of Colorado Field Ornithologists, 487 species of birds have been documented in Colorado.  That puts the state seventh on the list of which states have the most bird species.  California (637) and Texas (632) are the top two.   What makes Colorado unique is that it does not have an ocean coast line that harbors shore birds.
 
Bird watching is one of the fastest growing segments of wildlife viewing recreation with nearly 70 million participants, nationwide.  Each year, Colorado birders join thousands of others on the second Saturday in May to celebrate International Migratory Bird Day.  This year's date is May 10.  Wildlife enthusiasts use the date to recognize the winged wonders that travel the globe each spring and fall, migrating thousands of miles from their wintering to nesting grounds and back again.
 
International Migratory Bird Day was created specifically to highlight the migration of nearly 350 species of migratory birds that move between nesting grounds in North America and non-breeding areas in South and Central America, and the Caribbean. 
 
"This is the time that just about everything that comes through the state comes through," says John Koshak, a watchable wildlife expert with the Colorado Division of Wildlife (DOW). "Birds are looking for places to hang out, for any kind of water and any kind of trees or bushes that provide cover, shelter and food sources."
 
Birds tend to stop where they can find food and water.  Koshak says that means wet spots are the good places to watch birds.  That can vary from small urban ponds, streams, marshes, ditches, rivers or reservoirs. 
 
Koshak says that people can look for birds in the other places, too.  Like your backyard or wide-open spaces on the plains where you might see lark buntings, western meadow larks, scaled quail, sparrows, mountain plovers and burrowing owls.
 
Migratory birds are defined as those that spend part of their time in one habitat, and move to another to breed and winter.  In Colorado, some species "migrate" in elevation by moving between the plains and the mountains.   In contrast, the White-rumped Sandpiper spends the winter on beaches in Argentina, hop-scotches from wetland to wetland across the Americas, and nests on the tundra of the high Arctic. 
 
The longest non-stop flight ever recorded was reported last year by National Geographic.  According to a New Zealand researcher, a female bar-tailed godwit flew 7,145 miles from Alaska to New Zealand.  The bird flew for nine days straight without stopping for food or water.