Sometimes in July, the Roufus Hummingbirds begin arriving at our feeders. Identifiable by their reddish copper color, they are very aggressive; protecting whichever feeder they select to drink from against other hummingbirds. These birds are arriving in the middle of their migration; traveling from Alaska to the south for the winter.Beginning in August, millions of other species of hummingbirds will travel as well to Mexico and Central America as part of an instinctive migratory pattern that they have followed for hundreds of years. For many, this trip includes a trans-Gulf, nonstop flight that takes approximately 18-22 hours and covers 500 to 600 miles. Bird enthusiasts can expect to see waves of hummingbirds visiting their feeders during this time.At the peak of migration, bird-banding studies indicate that, with very few exceptions, the hummingbirds that visit feeders on any given late-summer day are completely replaced by new migrants within 24 hours. To estimate a total number of hummingbirds using your feeders daily, multiply times five. For example, if you see 10 individual hummingbirds at your feeder at one time, you have about 50 passing through your yard that day.Hummingbirds feed on flower nectar, insects, and sugar-water solution placed in specially designed feeders. Despite popular belief, hummingbirds do not suck up nectar with their bills. They actually lap it up with their tongues, drawing nectar from its source up and into their mouths almost 12 times a second. You can watch this remarkable tongue in action with some window hummingbird feeders. These feeders feature a transparent bowl that allows you to watch a hummingbird's long tongue and rapid lapping action. A high-calorie diet is important to sustain these very active birds and to build fat reserves for their migratory trip. Hummingbirds possess the fastest metabolism of any warm-blooded animal on the planet, consuming up to twice their body weight in nectar every day. The color red is a visual cue to let hummingbirds know food is available. It is recommended that you not add red food coloring to nectar. If the wrong type of coloring is used, it can make the egg shell hard and difficult for the babies to break open. Instead, pour the clear nectar into a red-colored feeder to attract these amazing birds. Hummingbirds are fun to watch, and most of us hate to see them go. But it won't be long before spring is back, and they will be close behind.Local bird expert Larry Collins owns Wild Birds Unlimited, 2454 Hwy. 6&50, which caters to folks who want the best backyard birdfeeding experience possible. Email your birdfeeding and birding questions to firstname.lastname@example.org and he'll answer them in his bi-weekly Q&A column in the Free Press.