By Staff
The "hummers" split up and leave at different times.
Migration to southern Mexico, Central and South America can begin as early as late July to late October.
First to leave and start south are the males. Females follow about one month later. Bringing up the rear are the young.
They remain near the area where they were hatched, busily feeding and preparing their tiny bodies for the long, arduous flight ahead.
Then one day, the amount of sunlight triggers a migratory response and the young "dots" are on their way, headed south.
These young dots (some as young as 3 months old, second brood) are on their own, never before having made the trip. Yet they must go it alone! No map, no directions, no parent to follow. Researchers have only one answer: genetic programming.
And then if the trip down isn't miraculous enough, the following spring they are ready to make the trip back up to us.
Again, they return to the exact spot where they hatched and they remember where they consumed their first sip of sugar water the previous summer.
Each migration, thousands don't make it and perish. But yet, tens of of thousands do, and the ruby-throated hummingbird species carries on.
The wind, fog, rain and, deadliest of all, fatigue, exact a heavy toll on the poor dots
On the trip south, dots seldom fly more than 25 feet above the ground or water.
They mostly like to fly a straight course, but sometimes they may suddenly turn sharply, swerve, rocket and climb upward or plummet and dive downward.
In flight, dots fly 30 mph and beat their tiny wings 75 times a second.
On this trip south, across the Gulf of Mexico, a dot must fly some 500 to 600 miles.
About 10 hours would be necessary for the flight down if everything goes smoothly, with no storms or winds.
The tiny wings of the dot must beat without stopping some 2.7 million times to get it to the shores of Central or South America.
By the time it reaches its destination, it will weigh about the same as a penny.
I just find the whole migration utterly amazing.
First, the whole trip from wherever we might live, finding food down to southern shores is relatively simple, even though there are surely hazards, I'm sure. But the trip across all that water and non-stop to boot. Whew! Some more amazing facts about dots:
The ruby throated hummingbird's enemies are few, mostly because of its aggressive behavior.
Spider webs have been known to snare one occasionally. Some have been impaled on thistles. Others have been snatched by frogs and, believe it or not, some by flying too low over water, being caught and swallowed by fish that jumped out of the water after them.
But the deadliest foe it faces is weather.