If you tend a hummingbird feeder you’ve surely noticed a slow down in activity.

That’s because your regular customers have already bugged out for their winter retreat in Central America. The ones hitting your feeder now are from farther north. Here in the northland hummingbirds start moving out in August and all are plying the skies by mid September.

A myth with hummingbird feeding is you should take your feeder down before migration time or you’re fatally enticing them to stay too long. That’s not so. Like nearly all migrating species, their flight schedule is dictated by day length, not food availability or temperature. They’re wired to leave when there are still plenty of delectable insects and blooming flowers throughout their journey.

Not a lot is known about hummingbird migration. The only hummer species we have here in the East is the ruby-throated.  We know they migrate along certain flight paths but do so individually instead of in flocks. This makes sense for several reasons. One is their best predator defense is their small size which makes them difficult to see. A flock would be much more conspicuous.

Also, there would be re-fueling issues with a flock.  Discounting insects, hummingbirds have the highest metabolism of any animal with heart rates over 1,200 beats a minute recorded. Under normal circumstances they can only consume enough food during the day to just get them through the night. I’ve seen this first hand. Several times hummers have stumbled into my garage, which has a quite high ceiling. They must not be the sharpest knife in the drawer for despite two wide open overhead doors they just buzz around high in the rafters unable to solve the riddle of how to get back out. The next day I find them dead.

At migration time they fudge this a bit. They are able to binge feed (why NOT to take your feeder down early) and pack on up to 40 percent more body weight which allows them some extra time between chow stops. They still must eat regularly during migration, though. Since flowers are so scattered it just ain’t gonna work for a whole flock to line up at one or two flowers.

Ruby-throated hummingbirds winter in southern Mexico and Central America. Since they migrate individually young birds don’t learn the migration route from their elders like many other species. A young hummingbird simply has the innate urge to fly in a particular direction for a certain length of time, then stop and hang out a few months. Most follow their original pioneered route for the rest of their lives, which on average is three to five years but can be more than nine years. They return to the same area, both ways, every year.

Some of the hummers summering along the East Coast make an amazing, 450-mile, non-stop, 20-hour flight over the Gulf of Mexico. That’s a Herculean feat for a tiny wisp of muscle weighing no more than three paper clips even on a good day. Routine this time of year, though, are stiff head winds, storms and even hurricanes. In reality, this Gulf crossing is much more common in the spring when the weather is calmer and the prevailing west winds are at their back. In the fall many opt for the safer inland route along the coast line down through Texas and Mexico.

Migrating hummers take advantage of the wind at every opportunity. Whenever the wind is blowing in the direction they need to go, they are on the move. The stronger the breeze the more birds riding it. Their comprehension of wind is apparently far superior to that of garage escape.

They migrate at a fairly leisurely pace, averaging about 20 miles a day. They fly at tree top level, very low for a migrating bird, presumably so they can spot flowers for fueling up. They mostly fly during the day and sleep at night. They frequently take extended rest stops, but only for a few days before moving on. It takes those from here in the north three to four weeks to make the trip. Keep your feeder up, for weary, hungry travelers are still coming through.

Carpe diem.

Larry Lyons writes a weekly outdoor column for Leader Publications. He can be reached at larrylyons@verizon.net.