Q: What is the #1 predator of the Ruby-throated hummingbird?
A: The house cat is the #1 predator for the Ruby-throated hummingbird. The second predator is probably the Chinese Mantis, a large insect. Note that both are invasive alien species, not natural predators of hummingbirds.
Q: Are the Ruby-throated, and other hummingbird species' populations increasing, or staying fairly consistent in numbers? It seemed like I had a lot more male RTH this winter. Was there a hummer baby boom by the end of the breeding season of 2011?
A: All North America hummingbird species populations, except Rufous, are steady or slightly increasing. Rufous appears to be slightly declining. Last summer was indeed a very good one for hummingbird nesting.
Q: Is there any data to suggest that some Ruby-throated hummingbirds live year-round as residents in Florida? I seem to have Ruby-throated hummingbirds here on the southeast coast all year long.
A: I don't know of any data, but that doesn't mean it's not happening. You're right at the southern limit of the breeding range. I wonder if your winter Ruby-throated are not the same birds as your summer visitors.
Q: When should I put out my hummingbird feeders?
A: Watch the migration map, and put your feeders out when the hummingbirds get close to you.
Q: Will hummingbirds nest in a noisy area? My friend lives near the airport in Wisconsin. She seldom sees any hummingbirds.
A: Probably not. Hummingbirds prefer quiet woods or wetlands with lots of flowers and bugs for nesting territory.
Q: With all the devastation in the South this year, how does that affect the migration? If shrubs and trees are destroyed the hummers will have limited places to perch.
A: Hummingbirds have been dealing with weather and its effects for thousands of years. As long as there's food, they'll be fine.
Q: How far north do hummingbirds fly?
A: Some Rufous Hummingbirds nest 100 miles north of Anchorage, Alaska.
Q: Why are hummingbirds called humming birds?
A: Because of the sound their wings make when they fly.
Q: Do the same hummingbirds and their offspring come back to the same place every year? I have several types of hummingbirds visit my feeders every spring & summer.
A: In general, yes.
Q: Do the same hummingbirds return each year to my feeders?
A: Most hummingbirds return each year to where they hatched, but not necessarily to the exact same yard--if they were a mile away, you'd never know it. Roughly 10-15% will be the same individuals every year.
Q: Do all individuals in the hummingbird species migrate?
A: No. Migration is an instinct encoded in a bird's genes; as such there is some amount of variation, and a small percentage of individuals will lack the instinct to migrate. If this leaves them in an inappropriate place to spend the winter, they will not pass those genes to another generation. That's natural selection at work. In some species, like the Anna's Hummingbird in California, the bulk of the population doesn't migrate because winters don't get cold enough to reduce the food supply.
Q: Where are the hummingbirds found in winter/summer months?
A: It depends on the species. Most North American hummingbirds winter in Mexico or Central America.
Q: Why are there "doughnut hole" areas on the migration map where there are no reported sightings? Looking at the map, I noticed that Kentucky is in a doughnut hole where there are no reported sightings.
A: This happens every year, but it's unusually evident right now. Ruby-throated Hummingbirds tend to migrate first up the Mississippi and Ohio River valleys, and north along the Atlantic coast. The areas in between fill in later, and the hole disappears. Also, spring comes a little later to higher elevations.
Q: When should I put out my feeders? We have had record setting high temps in Indiana. I normally put feeders out the last week of April. I have seen no activity, but one just never knows!
Q: Will the hummers arriving early be able to survive very cold temperatures and find food? I live in New Hampshire and am noticing that many people are seeing hummingbirds a full month early! I haven't seen any in my area yet, though they've been seen along the coast and down in eastern Massachusetts. There are even reports north of my home!
Q: Will cold nectar harm the hummingbirds? I put my feeders out a couple of days ago. Temperatures dropped into the mid 20's overnight!
We've seen very unusual weather this spring (2012). The east had several weeks of very warm temperatures, with strong southerly winds and no cold fronts. Normally, March has a cold front every few days, and the migration pauses while birds wait out the headwinds. For most of March, there was no bad weather to impede the migration.
The entire population of Ruby-throated doesn't migrate at the same time. The number and distribution of reports so far leads me to think that only a small subset of males took advantage of the weather to zoom north so quickly. Such inherited traits as migration speed and willingness to take a big risk presumably fall on a bell curve, and these are almost certainly outliers that in normal years would not survive to pass any genes to another generation. This is how evolution takes advantage of new opportunities as they arise, while ensuring that most individuals are in the fat, conservative part of the curve, with no urge to gamble their DNA.
Most of Migration Predicted to be Normal
So, my guess is that the bulk of the population will reach their destinations at about the same time they always do, regardless of the weather. As I write this in late March, I'm getting a lot of reports from Alabama, Georgia, and Mississippi, which is just what I'd expect in a normal year. I haven't seen my first bird yet, and won't be surprised if I don't until mid April. There's always an element of luck in seeing the earliest migrants.
Surviving Frigid Temperatures
Ruby-throated are stressed by prolonged frigid weather, but don't have much trouble with a few nights in the teens as long as there's food. I expect only the northernmost states and Canada will see more than an occasional subfreezing night again this spring. You can help the bold pioneers by putting out at least one feeder now, using the standard 1:4 ratio. Keep an eye on the syrup, and change it when it gets cloudy.