I noticed in the park that the sea gulls soar high up in the sky, and that the robins and such stay down by the ground
I am assuming (correct me if I’m wrong) birds basically have an altitude level which they keep at when they are flying.
So what happens if you go up in a plane a few thousand feet and drop a robin out of it? Since that is so far above it’s normal cruising altitude would it be able to fly down safely?
I am ignoring all the things like wind resistance and stuff like that. I guess basically I want to know if the altitude at which a bird flies limited by the bird and it’s habbits or is it limited by it’s physical build
A better way to visualize what I think you’re after is to suggest taking the bird up in a balloon and releasing it, avoiding questions about wind-buffeting and so on.
Until one of the ornithologists happens along:
Birds generally don’t fly very high because they have no reason to - it would be silly for them to expend a lot of energy on elevation gain which serves no purpose. Even the sea gulls you observe, or high-flying raptors aren’t flying all THAT high. They gain some height to be able to survey for food better, but not thousands of feet off the ground. Even with the visual acuity something like an eagle has, there’s a limit as to how high it can fly, and still spot prey on the ground. I believe some soaring species get higher off the ground than would serve a practical purpose during courtship displays.
Birds sometimes attain a lot of altitude during migrations, which gets them up above the weather. Including some very small birds. There are species which migrate over the Himilayas. Those species are have adaptations for breathing the thin air, but the general design of birds is pretty good for it in the first place.
WAG:
I’m guessing that even a non-migratory bird which is not normally a high flyer would have no trouble finding its way back to lower altitudes when released from the balloon, provided it’s not enough altitude for the thin air to be a factor. A bird which does not normally fly any distance might be in trouble because it would tire out. I’m thinking of various chicken-like birds here, that normally only fly from bush to bush.
Habits mostly. Altitude is a relative thing in your example. A robin will fly so many feet above the ground regardless of location. So a robin in Denver will fly 5,000 feet higher than a robin in Tampa because Denver is 5000 feet above sea level.
100% of what birds eat is on the ground. Flying is just transportation andonce they get above the trees there’s not a lot of advantage to going higher. If the wind is with them they can gain by climbing to 100 feet or so, but birds are rarely higher than that.
OTOH, as a jet driver I’ve hit migrating geese at 8000 ft above sea level, 7000’ above the ground.
One fine day we hit some small bird at 28,000’. Damned if I know what it was or how it got up there. But it made the traditional bloody, feathery mess, so I doubt it was an alien or a meteorite.
For any reasonablly breathable altitude, say beow 18,000, my speculation is a typical bird could fly fine & would simply head down to Earth. As yabob points out, birds that don’t fly far would have a hard time staying in control for the many minutes needed to descend from 18,000.
Birds also don’t generally fly in clouds and if they were released above a solid undercast I imagine they’d have a hard time getting through it without crashing. The good news is even if they just stowed their wings & fell, they don’t need much altitude at the bottom to recover control & land safely.
This Staff Report How high can birds and bees fly?, by me (George) and Doug, answers the question posed in the OP. A robin shouldn’t have any problem flying down from quite considerable heights.
I don’t suppose you saved a feather or two? That would be a new altitude record for a small bird, the maximum I am aware of being that mentioned in the Staff Report of 16,000 feet for a Blackpoll Warbler.
Except for swallows and swifts, that feed on flying or drifting insects.
That was a good one. It’s a shame how many of those “bird at high altitude” stories end with the bird colliding with a plane, though!
Why on earth would a non-migratory vulture be seven miles up though (and over the coast, not a mountain range)? It couldn’t possibly be searching for food from that altitude, could it?
Thanks. Given the relative airspeeds, though, it is often the only way the bird ends up being identified (from the feathers, or more recently DNA) because of the remains left on the plane.
That’s a very good question, and as I said in the Report, one that puzzles me. Even the most keen-sighted vulture probably couldn’t identify food from that altitude. However, some vultures here in Panama seem to spend a lot of time just “loafing” in the air, soaring around in circles when they are obviously not looking for food. It may actually be easier for them to thermoregulate when they are aloft rather than perched in the tropical sun. Also, the small adjustments needed to soar on thermals could actually require less energy than standing. But that still doesn’t explain why a vulture would go quite so high.
Altitude here in Bogotá, Colombia is 8678 ft. There are plenty of birds of many species flying around here. Sparrows and hummingbirds are plentiful as well as hawks and eagles. They don’t seem to have any problems with high altitude.
I’ve always heard them called “nighthawks”, nightjar is new to me, but google has a million “nightjars” and five million “nighthawks”, however many of the nighthawk hits are for aircraft, bands, etc. I will call them nightjars from now on.
Anyway, they are way cool birds. I did a necropsy on one and the crop was a huge mass of tiny insects. Imagine a chicken egg sized ball of bugs.
