The smallest bird in the world turned out to be unsuitable for harsh mountain conditions. This greatly limits the places hummingbirds can migrate to in warm climates.
Meanwhile, climate change has had global and partial irreversible consequences for people and nature. For example, there is massive transmission under our noses. It is animals. More and more animal species are migrating to new, cooler regions. One is heading towards the poles, the other is heading towards the top. But what will the hummingbird do? Is life in the mountains reserved for this beautiful bird?
Hummingbirds
To answer this question, scientists took hummingbirds on a trip to the mountains. Birds were hunted at different locations. For example, researchers lure hummingbirds that lived only 10 meters above sea level, as well as some species that live at an altitude of 2,400 meters, into the trap.
…Can a hummingbird travel 385 times its body length in one second?
Metabolism
Hummingbirds were first brought into a cage at an altitude of 1215 meters. After a few days, they were given a funnel containing a tasty syrup, which the researchers could use to measure their metabolism. Later, the team also measured the metabolism during the hummingbirds’ “mini-hibernation.” This is a wonderful sleep state in which birds are at night. Then they become completely motionless and do not react to anything.
Hummingbirds sleep only at night. During sleep, the body temperature drops a few degrees to save energy, similar to hibernation in bears. This is accompanied by a decrease in heart rate and other normal functions.
After these first trials, the hummingbirds were taken to a nearby research station at an altitude of 3800 metres. Here the air is not only much thinner (there is about 39 percent less oxygen in the air), but it is also significantly cooler: mercury does not rise above a barren temperature of 5 ° C. Four days after this step, the researchers measured the hummingbirds’ metabolism again.
efforts
Although the birds had to work harder to stay warm in the thinner air, their metabolism dropped by as much as 37 percent. Moreover, all hummingbirds (that is, birds that live at an altitude of 10 meters above sea level, and birds that reach an altitude of 2,400 meters) had the same difficulty with mountain conditions. Not only did they have more problems staying supine, they also became sluggish at night for extended periods, spending more than 87.5 percent of the cold night in their little slumber.
conclusion
“Overall, these results indicate that lower air pressure and lower oxygen significantly affect hummingbird flight performance,” researcher Austin Spence concluded. “In addition, it shows that hummingbirds seem to go into a little hibernation for a longer time when it’s very cold.”
They are interesting the findings† But what does this mean for the future of hummingbirds, as climate change also forces these birds to seek more comfortable conditions? “They seem to have a hard time adjusting to the mountain conditions,” Spence says. That means we probably won’t see a hummingbird in the mountains. Instead, the researchers say, they are more likely to move north in pursuit of cooler.
