Researchers have long wondered why so many bird species fly such extended distances during their migration patterns, but a new study published in the journal Nature Ecology and Evolution this week appears to offer some much-needed insight.
Image Credit: Pixabay
As paradoxical as it may seem at first glance, these long-distance trips may help certain birds conserve energy; this is especially the case for birds that cope with substantial prey competition back home.
Models from the study indicate that while these long flights aren’t without their weighty energy demands, the birds balance it out in the long run. In particular, there’s considerably less prey competition at their destination.
Birds of different kinds migrate to vastly different places, and this global redistribution helps to spread them out. With fewer birds clogging up a particular area and stealing all the available prey, they don’t have to work as hard to obtain their food.
But why do they only migrate during certain times of the year? A good question, which can be answered by the model.
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Many birds like to eat specific insects or plants, and these are plentiful throughout the birds’ home turf during the warmer months. But as the fauna and flora fade away for the colder months, they become more challenging to find, generating more competition among birds. This small factor drives the migration patterns we observe.
“There's just one rule and one mathematical model that explains the whole thing,” said Marius Somveille, the lead author of the study.
“The tropics are so crowded, that at some point some species find it a better strategy to migrate to a place with a surplus of resources.”
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But not all birds migrate, and the reason behind this remains a mystery. Unfortunately, this study doesn’t provide any answers concerning the species-specific nature of this migratory behavior, but future studies could.
This study may even serve as a springboard for understanding why other animals migrate, but that has yet to be validated.
Source: Washington Post
