Natures wonders: navigating Albatross (Introduction)

by David Turell , Tuesday, January 16, 2024, 22:06 (101 days ago) @ David Turell

Uses infrasound noise from ocean waves:

https://www.scientificamerican.com/podcast/episode/how-does-the-worlds-largest-seabird-...

"According to a new finding in October’s Proceedings of the National Association of Sciences USA, this seabird navigates using sounds below our thresholds for hearing.

"The wandering albatross thrives in the circumpolar band of ocean north of Antarctica—a windswept region that the world’s best sailors say has the most inhospitable seas on the planet.

"On the Southern Ocean’s islands where they nest and brood, one wandering albatross parent tends the nest while its partner takes to the sea, traveling as much as 10,000 kilometers as it forages for scattered prey. The bird must eat enough to fuel its turn on the nest, which can be a long time ....Birds might go for, perhaps, a minimum of four or five days, up to 30 days.

"Wandering albatrosses actually gain weight on these long trips because they’re extremely efficient flyers.

"It almost never beats its wings. It’s quite fascinating to see them flying in the winds. When they’re flying, their heartbeat is the same as when they’re resting.

***

"With their long wingspan—the longest of any bird, maxing out at nearly 12 feet—wandering albatrosses use wind, air pressure gradients, and gravity above the swells and waves to soar for thousands of miles, reaching top speeds of 45 miles an hour.

"Basically, wandering albatrosses don’t fly. They soar.

"The more distance you cover, the more you may find food. The wandering albatross’s keen senses of sight and smell help it locate prey. But these senses are good for about 100 kilometers—a distance the bird can travel in as little as an hour and a half. So how does the albatross know where to soar toward?

***

"Infrasound is any sound below 20 hertz, where human hearing starts to drop off. At the very low end of the infrasound spectrum are microbaroms—very low-frequency sounds between 0.1 and 0.6 Hz that are detectable across thousands of miles.

"Microbaroms are generated by the collision of ocean waves.

***

"The constant hum of microbarom infrasound is called “the voice of the sea.” It’s present everywhere, all the time. But it’s unevenly distributed.

"Where you have more energy in the ocean system because you have wavier areas or windy areas, then you get louder microbarom regions.

"Ideal soaring conditions for wandering albatrosses.

"But it also gives them information about standing ocean waves, and this is often caused by things like storms. So it would enable birds to try and gauge where storms are, potentially. So this might be be cause they want to move toward windier areas that could be optimal, or they might want to move away from windy areas if they’re too strong, and they want to try and avoid storms.

***

"...using wind and infrasound data, create a sound map of the total flight area—a map of microbaroms across space and time. Send out another set of albatrosses equipped with sensors to field check the sound map. Finally, overlay the birds’ flight paths on the sound map.

***

"What the team found is that wandering albatrosses aren’t exactly wandering. Instead they seem to use microbaroms to head toward ideal wind conditions.

***

"We know that there is something about infrasound that they want to move toward, that they like, that is beneficial to them in some way.

"It was kind of a badly needed paper at this point because it sheds some new light into a fundamental question that is at the core of a lot of marine megafauna research in general but also at the core of seabird research, which is: “How do they manage to find food in such a vast area?”

"This reliance on infrasound may actually extend to other species, too." (my bold)

Comment: it is beyond our comprehension, but it works for them ans as my bold shows it might work for other flying organisms.