Turtle Chirps, Volcanic Whistles

Anathasius Kircher, a 17th-century German Jesuit priest and scholar, had interests ranging from fossils to hieroglyphics to micro-organisms and volcanoes, was above all a master of expressing wonder at the natural world.

He proposed, among many other things, the idea of a parabolic horn, an amplification system for sound waves. In the illustration below, the sound waves are created by human voices. We do so like to hear ourselves talk. And we like to think we hear everything around us.

Parabolic amplication  by Athanasius Kircher (Musurgia Universalis, Rome 1650)

Parabolic amplification by Athanasius Kircher (Musurgia Universalis, Rome 1650)

But consider all the sounds and songs we can’t hear without the help of other mechanisms, the technological great-grandchildren of Kircher’s giant seashell horns.

The low chirps and meows of sea turtles, which apparently have distinct songs for mating, laying eggs, and for setting off on their first ocean journeys. Turtle hatchlings were recently discovered to use vocalization to improve their odds of survival by migrating together, and they responded to vocalizations of adult females up to hundreds of miles away from their nesting beaches. If they could hear them over human-produced noise pollution, that is.

Here’s an incredible collection of animal sounds, the Macaulay Library, from around the world. I particularly like this haunting recording of a lone common loon.

Plants have been found to communicate with one another via sound frequencies – some even speculate that they use fungi networks in forest floors as sound switchboards.

A water-powered automatic organ by Athanasius Kircher (Musurgia Universalis, Rome 1650)

A water-powered automatic organ by Athanasius Kircher (Musurgia Universalis, Rome 1650)

There’s whistling lightning – not the cracks you might have heard during a storm, but very low frequency radio waves sent out by some (though not all) lighting strikes just before they burst. There’s an entire network devoted to listening for whistlers (listen here), which have also been found to be connected to volcanic eruptions.

And then there’s the music of the spheres – or at least, the sphere upon which we live, Earth. The rings of plasma which form part of the planet’s giant magnetosphere are bursting with radio waves, which produce a sound sometimes called Earth’s “chorus” (listen here).

Why do I mention all this?

Because I was thinking this morning, while listening to the dawn chorus of birds, about the fact that, even if it’s just out of our range, not necessarily intended for us and we can’t always hear it, there’s music all around.

Illustration of Earth's plasma rings. Source: FeelGuide

Illustration of Earth’s plasma rings.
Source: FeelGuide

Curlew Farewell

Flocks of Eskimo Curlew Source: Cornell Lab of Ornithology

Flocks of Eskimo Curlew
Source: Cornell Lab of Ornithology

The last time an Eskimo Curlew was seen and positively identified, it suffered the same fate as when it was first officially identified and illustrated by John James Audubon himself: It was shot and then examined by an ornithologist.

Eskimo Curlew (Numenius borealis) Source: BirdLife International

Eskimo Curlew (Numenius borealis)
Source: BirdLife International

It’s been exactly fifty years since that last bird was felled, and as such, it has attained a sad definition threshold for moving from the ‘Critically Endangered (Possibly Extinct)’ list to that of ‘Probably Extinct’. Known breeding grounds have been empty since the late 1930’s.

So stop the clocks for just a moment and consider the once-abundant Eskimo Curlew that replaced the hapless Passenger Pigeon as the game bird of choice (until it was put under protection in 1916), ponder the swift demise of the Eskimo Curlew that once darkened skies with their density, and which disappeared with alarming and almost baffling rapidity.

It wasn’t just the hunting that led the Eskimo Curlew down that long path of no return, it was two other key factors, combined with uncontrolled hunting.

Suggested migratory route of the Eskimo Curlew. Source: Cornell Lab of Ornithology

Suggested migratory route of the Eskimo Curlew.
Source: Cornell Lab of Ornithology

According to the Cornell Lab of Ornithology, “during its migration northward in April and May, the Eskimo Curlew depended almost exclusively on the abundant insect foods of native tallgrass and mixed grass prairies. In the late 1800s, these critical habitat patches were virtually eliminated by wholesale conversion of prairies to agricultural fields and by widespread suppression of wildfire.

“(Also), extinction of the Eskimo Curlew’s primary spring food item, the Rocky Mountain grasshopper”, played a key role.

The Eskimo Curlew branch of the Tree of Life. Search the Curlew's name to zoom in further and see its status, along with that of its nearest relatives. Source: OneZoom (Birds)

The Eskimo Curlew branch of the Tree of Life. Search the Curlew’s name to zoom in further and see its status, along with that of its nearest relatives.
Source: OneZoom (Birds)

Over on the OneZoom phylogenetic tree of life, the Eskimo Curlew is still marked in the more hopeful red of ‘Critically Endangered’ rather than the funereal ‘Extinct’ blue of the long dark night – the Curlew still hasn’t been officially declared gone for good. The State of the World’s Birds, released by BirdLife International this June, stated that one in eight bird species around the world is currently on the brink of extinction.

Perhaps a small Eskimo Curlew cluster has taken up a hermetic residence somewhere unexpected, and will surprise us all with a miraculous re-appearance. Until then, we have the famous illustration by Audubon, who prophetically compared the Eskimo curlew to the passenger pigeon while both species still filled the skies.

Wildlife artist John James Audubon's famous portrait illustration of two Eskimo curlews as seen during his 1833 research expedition to Labrador. Photograph by: Handout , Postmedia News

Wildlife artist John James Audubon’s famous portrait illustration of two Eskimo curlews as seen during his 1833 research expedition to Labrador.
Photograph by: Handout , Postmedia News

More:

Great article on about the Eskimo Curlew and its significance on Canada.com – From endangered to extinct: the tragic flight of the Eskimo curlew by Randy Boswell