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


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


March of Tetrapods, Elver Reluctance

Image: Nathaniel DorskyVia: Notebook

Image: Nathaniel Dorsky
Via: Notebook

A couple of updates on previous topics:

March of Tetrapods

That super cool fractal tool of the Tree of Life, OneZoom, has added all tetrapods to its phylogenetic work. With 70% of all currently described four-limbed creatures crawling around on the Tree, the next additions will be plant life and fish. I’m as excited as ever to see this tool expand its open science range as well as capability of harnessing various cyberspace knowledge bases to help users access articles, images and other information (such as level of endangerment) on the species listed.

The visualization of the increasingly complex big data of modern science is a genuine challenge, and I really admire what OneZoom is doing to bring together several related areas of study.

According to their website, OneZoom will also be working together to provide visualizations with Open Tree of Life, an organization working towards providing a unifying web-based resource that unites “biological research of all kinds, including studies of ecological health, environmental change, and human disease,” which “increasingly depends on knowing how species are related to each other.”


Elver Reluctance

I’ve written here and here about the hot competition for fishing licenses for American eel in Maine. I checked on the newly hatched fishing season on elvers today. The season opened at noon on March 22 with high hopes and hotly contested elver fishing licenses. Considering the boom year of 2012, which brought in $38 million worth of elvers (an estimated haul of 19,000 lbs/8600 kg), this is no surprise.

For the moment, neither the elvers nor the weather are being very cooperative about helping this crop remain Maine’s second-most important fishing sector after lobsters. Where last year’s temperatures were almost summery at 70°F (21°C), this year is a much colder 45°F (7°C). There is still snow on the ground from the latest storm to hit the East Coast. And the amount of elvers in the stream is lower as well, according to an official of the Maine Marine Patrol. Early 2013 prices were estimated at approximately $1700/pound of elvers, a little under a dollar per glass eel. Last year, the top price early in the season was $2000/lb. Once the elvers are shipped to the interim destination that awaits them (before a dinner plate, that is), the price can go to up to $30,000/lb. for them once they are grown.

The American eel has been considered for listing as an endangered species on and off for the last twenty years, but without concrete knowledge of the actual population size (I have read various estimates that range from ‘millions’ to ‘billions’), it’s difficult to say just where they stand. A bounty of elvers one year might mean the population is stable and healthy; it might also have been a birth boom year, and by harvesting several million of the young, long-term effects might impact the population several years down the line when there aren’t sufficient adults to mate. Last year I read an estimate that at $2000/lb., elvers were going for a dollar apiece. That’s 2000 elvers per pound, which means last year’s harvest removed something on the order of 38 million elvers from potential adult population of the future. (Admittedly, 2000 elvers/pound seems like a large number, but it’s the only one I was able to find.) For an eel population in the billions, that’s a drop in the proverbial bucket. For a population in the millions, that’s a lot of elvers.

For the fishing industry, it’s a gold rush. As one commenter says on the online news site for Maine’s The Bangor Daily News, “This seems like a once in a lifetime deal. Also…a bad night at fishing is still better than a good day at work!!”

The current boom in elver prices is a real time view of differing perspectives when it comes to species management.

One side sees abundance, the other uncertainty.




United States Fish & Wildlife Service – American Eel page

Differing perspectives here and here.

Fractalling the Paper Paradigm

Branch from the mammal tree of life - OneZoom

Branch from the mammal tree of life – OneZoom

The more information we gain about phylogenetic trees – the trees of life used to visualize species evolution and relationships – the more difficult it becomes to represent their intricate complexity within a traditional ‘paper paradigm’. I recently posted the avian circle, which is an excellent tool, and now I’ve come across another tool which could prove to be very popular.

OneZoom is a project that was introduced in late 2012 by James Rosindell and Luke Harmon. From their article published on PLOS Biology:

“Mega-trees” with millions of tips (species) are expected to appear imminently. Unfortunately, there has so far been no practical and intuitive way to explore even the much smaller trees with thousands of tips that are now being routinely produced. Without a way to view megatrees, these wondrous objects, representing the culmination of decades of scientific effort, cannot be fully appreciated.”

Born, appropriately enough, following a walk on the thinking path at Charles Darwin’s Down house, OneZoom uses fractal patterning in an interactive application to generate trees that can branch and grow, almost infinitely. Fractal patterns are infinitely self-similar, iterated, and detailed mathematical constructs having fractal dimensions. Fractals are not limited to geometric patterns, but can also describe processes in time. From the OneZoom website:

“Trees with millions of tips, richly embellished with additional data, can now be easily explored within the web browser of any modern hardware with a zooming user interface similar to that used in Google Maps.”

In addition, the trees are beautiful to look at, easy to use, have great flexibility and (even if this sounds like an advertisement for a new video game) they are just plain fun to explore. They can be embedded in websites and used for data entry, they can provide an interactive educational tool, and at some point I am sure people will create animations of particularly dazzling fractal tree climbing experiences. I’m sure more work is being done on some of the elements – it’s a little hard to get an overview, so the relative size of taxonomic groups isn’t yet readily apparent, and I’m not yet sure how ‘time’ can be visualized (for example, whether different branches within one group are all of the same age or not) – the OneZoom trees represent quite a remarkable revolution in the treatment of vast amounts of data.

The makers of OneZoom envision using the method for other Big Data applications, as well – monitoring of complex industrial processes, global financial data, complex computing structures including hardware and software, and family trees, genealogy and pedigrees.

Sometimes, when I hear people say they just can’t imagine life without their constant attachment to the virtual world, I find myself getting into a pair of boots, shutting the door behind me and going for a good, long, non-virtual hike. And then I come across something like the haunting OneZoom trees, and I almost have to agree: Virtual tree-climbing can be both fascinating and indispensable, as well.

Article: OneZoom: A Fractal Explorer for the Tree of Life – J. Rosindell & L.J. Harmon