Monday 25 November 2013

Obscure bird of the week: The Great Grebe

We at NGB are introducing a new series showcasing our world's 'obscure' birds; from the poorly known, the recently discovered to the downright bizarre, starting with the Great Grebe. Each week a NGB member will be profiling the little-heard story of these birds, hoping to raise awareness, promote support and appreciation for the species. If you would like to contribute, email ngb.prmarketing@hotmail.co.uk
Great Grebe pair in Chile by young birder, photographer and film-maker Cain Scimgeour
It's a well-known but little uttered fact that bigger is better. Ok, so good things can come in small packages, but better things arrive in a huge cardboard box you can turn into a habitable fort afterwards. I mean; you'd rather a burger than a breadstick, tuna over a turbot and who even buys those fun-size Kitkats? We all know 'cosy' is code for 'cramped'. Therefore it's no surprise that the world's biggest animals get the press. "The Blue Whale, the biggest creature alive", "Polar Bear: largest land carnivore", "Komodo Dragon, king of the lizards". Even Capybaras, Mekong Catfish and King Crabs get a look-in.

So I'd like to introduce the most sizeable member of that middling bird family of grebes; the fantastic Podiceps major, or Great Grebe.

It's a terrible name. Really awful. Just add a 'crested' and you've got yourself the wonderful but tragically overlooked dandy weed-flinger of Eurasian waterways. Not the kind of title you want to merit a successful Google image search.

Ginormous Grebe would have been better. Or Periscope Grebe. Or The Loch Ness Grebe. I'll get onto the guys at the Birdlife checklist about that. Even its scientific name comes out as "Big Arsefoot", which is a good description, but it's not the most flattering latin tag.

It's an iron-grey and rust-red present day Plesiosaur, with flat rubber-glove feet and a gleaming silver Excalibur bill, the stuff of fishy, froggy, crabby nightmares. They're even known to take the chicks of coots; of which there are several species in South America, each with its own gaudy frontal shield; an avian alternative to the family crests of mansion houses and people who own too many Labradors.
One such species is the Giant Coot, a hulking T. rex of a fulica, which if occurred in the UK, would scatter the swans and wrestle the bread-throwing park-goers to the ground. I imagine when coot and grebe meet, the scene is reminiscent of "King Kong vs. Godzilla" only with more armadillos and less screaming Japanese people.

Battle of the century: Arsefoot and Cootosaurus
Thanks to their ability to chow down on most aquatic life, they're found across large water bodies in western and southern South America, from rocky coasts hugged by sea lions to the guanaco-frequented lakes of the Argentinian Chaco, with inland birds succumbing to the lure of the sea once breeding is over.
The breeding itself is a confusing affair: Stretched out across the whole continent of South America, it's bound to not be uniform, with some populations even breeding at any time during the year. Elsewhere, laying occurs between October and January, even later in southern populations, and to throw another spinning plate to the mix, the isolated Peruvian population may breed twice a year: between September-October and January-February.
The infamous grebe pre-breeding ceremony is not well-executed in Great Grebes. Perhaps they're unimaginative, or clumsy, or just bad at flirting. It's a minimalist display; all synchronised swimming, slow head shakes and raised black crests (think Elvis quiff meets Basking Shark fin). No veggie props, no angelic water-dash, not a lot to get Bruno Tonioli shouting. Copulation is ungainly and awkward, heaved out on a constructed raft of vegetation; the soon-to-be nest.

As both mum and dad possess a brood patch, incubation of the 3-5 mud-stained eggs is shared, as is the free ferry service the adults provide once the young giants hatch. Extremely protective parents, Great Grebes are well known for their aggression, probably because they keep getting hit on by sleazy sheldgeese. A short-tempered grebe lowers its head and neck, with the bill almost parallel to the water service, apparently the level of lividness can be determined by the amount that the neck has been lowered. Failing this, the grebe displays it's hanky white underwings. Terrifying.

The mathematics of Great Grebe threat displays...honest
Thankfully, this leviathan lake dweller species is ranked as Least Concern by Birdlife International. This may be partly due to its large range of over 2million km, ability to breed during much of the year and a largely catholic diet. This carefree badge cannot be worn by many of the other South American grebe species, though. It's a sad state of affairs, with a quarter of the South American species ranked as critically endangered, and one species, the Colombian Grebe was officially declared extinct in 1981. Threats to South American grebes include drowning in gill-nets (with a shock figure of one dead Titicaca Grebe per net each day for both of the 2 fishermen evaluated during a study in 2005), chemical contamination from metal mining, introduced fish (particularly the Rainbow Trout) and fluctuations in lake water levels due to hydroelectric plants. Any hope held for these species evaporates further when one realises that some species are limited to just one or two lakes.


So whilst Podiceps major might have it best living it large, spare a thought for its smaller contingents, slowly becoming tiny shadows on the great birding map. 

Read more about threatened South American grebes here.
Read Birdlife's Hooded Grebe (critically endangered) project here.

-Jonnie Fisk
Jonnie is an 18 year-old Yorkshire-based birder, invertebrate enthusiast and frustrated artist. When not being oblivious to every local rarity, he enjoys autumn vis-mig and being distracted by bugs. 

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