Scientists have discovered a new variety of water flea in a roadside pond on the Seward Peninsula outside of Nome, suggesting that life in the Alaskan Arctic may be far ecologically mysterious than previously thought.
This tiny crustacean — now named Eurycercus beringi — was identified during a multi-year, trans-continental investigation of water fleas that squiggle through small lakes across Alaska, Siberia and other Northern Hemisphere locales. The creatures fill a niche near the bottom of the freshwater food chain, providing summer food for birds while munching on even smaller life that erupts during the intense, brief Arctic summer.
Among other things, the scientists documented 10 different species of water fleas in these northern ecosystems instead of the two previously thought to live there. That represents a remarkable five-fold increase in water flea diversity in the Far North.
With summers growing warmer and vegetation shifting, aquatic life unknown to modern science might be squirming incognito off the toes of our XtraTufs in potholes and tundra lakes that have begun to vanish and shrink. As these water bodies drain into the Earth or dry up, their biological treasures could vanish with them.
"It is well known that parts of Alaska and Siberia have suffered a huge reduction in freshwater surface area, with many lakes and ponds disappearing permanently in the past few decades," explained co-author Derek J. Taylor, a biologist at the University at Buffalo, in this story about the research. "What we're now finding is that these regions with vanishing waters, while not the most diverse in the world, do contain some unique aquatic animals."
"Some of these subarctic ponds that water fleas inhabit are held up by permafrost, so when this lining of ice melts or cracks, it's like pulling the plug out of a sink," Taylor added. "When you see the crop circle-like skeletons of drained ponds on the tundra you can't help but wonder what animal life has been lost here."
Along with Eugeniya I. Bekker and Alexey A. Kotov of the A. N. Severtsov Institute of Ecology and Evolution in Moscow, Taylor concentrated on the quarter-inch-long water fleas from the genus Eurycercus in ponds across the globe. One surprising finding? These particular water fleas appear to be more diverse in northern regions than in the tropics.
"This is a counterintuitive concept, as scientists have long supposed that the advance and re-advance of ice sheets reduced much of the species diversity in colder climates," Taylor explained in this story. "However, there is growing evidence that some northern areas remained ice-free and acted as hideouts during the harsh glacial advances."
Contact Doug O'Harra at doug(at)alaskadispatch.com