South Tufa, Mono Lake

South Tufa, Mono Lake is just about as alien a landscape as you can get. Tufa towers form when calcium-rich spring water bubbles up through the alkaline lake water and calcium carbonate precipitates out. Normally the towers would be beneath the lake's surface, but due to the lake's lowered elevation (thanks, LADWP), they're visible along the shore. Before water was diverted from the streams filling the lake starting in 1941, the lake's level was at 6417'. In 1982, the lake was at it's lowest elevation, 6372', and had lost 31% of its surface area. That may not seem that low in comparison, but it's the elevation of the lake's level, not simply elevation. Imagine 45 feet of water above your head, covering over 60 square miles in area. In 1994, the California State Water Resources Control Board ruled that Mono Lake should be maintained at a level of 6,391 feet above sea level. When that goal is achieved many of the tufas will return to their underwater domain, but some will remain visible to visitors of South Tufa.

80% of California gulls (Larus californicus) in the state return to Mono Lake every year to breed (not all "seagulls" in California, just the one species). Many of them nested in a huge breeding colony on Negit Island until the lowered lake level exposed a landbridge, allowing predators such as coyotes and raccoons access to an all-you-can-eat omelette bar. Despite attempts to blow up the landbridge with dynamite (that's for you, Michelle), the predators were still able to access the island. Now the gulls nest on smaller islands found within the lake.

The gulls feed on the super abundant brine shrimp (Artemia monica) in the lake's waters and alkali flies (Ephydra hians) found in droves along the shore. Many of them pick their way along the beach, but some have a pretty slick technique that you can watch a bit in this short video.

If you look closely, you can actually see the droves of flies moving out of the way like waves. Tasty !

For more on Mono Lake, visit the Mono Lake Committee.