Thursday, August 1, 2013

Tufa Time

 

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Mono Lake is famous for the tufa towers along part of its shoreline. No, we didn’t know what a tufa was, either, so we decided to take the 10am naturalist guided hike at the South Tufa Area. This is a fee area ($3.00 pp) but Jim’s senior pass got us in for free. It’s so nice that he’s old(er).

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Here are some of the things we learned: Mono Lake is thought to be at least 760,000 years old and has no outlet. The streams that flow into it carry salt and other minerals, and as the water naturally evaporates, the minerals are left behind. As a result Mono Lake is extremely salty and alkaline. No fish can live in it, but alkali flies and brine shrimp thrive here. Tufa is a limestone deposit that forms when fresh water springs containing calcium flow up from beneath the lake and react with the carbonate-rich lake water, which means they can only form under water.

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We wouldn’t have been able to see the tufa today had the city of Los Angeles not purchased the water rights to the streams that flow into Mono Lake in the 1940s. As a result of diverting this water, the level of Mono Lake eventually dropped more than 40 feet, exposing the tufa. The environmentalists began to take action in the late 70s and finally succeeded, although it took until 1994. LA is still diverting water, but in much smaller amounts to allow the lake to refill. They are only going to let it refill to 1963 levels, which will keep most of the tufa exposed. Have to keep those tourism dollars coming in, I suppose.

Enough history. These alkali flies feed on algae along the shoreline, and are high in fat and protein. Unlike regular flies they have no interest in humans, but they attract over 300 species of birds, many of them migratory.

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Good eating!

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The birds also feed on artemia monica, a type of tiny brine shrimp that live in the lake.

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We had a fun and educational morning. I’ll leave you with some photos of a few of the birds we saw.

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Mono Lake is a nesting place for many osprey. A volunteer had a scope set up so we could see these fledglings.

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This is really a beautiful place.

7 comments:

  1. I'd say that program was worth it to learn all of that stuff. It's a good thing those flies don't like people or no one would visit. :)

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  2. I've stopped by that lake several times and just sort of wondered, "What IS this?" Thanks for the lesson. Also, great pics of Yosemite...still my favorite national park I think, just love the valley.

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  3. I've been by here several times, never took the tour. Thanks for the info.

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  4. I've always just driven by the lake, never had the chance to really give it a good look over. I'm looking forward to spending time there now that we have the RV!

    Metamorphosis Lisa

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  5. Hey, wait a minute. 760,000 years old? I thought the earth was just 6000 years old.

    Lovely photos.

    Chris H

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  6. Those guided hikes really are almost always very educational. Thanks for sharing the information. Very very interesting. Flies that don't like people and attract birds sound like a great idea as opposed to the black flies of New England that apparently live to bite.

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  7. Chris, there goes that science thing again.

    Jim

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