We’re all learning a lot about marbled salamanders this year! Everything you’d ever read about them says they won’t migrate to their wetland unless it rains and they don’t mate except on rainy nights. This year we had a movement of over 350 last week with no rain---but there was a front moving through. Last night was an even bigger migration and there was no rain at night. We had a few sprinkles during the day at the lab, but the rain gauge at the bay said NO rain. Yet, this morning three of us went out together because we just had that sense that last night may have been the closest thing to the right conditions that we’ve had yet. Sure enough we got several hundred. And man are the males ready! If you look closely at the picture on the top you can spot several spermatophores. The most obvious one is toward the upper right part--basically look for the bright white spot. The males put down a spermatophore which has a base that looks like a clear jelly and then the sperm packet is on the top. The females have to position themselves over a spermatophore and pick up the sperm packet. We put “floats” in all of the buckets--usually a piece of wood and in this case the males were using the floats as a mating ground! Unfortunately for them, most of the sperm was left on the base so doesn’t look like the females were quite as ready as the males. As an aside last year David Scott and I had a study going in which we collected every spermatophore put down by males in enclosures--now I have boxes and boxes of hundreds of spermatophores I need to extract DNA from. It’ll be a cool study when I finally get back to it! The picture on the bottom shows all the bins we used today to bring the manders back to the lab. Brian Metts is posing with the buckets. Brian is one of the guys who has “run” Rainbow Bay the most over the years.
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