Pond denizens struggle against mud
On a short afternoon hike at Sanborn today, Dave and I decided to go by the tiny koi pond near the visitors' center to see if any newts were left this late into summer.What a scene! In the current semi-drought, the pond has become a mud flat, its surface criss-crossed with tracks and squirming with newts and crayfish trying to push themselves out of the sticky mud.
In the few holes where the water was more than a couple inches deep, fish flopped -- several 6-8" long golden koi plus something brown but similarly large. A few of the newts thrashed in the water holes, too, seemingly trying to get clean of the mud that coated them; but most of the newts wriggled across the shallower mud flats, heading nowhere in particular but looking very unhappy. The crayfish seemed most numerous at the dryer edges of the pond, pushing themselves laboriously up out of the mud with their claws and dragging themselves across the mud.
Newts normally migrate, and can go surprisingly long distances (miles) across land, so I think at least some of these newts will survive. The fish, I must assume, are doomed unless someone rescues them. I wonder if the rangers have considered selling the non-native koi to someone who wants them, and replacing them with native fish? Are there any fish native here this far upstream? Penitencia Creek (at Alum Rock) has small fish (up to about 3" long), but it carries more water in dry seasons than any creek near Sanborn.
What about the crayfish? Can crayfish survive long out of water, bury themselves in mud (the ones here didn't seem too happy about that idea) or migrate overland?
I suspect there will be some happy park raccoons tonight.
[ 21:21 Aug 21, 2008 More nature | permalink to this entry | ]