Well.. George, so your a geologist! Exactly what I have wanted
to be all my life. Your post was music to my ears ...

Nedra
http://www.geocities.com/Heartland/Pines/4836
http://community.webshots.com/user/nedra118

"George" wrote in message
.. .

"steve evans" wrote in message
...
Our pond is right at the edge of a 50 acre wetland. There is no stream
inlet or outlet. When we had the pond dug the excavator said it was
spring fed and you see two areas at the bottom that remained clear for
years. The pond filled in a couple days and the level varies very
little, even in the dry summer months. We bought the bluegills and bass
from a fish hatchery and put in no bullheads. And didn't see any for 20
years or more.


Do you live in a karst area (cave country)? You said you have marl at the
bottom. Is it solid, fractured, or does it have crevaces and/or possibly
a cave
passage at the bottom? The reason why I asked is that if the opening is
large
enough, or has enlarged over the last year, your fish may now be swimming
somewhere else, or else found themselves lost in an underground bedrock
channel,
and couldn't find their way back. In that case, they probably starved. I
know
this sounds goofy, but I am a geologist and live in Kentucky where we have
lots
of caves and cave springs. It is not unusual for ponds in certain areas
of the
state to suddenly loose all of the fish. I actually saw a sinkhole open
up in
the bottom of a pond once, and drain the entire pond, fish and all, in
about 10
minutes. That obviously didn't happen to you, but if there is a submerged
passage (the spring water has to be coming from somewhere, possibly the
marsh),
it won't drain the pond, but actually feed water to it, as you've said
that it
does. If there are openings in the bottom large enough for fish to enter,
they
generally will.