Your pond sounds pretty shallow. I used to play field hockey on frozen farm
ponds just an hour east of Cincinnati. You'll get a frozen pond when the
weather is really cold, but have you thought about aeration to prevent
freezing when it's just moderately cold? Or just seine up your fish for the
winter.
It can look ugly, but netting will work for herons, especially low around
the shoreline because they're wading birds. If you have kingfishers, then
netting all over the pond. Really, though, I think to have a problem with
these birds you'll first have to acclimate them to the pond with a constant,
abundant and easy source of food, and it doesn't sound like you're doing
this anyway.
You may get uninvited snapping turtles, too.
-- Jay DeLong Olympia, WA /----------------------------------------------------------------------------- /"Unless stated otherwise, comments made on this list do not necessarily / reflect the beliefs or goals of the North American Native Fishes / Association" / This is the discussion list of the North American Native Fishes Association / nanfa_at_aquaria.net. To subscribe, unsubscribe, or get help, send the word / subscribe, unsubscribe, or help in the body (not subject) of an email to / nanfa-request_at_aquaria.net. For a digest version, send the command to / nanfa-digest-request_at_aquaria.net instead. / For more information about NANFA, visit our web page, http://www.nanfa.org