My pond is only small but it's given me endless interest over the years. Like the times when, usually in the spring, we've had two or three mallards taking up residence on it for a few days causing absolute havoc. Other times, even recently, we've had grass snakes in and around it chasing small frogs. I've spent ages watching damselfly larvae crawl up the reed stems to begin their incredible metamorphosis and been fascinated by caddis fly larvae lumbering about in their amazing cases made from bits of leaf stalks and other detritus.
When I first moved here 29 years ago the pond had goldfish and two small tench in it plus loads of frogs, you could easily count a dozen or more in the margins and you couldn't move a plant or weed in the garden without a frog leaping out and nearly giving you a heart attack. I've had all sorts of other fish in the pond since then including perch, rudd, golden orfe and roach. Most of these fish died of natural causes but I came home from work on a couple of occasions and saw a kingfisher catching the smaller specimens and have lost quite a few to herons on several occasions.
Over the years the frog population declined dramatically, until we were lucky to see a frog most of the time. This may have been caused by a virus which has been infecting frogs nationally for some years, I do remember a period when we were finding a lot of frogs just lying dead on the lawn during the summer which is when the virus is most virulent. I also know that goldfish and tench, being members of the carp family (cyprinids) have voracious appetites and are very partial to tadpoles. Two years ago I decided that I would try and reverse some of the decline in the frog population in the pond and garden. At that time the heron had recently wiped out the goldfish and all that was left was a single tench, or doctor fish as they used to be known, then one morning I looked out of the window just in time to see a heron stab it's beak into the pond and pull out the tench, so the pond was fishless for the first time in years and that's how I left it.
The upshot of this is that last summer my pond was full of tadpoles, most of which had a far better chance of survival now the fish were gone than they would have had, indeed I lost count of all the little froglets I found on the lawn and in the borders. The unexpected bonus was newts, last summer there were at least half a dozen adults in the pond and quite a few youngsters and although the adults do eat tadpoles, I saw them catch them on a few occasions, it's nothing like the impact that fish have. I read an article recently about newts returning earlier to ponds than they used to, sometimes coming back in November or December if the weather is mild, so last night while putting a chicken carcass out on the lawn for the fox, I shone a torch into the pond and there were two newts lying motionless in the remains of the weed. How they survived the freezing temperatures over the last few weeks beats me, especially with a two inch thick layer of ice completely covering the pond. I think they are smooth newts or common newts as they are called as opposed to palmate. As soon as I can net one I will check it out. I just hope that the frogs don't spawn too early this year as I believe frost can kill it if it's on or near the surface.