Can my garden pond ever support both ducks and frogs?

May 13, 2023 7:19 AM

Wild ducks seem to have messed up my pond's ecosystem, and tadpoles are no more to be seen. I am a frog-lover. Can anything be done?

I live in a rural area on the coast of northeast England. My garden has a comically small pond, which used to be a regular spawning site for frogs. There were newts in there as well, and I spent many happy hours watching the fascinating pond creatures go about their business. Up until a few years ago, things were great, generations of tadpoles grew up and hopped off, and the pond seemed to be a healthy little ecosystem full of water-snails, water-fleas, water-beetles, and other things. The water was nice and clear.

Then several pairs of wild ducks turned up and started rearing broods of ducklings somewhere nearby, probably in a neighbour’s garden. This is a quiet road and people are mostly keen on wildlife, so we all tolerated them. Then the ducks started paddling around on my tiny pond, sometimes with their ducklings. They ate all the oxygenating plants, stirred up the water and generally made a horrible mess. Frogs arrived and spawned, but the spawn never hatched. I don’t know if the ducks ate it, or if the water quality became too poor to support life, or what.

By the autumn before last, the pond was devoid of water-snails, water-fleas and the other creatures that used to live there. I used one of those pond strips to test the water, but the results it gave were all in the normal range. I planted more oxygenating plants, but they also disappeared. The spawning has now failed for several years running (the frogs continue to spawn, but no tadpoles hatch).

Last autumn I bailed out most of the water and let the pond refill with rain over the winter. I tried covering the water with chicken wire, but that keeps out the frogs. I tried covering it with criss-crossing twine and bits of metal latticework tied together. The ducks just pushed it up at the side and wriggled in underneath. I have frequently chased them away, but they just come back later.

In terms of frog-friendly ecosystem viability, is my tiny pond now a lost cause? Am I correct in thinking the ducks are causing the problem? If so, there any effective way of keeping them off it? Obviously I have no intention of harming the ducks.

posted by Grunyon to Home & Garden (15 answers total)

I don’t know anything about ducks/ponds, but I might try putting chicken wire up a little further away from the pond - maybe like five feet back from the edge? And I’d make sure to get some with big enough holes that the frogs can fit through very easily - there’s a big enough size difference between frogs and ducks that you should be able to find something that’s no barrier for the frogs but keeps out the ducks.
posted by maleficent at 8:05 AM on May 13, 2023

I don't know whether ducks are the cause of your problems but you can definitely keep them out while letting frogs pass. How big of frogs are we talking? Building a cage out of say 4" welded or woven wire mesh that surrounds/ covers your pond should keep adult ducks out. But still allow free passage of adult frogs.

1/4 wire mesh (where the wire is 1/4" thick, spacing is greater) is strong enough you could build a quanset like cage to cover your pond that depending on size could be self supporting or need a minimal ridge beam.

Any sort of small opening mesh should also be able to be used, just don't extend it all the way to the ground. Frogs crawl under, ducks are kept out. Amphibians will often make use of culverts and other passages as well so a few short lengths of 4" PVC conduit providing passage thru an otherwise impenetrable mesh barrier may also be an approach.

Frogs can be sensitive to temperature. If your water temperature has been creeping up because of climate change digging a section deeper can help stabilize the temperature by increasing volume and providing coupling to consistent temperatures at deeper soil depths. They also need shady areas to hang out.

Conversely if climate change is freezing your pond over where previously that didn't happen that can also pact frogs who over winter in the water. Aeriation or a small floating heater can help there.

Finally some frogs need mud as part of their life cycle. If there used to be an intermittent mud hole or ditch someplace that got graded/developed away that may be your problem.
posted by Mitheral at 8:39 AM on May 13, 2023 [1 favorite]

Oh man, ducks.

I farmed in the part of the country that uses acequia / flood irrigation, and every damn time, I’d flood, the ducks would come, and bob their heads under water and eat a bunch on my starter crops. Ducks.

Consider digging your pond down another foot or two in a few places. Your general eco-collapse could be caused because the water’s median temperature is now too warm (climate change). The added depth will help meditate the increased surface temperature and allow your fish and amphibious buddies a greater range of temperatures to hang out in.

Perimeter fences won’t do much good in my experience, because the ducks will just fly over.

Depending on the size of your pond, something like this lattice fencing could be situated about 6-8” above the water level during duckling season and removed after.

Also consider half-burying short pieces of terra cotta or clay sewage/drainage pipes with one end opening to the pond. Toss is a selection of rocks. The pipes will provide refuge, cooling, and moisture for a wide variety of amphibians .

Not sure where you got your water plants from, but consider hiking to a local wild pond and taking some from there. Flora acclaimed to your exact region is going to have the best chance for reestablishing themselves after a collapse.

Your pond sounds delightful - best of luck in bringing it back!

Edit: also, do you have raccoons? Fish will usually take care of the duck poop just fine. Our pond collapsed after raccoons caught and ate most of our fish. Wasn’t much to be done about that, but we ended up re stocking with feeder fish from the pet store until we had a couple that managed to survive (again, there might be a native species that’s better suited for this).
posted by Silvery Fish at 9:04 AM on May 13, 2023 [3 favorites]

Fish will usually take care of the duck poop just fine. Our pond collapsed after raccoons caught and ate most of our fish. Wasn’t much to be done about that, but we ended up re stocking with feeder fish from the pet store until we had a couple that managed to survive (again, there might be a native species that’s better suited for this).

Fish are great, but make sure that you get a fish species that won't eat tadpoles.

Often tadpole safe fish are very very small fish, but check what's right for your local ecosystem.
posted by chariot pulled by cassowaries at 10:01 AM on May 13, 2023 [2 favorites]

Best answer: I dug a pond on my property in New England for my ducks. It was always a murky mess, as the ducks ate all the plants and creatures living in it. Once I stopped letting my ducks free range (damn you, murderous fisher cats) the pond started flourishing. The water is clean and full of salamanders, frogs and toads, as well as reeds and water plants. The ducks were too disruptive in so contained a habitat.

I think you might be ought of luck unless the ducks decide to move, unfortunately.
posted by lydhre at 11:06 AM on May 13, 2023

Response by poster: Many thanks for all advice so far. Um, I think everyone's overestimating the size of my pond. When I said it was comically small, I wasn't kidding.

Here is a link to an image of my comically small pond.

I saw ducklings swimming on it this morning, underneath that covering. You would hardly credit it.
posted by Grunyon at 11:11 AM on May 13, 2023 [8 favorites]

Mine’s maybe three times that. I’m thinking creatively here, could you build a chicken wire fence around it when it’s nesting season but cut in or bury some log tunnels for the frogs and newts?
posted by lydhre at 11:16 AM on May 13, 2023

My pal that is a puddle not a pond! Any way you can expand it? Anything that tiny is gonna be far less able to weather changes of any sort.
posted by showbiz_liz at 11:20 AM on May 13, 2023 [1 favorite]

Best answer: Ah, friend. I think we're in "how to deter ducks" territory. Want a dog? A sculpture of a dog?
posted by amtho at 11:56 AM on May 13, 2023

Best answer: ..Or, create a second, mesh covered areas for the little ones to spawn and hang out. It could be worth it if you can make it also attractive for you.
posted by amtho at 11:58 AM on May 13, 2023

Best answer: Some frogs breed in "vernal pools" which are dry part of the year. This assures there are no fish to eat them... but will it keep out ducks? Not sure.

You could try covering or removing/draining the pond for a while to see if the ducks lose interest. Ducks live a long time, though, so this seems unlikely to work.

I'm mentioning this to stimulate your own problem-solving imagination.
posted by amtho at 12:05 PM on May 13, 2023

Feels like a dome with frog-doors or frog sized mesh would be great.
posted by Iteki at 2:08 PM on May 13, 2023

Owl and coyote decoys will scare away ducks. Frogs won't mind.
posted by Toddles at 4:09 PM on May 13, 2023 [1 favorite]

As an example: in my state, the tadpole safe fish is

Pygmy Perch are a Western Australian native fish, which can generally tolerate water temperatures of between 0 and 25 degrees.

They are perfect for native frog ponds as they are too small to eat tadpoles, but are great at eating mosquito larvae, and small amounts of algae.
posted by chariot pulled by cassowaries at 10:48 PM on May 13, 2023

Best answer: One possibility would be to create one or more alternative ponds using something like a half barrel container. Like this.
posted by rongorongo at 4:40 AM on May 14, 2023