Building a pond for wildlife observation - Tips and ideas?

[jhbratton]

My experience of ponds is in the UK so things will be different in a much warmer place, but here are a few things to consider.

Try to keep the nutrient levels in the water low. The more fertile it is, the more likely you are to get swamped by a few fast-growing species, especially microscopic algae. These will go through cycles of fast growth then death, decomposition releasing nutrients, then another cycle of fast growth and death. Adding organic matter will raise the nutrient levels. Your tap water might be high in nitrates.

I wouldn’t put a tree on the island. It will drop its leaves in the pond and they will add to the nutrients, and their decomposition will reduce the oxygen. But I can see you might want to provide shade to stop the water getting too warm (warmer water holds less oxygen).

I would avoid putting in predatory fish because in such a small pond they could wipe out many of the invertebrates. You might think they will strike a natural balance, but the most likely balance would be a few hungry fish subsisting on every insect and amphibian that drops in.

Ponds that dry out can be just as interesting as ponds that stay permanently full. They will be dominated by species with a short life cycle and a resting stage or a stage that can cope with dry conditions.

It is good that you don’t need an artificial liner. The zone around the water edge is critical for many insects, and if that zone is a sheet of plastic it is rather inhospitable.

[abrub]

Thanks for the info! I’ll be keeping an eye out for what happens in the ditches around the area as summer progresses. So far I have noticed an increase in algae, but its a different type than the one in my pond. I haven’t added rocks just yet, but I’ll look into it. I think the deepest part of the pond is somewhere around 60-80 cm, because the dirt got very hard after the initial 30cm or so.
The cattails are doing pretty well actually, all but one seem to have taken well to the pond, but only time will tell if they stick around or not.
Would adding dry leaves and grass to the exposed areas of the pond protect them? Or do you think it needs to be sticks and rocks since those won’t move as much if it gets filled up again?

[jhbratton]

I’m not sure what you mean by exposed areas of the pond. Do you mean the edges above water level, or bare areas of the pond bottom? I wouldn’t add grass and leaves to the water. And I reckon bare areas around the edge above water will be colonised by plants of some sort just by seeds blowing in. Or are you worried that bare steep edges will slump and make the pond shallower? If so, I guess it will find a stable shape. I reckon cattails (= Typha ?) will fill the pond in a couple of summers. That would still give you an interesting patch of habitat, but a marsh rather than a pond.

[NancyinSunnyvale]

Good for you, building a wildlife pond.

I have no personal experience, but Kathy Biggs, a California-based Odonata expert, has a lot of pond-building advice on her website. Check out https://southwestdragonflies.net/Pond/

[scottwgavins]

Regarding protecting exposed areas. It will be much easier if they are not steep. Unless you can get good vegetation cover. Whether covered in water or not the organic matter will be moved slowly down hill. Leaflitter etc can be helped stay put by some plants or it may need some sticks that kind of act as scaffold. Leaflitter etch with sticks over it is a easy way to apply it. Exposed leaflitter should get weighed down by the rain as the pond fills. Exposed sticks may float (at least for a short while) as the pond fills so be sure there is some bulk of sticks that stays above the water level to weigh them down and anchors them to the edge. Such as long branches with the heavy end up on the bank. A thick tangle of sticks is good habitat.
I still have a plenty of places where plants are yet to colonise on my dam wall and as these places are exposed each year I put down sugarcane mulch (which is cheap where I am). It is much like leaflitter but also ling so it tangles together better and stays put longer. As time goes on I need less and less.
You may find the pasture grass that surrounds your pond will grow to be a thick covering around the edge and somewhat into the water.

[abrub]

Yeah I meant the areas that get exposed as water level decreases, essentially the “walls” of the pond. I will probably remove some cattails if they start to colonize, because I’d rather keep different enviroments and I think cattails on one side and just water on the other would work nicely.

[abrub]

Oh that is some amazing info! Thank you very much!!

[cassieguan]

Been following this for a while, not too sure how relevant this is but I do have some experience using outdoor fish tanks like ponds.

What I did was take water, soil and plants from an actual local pond, came with a few interesting creatures as well, and put them in the tanks. From there, I’d typically let the rain replace and overflow the tanks with excess water draining to the garden or porch, occasionally but rarely with filtered and dechlorinated water (was a little paranoid over the water quality though)
The plants were pretty much all Hydrillas though, and I did not add any other type.
The tanks were not filtered, nor were they thermo-controlled (I live in a tropical country).

Left in those conditions for about a month in, and there was clear growth with the Hydrilla, as well as some algae. No cyanobacteria blooms. There were two types of snails, one of them was wiped out by factors I don’t actually know.
Several different animals also started showing up. There were toad tadpoles in one of the tanks, they preferred shallower water. There were mosquitoes and other insects. When the water levels rose too much, dragonflies started laying eggs there, the nymphs will occasionally grab a tadpole or mosquito larvae. The tadpoles depended on the algae to survive, so when the algae disappeared at one point they started starving, had to introduce algae from one of the other tanks.

I had put two different types of fish in the tanks as well, one being Betta genus fish, and the other guppies, Poecilia reticulata, which have become naturalised in my area.
They actually thrived, with the guppies actually requiring minimal manual feeding. Seem to have been eating the algae as the amount of algae was less than the tank with the Bettas. They also ate other invertebrates in the area, and eventually the Bettas ate almost all the snails in their tanks. They still was a fairly balanced population of animals on the guppy tanks however, and they bred a lot. The young or small guppies were also occasional targets for dragonflies and their nymphs. Small red worms (blood worms?), Daphnia and yet more worms were found, as well as lots of other microscopic fauna. Even the Bettas had them, despite eating them, they haven’t actually eaten everything up. Maybe that’s due to me manually feeding them though, I do not know.

It has been a few years now, the tanks are still there, though more or less appear as more of normal styled Walstad tanks at this point, haha
I’ve actually experienced decomposition first hand in those tanks, was a little sad but was also really interesting.
Snails went first, eating the eyes and belly of the fish, followed by the worms and other creatures. Sometimes, the body doesn’t float either, I’ve yet to conclude why so, however. Afterwards, the animal decomposes over time, leaving bones that are promptly covered in algae. Lots of plants will start blooming, and gas bubbles of what I believe is ammonia would get trapped.
If there are other fish in the area, they may start feasting on the corpse, sometimes even guarding it from would be food thieves. They are the same species of fish though, I’ve seen the “children” eating their parents, good grief.

All in all, it’s a very interesting and eye opening experience, it’s unfortunate I haven’t a place for a pond myself but it’s incredible how all manner of creatures would suddenly appear, and to see full life cycles.
All the best with the pond though! I’d love to know what stuff may occur there.

[abrub]

Hi, I appreciate all comments and advice, regardless of how “relevant” or not it might seem to you, all info helps me out a lot!
I did not make another update this weekend cause it rained a lot, so I wasn’t able to go visit the pond (although im guessing all that rainwater will be great for it).

Was your fishtank partially or fully buried like im picturing, or was it just standing in your yard/garden? It is an interesting idea for sure, but I doubt I will implement it in the near future. Maybe if I ever move to a small appartment it would be fun to have a mini pond there.
I wonder tho, here it is somewhat common for glass bottles and such to cause fires in the fields, is it possible that a “fishtank” pond may have the same effect at times? Specially if water levels fluctuate and a good portion of the glass is exposed. I also would worry about pressure from the dirt around it or any outside sources like hail causing the glass to break? Maybe that is a bit silly though, since fishtanks are made of sturdy glass, but I’d rather ask anyway.

With some luck I’ll visit the pond again this weekend, would you like to keep recieving updates? I was thinking folks were probably not interested anymore, since the basic setup is done and the post has been really quiet since the last time I talked about the pond.

[teellbee]

You did a pretty thorough observation and good job keeping track of the evolution of your tanks… it’s pretty amazing to see how such an environment changes and adapts, even if we don’t always completely understand why it all happens.

[teellbee]

I am looking forward to reading about updates from the evolution of your pond, too.

When I moved into my place years back, there was an established, though not well planned, “koi” pond. For one thing, it was too small (4’Wx5’Lx4’D) for the big fish. It had a biological filter and circulating pump. After noticing the fish gulping at the surface for a long time, I finally figured out they needed more oxygen and added air stones.

I had to clean the filter manually and that wastewater produced THE BEST garden fertilizer ever!

Also, when I needed samples of water with microscopic life to show the kids at the Nature Center, I got far, far, better collections of critters from my little pond than sampling the local man-made lake (yet it supported lots of fish, birds, plants, etc.).

I loved that little pond, but in time it was too much physically to deal with. I got a lemon tree instead. And, it’s nice to have a lemon tree. But, not as interesting as the pond.

[dianastuder]

We have a lemon tree, and a small pond. Your garden wildlife must miss the pond?

[teellbee]

We do miss the pond, though it’s just a small patio garden. I imagine the raccoon that had started frequently raiding the fish missed it, too.

[abrub]

Here’s a bit of an update since I’ve been quiet for a while.

-Very good news! I’ve gotten permission to make the pond bigger. I have already dug up an extra hole as deep as I could. I think it’s around 75-90 cm, which might not be too impressive but let me tell you, it was hard work digging it by myself! The dirt gets super hard around the 40 cm mark, but after that it becomes more bearable. My dog also wanted to help, so she dug quite a bit as well (although somehow she manages to keep her nails really sharp even with all that digging).

-I added small rocks and stones to the bottom of the hole before connecting it to the pond. Im not super sure that it will work, but I hope that varying the conditions of the bottom help create more defined and diverse mini-habitats.

-On the subject of digging, I leveled the “island” quite a bit, and made a ramp to allow any potential wildlife to comfortably climb on it if they want to.

-I’ve seen some of Kathy Biggs’ videos on pond building, so following her advice I will be adding a “beach” of sorts in the other side of the pond. Im not sure if I should use sand for it or just plain ol’ rocks just yet. I’ll likely be working on this during the next weekend or so, so expect updates on that!

-Quite a few of the plants that I added 2 weeks ago are half-dead, but I’ll take that as a win because it’s way better than them being fully dead. I think as long as im stubborn and keep planting new stuff eventually something will catch on.

-There is sadly a lot of algae in the pond, not only of the bigger, easy to take out kind, but lots of superficial ones that form a sort of “layer” on top of the water. There was quite a lot of green bubbles comming from the bottom of the pond. Should I worry about this? I don’t want algae to take over, but I don’t know of any organism that feeds on it around here.

-Lots of animals seem to be coming to take a drink and find food around the pond. I found a set of what I believe are hare tracks, and while I was quietly sitting near the edge I saw two pampean cavies enter through the bottom of the fence and start feeding on the short grass nearby. They must have been at 3 or 4 metres away from me.

-The mockingbirds keep associating me with food so they come close as soon as they spot me. It’s amazing to just sit still and watch their behavior. They manage to be incredibly social and very territorial at the same time. Some kiskadees and horneros also came to eat, but they are nowere near as confident that im not a scary predator, so they stay back. Then there’s the picazuro pigeons. As big as they are, they fly away as soon as they see me aproach. Still, once I leave for a bit they perch on the fence near the pond and just hang out. I have not seen any bird come down to drink, but it is clear that they enjoy the pond very much.

-I have also noticed quite a lot of mosquito’s and their larvae. I had written off adding fish since you guys said they would eat everything, but this makes me want to reconsider. The fish (Austrolebias bellottii) are less than an inch in size when fully grown, so I don’t know if they would be that much of a threat to thing like tadpoles and dragonfly larvae.

-The weather has been althernating between rainy and cloudy this last week and will continue like that for at least one more. The cold temperature means I don’t have to worry about the water level dropping much, but I’ll likely have to add more water the next time I visit.

Lastly, here are some pictures I took:

This is the hole. The shovel is at around 40cm, since it gets progressively deeper.

My dog Pizza, helping with the digging.

This is how it looked like right before I connected it to the rest of the pond.

And here’s the moment it was finally connected (I had to convert the video to .gif for iNat to let me upload it, sorry if it looks too small)

That’s all for now!

[twan3253]

Thanks for sharing your amazing progress with us! Keep up the good work :)

[dianastuder]

Your pond needs time to settle and find its own stability.
For the bubbly green algae on the surface - something like a hand tool for leaf-raking - to skim that excess off. Then mulch it onto a ‘flower’ bed.
It will come right.

[leif]

This is a great idea. If I were building a pond like this, I’d want to add some fairly large rocks at one end. This would provide some diversity to the microhabitats, and might help to stabilize the bank. I’d definitely want to add something to sit on, perhaps a stump or log, so you can spend long periods observing. Good luck with it, and keep us updated with photos!

[scottwgavins]

I expect the gravel to get quickly completely covered with mud. Gravel might work in a fish tank or concrete pond but it’s not much use in one made of dirt. Unless it is used on a bank. The natural progression of lagoons is to silt up. This is assuming that they don’t get scoured out from turbulent water washing over them from time to time. I would expect that one year after making a pond like this that the bottom will be covered with a layer of organic matter mixed with silt. The deep sump parts can be a good place for the extra silt to collect rather than it reducing the depth of the whole pond. Also deep sump type things can provide a final last bit of water as a refuge when things get really dry. If they are deep they can also be a refuge against wading birds that can’t wade in water that deep.
Adding tiny fish might work. Be sure they are native so that nature has a chance to keep them in check.

[abrub]

Sorry for being so silent everyone! The weather has been pretty crazy lately and has fluctuated between terrible heat to constant rain, so I haven’t been able to visit the pond for a few weeks. I went today tho, after all the rains and was amazed at what i saw! Here’s the rundown:

-The water level was very good, all that rain meant all the plants and animals had plenty of water to go around, there was even some water spilling from the pond to the nearby soil.

-The algae seem to be mostly under control now, a few patches of that darker, more “classic” looking algae here and there but nothing bad.

-The plants are doing pretty great, specially the emergent vegetation. There’s lots of “water clovers” floating around and looking gorgeous.

-There is also an insane amount of frogs and toads now (as well as a few ant colonies that are trying to set up shop near the shore, not sure why tho). We’re starting to drain the pool, so any amphibian I find there gets promptly captured and moved to the pond to start a new happy life. It’s either that or the roadside ditches, and those don’t have nearly as much water. I’ve seen quite a few eggs of what I think are Leptodactylus latrans, as well as some unknown white eggs on top of one of the logs by the shore. If anyone can help me identify those I would be very grateful! I’ve also seen a single tadpole chilling in the pond as well, so it has certainly become quite the hotspot for the frogs to hang out in.

-Sadly not all animals are as nice as the frogs. I have been noticing a lot of european starlings (Sturnus vulgaris). They are an invasive species here, and compete with our native birds for food and nest sites. They are also recorded stealing nests from horneros (Furnarius rufus). I am looking up ways to legally cull them, if not to minimize their population at least to discourage them from coming here. I have also personally seen them fight with the mockingbirds, so I feel like now it’s a personal fight haha.

-Considering how much fauna is living in the pond at the moment, I’ve decided to halt the building of the “beach”. Perhaps I will do it once the frog eggs are hatched, or I will wait until autumn, im not sure just yet.

-Lastly, I’ve seen someone else in the forum do a post similar to these, but with the renovation of a bank. Instead of posting updates in the forum, they made a proyect of sorts (?) where they post updates. Should I make something similar? It might be less bothersome for everyone if I do, although im not sure exactly what it’s called (I don’t think its a proyect, it had a different name I believe). If anyone knows what it is and how I can make it (or weather its a bad idea to change format for the updates) I’d be very thankful to know!

Sorry the pictures aren’t as good this time! I forgor to snap some pics until the sun had already gone down and we were about to leave, so it’s hard to see all the plants’ brighter colors, but I asure you, they are looking great!