Wildlife pond on a grander scale

[werdnal]

We are lucky enough to have a 1 acre field, in which we have always planned to install a large wildlife pond. We already have a garden pond, which we dug about 15 years ago, and has now matured, is full of amphibians and invertibrates, and visited daily by many birds to drink and bathe. This being so successful we are now planning to go large!

The field is fairly flat, and has a natural "basin" to one side, which is where we hope to excavate. Going to ask our friendly neigbouring farmer to borrow his JCB and pay a couple hours of his time to get the majority of the heavy digging done for us. Not sure of the eventual size yet, but evisage about 12-15ft diameter +. We are also lucky to have access to a natural spring, on the boundary of the next field, which we can pipe a portion of the water from to keep the pond topped up. We are hoping with the site being slightly lower than the surrounding land, and the addition of the natural water supply will be sufficient to keep the water level constant without a liner, which would be extortionately expensive. Ground is fairly clayey anyway, and when we dug our garden pond, it held a certain amount of water before the liner went in.

So, any advice before we embark on this project? Any do's and don't for doing a bigger version, or is it just a scale-up of what we've already done? Ideal minimum depth? - we don't want to go too mad, but obviously don't want it freezing either, although hoping that the flowing water might help prevent this anyway. Is there an ideal time to start to work, or will any time do? Anyone done anything similar and can give us a first hand experience please?

All advice welcome.

Thank you

[Dogghound]

Originally Posted by werdnal

So, any advice before we embark on this project? Any do's and don't for doing a bigger version, or is it just a scale-up of what we've already done? Ideal minimum depth? - we don't want to go too mad, but obviously don't want it freezing either, although hoping that the flowing water might help prevent this anyway. Is there an ideal time to start to work, or will any time do? Anyone done anything similar and can give us a first hand experience please?

Minimum depth 75cm in the centre I would go to about 150cm max. You should aim to create wide shallow margins. Allowing the water level to drop through the summer but keep a deeper area which retains water in the centre. I would avoid flowing water too. The time of work depends on the habitat your creating the pond in, will it cause isssues to breeding birds? or amphibians or mammals etc. Large parts of my job involve pond creation plans ive done loads, one very similar last week infact so I can give you advice on them. Also consider terrestrial habitat too, you want an area as large as the pond or larger of rough grassland/scrub around it. This should be linked to other good habitat like hedgerows or woodland or meadow.

Its sometimes easier to aim the project at a particular group of species too.

[Cowgirl]

Ooo you're so lucky, our garden pond is 16' x 10'....what I would do with a JCB & an acre of land, , gwaan, go larger! 'less of course you're having to buy a liner

Make the most of that JCB. Good luck

ps Dogghound's always right I wish I'd created wider shallower margins, mine are too deep & I have all my plants propped up on rocks so they're not planted too deep. One day I'll be to afford to buy a load of rocks/bricks & infill the margins with gravel/soil.

[Ukwildlifeo]

One idea could be a pond as dogghound suggests, but also perhaps a smaller, shallower pond too, even one that dries out some summers as this is another type of habitat too, which will benefit another group of animals.

Keeping the pond free of fish will also be beneficial for the insects and amphibians.

Sound like a great project

[Dogghound]

Yes good point dont add fish or wildfowl. Avoid islands as you will then get nesting mallard on a pond of this size which will reduce the water quality. A pair of moorhens would not be a problem. Its possible to create smaller pools in the margins by raising sections from the bank creating shallow pools, which dry out through the summer. The margins will create an area for birds like tree sparrows/reed buntings to feed and birds like swallows to collect nesting material.

[Cowgirl]

Originally Posted by Ukwildlifeo

but also perhaps a smaller, shallower pond too, even one that dries out some summers as this is another type of habitat too, which will benefit another group of animals.

Am curious, what do you mean, what sort of animals? There's one of those just up the road from me, well I say pond, it's mostly a smallish damp hole in a wood that fills with water in the autumn/winter, but dries out by late spring/summer (dried now). Always felt sorry for any frogs/toads that decided to spawn there.

[Ukwildlifeo]

Originally Posted by Cowgirl

Am curious, what do you mean, what sort of animals? There's one of those just up the road from me, well I say pond, it's mostly a smallish damp hole in a wood that fills with water in the autumn/winter, but dries out by late spring/summer (dried now). Always felt sorry for any frogs/toads that decided to spawn there.

These ponds that dry out in summer will stop the eventually colonisation by fish (eggs on birds feet etc) which is good news for amphibians and invertebrates.

But also it favours those species which can live in and often are specialised to these sorts of ponds. One example is Scarce emerald damselfly and whose eggs can survive drying out in late summer early autumn when water levels are at their lowest and hatch in spring, taking only 6 weeks to go from egg to adult in a pond free from most competition and predators. A couple of other dragonfly species like the ruddy darter can colonise these pools too and other creatures like water boatmen fly in as adult in spring, breed and their young have time to develop into adults and can fly out as the pond dries out.

Going back to the amphibians, some years the pond will hold water long enough for at least some of the tadpoles to fully develop, again with the advantage of a pond with less predators and competition.

Sorry to wander slightly off topic but it does present a case for shallow ponds. I would have is seperate from the main pond to prevent colonisation from the permanant/deep pond.

[werdnal]

Thanks for replies to date. We were sort of thinking of a natural "saucer" shape, rather than a shelved pond like the one we have in our garden. The edges will taper off into the existing field grass. We do have a mixed habitat, with half the field fenced off from our animals, giving an untouched rough grass area with an abundant of wildflowers. The pond will be on the edge of this area. We do not intend to have fish at all.

The "flowing" water was the reference to the natural spring, which we intend to tap into for a top up source. There will be no actual current noticeable, but we expect the pond to overflow into the margin to create a boggy area. Our garden pond is spring fed, and the overflow creates a small stream through our garden, which runs into a culvert and eventually into a natural stream, which is the early stages of the river Fal. Because of this our existing pond never freezes, and we hope the same will apply to the larger one.

Should we think about planting it with natives, or leave it bare and see what colonises naturally?

[King Edward]

Consider ordering this book: The Pond Book from Pond Conservation. I bought it recently and have been finding it very useful. There is a lot of good information on their website as well.

Also it would be worth checking the nutrient levels in the spring water, as it could well have high nutrient levels which would adversely affect the pond.

As you're planning an unlined pond, consider excavating the pond in two stages - first to get the general depth and shape, then see how the water levels change over a year or so. Armed with that knowledge, you can then excavate the margins to create good areas of shallow water with varied depth, part of which would dry out somewhat during the summer. Since your neighbour has the JCB, it hopefully shouldn't be a problem to borrow it twice.

4-5m across isn't all that big a pond, so I don't think you'd want to be going anything like 1.5m down unless perhaps you were expecting a really big drop in summer - 75cm should be plenty, and even with that depth it could be difficult to get adequate shallow areas without very steep slopes.

[dampflippers]

Pond Conservation | Million Ponds | Million Ponds Project

Pond Conservation | Million Ponds | Pond Creation Toolkit

Spend a valuable few minutes or hours looking at the Million Ponds project resources.
They recommend a network of several ponds and scrapes or different sizes, dug without using liners. They also recommend not planting them up, but that is up to you.

Grants may be available, but these only pay for digger hire, so you are probably better just paying your farmer for use of his.

Hope it goes well.