Permanent ponds

Permanent ponds

Ponds are one of the most important wet features you can have on an arable farm.

What

A vast array of wildlife will gravitate towards a good quality farm pond. Permanent ponds hold water all year round, providing permanent habitat for a range of wildlife as well as a many occasional or periodic visitors.

Farm pond 2 Chris Tomson

Why

Ponds can be a forgotten or neglected part of the farm, and often overlooked in favour of other environmental options. A huge variety of wildlife relies on ponds having  three key features: clean water, shallow margins and good plant life. The sheer diversity of species which use ponds makes them an exciting and essential part of the landscape.

Healthy ponds can support a huge number of marginal and aquatic plants, including once common plants like marsh marigold and water crowfoot. Aquatic invertebrates can thrive in ponds, including dragonflies whose larvae are dependent on ponds. Beneficial insects such as bees will drink from ponds while many hoverflies, one of our key wild pollinators, need water to complete their lifecycle. Amphibians rely on ponds for breeding, and grass snakes are strongly associated with ponds (and other wetlands), as they prey on frogs, toads and newts. Birds and mammals in arable areas often rely on ponds for their drinking water.

Ponds (other than temporary ponds or scrapes) may dry out periodically, or in drought years. This characteristic helps to eradicate fish, if they have been introduced.

The protection and management of ponds, and where it’s appropriate the creation of new ponds, is incredibly important. One of the key parts of this is appropriate buffering of the ponds to protect them from run-off and pollutants, and where this isn’t an option, creation of new ponds as opposed to the management of old ponds, can be the most effective route for wildlife ponds in farmland.

The habitat immediately surrounding ponds is especially important and should provide structure, such as in the form of rough grassland used for feeding and shelter for amphibians. Log or stone piles close to the ponds can be valuable features for a wide range of wildlife. Ponds should be connected to other important habitat on the farm and the wider environment. Hedgerows and buffer strips can be important in enabling species to move between habitats, including other ponds, woodland, scrub and tussocky grassland to find areas to feed, migrate, take refuge and hibernate.

Grass snake Natrix natrix, swimming, RSPB Rainham Marshes, Essex, England, August

How

Clean water is a vital part of a healthy pond – many of the species that rely on ponds cannot survive in very nutrient rich or polluted water. Buffering ponds in arable areas is therefore essential, and ideally the buffer around an arable pond should be at least 12m. If the ponds on your farm have historically been used for cleaning water through silt collection it is worth considering creating a new pond complex for wildlife and keeping any settling ponds for that purpose. The best place to site ponds is in permanent pasture, however a wide buffer strip planted up with a mixture of robust grasses will mimic this habitat, providing the grassy margins that benefit amphibians, especially newts and toads, as the migrate to and from different water bodies.

The best ponds are often those in full sun, with shallow margins and a varied topography under the surface. These provide the widest variety of marginal and aquatic plant life. Wide (about 50-60cm wide) and shallow margins (about 5-15cm deep), with a shelved profile into a central deeper well area of about 1.5m will provide the most benefit for wildlife. By providing a complex of smaller ponds, as opposed to one big pond, you add additional value to the feature as each pond can be slightly different to cater for a wider range of species, and by having several ponds in a complex, a measure of safety is built into the feature, as if something happens to one pond, the others provides a refuge until it can be rectified.

When creating a new pond the temptation is to plant it up, however natural regeneration is by far the easiest way to develop pond wildlife, not only that, but stocking ponds increases the chances of bringing in invasive non-native (pest)  plants. Surface invertebrates like pond skaters, whirligig beetles and water boatmen will usually find a pond within a few weeks. Marginal and aquatic plants will arrive in a few months, generally on the feet of an obliging water bird. It can take up to a year, but at the end of that time the new pond will look very much like it has been there all along. It is important not to introduce fish and wildfowl to ponds, as this will have an impact on the number of invertebrates and reduce the suitability of the ponds for many amphibians. The larvae of great crested newts are particularly vulnerable to predation by fish and are rarely found where fish are present in ponds.

There isn’t a good time to do pond management, however this should be typically undertaken between 1st November and 31st January inclusive.

Although there isn’t much management needed to maintain a pond there are a few things to keep an eye on:

  • Invasive aquatic plants can sometimes appear in new ponds, so its worth keeping an eye out for the worst offenders New Zealand pigmy weed and Parrots Feather. These need to be pulled out as soon as possible as both are capable of taking over a pond completely in a short space of time.
  • If scrub starts to develop around the  pond its worth managing it so it doesn’t shade the pond out – although some dappled shade is good, keeping the pond open and sunny is very important. It can often be a balancing act to retain good terrestrial habitat (such as that provided by trees and scrub) and to keep ponds open. A good compromise is to retain trees on the northern side of the pond, but keeping the southern perimeter open.
  • Reedmace and common reed can often colonise ponds, and they can be very invasive, swiftly out competing other plants particularly in small ponds. It may be necessary to remove both to encourage a diverse pond community, but should be undertaken sensitively and not all in one season.
OLYMPUS DIGITAL CAMERA

More information

You can find more detailed information on creating wildlife ponds at the Freshwater Habitats Trusts pond clinic

If you farm in Scotland, you may find this information on creating ponds useful

In practice

Here are some useful case studies and articles about how farmers are putting Farm Wildlife into practice on their farms

There are no relevant Case Studies yet