Autumn in the wildlife pond
- A loose heap of leaves is an ideal place for amphibians to over winter. Keep this heap collected in wire mesh so leaves do not blow back into the pond water.
- You could use a pond net to cover over the whole water area so no leaves can fall in but take care you do not trap frogs and hedgehogs in it.
- Providing log piles and homes for amphibians near the pond will be welcomed by many creatures as safe places to hide and overwinter.
When any horizontally growing and surface cover plants are removed from the pond in Autumn – check that you have not also removed wildlife creatures
- Dragonfly larvae spend several years under the water before emerging as adults and these larvae easily become removed from the water when you are removing plant growth.
- Late hatchings of newts can also still be in the pond and being only 1/2″ long can be difficult to spot.
- Backswimmers or Greater Water Boatmen will also become trapped if you collect armfuls or netfuls of plants in a mass.
Make sure you shake the plants you are removing over the pond to free the creatures – leaving the plants on the side of the pond is not sufficient – especially if you have twisted the plants or the blanketweed into a ball or tight clump – they need to be unravelled, opened out and shaken.
Leave oxygenating plants in the pond – do not thin out before Winter as the better oxygenated the pond in Winter the better it is for any wildlife that stays in the water. You can thin out in Spring.
Maintain oxygen levels in the pond in Winter
- In your garden pond you can try and reduce the likelihood of animal ‘winterkill’ by trying to maintain oxygen levels in the pond.
- Clear any fallen snow from the ice to ensure that the submerged plants can see light and be able to photosynthesize and produce oxygen.
- If you have a pump – leave this running over the winter as pushing the water back to the pond will help pump oxygen into the water.
Frogs, and sometimes newts, may lie dormant at the bottom of a pond in winter. In very icy winters frogs can die of ‘winterkill’ which occurs when toxic gases are released into the pond water through decomposition of dead leaves without sufficient oxygen to complete the process.
The water becomes deoxygenated in darkness ie under a blanket of snow across the pond surface the submerged oxygenating weed will not photosynthesize and there is a lack of oxygen and a build up of toxic gases in the water.
Seeing the frogs on the water surface in the thaw can be upsetting to pond-owners but this will only affect a very small percentage of the local frog population. By preparing the pond as carefully as possible in Autumn you will be doing your best to give them the best conditions you can.