When is comes to attracting wildlife the creation of a wildlife pond is right at the top of the list. Water is essential for life. Wildlife has evolved countless ways of exploiting all manner of water sources. Not only is it required for drinking but for many creatures it is essential for breeding and bathing. No wildlife can go very long without adequate access to water. Good wildlife pond design is therefore essential if you are to maximise all the effort and expense involved with building a pond.
It follows that any water is good for wildlife whether it is a washing up bowl ,as advocated by Chris Packham. or the construction of a vast inland waterway such as the Norfolk Broads. So how do we go about designing a wildlife pond that will meet all our requirements and attract the sort of wildlife that we are most interested in. Well the answer lies with a good understanding of the kind of wildlife that we most want to attract and how far we are prepared to create the right conditions. Most things are possible.
Given a choice it is invariably best to site the pond in an open and sunny position. A certain amount of shade is normally acceptable and maybe even beneficial but bear in mind that plants can always provide a certain level of shading themselves once they become established.
With regards to aesthics I always think that ponds blend in best when situated at the lowest part of a site. After all this is where water will naturally tend to accumulate whether we like it or not.
Some water is good but more is usually better. Generally speaking the larger the pond the better. (Probably best not to labour the point when discussing your plans with your spouse.) However, as all wildlife varies,each with their own unique requirements, it is often a good idea to start off small and add more ponds later. It is often a good idea to have several smaller ponds rather than one larger one. The key is to provide variation. Ponds naturally are a very dynamic habitats. The water level can vary drastically in the space of a few hours or even minutes. Many ponds dry out completely and this will obviously have a huge influence on the wildlife that exists.
In order to exploit the opportunities that appear pond life is often highly mobile and can travel by air or land to find new homes. This is great for the urban gardener who can be guaranteed that many forms of wildlife will find their creation without any further help. It is not necessary to stock from frogs,toads or newts and, of course, dragonflies, damselflies and birds will all readily find new water for drinking and bathing. However, conservation is nothing without management. Like it or now Man dominates the natural world , either directly through disturbance or indirectly through pollution and climate change. We therefore owe it to future generations to better understand what constitutes effective management. It is here where things start to get more interesting and exciting.
There is no need to over think the shape of a wildlife pond. It is normally best to make the best use of a liner and you won’t go far wrong with picking a conventional kidney shape. Bear in mind that plants grown around the pond edge can grow rapidly and will alter the shape and appearance of a pond making it appear smaller than when first installed. It is probably best to avoid long and thin shapes unless you plan a stream with a definite water flow. The edges are critical in the design. They should not be steep so as to allow creatures to readily enter and leave the pond. Many hedgehogs sadly drown in garden ponds. every year. If the pond is to blend in seemlessly with the surroundings unsightly exposures of liner should be avoided.
By now I hope you appreciate that variation is key. Ponds do not need to have a minimum depth to be of value. It is true that few plants or animals can withstand being frozen solid but water just an inch or two deep is indispensable for birds and many mammals. This spring frogs chose to spawn in one of my ponds that has a depth of less than 8 cm in preference to the adjacent one with varying depths to 80 cms. Reptiles, amphibians and fish all favour shallow water at certain times of the year. So one key requirement for most wildlife ponds is to have extensive shallow water areas. This is excellent news for parents as ponds can present a significant danger to toddlers and many lives are tragically lost every year. It also greatly reduces the amount of digging that is required.
Most people however would recognise that having a pond with a depth of at least 50 cms extends the range of wildlife that can be encouraged. Inevitably this occurs in the winter when metabolic rates are extremely low. As a consequence it is not necessary to have the same sized deep water areas as the shallows. In the middle of winter much pond life leads a fairly dormant existence and thrives on lack of disturbance.
In many situations my personal choice for deep water provision would be to have a second raised pond. These are much easier to install, as they require little or no digging. They are also safer with youg children. access can still be achieved with the use of ramps and it is easy to provide a small shallow water shelf for escaping wildlife or bathing birds. Leaves and runoff can be sources of pollution for ground level ponds but can be easily controlled if the pond is raised. Management is also easier with effortless drainage possible without the use of pumps. Plants can also be tended without the need for stooping.
Water quality is everything. Managing water quality is an essential feature of any wildlife pond. regretfully it is now virtually impossible to escape some form of air or water polltuion. It affects everything around us to some extent. Much wildlife is highly adaptable and is perfectly capable of withstanding this pollution. Sadly many of the rare species however are uniquely adapted to a specific habitat and cannot withstand any change.
Basically we have two choices when comes to water sources for ponds. Either we divert rainwater or we take it out of the tap. For no other reason than convenience tap water is usually the preferred source. It may well be the perfect choice but bear in mind that water companies are under no obligation to provide water that is safe for aquatic life. Indeed many companies inject chlorine to kill off all life and very effective it is too!. Fortunately this particular chemical is short lived and will naturally dispense over a 24 hour period. So lesson number one is do not stock a pond with anything for at least 24 hours and preferably longer. Lesson number two, if it is necessary to top up pond water levels in summer little and often is a much better plan than sudden large influxes of tapster. A better plan would be to pass all tap water through an activated carbon filter. These not only will remove the chlorine but will also remove heavy metals, pesticides and many other organic pollutants. As you are only replacing water lost by evaporation flow rates can be kept extremely low thereby reducing the size of the filer required.
I feel at this point I should also mention pond filters. Most wildlife pond advisors advocate that filters should not be installed. Although they are certainly not essential I do feel they can be of use. Not only do they improve water quality for the wildlife but when coupled with an ultraviolet filter they virtually guarantee clear water. A clear pond is generally much more appealing than pea soup. Although a balance between plants and wildlife will encourage clear water this cannot be guranteed. I shall return to this subject in much more detail in future postings but please bear in mind they they can add another dimension to wildlife ponds.
Well that about sums up the main considerations when thinking about a wildlife pond. Next I shall talk about the practicalities of constructing the pond.