Last week during a bat survey, watching common and soprano pipistrelles streaming through a private garden, it occurred to me (not for the first time) how undervalued gardens can be for ecology in the UK.
Despite the fact that private gardens account for an estimated area equivalent to one-fifth of Wales, there is no national guidance to help with assessing their value.
In fact, I haven’t been able to find much that encourages us to make assessments of value in any meaningful way. This is particularly relevant to ecologists, as often gardens, or similar managed greenspace, form part of proposed development sites.
For example, many surveys of properties for bats involve looking at the building surroundings, as we make a judgement about potential foraging and commuting habitats.
Changing views
Fifty years ago in the middle of the 20th century, there was a widespread belief that gardens, highly managed and dominated by alien plants, provided few resources for native animals. Since that time, it has gradually become clear that the value of urban gardens for biodiversity may actually be substantial.
Some species, once common in low-intensity farmland, are now more abundant in urban areas, and particularly in domestic gardens. For bird species such as dunnock, song thrush and bullfinch, urban gardens support a significant fraction of the total UK population, providing valuable habitat and foraging resources. Even species such as the tree sparrow and starling in the image below can be conserved by supplementing their food in gardens. We have a small but thriving, colony of tree sparrows in the garden at home, partly as a result of putting out food on a daily basis.
Valuing gardens
So, how should we rate gardens from an ecological point of view? A simple way to start is to look for positive features (attributes) that we can find in gardens, and to use these to build up a picture of value. It is tempting to score these features to give a numeric value, but this can lead to over-simplification and possibly even to devaluing some features. For example, one compost heap or log pile may be quite different from another, particularly when found in combination with other important ecological features.
Just recognising and stating that some things have value is sensible and pragmatic approach, with much to commend it.
Positive features (attributes)
Almost anything which provides an ecological element in a garden can be regarded as a positive feature. The trick is to recognise the ecological benefit in each case (and to be bold enough to say what it is). For example, something as simple as having unmown grass will create a more diverse range of structural features at any time of year than a regularly mown sward. You only need to get down to ground level or use a sweep net to see the range of species. And there are other benefits such as conservation of soil moisture and temperature benefits.
Why not have a think about garden values and attributes in your own garden during the lockdown? It is sometimes surprising what you can find, and what occurs to you when you have a bit more thinking time than usual.
As always, if you would like our advice and support for any aspect of your work, including garden surveys and assessments, please get in touch.
If you are involved in a development project, we can provide expert guidance and undertake habitat and protected species surveys and assessments.
If you are an ecologist, we offer 1-1 and small group mentoring, as well as formal training, both face to face and via webinars.