There are lots of ecological arguments for creating more green roofs, particularly in urban environments. Until now, though, I had never considered one additional benefit – certifying them as wildlife habitats.
I started thinking about this after reading an item on the S.W.I.M. Coalition website about the Christian Reformed Church in North America (CRCNA) of Grand Rapids, MI, that certified a recently-added green roof as a wildlife habitat. It turns out that this is pretty simple to do. To certify a wildlife habitat, you must provide:
“Planting native forbs, shrubs and trees is the easiest way to provide the foliage, nectar, pollen, berries, seeds and nuts that many species of wildlife require to survive and thrive. (You can also incorporate supplemental feeders and food sources).”
“Wildlife need clean water sources for many purposes, including drinking, bathing and reproduction. Water sources may include natural features such as ponds, lakes, rivers, springs, oceans and wetlands; or human-made features such as bird baths, puddling areas for butterflies, installed ponds or rain gardens.”
“Wildlife require places to hide in order to feel safe from people, predators and inclement weather. Use things like native vegetation, shrubs, thickets and brush piles or even dead trees.”
A place to raise young:
“Wildlife need a sheltered place to raise their offspring. Many places for cover can double as locations where wildlife can raise young, from wildflower meadows and bushes where many butterflies and moths lay their eggs, or caves where bats roost and form colonies.”
Many of these features, and in some cases all of them, are already naturally present on green roof designs. Even if they aren’t, they are fairly simple to incorporate if designers and clients choose to prioritize them.
The wildlife habitat certification program began in 1973 and has certified almost 150,000 habitats to date. You can see a complete list of registered sites, and communities, here. Oh, and they have a Flickr pool full of great photos.