Research news: What scientists are finding out about your yard.

Many FeederWatchers do much more than just put out feeders to attract birds – they sculpt their yards to be veritable bird sanctuaries (see article in 2011 Winter Bird Highlights).  In fact, landscaping your yard can be beneficial to both you and, your birds, and even your neighbors!

Researchers Susannah Lerman and Paige Warren¹ took a look at how native plantings affect bird diversity in Arizona.  The researchers quantified vegetation and conducted bird surveys in yards in the urban Phoenix area.  They found that natively landscaped yards increase the diversity of bird species found in an area. They also found that even a small number of native plantings can attract more bird species.

A Gray Catbird enjoys a native mulberry. Photo by FeederWatcher Errol Taskin from Shreveport, LA.

One scientific study by Gary Luck, Penny Davidson, Diane Boxall, and Lisa Smallbone² suggests that landscaping your yard isn’t just for the birds.  Naturally-landscaped yards make both you and your neighbors happier.  These researchers surveyed neighborhoods in several cities in Australia, and collected data on demographics, species diversity and richness, and vegetation cover.  Taking into account demographics, the researchers found that personal well-being as well as the well-being of the neighborhood were positively related to the diversity of birds and density of plants.

Well-landscaped yards also play an important role in creating effective wildlife corridors and networks in developed areas.  Hillary Rudd, Jamie Vala, and Valentin Schaefer³ found that a high number of green spaces are needed in urban areas in order to create a matrix to support bird pathways.  “Backyard habitat can be an invaluable food and habitat source for a wide range of urban species and is essential in developing the matrix that supports the large numbers of corridors required for connectivity.” Connectivity between green spaces (backyards, parks, and other natural areas) is important for allowing genetic diversity within species to flourish, as well as allowing birds to migrate within and through an area.  This research drives home the point that your backyard may be a key in creating a matrix of green spaces in your area.

We don’t have to study birds to know how landscaping affects them though; we can study their food sources!  Douglas Tallamy and Kimberley Shropshire⁴ studied larval Lepidopteran (caterpillar) use of native versus non-native plants.  The researchers found that native plants attracted four times as many species of Lepidoptera.  When the researchers compared just native and non-native ornamental plants, the native ornamentals attracted 15 times the number of species that non-native ornamentals did.  These differences have to do with co-evolution of plants and insects, human breeding of plants for insect resistance, and other factors.  But the bottom line is that native plants attract more yummy caterpillars for your birds to eat!

See FeederWatch’s page on landscaping or All About Birds’ section on landscaping for more on how to attract more birds to your yard or download the BirdNotes on gardening.

You can also learn lot’s more about landscaping for the birds in the pages of the soon-to-be launched new Cornell Lab of Ornithology Citizen Science project YardMap.  See YardMap’s Which Birds, Which Plants? tool.  (Keep an eye out for YardMap’s forthcoming launch or sign up for updates at yardmap.org!)

Or download NestWatch’s native plants for cavity nesting birds guide.

Sources:

1. Lerman, B., and Warren, P.S. (2011). The conservation value of residential yards: Linking birds and people. Ecological Applications, 21(4), 1317-1339.
2. Luck, G.W., Davidson, P., Boxall, D., & Smallbone, L. (2011). Relations between urban bird and plant communities and human well-being and connection to nature. Conservation Biology 25(4), 816-826.
3.  Rudd, H., Vala, J., & Schaefer, V. (2002). Importance of backyard habitat in a comprehensive biodiversity  conservation strategy: A connectivity analysis of urban green spaces. Restoration Ecology 10(2), 368-375.
4. Tallamy, D., and Shropshire, K. (2009). Ranking Leptidopteran use of native versus introduced plants. Conservation Biology. 23(4), 941-947