Aug 14 2012
What’s wrong with this picture?
The trees are missing. And so are the birds.
Last week the University of Utah announced the results of a new study on bird diversity that compared intact tropical forest, agroforests, and open farmland. The result was not surprising: Birds do better in agroforests than on farms.
Agroforests are “a type of farm where the crops are grown under trees at a reasonable density,” according to study author Çağan H. Şekercioğlu. “Often, it’s not like forest-forest — it feels more like a open park.”
In the past, coffee and chocolate crops were both grown in agroforests — or in full tropical forest — because they are shade-loving plants.
But agri-business found even moderately shady habitat too labor intensive. Always on the lookout for ways to cut costs, they bred coffee bushes to tolerate full sun. For the past two decades they have cleared land, planted coffee in the sun, and harvested it mechanically.
Sadly, bird diversity drops as the habitat becomes more open. The study analyzed over 6,000 species and found that the more open the land, the fewer insect-eaters (flycatchers and warblers), fruit eaters (orioles and parrots), and nectar-eaters (hummingbirds). Agroforests can support many of these species but the study showed that open farmland supports only seed and grain eaters — and these birds are often considered pests.
Does open farmland south of the border affect “our” birds?
Yes. Most of our breeding forest birds are neotropical migrants who spend less than half their lives in North America. The majority of their time is spent in tropical forests — or agroforests — in Central and South America.
Every year there are fewer intact forests and fewer agroforests. Meanwhile many of our neotropical migrants are in decline including cerulean warblers and scarlet tanagers.
You can help. Your coffee is good for birds if it’s made in the shade.
How do you know if coffee is shade-grown?
Check the label for bird-friendly, shade-grown certification by a trustworthy environmental organization such as the Smithsonian Migratory Bird Center (SMBC) or the Rainforest Alliance. (Unfortunately some manufacturers have co-opted the term shade-grown because they know it’s worth more.)
Certified bird-friendly coffee and chocolate(!) aren’t always easy to find. If you have a favorite place to buy them, let us know by leaving a comment.
(photo by Fernando Rebêlo from Wikimedia Commons. Click on the image to see the original)
Click here for more on the University of Utah bird study.