I am grateful that the woods around my house are suitable for tanagers. This bright sprite of a bird outshines all the local competition. This week I got several reports of a new tanager foraging behavior. I am not sure if it is one bird or several as this has been seen now at 5 of my neighbors homes and also mine. The tanagers have figured out that the skylights on covered porches make nifty bug traps. And while the bird is there it can also scan the porch ceiling for European paper wasps nests. They knock the nest down and pull out the larva, stack them in a pile then pick up a mouthful to feed to their kids. A few years ago I counted 12 nests on my front porch, now there are none, I checked with some neighbors and they too have none, and have noticed the bits of paper lying about. This might be an interesting example of how a learned behavior affects the ecology of my garden. If this adult tanager can pass this trick to its offspring, then the local population of paper wasp might drop. Since the wasp puts a caterpillar in each nest cell to feed its larva once the eggs hatch, less wasps equals more caterpillars. More caterpillars equals more cabbage white butterflies which lay their eggs on my broccoli. So a new behavior in a tanager means less fresh broccoli for me. Since the phyto-nutrients in broccoli are especially good at fortifying the human body against cancer, my potential life span declines. Huh? Yikes maybe I am not so grateful that Tanagers share my yard.



Rob Sandelin,

Pondering consequences in

South Snohomish County