Wednesday, June 15, 2016



Every Spring we are serenaded by mourning doves, cardinals, robins, mockingbirds, wrens  and other song birds as they prepare for the spring mating season.  Humans get an emotional boost when birds begin singing in the early Spring  because they know the weather will get warmer; and the vegetation will start to grow and everything will begin to green-up.

Recent fossil discoveries in China have found that not all of the dinosaurs died out in the big meteor strike about 65 million years ago.  Modern birds are descended from a flying feathered dinosaur that some how survived the disaster. Why did they survive when so many other species became extinct within a very short time?  Being small, mobile and warm blooded probably helped.

Bird song is interpreted by us as a pleasant experience, but for birds it is part of a threat display that is anything but pleasant.  If you translated a robin's song into English you probably could not print it or say it on TV. The male robin who arrives on site first uses his beautiful song to create a "wall" between himself and other male robins in the area.  Unlike humans who create actual walls, fences and hedges to separate themselves from their neighbors, the robin's wall is invisible. If you doubt this just watch the birds for awhile as they chase each other back and forth  until they agree on the boundary. Once the territory boundaries  are  defined the female robin will join her mate and they will get down to business.

In most bird species the female builds a nest while  the male stands guard. Each kind of bird has its own technique in nest building. The behavior is instinctive, meaning the steps followed are programed into the bird's tiny brain. The choice of  location, materials used and the procedures followed are all set in this animal's DNA. As remarkable as it may seem robins, cardinals and Baltimore orioles will make a nest exactly like the one they were born in, even without ever having seen one. The oriole weaves a bag-like nest that hangs from a branch that must weather rain, heat and wind as it holds mother and young for more than a month. And she does this with a beak and two feet. I challenge any human who has seen such a nest to create one with just your fingers---you can not do it.

Once the chicks hatch, typically both parents carry food to the nest.  Why do they go to all this work to care for their offspring? Love? To make sure their children grow up to be good productive citizens in bird society?  Not really. If you look in a nest you will see baby birds open their mouths in anticipation of food. A scientist once placed  a test-tube painted with the same color as the birds mouth in a nest.  The result---the parents filled the test-tube with worms. When the baby opens its brightly colored mouth this is a signal "Mom,  go get food".  If it is cold, wet or the babies do not feel well they will not open their beaks and the parents stop bringing food---result is death to the young.  This Spring was cold and wet; and when I monitored some bluebird boxes, I discovered several young bluebirds dead in the boxes. Absent a signal, their parents had simply stopped feeding them.

The flying dinosaurs  living in our landscapes are beautiful, fascinating creatures that have managed to survive for millions of years.  They certainly brighten our lives with their songs, their wide variety of colors and their fascinating behavior.  If you do not have these creatures visiting your yard on a regular basis, adding native shrubs and trees  to the landscape will provide the habitat they look for each Spring as they prepare to keep their species going.

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