I have received many phone calls and inquiries from concerned persons on Grand Bahama Island with regards to re-occurring finds of dead birds on our beaches. I want to share with residents and visitors who have expressed concern and fear that the birds did not die from toxins, chemicals or avian flu.
Mr. Tony White, a board member of the American Birding Association who also conducts the annual Christmas Bird Count in Nassau and Grand Bahama, has provided me with an explanation which he received from a highly acclaimed seabird biologist in the United States, Dr. David Lee.
Lee states that the birds in question are Greater Shearwaters who spend their lives out at sea and a die-off occurs every few years. Most reports of dead birds come from Florida and the Carolina but due to winds and ocean currents birds have also been found in the Bahamas.
Greater Shearwaters nest and raise their young off the southern coasts off South America. When they are finished with feeding and raising their offspring they leave their breeding grounds for the Northern Hemisphere to spend the summer. The young birds remain at the nesting area, they are very fat and actually weigh more than their parents for a while. They start to exercise their wings and begin to fly and learn to feed themselves.
A few weeks later they follow their parents to the Grand Banks up north. Some years when there are no winds in the tropics the inexperienced young Shearwaters are unable to soar and find their feeding grounds. There is low fish productivity in the oxygen starved tropical waters and they are unable to feed. By the time they reach the Northern Hemisphere they are starved and exhausted. This is when high mortality occurs. All of the dead specimens that have been collected and studied from the Carolinas were immature birds and all had starved. This was determined by their light weight and emaciated breast bone.
There are an estimated five million pairs of this Shearwater species and the adults do not seem to be affected, either due to their earlier departure from the Southern Hemisphere when the tropical waters are cooler and more productive, or due to migratory experience.
Dr. Lee went on to say that this is not a disease or related to chemicals or toxins. He and other experts have published scientific papers on the subject several times, but that the media continues to say that scientists are unable to explain the die off.
