delight Louisiana birders
By Jay V.
|Most of you have never heard
of a bird called a booby unless you've read about
castaways surviving ship wrecks by catching and eating
boobies that landed on their life boats or life rafts.
They are rare birds in our region of the world. So, when
three Brown Boobies showed up in mid-October in Calcasieu
Lake just offshore from the tiny community of Big Lake,
birders "flocked" to the area to add the bird
to their life lists!
Groups of boobies are referred to as a "congress," a "hatch," or a "trap." I'm not sure what one would call the birders who went to see the Big Lake "congress" of boobies, perhaps a "congregation?"
Folks found out about the birds when fishermen took pictures of the odd birds that were hanging around small oil platform structures and shared them with Baton Rouge birder Eric Liffmann. It was Eric who alerted the birding community. The birds were located on structures about half a mile offshore. Several birders took boats to see the birds but others were able to see them well enough to identify them with spotting scopes.
The boobies seemed to favor one oil platform that had a silver Christmas Tree control structure on it. One would perch on a tall central pipe with the other two flanking it on lower pipes. So, the birders who viewed the boobies got to see most unusual Christmas ornaments about the time the box stores were putting out their Christmas decorations!
Brown Boobies stand out in a crowd of seabirds. They are about 2.5 feet long and have wing spans close to 5 feet. The flight silhouette is unique with long pointed wings and a pointed body fore and aft. Basic body color in adults and subadults is dark brown above. On the underside, the dark brown color extends onto the breast where sharp, contrasting white coloration extends to the vent and onto the wings. The bills and feet are bright yellow.
Juvenile Brown Boobies are dark brown all over. The feet are, however, yellowish.
All boobies and their cousins the gannets are plunge divers. They have heavy, wedge-shaped bills that facilitate entry into the water when they are plunging from well above the surface to catch fish and sometimes squid or shrimp. When prey is located, the birds pause and dive. Wings are first outspread, bent and finally folded back against their bodies as the birds enter the water.
Plunging permits the boobies to reach depths as great as 30 feet. Brown Boobies generally enter the water at a slight angle. Boobies can even use their wings to propel themselves once they have submerged.
Brown Boobies nest in the Tropics. They generally lay two eggs. The first bird to hatch invariably practices siblicide by destroying the un-hatched egg. So, why do the parents lay two eggs? In birds, the first egg laid is usually the first to hatch. But, if it doesn't hatch, laying two eggs means that there is a good chance that the second one will survive.
Jay V. Huner