Thursday, August 23, 2007

Blue Footed Boobies

While I have a real affinity for the land iguanas, and the penguins are cute, these birds are just so much fun to watch I have decided they are my favorite Galapagos animal. It’s an amazing site to see 200 or more of these birds dive in unison into very shallow water from as high as 45 feet in the air, then quickly pop up to the surface as if their bodies are made of cork. The blue footed booby can dive into water as shallow as one half a meter.

The air sacs in the skull of boobies in general help to cushion the impact of these high speed controlled crashes into the water. They can also close their nostrils to keep out the sea water.

Like many birds, the females are larger than the males, and the pupils in the eyes of the females are larger than those of the males as well. Our guide Javier, told us many eventually go blind as they age due to damage to the eyes from the impact into the water.

The name booby is derived from the Spanish word “bobo” which means fool or clown. During courtship they do appear clownish as they walk around raising one, then the other blue foot in the air.

Blue footed boobies breed when resources are available. The female lays up to four eggs, about 3-5 days apart. This is not an uncommon strategy among birds. If food resources are limited usually the oldest chick will survive, if there is plenty of food the younger ones may as well. They eggs are incubated on the feet of the adults, and a guano nest is made when hatching occurs after about 40 days of incubation.
One of the instructors of the class (a herpetologist by the way) and I had an ongoing discussion about birds being just a branch of the reptiles. While I understand the relationship between birds and reptiles, I maintained birds are deserving of their own class since they are different from reptiles in important anatomical and physiological ways. However, that chick looks a bit reptilian even to me.

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