Sadly, snakes are inactive this time of year in northern Utah. With lower-than-average temperatures dipping below 0° F every night, I've had a lot of time indoors to read and daydream about snakier times and places. You can imagine my envy of my colleagues Susannah French, Nick Kiriazis, and Lori Neuman-Lee, who are currently in the Galápagos Islands studying Marine Iguanas. Nick, a student teacher at South Cache Middle School in Hyrum, Utah, is blogging about their research experiences at his blog, The Learning Scientist, which you should check out. Before they left, I instructed them that they were not to pass up an opportunity to observe the endemic racers of the Galápagos, the only snakes to inhabit the famous archipelago (other than one sea snake species, found offshore).
|Galapagos Snake from Bartholome Island|
|Galapagos Snake eating a lava lizard (Microlophus sp.)|
|Plate from Steindachner 1876|
|Galápagos racers mating|
|A Galápagos Snake among some Marine Iguanas|
|Galápagos snake eating a small iguana|
I was surprised to find how poorly known these snakes were given the infamy of the islands they inhabit. Because they are probably important predators on Galápagos finches, mockingbirds, and small lizards, as well as on non-native rodents, they deserve more study (although as Nick has pointed out, permission to study animals in the Galápagos can be difficult to obtain). Along with many of the Galápagos' other reptiles and birds, the snakes were probably almost driven to extinction by introduced cats and rats, against which they had not evolved defensive behaviors. Their natural predators probably include Galápagos mockingbirds. Today, tourism and development, although limited in the Galápagos, probably threatens these snakes as much as invasive species, which are beginning to be brought under control. Nick, Lori, and Susannah are busy studying the effects of tourism on the Marine Iguanas - who is studying the Galápagos snakes?
Special thanks to Nick Kiriazis for inspiring me to write this article with his blog, and thanks to Lori Neuman-Lee, Manuel Mejia, Dave Irving, Jim Moulton, Rosalind Gomes, and Phillip Marsh for their pictures.
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