Karen London reports on the charm of the tiny Puerto Rican frog, which has become synonymous with nationhood.
The sound of the calling frogs in the rain forest at night is magnificent. In the early hours of our last morning on a recent vacation in Puerto Rico, I listened with great attention to the calling of the coqui frogs, knowing that when the sun came up, I would have to say good-bye to this glorious chatter. The calling commences when the sun sets, and it continues throughout the night until first light.
The coqui is such a powerful symbol of identity in this beautiful commonwealth of the United States that it has given rise to the expression “más puertorriqueño que el coquí,” which means “more Puerto Rican than the coqui.”
Sixteen different coqui species live on the island, with 13 occurring in the Caribbean National Forest, which is a treasured 28,000-acre area of rain forest. The best known and most abundant species is the Common Coqui, Eleutherodactylus coqui. Since these frogs are small, anywhere from 1.5 to 8 cm long, it has been said that the frog’s name is longer than its body.
The genus contains over 600 species, which some claim make it the vertebrate genus with the most species. Eleutherodactylus means “free toes” and refers to the fact that these frogs, unlike most frogs, do not have a membrane between their toes. Their toes have little pads on the tips of their toes, which allow them to hold onto leaves, walls and other surfaces, but the lack of an interdigital membrane suggests that they are not adapted for swimming.
Coqui frogs are unusual in the world of amphibians in that they lack a free-living larval stage. That is to say, coqui frogs pass through their tadpole stage while still in the egg and when they emerge from the egg, they are fully formed and functional froglets, though very small. The males guard the eggs to prevent them from drying out and remain in the nest for several days after the new froglets appear. Females lay clutches of about 25 to 30 eggs and they do so roughly five times per year. Breeding occurs throughout the year in Puerto Rico, though the wet season is a particularly active time for coqui reproduction.
The frog’s name is onomatopoeic for its “Ko-kee!” call, which is an advertisement call used by males during the mating season to attract females with which to mate. Only male coqui frogs call. The call is actually made up of two distinct parts — the “Ko” and the “kee” components of the call have very different purposes and are intended for different listeners. The “Ko” is a call to other males to tell them to stay away — sort of a “Back off mister, this spot is taken” kind of a call. The “kee” attracts females, so I would translate it loosely to mean, “Hey baby baby.”
I like the call of the coqui enough that I was not surprised to learn that it has been made into a ringtone, though I doubt I find the call as pleasing as the average female of the species finds the real thing.
Karen B. London, Ph.D., is a certified applied animal behaviorist, certified pet dog trainer, author and an adjunct faculty in NAU’s Department of Biological Sciences.
For the original report go to http://www.azdailysun.com/lifestyles/columnists/article_e79237ef-f79e-5823-b7d3-84858908d12c.html
Photo from http://www.wildhorizons.com/