Originally published in The Manitoban, 2011
This week I have been bitten by fire ants, termites and a cactus. Now I've got all that out of the way, I hope to spend the rest of my stay in glorious Puerto Rico in perfect harmony with nature. I would especially like to harmonize with the common coqui frog, Eleutherodactylus coqui. They have a very pretty song.
While I have not yet seen one, they are the first thing I heard when I set foot on this fascinating island. Male coquis start singing as soon as the sun begins to set, currently around 6pm, and they continue singing until the sun comes up around 6:30am. Males sing to advertise to females and announce their territory to other males.
Named onomatopoeically for their song (ko-kee, ko-kee), the coqui belongs to the genus Eleutherodactylus, a long Greek name lending itself to over 600 species, meaning “free toes”. This refers to the fact that members of this genus do not have webbed feet, but have individual and unattached toes with large pads adapted for climbing. As you might guess, coqui frogs are arboreal, climbing trees as the sun sets to hunt insects until dawn, at which time they retreat to their hide-outs for the day. Just like teenagers and goths.
Coqui frogs are very small, ranging from 15 to 80mm in length. In fact, coqui means “little frog”. Unlike most frogs, fertilization is internal and coquis do not lay their eggs in water but terrestrially in moist areas. The young develop within the egg over a period of about 17 to 26 days and hatch as miniature adults with very small tails that disappear shortly after hatching. The tadpole stage occurs within the egg so there is no free-living larval stage as in most frogs. There are also developmental differences; some of the stages that free-living tadpoles pass through are absent in the coquis.
Coquis reproduce year-round but the majority of breeding takes place during the rainy season from about September to December. Male coquis guard the eggs and remain at the nest for the first few days after their eggs hatch, but by that time, the females are long gone. Females usually lay between four and six clutches of anywhere from 16 to 41 eggs per clutch – with a schedule like that, it's no wonder she doesn't stick around!
For the taxonomically inclined, coquis belong to the order Anura and family Leptodactylidae. In Puerto Rico there are 17 species of coqui frog; however, only two of them actually have the 'ko-kee' song for which they are named. Three species of coqui, web-footed, mottled and golden, are believed to be extinct. The golden coqui, E. jasperi, is (was?) the only member of the family Leptodactylidae that gives birth to live young.
Common coquis are found on St. Croix, St. John and St. Thomas, U.S. Virgin Islands, Dominican Republic, Vieques, and Florida. They are considered an invasive species in Hawaii, where efforts to eradicate the little guys are under way. The common coqui is doing quite well on the island of Puerto Rico, and Puerto Ricans like it that way – the coqui symbol is used by many local businesses and institutions and is advertised as a source of local pride.
In fact, in my tireless efforts to bring you only the most well-informed articles, I drove all the way to Rincon to check out an Oktoberfest (yeah, I know, right?) celebration sponsored by one of Puerto Rico's two local breweries, Old Harbor Brewery based in San Juan, so that I could sample their Coqui Lager. Coquis are great, but I liked the pale ale better. At that point, I didn't know what animal that ale was named after, but there is a Puerto Rican boa that's endangered, so stay tuned next week for the low down on that lovely creature.