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mona_islandThe weather in New York has turned distinctively wintery, so Ferrebeekeeper is going to compensate by featuring a little known tropical island! Isla de la Mona (“Island of the Bow?” Mona Island?” help me out here, Spanish speakers) is a small island which lies in the strait between Puerto Rico and the Dominican Republic. The island measures 11 km by 7 km (7 miles by 4 miles) about the same size as Manhattan. But while 1.7 million people live on Manhattan, Isla de Mona has only a ranger station and no true permanent residents.

Indeed, Isla de la Mona is something of an anomaly in the world: becoming less inhabited over time. In ancient times the Arawak Indians dwelled there. Archaeological evidence establishes their presence on the island by at least 3000 BC. However after Columbus (who officially “discovered” the island), the murky affairs of the colonial era caused the island to gradually depopulate. At one point, the island was controlled by Francisco de Barrionuevo, a Spanish grandee who fell afoul of Alonso Manso, the rapacious bishop of Puerto Rico. Bishop Manso was fond of proscribing wealthy enemies and seizing their possessions and retainers. To escape this fate, de Barrionuevo escaped to mainland South America, and he took most of the island’s remaining inhabitants with him. Thereafter, remaining natives were generally impressed (enslaved?) by French corsairs. The emptied island became a haunt of pirates including the infamous Captain Kidd. It passed to American control in the Spanish American War and remains an administrative part of Puerto Rico (although it is actually closer to the Dominican Republic).


Abandoned lighthouse in the middle of a cactus forest on Mona Island

In the modern era, Mona Island, was mined for guano. During World War II, it was attacked by a German u-boat in what must have been a thrilling “Hellboy” or “Indiana Jones” type adventure (or maybe the submarine was trying to disrupt the Allies’ nitrogen supply). Today the island is entirely a nature preserve, and no more than 100 people can be on it at a given time.

Because of this enforced isolation, the island has a pristine ecosystem of dry scrublands and tropical forests. There are extensive sea-caves and coral reefs around the island. As you can imagine, it is a refuge to wildlife such as sea turtles (which are displaced by beach development everywhere else). Unfortunately feral pigs, goats, and cats have invaded the island and messed up the unspoiled ecosystem, but they are kept somewhat in check by annual hunts and by the efforts of the Park Service. I think it is thrilling to imagine this empty island out there. It pleases me no end that there are still such places.


Nepenthes rafflesiana elongata (upper pitcher)

Nepenthes rafflesiana elongata (upper pitcher)

Yesterday’s post described the carnivorous nepenthes plants which entice organisms into their slippery liquid-filled depths where the tiny creatures are killed and digested.  The plants however are after different nutrients than carnivorous animals are.  Instead of hungering for proteins, carbohydrates, minerals, and complex amino acids (and all that other stuff nutritionists and zookeepers are always going on about) plants simply want phosphorus and nitrogen.

The small wooly bat (Kerivoula intermedia)

The small wooly bat (Kerivoula intermedia)

The small wooly bat (Kerivoula intermedia) is a tiny vesper bat which lives in Malaysia (the portion on Borneo). The small wooly bat weighs between 2.5 to 4 g (0.08 to 0.14 ounces) and, at most, measures 40 mm (1.6 in) from nose to tail.  It is one of the smallest mammals alive—it is even smaller than the miniscule lesser bamboo bat (which lives inside of single segment chambers in bamboo stalks).  The small wooly bat has found an equally fine home: the tiny creatures live inside a Bornean subspecies of nepenthes– Nepenthes rafflesiana elongata.  The little bats fit perfectly inside the long tapered chambers of Nepenthes rafflesiana elongata—the taper even prevents the tiny aerial hunters from falling in.  In exchange for providing a perfect home for the tiny bats, the plants also get something.  Bat guano is a famous source of nitrogen and phosphorus—so much so that humans have been known to mine old bat caves to use the deep layers of excrement for an agricultural fertilizer.


Nepenthes rafflesiana elongate does not need to be an effective hunter.  The bats which live inside its tube shaped pitchers provide it with the nutrients it needs on a continuing basis: the two organisms provide a beautiful example of a symbiotic relationship.

woolly bat with pitcher plant

Ye Olde Ferrebeekeeper Archives

June 2023