Hello Frogs, Fish, Bats, & “Golondrinas” – Jack Ewing
Bye-Bye Mosquitos
Many years ago, before we had electricity, I had a small fish tank. I couldn’t use an air pump to oxygenate the water, so I had to struggle to keep everything in balance as best I could. Fish need oxygen, which is produced by green plants, which need nutrients, which are provided by fish feces, which comes from fish that eat everything from green plants and fish food to mosquito larvae. If you feed the fish too much, the excess food will lie on the bottom of the aquarium and decompose, a process which depletes the oxygen. You need just the right amount of each thing, fish, plants, and fish food. Snails are important too. They clean the algae off the glass. My fish were common guppies. A couple of tiny tree frogs also found the tank to their liking and added their presence to the mix. Plants, water, and mosquitos. What else could a frog want. This added a new twist to the balancing of the tank. Guppies like frog eggs and tadpoles, and tadpoles eat mosquito eggs, larva, and pupae. Is it any wonder that I failed to create a perfectly balanced aquarium and had to empty it out and start over a couple of times? It was quite a challenge which I never got exactly right, but I learned a lot about nature and especially about the dynamics of aquatic ecosystems.
That fish tank was the beginning of my understanding of mosquitos. After 53 years of living in the tropics, where mosquitos thrive, I’ve learned a lot. When Hacienda Barú was engaged in rice farming we had hordes of mosquitos. I remember one night when I had to wear a jacket, leather shoes and gloves, lather my face with repellent, and sleep under a mosquito net to keep from being ravaged. When we quit farming rice, and spraying insecticides all over the fields, the mosquitos diminished. In addition to the insects that damage rice, the insecticides kill a lot of other things, some of which prey on mosquitos, including dragonflies, spiders, frogs, geckos, and fish.
More information flows from trail cameras than I ever could have imagined back in 2011 when I started using them. Hiking or wandering through the rainforest is interesting whether or not you see any charismatic fauna of which there are 100s of species including anteaters, agoutis, all kinds of snakes, poison dart frogs, many different species of birds large and small, bright, and dull, and several species of carnivores. But how often do you see a jaguarundi, an ocelot, a tayra, or a puma? I recently retrieved and reviewed the memory card of a trail camera that was located at the edge of a swampy forest that bordered an open area. On the computer monitor I saw 11 different species of mammals, including three carnivores, six different birds, and one reptile. During the fifty years that I have lived near the rainforest I have seen all but one of the animals that were captured by the camera. But I had to walk 100s of hours to see some of them. Looking at the photos on that one camera taught me things and stimulated me to investigate things that otherwise would have taken me years to learn. Let me give you an example.
“I saw it too. It’s right there”, I pointed. Juan hastily dug a flashlight out of his backpack and shined it where I pointed. Right in the middle of the trail, coiled and posed to strike was a terciopelo viper (Bothrops asper). Normally we would have just gone around it and left it alone, but the trail was cut into the side of a hill with a steep upward slope to the left and an equally steep downward slope to the right. I found a long, forked stick and nudged it, assuming it would move out of the way. To our surprise, it attacked. While holding it off with the stick, we retreated backwards on the uneven trail with an occasional stumble. A fall would have been disastrous. It finally quit lunging at us, crawled off the trail, down the hill and let us pass. We both let out audible sighs of relief. It was a good sized terciopelo, about a meter and a half long and as big around as my wrist. Holding it away with a stick had been quite a tussle.
In the mid-1980s I had the opportunity to visit Caño Island in a small and none too speedy boat. The trip from Drake Bay to the island took more than an hour. Capitan Felix, owner of the boat, was a talkative soul, and fortunately his chatter was not the least bit boring. We learned the story of the island which had, at one time, been plagued with feral pigs. In 1976 when the government created Caño Island Biological Reserve the wildlife department decided it was important to rid the reserve of the feral pigs. Capitan Felix was part of a group of four local hunters who had been contracted to hunt the pigs down and kill them. They assumed that hunting feral swine would be like hunting peccary on the mainland, but then they found out that the wildlife department wouldn’t let them bring their dogs into the reserve. Their only alternative was to walk the length and breadth of the island repeatedly and shoot every feral hog they saw until none remained.
“It’s not the crabs that stink”, he laughed. “It’s the rotten coconut. They love it. When I need fish bait, I just look for a coconut husk that’s been cut open. If there’s still any rotting coconut meat left, it’s sure to be full of colonchos. See…” He stuck his hand through a hole in the coconut and pulled out one of the colonchos, which I later learned are called “hermit crabs” in English. Eduardo held tight to the shell, a little smaller than a ping pong ball, grabbed the crab’s head and pincher, and pulled steadily until the little invertebrate came free of its protective home, which Eduardo dropped on the ground. The head looked like a crab and the back part more like a fat worm. “Fish love them”, he said with a smile. Reaching into his bag, Eduardo pulled out a hand reel with some light fishing line and a small hook which he stuck through the crab and tossed it into the estuary. It didn’t take long before he had a nibble. After several tries, he hooked a fish he called a machaca. In half an hour he had four. They weren’t much bigger than his hand, but he took them home anyway. “My wife knows how to fry them up real tasty”.
Ethanol, with a few simple modifications to your engine, can be substituted for gasoline. It can be derived from many raw materials but is usually produced from corn or sugarcane. Since the carbon contained in corn and sugarcane is already here and available, ethanol doesn’t add any new carbon to the atmosphere. Plant fiber is made up primarily of carbon; so, to grow and produce biofuel these plants need to acquire carbon from their environment. A carbon dioxide molecule is composed of one carbon atom and two oxygen atoms (CO2). The green stuff in the leaves of growing plants is called chlorophyll. The plants get their carbon through a process called photosynthesis which involves sunlight, chlorophyll, and atmospheric CO2. In greatly simplified terms, the plant captures the carbon dioxide molecule from the air, keeps the carbon atom and uses it to build fiber for its own structure, and releases the two oxygen atoms into the atmosphere. When the corn or sugarcane plant is ready, we take it and turn it into ethanol. Cool, right? We get fuel for our cars and trucks and, at the same time enrich the earth’s atmosphere with oxygen. Well, not exactly. I must confess that I left out a few steps. Let’s have a look at how corn and sugarcane are grown.
I once accompanied him on a four-day adventure, during which I learned much of what I know about the Caribbean side of the country. It all began in a place called El Cairo in a restaurant owned by Juan Quiros Ching. No sooner had we finished our coffee and empanadas than the owner of the burro carro, our mode of travel for the first leg of the journey, walked in and shouted to Johnny that he was ready to go. The burro carro was a small platform with four railroad wheels. It was drawn by a mule. During the hour it took to reach the creek at the end of the spur, Johnny talked non-stop. “Years ago,” he began, “the immigration of Chinese to Costa Rica was prohibited by law. But what can I say; you know how it works. Laws are for common people like you and me, not for the wealthy, especially not back then. At the beginning of the century lots of Chinese were brought here to work as indentured servants in the households of well-to-do Costa Rican families. After a certain number of years of unpaid service, their debt was fulfilled, and their masters had to free them. Most took the last names of those same former masters and eventually acquired Costa Rican citizenship. Just like Juan Quiros”, Johnny continued. “He and his wife were betrothed as children and came to Costa Rica from China at the age of ten or eleven. To put it bluntly, their parents sold them to a rich Tico. They had to work for fifteen years to earn their freedom. Then they moved out here to the jungles of the Caribbean, along the railroad, and proceeded to make their fortune. They worked their butts off, but today they’ve got the business, a farm, and a pile of money”.
