Costa Rica Trip, 1998

Tom Davis

Last modified: May 12, 2000
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Here are some of our adventures on our fourth trip to Costa Rica. We spent a bit more than 2 weeks there.

Larger Versions of any of the images below can be obtained by clicking on them.

Other Costa Rica Pages

Photos of Costa Rican Animals
Butterflies of Costa Rica
Weird Moths of Costa Rica
Birds + Other Adventures (Lots of photos)
Travel Story—1997
Travel Story—1996

The Images

Zoo Ave Macaws

Macaws at Zoo Ave

Here are a pair of macaws at Zoo Ave, near San José. It's a zoo primarily for birds ("Ave" means "bird" in Spanish, not "avenue" as some people seem to think), The zoo is interesting because many of the animals are not in cages -- they simply wander around freely on the grounds. We visited the zoo on our last day in Costa Rica, and it was pretty easy to get shots like the one on the right.

We only spent a couple of weeks in Costa Rica on our fourth visit. We planned to do volunteer work at a biology field station in Wilson Garden near San Vito for most of it, to visit the OTS station at La Selva, and to spend a couple of days in the capital city of San José.

The previous year we had met a couple of students (Mauricio and Nicole) from the Universidad Nacional de Costa Rica who were extremely friendly and helpful to us during our visit to the Palo Verde OTS station. We remained in contact with them and invited them to join us for the La Selva trip this year.

Although they didn't know the La Selva area very well they know a lot about Costa Rican biology and natural history in general and are extremely good at spotting birds and animals. We went to La Selva at the beginning of our trip because Mauricio and Nicole's classes started during the second week of our vacation.

We flew to San José without incident (again carrying a huge load of medical supplies in addition to all our other junk) and arrived at our hotel relatively early. If you'd like to read about our initial experiences with bringing drugs into Central America, read the section entitled "Drug Running" near the top of that page.

Anne Ehrlich (the wife of Paul Ehrlich, with who we would be working during the last part of our trip) arrived the same day but on a different flight from a different city and she was staying at our hotel and planned to arrive at about 10 pm. We contacted Mauricio and Nicole who were too tired to meet us the first night, but with whom we made arrangements to have some adventures in San José the next day. We had a beer with Anne and then we all went to bed.

After breakfast, Nicole and Mauricio met us at the hotel, and we walked to the "Serpentarium" -- a small zoo for reptiles near the center of San José. Ellyn and I had both been there before, but never before with "snakeman" Mauricio. He's extremely interested in reptiles in general and snakes in particular, and it was fun to have a real expert explaining what we were seeing. We hung out there for a couple of hours, had some lunch, and then took a bus out the the suburb of San Pedro to the campus of the University of Costa Rica to visit an insect museum.

I'm not certain I could have found the museum myself -- it's in the basement of a building that's not part of any scientific department, but Mauricio knew where to go. The museum is quite small, but it's quite good. Almost all of the insects there are native to Costa Rica, although there were a few foreign ones, and there were a few exhibits of non-insect arthropods such as spiders, centipedes, et cetera. I had a great time, but I think Ellyn was a little sick of insects before it was over.

Afterwards, we went to dinner with Mauricio and Nicole and went to bed.

La Selva

The next morning we took a taxi to the bus station where we met Mauricio and Nicole again and boarded a bus for La Selva. It takes about 2 hours to ride from San José north through Braulio Carillo national park to La Selva, which sits on the northern boundary of the park. Mauricio's father works at La Selva, so Mauricio knows some of the employees there, and instead of having to lug all our stuff from the bus stop on the main highway into the station, Mauricio was able to flag down somebody he knew who gave us (and most important, all our junk) a lift to the headquarters.

There weren't many visitors, so we got two rooms next to each other, each large enough to hold 4 people. Each pair of rooms shares a shower, and all the meals are provided, as long as you show up on time. And since you're usually working (or in our case, playing) pretty hard during the days, the meals, although simple, always taste great.

Mauricio, Ellyn, Nicole, Tom

Mauricio, Ellyn, Nicole, Tom

Here we are (left to right: Mauricio, Ellyn, Nicole, and Tom, in front of the La Selva station. You can tell it's pretty hot, especially if you look at the larger version of this image, because the joint between Tom's shorts and zip-on pant legs is already soaked with sweat.

Most of the visitors to La Selva are biologists working on their research, but there are a few tourists like us. The situation was quite different at the Wilson Garden OTS station where we've had a lot more experience -- there, most of the visitors are tourists, and there are only a few researchers. And to preserve the "symmetry" of the situation, at Wilson Garden, we're more like researchers.

In any case, tourists who visit La Selva are entitled to one free "nature walk" with the resident naturalist, and there are walks scheduled twice per day. Since we were going to be there for two nights, we asked the receptionist if any of the walks would be better than others (less crowded, more interesting route, whatever). She said she'd avoid the one that afternoon since a large group of birders (bird watchers) was due, and as she said, "they're not interested in nature".

Obviously, waht she said isn't true of all birders, but she had a point -- the more aggressive bird watchers are often interested only in "checking off" birds from their list. Once they see a bird for an instant, they've "got" the bird, and have no interest in it any longer. If they were to see a jaguar in the forest, they probably wouldn't much care because it's not on their list. If they saw an endangered Harpy Eagle, they'd check it off with the same speed as they would a Clay-colored Robin, and move on to the next bird. We didn't particularly care what we saw; we just wanted to hike around and look at stuff, so we chose to go with the group the next morning, and went out on our own that afternoon.

We went on a lot of walks, both by ourselves and with the naturalist guide, and I'm a bit mixed up about what we saw on each walk, but we certainly saw a lot of interesting animals. We saw peccaries, tinimous, currasows, poison dart frogs, lizards, and hundreds of types of insects, but the "best" sighting for me was a sun bittern. We were sitting near the big river that separates the La Selva station itself from the primary forest in which most of the research occurs, and a strange, sort of nondescript bird was wading around. Despite the fact that we all had binoculars and a copy of the bird book, we couldn't figure it out. But the instant it took off, there was no question -- those fabulously patterned wings left no doubt.

Poison Dart Frog

Poison Dart Frog

Here's a poison dart frog that we found in the leaf litter at La Selva. They are quite tiny -- only a couple of centimeters long -- and they can usually be found in relatively dry leaf litter by the side of the trail. They're called poison dart frogs because the native indians use secretions from the backs of the frogs as a poison on the tips of their arrows or on the darts for their blowguns.

They're not terribly poisonous, as most of the guides didn't worry much about handling them with their bare hands, but on the other hand, there are many species, most of which are brilliantly aposematically colored, and some of them may be far more poisonous than others. I have only seen this particular species in Costa Rica.

Night Hikes

But the most "fun" we had were the "night hikes". As I said, Mauricio is especially interested in snakes, and the best way to find snakes is to go out at night with flashlights.

There are some big-time dangerous snakes at La Selva, the most dangerous being called the "fer-de-lance", or in Spanish, "terciopelo" (Bothrops atrox). There's also the "bushmaster" (Lachesis mutus), which is bigger and delivers more poison, but bushmasters are rare and not nearly so aggressive. The terciopelo isn't small (perhaps up to a couple of meters long), and they are aggressive. Earlier in the year a researcher had been badly bitten by a terciopelo and still hadn't recovered completely.

The La Selva station is designed to make life easy for the biologists -- although the rainforest, as you'd expect, is a sea of mud during the wet season (and sometimes not much better during the "dry" season), many of the main "trails" leading into it are actually concrete walkways. You can easily walk or bicycle deep into the forest, and then a half-dozen steps off the trail, you're in primary forest. So it's easy to have a false sense of security as you walk on the sidewalks -- it seems so civilized, but there's nothing to prevent a terciopelo from sunning himself right in the middle of the sidewalk. The woman who got nailed was apparently walking around at night in her sandals and was bitten on the foot.

In fact, it seemed like whenever anyone saw a terciopelo near the trail, they marked the general area with orange warning tape. I don't know what good it did -- I'm sure the snakes don't hang around for long -- and who knows how long the tape remains before anybody bothers to remove it.

On the night walks with Mauricio and Nicole, needless to say, it was always full boots and long pants stuffed into the socks. We never saw any terciopelos, but we did find 4 snakes, which Mauricio captured, identified, examined, and released. I personally kept my hands firmly in my pockets and let him do all the messing with the snakes. Some of the snakes we got were probably mildly poisonous; in fact, Mauricio got scratched by the fangs of one and he said that his thumb was a bit numb for a few minutes afterwards.

What I liked best about La Selva was that there were lots of interesting people around. At each meal you could sit at a new table and talk to somebody new about a different project. (Of course the fact that we only were there for about 6 meals made it pretty tough to run out, but there were a lot more people and projects than at the OTS station in Wilson Garden near San Vito.)

The End of Science

One of the more interesting conversations I had there was with a fellow who was studying leaf-mining beetles. The adult beetle lays an egg on a leaf, and after the larva hatches, it eats its way inside the leaf in a pattern that's pretty diagnostic for each species. As the path goes on, the larva, of course, is getting bigger, so the path gets wider and wider, and finally ends either where the larva is, or where it was when it emerged from the leaf.

I hadn't really noticed too many mined leaves, but after learning about them, I started noticing just how many of them there are. I was told that probably most of the paths I was looking at were made from moth larvae rather than beetles, but that nobody studies the moths.

The reason nobody studies the moths is what I found most interesting. Apparently a number of years ago a biologist came to Central America searching for leaf-mining moths, and collected lots of them -- perhaps 15 or 20 thousand different species, most of which were new to science. The guy was apparently interested in setting a record for the number of new species discovered by a single person.

With so many species, the collector didn't really have time to write up detailed descriptions of each -- usually he wrote just a couple of sentences about each. Furthermore, for the vast majority of the moths, he had only one or two examples of each species so he himself didn't really have a good idea of the variation that occurs within each species.

Finally, the whole collection was donated to the British Museum in London, and that marked the end of leaf-miner moth reasearch. The reason is that if anyone wants to do research, it's impossible to identify the species from just the one or two sentence descriptions that are available (and the "rules" of science state that the guy who discovers a species gets to name it, so to play by the rules, you've got to use the discoverer's names).

Normally, what you do in that case is to borrow a few specimens from the museum so that you can compare them with the sorts of creatures you're trying to identify. But the British Museum has the (very reasonable) policy that if there are only a tiny number of examples of a species in its collection, it will not loan them out -- you've got to go to London to examine the specimens. So anyone working on leaf-mining moths in central America would have to reguarly fly back and forth to London just to get the names of the creatures under study. And of course, nobody does -- it's easier just to work on something else.

Bullet Ants

Since we didn't see any really poisonous snakes, the most dangerous thing we saw was "bullet ants", or "ballas" in Spanish (Paraponera clavata), and we did see a lot of those. They look like pretty normal black ants, except that they are huge -- a couple of centimeters long. Your first thought on seeing one is that their name probably comes from the fact that they're the size of bullets. But apparently the name means that when they bite, it hurts like a bullet entering your body. And it hurts for a long time -- usually days. On a flight home from Costa Rica a couple of years before I sat next to a family who had just done 2 weeks there, and the little boy had gotten nailed by a bullet ant while walking around in his sandals. He said it was intensely painful for 2 full days.

I also read about bullet ants in the Costa Rican Natural History, edited by Daniel Janzen. (It's a fabulous book, by the way, but the section on bullet ants was particularly interesting.) The article was written by Janzen himself, and, among other things, described the excavation of a nest. Here's what he had to say:

On 6-8 August 1969 we excavated two nests of P. clavata at Finca La Selva, and we give the details here to obviate the need for further destructive sampling of the nests, which can be accomplished only the some human pain ...
It didn't sound like much fun to me.

They make nests consisting of a few hundred individuals in the bases of trees, and you'll often see them climbing on trees. We saw dozens and dozens of them, but we were careful and nobody got bitten.

One researcher at La Selva was actually studying them, and that sounded to me like a pretty heroic job. Since the nests are relatively small, the area around them isn't exactly swarming with bullet ants, but there are always a few, and I can't imagine how you'd avoid a bite or two if you spent all day messing with the nests.

All too soon the adventure at La Selva was over, and we took the bus back to San José.

Wilson Garden

We spent one night in San José and the next morning we rented a car for what's become an annual trip to the OTS station in Wilson Garden near the town of San Vito. Also, as we had done the previous year, we carried a huge load of pharmaceuticals with us to donate to the small "county" hospital in San Vito. It completely filled two big duffel bags.

This year the road was in pretty good shape (hurricanes the previous year had made the previous trip quite an adventure. There were still plenty of pot-holes, but fewer than there are in downtown San José. The Costa Ricans say that the pot-holes are so bad that only the drunks drive in a straight line.

When we go to Wilson Garden, we're never exactly sure what the project is going to be, and this year was no different. Usually we have a vague idea, but the researchers may have changed plans because what they thought they would do doesn't work out or they find something more interesting to study. This time we thought we'd be mostly working with butterflies again. Besides, the gardens are beautiful, and it's possible to see lots of stuff in your spare time.

Green Honeycreeper

Green Honeycreeper

Near the dining area at Wilson Gardens they often hung up a bunch of bananas which attracted a lot of birds -- tanagers, honeycreepers, and robins. Here's a Green Honeycreeper chowing down on rotting bananas.

But things were more complicated. In addition to the butterfly project, there were a couple of graduate students, Jennifer (Jen) and Taylor, who were working with birds and moths, respectively.

Jen's project involved doing bird surveys in various locations to see what was there. Some of the sites were in forest, some in coffee plantations, some in cattle pastures, and some in banana plantations. We'd spend a certain amount of time in each of these and record every bird we saw and what it was doing. Since it was our fourth year in Costa Rica, we were finally starting to know most of the common birds, so we only needed experts to consult on some of the tricky ones. The thing that made Jen's project ugly is that we wanted to be on-site by 6:00 am, so we were having breakfast at 4:30 am each day.

The bird action would usually drop off by 9:30 or 10:00, and we'd head back to the garden to take a nap and have lunch. After lunch, we'd help Paul and Gretchen with the butterfly project which often took much of the afternoon.

After dinner, Taylor's project started. The drill was to set up moth traps in various places which are basically buckets with a funnel leading into them and with a fluorescent light over them. The moths could enter easily, but they'd almost never find their way out. They didn't have all that long to find their way out, either -- there was a pest strip in the bucket that would kill them fairly quickly. We'd set up the traps at 9:00 pm, turn on the lights, guard the traps until 11:00, when we'd turn off the light and take the traps back. This isn't too bad, except that the bird survey started at 4:30 the next morning. Thank goodness Taylor only needed our help on alternating lights or the schedule would have killed us pretty quickly.

Except for the 4:30 breakfast, Jen's project was probably the most fun. We just spent hours looking for and at birds. Taylor's project was the most difficult because it was pretty boring. We'd take the traps out to a lonely pasture, set them up, and then wait for a couple of hours. Ellyn and I went together, and wandered up and down the roads, waiting for 11:00 to come around.

Taylor's moths weren't the only ones we saw -- there was a group at Wilson Garden studying long-horned beetles, and to catch them, they'd set up bright UV lights in front of white sheets or white walls at night. A few beetles were attracted, but for every beetle that came to the light, there must have been 100 moths.

Here's a whole page of moth photos that I took at the beetle traps over the period of a couple of nights. Taylor and Moths

Taylor with Moths

Taylor (in front) is examining some of the moths on a wall at Wilson Garden. For some reason, the diversity of moths that were attracted to these sheets seemed to be much greater than what we got in the traps in the fields. They were every color of the rainbow, and many of them didn't look anything like moths. Some were mimics of bees or wasps, some of flies, and many, many of them looked exactly like leaves. Many of the leaf mimics even had spots on the wings that looked like leaf damage caused by other insects or by mildew. I took my camera and flash to the walls, shot 4 or 5 rolls of film, and got hardly any duplicates. There were so many moths flying around that they were all over your clothes, in your hair, and occasionally, in your mouth. I thought butterflies were wildly diverse, but the moths just put them to shame. It's not too surprising, I guess -- there are about 10 times as many species of moths than of butterflies.

The Puppet Show from Hell

During the days, we helped Gretchen and Paul with the butterfly project which was similar to what we'd done the previous two years. Our work involved setting up a few traps, and visiting those that were set up to identify, mark, and release the captured butterflies, and to rebait the traps.

The one thing that was very different this year was that Paul and Gretchen thought it would be good to know if there was a big difference in the butterflies that are captured near the ground and those that would be captured up in the canopy. For the past 3 years, all of their traps where hung within a couple of meters of the ground. This was extremely convenient because you could just walk up to most of them and start working. But there's no reason to believe that the populations in the canopy are the same. The canopy can be 40, 50, or more meters up, the butterfly food up there may vary, there's more wind and sun, different predators, et cetera. It's also far more difficult to check the populations in the canopy.

Just getting the traps up into the canopy is a big deal. Climbing the trees is almost out of the question. The solution was to use a slingshot (or, more accurately, a "wrist-rocket" -- a slingshot that wraps back around the top of your wrist for added stability). The whole thing is powered by surgical tubing, and it can really launch its load a long way.

What we did is to attach a couple of lead fishing weights to the end of a monofilament fishing line and shoot the weights with the slingshot. The other end of the line was hooked to a standard spinning reel and the first section of a fishing rod. Gretchen and Paul had done some research and found that two sinkers provided the right amount of weight -- more and the energy of the surgical tubing wasn't enough to get it high enough, and less didn't go as high either as the weight and drag of the line overwhelmed the momentum of the flying sinkers. Slingshot

Hanging a butterfly trap

To hang a trap in the canopy, we'd first fire a lead weight tied to a fishing line over a branch with a slingshot. Here I am with the slingshot, Paul is behind me with the fishing rod, and Gretchen is trying to figure out where the weight will go. I've got the slingshot stretched so far that I really have no idea where I'm aiming.

We'd find a suitable branch and try to launch the weights and line over it. This usually took a lot of tries, and we left a lot of sinkers hanging in the canopy. Not only did you have to get the weights over the branch, but you had to coax them down the other side -- typically, even if you got the line over a branch, the friction of the junk on the branch caused the line to stop with the weights only a meter or two down the other side. So you would keep flicking the line you held, and watch the weight slowly ease its way down the other side (or not -- sometimes it would just get stuck, and you'd have to try again).

The process was complicated because it seemed that you never got a straight shot at the branch -- there's all sorts of other crud growing around, and you were never on the level when you were taking a shot. Although it's difficult to see in the photo above, we were standing on an extremely steep slope. It's also a little dangerous -- since the slingshot is pulled so far, you can't really see where you're aiming, and if the weight hits something near the ground, it ricochets at an unpredictable angle and amazing speed. For that reason, everybody turned their head away just before the shot was fired. Not surprisingly, I guess, the most commonly hit obstacle was the "Y" of the slingshot!

Anyway, when you finally got the line over a branch, we would then tie a stronger cord to the monofilament and pull that back over the branch. Then we'd tie the trap to the heavier cord and pull it up into the canopy.

The other major problem with working in the canopy is that when you catch some butterflies, it takes a long time to get the traps back down to the ground. As you're lowering it, the trap is shaken pretty thoroughly, and this often allows the butterflies to escape. For the traps at eye level, it's easy. The first thing you do when you walk up to a trap is to close the entry hole so the butterflies can't escape. Since the traps are just long cylinders of mesh (here's a picture of one), you grab the mesh in your hand to close the trap.

To solve this problem, a sort of "skirt" was added to the bottom of each trap that was held up with tiny velcro attachments, but could be closed by a tug on a second line connected to the bottom of the trap. We just made the whole line into a loop, so the top of the trap had a line hooked to it that passed over a branch, down to the ground, and then looped back up to the bottom of the trap, where it served as a trigger to close the trap. You just had to be careful while you were lifting the trap to make sure that you didn't accidentally tug on the lower line.

One day Gretchen and I were out servicing our trap lines and we came upon quite a scene. The trap was hanging in the canopy, but it was surrounded by a troupe of howler monkeys who seemed extremely interested in it. And for good reason, too; the traps are baited with a combination of bananas on the verge of rotting, molasses, and rum, and it probably smelled pretty good to the monkeys. I guess in their attempts to get at the bait, they'd managed to tangle the lower cord in some branches in the canopy, so when Gretchen and I tried to lower it, the whole trap wound up hanging upside-down from the skirt-release cord. We tried tugging on both of the cords repeatedly, with no effect, except possibly to cause the tangle to get worse. The monkeys were, of course, fascinated, and as we jerked on one cord after the other, the whole trap jumped around like an insane marionette. We were getting more and more frustrated and seemed to be making less and less progress when Gretchen finally declared the whole thing to be "the puppet show from hell". We wound up laughing so hard at this that it probably took 5 minutes before we could do anything useful. We never did get that trap down, and a couple of days later a new one was hung nearby.

More Terceopelos

We delivered the medical supplies to the emergency room doc at the hospital in San Vito whose name is Pablo Ortiz. To thank us he invited us over to his house one afternoon for cake and coffee, and he was loaded with interesting stories about practicing medicine in Costa Rica.

The most interesting to me again involved a terceopelo, or rather, many of them. The people most in danger of getting bitten are farmers because they tend to work with their unprotected hands in the undergrowth. Apparently one unlucky soul was scooping up a load of wood and stuck his hands into a nest of the vipers. It was impossible to count the number of bites he got because things were so badly swollen by the time he got to the hospital, and Pablo was sure he was a dead man. I guess he normally gives one or two "units" of the antivenin for a typical bite, so he just gave the farmer 25 units and put him on a flight to the hospital in San José.

The next day there was a phone call from the hospital, and Pablo figured it was just somebody telling him the patient had died, but no. It was the patient himself, completely upset that his false teeth had been lost somewhere between the viper nest and the San José hospital!

Pablo's other stories weren't so upbeat. A few years ago he said that the most severe injuries he typically treated were wounds from machete fights. But now, with the ever-increasing demand for drugs in the United States, more and more of them are being trafficked through Costa Rica, and he's seeing more and more gunshot wounds. Ten years ago he never saw any and now they are relatively common. So even though Costa Rica is neither a producer nor a consumer of cocaine, it's been dragged into Reagan/Bush/Clinton's glorious "war on drugs".

Finally, Pablo had some interesting observations on the way death is treated in the United States and in Costa Rica. He did his residency at Massachusetts General Hospital (or "MGH" -- "Man's Greatest Hospital", according to those who work there), so he knows a bit about attitudes in the US.

He said that when he has to tell an American that he's going to die, it's almost as if the patient can't believe that death can occur. In the United States, dying people are spirited away to hospitals, and quite often none of their relatives see them die. The kids never see it, and are told that "granda's sleeping" or something similar.

In Costa Rica, when grandpa dies, the kids are usually there, holding his hand, and the parents make it clear that he's not coming back, that death is a normal part of life, and that it will happen not only to grandpa, but to the parents, and to the kids eventually.

El Niño

This was the year of El Niño, and although most folks think of it in terms of excess rain (California and Ecuador, for example, got about twice as much rain as normal), that excess rain had to come from somewhere, and Costa Rica was one of those. It was surprising to walk in the rainforests through dry leaves. Normally there's a mass of rotting leaf litter on the ground. It was dry both at La Selva and at Wilson Garden. We were all hoping that there would be no fires -- this is the first time I've seen conditions where something would actually burn, and there's a lot of fuel in the rainforest.

One day after we'd set a bunch of butterfly traps and were racing back through the leaf litter so that we wouldn't miss dinner I got the scare of my life. The day before we'd been talking to Pablo about terceopelos so that story was fresh in my mind when 3 feet in front of me a very hefty snake suddenly rose up out of the leaves. We didn't get a positive i.d. on it, but it certainly wasn't a terceopelo. But that sure didn't stop my heart from cranking along at about 180 beats per minute for some time afterwards.

After our stay at Wilson Garden, we returned to San José, spent a day visiting the zoo just outside of town, and going to dinner with my Spanish teachers. Unfortunately, the dinner was at a restaurant where the music was pretty loud, so it was hard to understand anything and we did most of our talking in the car going to and from the restaurant. The next day we returned to San Francisco.

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