Wednesday, February 24, 2010

The Long Walk Awaits

Our time at La Selva has passed quickly. Perhaps it was the four straight days of pouring rain (in the dry season, no less) that makes me feel as though I haven't spent enough time in the forest. Or perhaps it was the valiant battle I waged against something inside of me (a virus? maybe a parasite?) that makes me long for more free hours to explore the surrounding jungle.

In any case, we set off tomorrow. By Friday morning we will reach the entrance to Corcovado National Park. This is no-easy access facility though, once we arrive we'll have to hike 17 km (10.5 miles) to the remote field station that will be our home for six nights. We were told to expect the trek to take about five hours, but I will surely take more time, so I can photograph any wildlife we come across.

Located on the Osa Peninsula on Costa Rica's Pacific Coast, Corcovado is one of the wildest places left in Central America. All five species of big cats roam through the park (last week a puma was spotted right outside the field station), tapirs are a common sight, and rare scarlet macaws and harpy eagles may be spotted flying overhead. It's the site I've been looking forward to most. It will be much different there than here in La Selva, a high-tech research facility. Corcovado doesn't even have a phone.

With our impending departure on my mind, I took off this morning to take a few moments to explore the La Selva jungle. It wasn't long before the research buildings were far behind me (in sight and in mind) and I felt enveloped by the tropical forest. Walking softly, I was soon in the midst of a herd of foraging peccaries. Startled by my sudden presence, one of the larger animals became alarmed and snapped its jaws nervously. As the peccaries grunted aggressively, I realized I may have gotten too close and slowly backed away from the herd.

Peccaries are common around La Selva, even in the mowed yards around the research buildings. They're so common and unfazed by our presence that it's easy to dismiss them as being as harmless as the dogs and cats in your neighborhood. But I was in their neighborhood now, and they were quick to remind me why they're formidable foes for potential predators like jaguars. Although the peccaries may be relatively accustomed to humans in this forest, they're ready for anything and won't be caught unawares by any potential dangers. It was a good lesson to learn before our arrival in Corcovado, home to crocodiles, jaguars, puma, and thousands of venomous snakes. I'll be sure not to be too complacent.

Iguana Go Swimming

If you spend much time on the suspension bridge over the Río Puerto Viejo, you’ll eventually notice some large green forms in the uppermost reaches of the trees on the river banks.



They’re green iguanas (there are five in the picture above), and the largest individuals are dominant males surveying their territory. If you look even closer, you’ll see a number of females in the trees as well; they’re smaller and don’t have the bulk or the orange tint of the mature males. The males will typically have a few females in their harem, and they’ll undertake vigorous territorial displays if they feel another male is getting too close. Mostly though, they spend their time lounging about and perhaps chewing on some leaves.

Most are familiar with the small, bright green juvenile iguanas you see in pet stores, rather than the large, territorial beast, but make no mistake they are the same animal. Iguanas make suitable pets for only the most dedicated pet-owner, they can get massive, with a potentially dangerous bite and whip-like tail. They are a formidable adversary for any potential predator. Next time you’re considering a new potential pet, consider these iguanas, lazily lounging about 200 feet up in the forest canopy and think hard about whether you can replicate their needs in your home.

Iguanas are high-divers too. When threatened, they will jump out of their tree and into the surrounding water, probably crashing through a ton of branches in the process. This strategy will surely dissuade any hungry cat from coming after the iguana, but it just might make a hungry caiman’s day.

Tuesday, February 23, 2010

Welcome to the Jungle

La Selva Biological Field Station is the crown jewel of the Organization for Tropical Studies system. Established in 1954 as an experimental station to research natural resources, it was purchased by OTS in 1968. Since then, thousands of researchers have worked here to unravel the mysteries of the tropical rain forest. This is not small potatoes; an incredible 240 scientific articles are published each year based on research conducted at this site. As you can imagine, there is a steady stream of students, professors, and biologists coming through the area at any given time.

Our travel to La Selva was delayed three hours as our bus waited in traffic and we were well behind schedule by the time we finally arrived. I craned my head out of the window as we rolled onto the property to watch a herd of collared peccaries grazing nonchalantly in the fading light, wholly unconcerned by our sudden presence.

After we unloaded, I took advantage of the few minutes remaining until dinner to stroll around and soon came across the famed suspension bridge over the Río Puerto Viejo. The bridge separates the dorms, administration building and cafeteria from the forest, and as it creaks back and forth, one is afforded a great opportunity to see wildlife in the tree canopy, which is now at eye level.

There was chattering in the trees as unknown birds, perhaps toucans, bickered with one another and a soulful hooting as Great Tinamous, bulky ground birds, called to each other in the coming darkness. Howler monkeys hooted in the distance, letting other troops know the limits of their territory. The forest was alive with animals. Much of La Selva is primary rainforest, meaning the trees have never been harvested. This also means that much of the native wildlife is here as well.

There was little time to go searching for them though, as we soon departed on a night hike after dinner. Several frogs were seen, including the charismatic Red-eyed Tree Frog, but as the hike wore on more and more people dropped out to return to the dorms. By the time we returned, we had been hiking in the dark for three and a half hours. It was a hike to set the tone for the next day.

After breakfast we undertook another hike, to learn of the forest and become oriented to some of the common species and processes occurring in this area. The climate at La Selva is much different than at Cerro, this is the jungle you think of when someone says “tropical rain forest” and the muggy heat made it difficult to stay hydrated.

Lunch provided a brief respite from more hiking, which took place in the afternoon. After dinner, we briefly discussed the project we’d be researching the next few days, an attempt to characterize amphibian populations in several wetlands. Of course, to reach these wetlands required more hiking, which we started as soon as we ended our discussion. In the darkness, we stumbled through the forest and conducted searches for amphibians and reptiles once we were inside one of our study swamps. Many frogs were grabbed, as well as a Lichen-colored Slugeater ( a small, semi-arboreal snake, you can probably guess what they feast on).

Our second wetland proved to be a physical challenge and we struggled mightily to free ourselves from its deep mud, hungry for our rubber boots. It was difficult to focus on finding and catching frogs when unable to take a step without a valiant effort to free ourselves. The swamp drained the energy from our already tired legs. I figure we had spent about twelve of our first 30 hours at La Selva hiking, and I was drained. By the time I finally got back to my room, I could barely bring myself to remove some of the mud off my body with a paper towel before I fell into bed, unconscious before my head hit the pillow.

Saturday, February 20, 2010

Valley of the Quetzals

Perhaps one of the most famous residents of the Central America highlands is the Resplendent Quetzal, it’s certainly at least the most well-known among the bird watching community. The species is a member of the Trogon family; and although this group of birds is particularly colorful, the quetzal stands alone. With a long and extravagant tail about three times the length of its body and feathers so bright blue the entire bird looks like a neon sign, the quetzal looks like a character out of a fairy tale.

I was informed quetzals were occasionally spotted in Cerro de la Muerte before we arrived and the thought of finding this exceptional bird during my stay soon began to fester in the back of my brain. Egged on by the pleas of State-bound bird aficionados that I “had” to see a quetzal during my time in Costa Rica if I ever found myself within 200 miles of one, my quest became an obligation to avoid a guilt trip upon my return. Being able to boast of seeing a quetzal would be much more satisfying than the disapproving head-shaking and hypothetical tales of the great lengths others would’ve gone to and tribulations persevered through just for a brief glimpse, should they have been in my shoes. A realist by nature though, especially when it comes to the chance of observing rare wildlife, I was not particularly optimistic regarding my chances. However, the revelation that we’d be staying at the Quetzal Education Research Center* was an encouraging sign.

I’ve decided to make this blog as anti-climactic as my quest to find a quetzal. I saw one about five minutes after I walked out of the research station the morning after arriving, while I was standing in the yard.

Perched in plain view, I frantically fumbled with the straps of my camera bag and rushed to take a picture before this holy grail of birding flew away. My frenzied attempt at a photograph isn't worth posting here, despite the bird's close proximity.

With this monkey (bird) off my back in short order, I was free to take a more relaxed approach during the rest of my stay at Cerro de la Muerte. Compared to Palo Verde, the forests of Cerro were lush, verdant, and I could feel the moisture in my lungs (instead of dust) when I breathed.

The high elevation oak forests appeared full of life as exotic birds flitted through the dense underbrush, weaved in and out of the moss laded branches, and soared high above. There were species familiar to most amateur east coast U.S. bird watchers, like Swallow-tailed Kites and various warblers; they were spending their winter in the warm tropics. There were also a wide variety of species not found outside the tropics, like the Emerald Toucanet and Blue-gray Tanager. But, perhaps the greatest diversity I observed was among the myriad of tourists who fly in from across the globe to check birds off their life lists, they hauled their giant lenses and spotting scopes to and from their cabins and lodges, nestled into the mountainside.

Yet, despite the vast distance many of them had traveled to arrive in Cerro, one didn’t have to travel deep into the forest to leave all sign of them behind. It was there that my group spotted a mated pair of quetzals perched above a small stream.

Located along the Talamanca Mountain Range, we were within a portion of a vast protected area that connected national parks, providing a vital conservation corridor. One of the unique features of the area is the paramo, a high elevation habitat above the tree line. Only grassy and shrubby vegetation can be found here, and they’re well-suited to the huge fluctuations in temperature that are typical of these high elevation sites. My group visited a paramo in the afternoon, and although we were warned by the morning group to bring lots of suntan lotion, by the time we had arrived the fog had rolled in and had made a sunburn about as likely as getting a good slice of pizza before I get back to the U.S.

The fog advances

Kim is blissfully unaware of the deathly fog approaching her

*So far, the showers at the stations we've stayed in have had two temperatures, "cold" and "is this colder than it was last time?" but the Quetzal Education Research Center was a notable exception. The temperature went from literally scalding to ice cold (and back again) almost as fast as the water shut on and off. It was perhaps one of the most unpredictable experiences of my life.

Wednesday, February 17, 2010

Living on the Edge: Insect Repellent

Most everyone knows habitat loss is one of the major reasons we are losing biodiversity across the globe. Many species have particular habitat requirements, like the gopher frog, which breed in seasonal wetlands within longleaf pine forests, or red-cockaded woodpeckers, which nest in forests containing mature pine trees. When these habitats are gone, the animals can’t persist. That much is fairly straightforward.

But, when half of a forest is destroyed, is the remaining forest as good as ever (albeit a bit smaller)? The answer is no, and it’s due to what ecologists refer to as edge effects. When the border of a habitat is altered, the interior may be affected in many different ways. These edge effects need not be generated from complete conversion to other land uses; a road, a powerline corridor, or even a footpath can influence surrounding habitats. For example, when a road is constructed through a forest, the temperature of the woods increases because there is less canopy cover to block the sunlight. This may also result in a decrease in humidity levels and more wind, again because there are less trees to serve as a buffer. In the northeastern United States, roads are salted frequently after winter storms to melt the snow and ice; these salts are known to seep into surrounding wetlands and influence tadpole development.

Those are all examples of what we’d call direct effects of edges, but there are also more subtle consequences. For example, edges may serve as a barrier to dispersal for many species. Some species, like insects or other invertebrates, may be unable to cross an open area because they dry out or get eaten. Larger but slow moving animals, like turtles, may be run over by cars on roads that cut through their habitat. This functions to isolate groups of animals, which is dangerous for two reasons. Smaller populations are more likely to go extinct simply because of chance events (like a disease outbreak, for example) and smaller populations have reduced genetic diversity, which is never a good thing.

During our stops through Costa Rica, we break up into small groups and conduct short-term research projects to investigate the biology and ecology of tropical systems. While staying in Cerro de le Muerte, my group undertook a small study to determine how a lightly used and unpaved road might influence assemblages of invertebrates. To explore the issue, we placed a one meter square (made with PVC pipe) over the ground at two, 10, and 40 meters (6.5, 33, and 131 feet) from the road (repeated four times for a total of 12 squares. Within these squares, we collected all the leaf litter and small sticks and tied it all up within a garbage bag for storage.

The Study Site

Back at the lab, we sifted the leaf litter through a sieve and collected all the spiders, cockroaches, beetles and everything else alive that fell through. By the time we had sorted through all of the leaf litter, we had collected nearly 800 individual critters. Not bad for just 12 small squares. Although the few large animals that we see get most of our attention most often, if nothing else we should all be aware of the millions of invertebrates that are underfoot all the time, providing an important link in the food webs of every habitat on earth.

We weren’t really sure what to expect from our results. One might think that when a habitat is degraded, such as after road construction, the diversity and abundance of organisms would decrease. That’s the most straightforward expectation. But, when a habitat is altered, a new habitat is created, and this new habitat may suitable for new species that invade the area. If the original species still hung around, then you would actually expect a greater diversity of organisms after the disturbance than were present before.

We documented the first scenario, a clear trend indicating the diversity of invertebrate animals increased sharply as we sampled further away from the road and into the forest interior. This was relatively surprising, as the road we sampled was small, unpaved, and traveled by only a few cars each day. If the number of small, ecologically important animals is affected so drastically from just a glorified footpath, one must wonder at the magnitude of how we our actions are affecting the surrounding landscape at a larger scale.

Photos courtesy of Kim Morrell

Saturday, February 13, 2010

The winter cometh

Our bus chugged mightily as it hauled us and our luggage and gear higher and higher through the winding roads of the Costa Rican mountains. By about 5:00 pm, we gone as far as the bus could take us and we pulled off at a dirt road leading into the depths of a mountainous valley. A small wooden cantina by the side of the road was our gateway to the winding road.

Most of the class began what was promised as a brief hike to the research station where we’d be staying for the next six nights and a few of us selflessly (we thought) volunteered to stay behind with our gear, which couldn’t all fit within the single available truck. Stoically, we began what we thought would be a wait of several minutes until the car returned for another load.

As we waited, we discussed the biodiversity of this unique area and our plans for the next week, gradually though, we began to notice our breath had become visible with each word that left our mouths. Looking around nervously, we saw a thick fog had begun to envelop the jungle canopy and was closing in around us. Although the instructors had told us what to expect of this region and urged us to pack jackets and wool caps for our stay here, it was still a shock to the system to be shivering while surrounded by a tropical forest. Those that had left before us were subjected to a litany of unflattering curses as we imagined them eating dinner and sharing rum around the fireplace.

We were to stay the next week in Cerro de la Muerte, a region of high elevation mountains in the southwestern portion of Costa Rica. During the day, residents experience comfortable weather typical of a warm spring day back home in the States, but as night falls, the fog rolls in and temperatures drop precipitously. Early travelers to the area were occasionally trapped by the cold and chilled enough to develop hypothermia and in some cases, death.

As the remaining light vanished, we dug through the remaining luggage for any of our winter clothing and I was pleased to see my hunter orange wool cap and light jacket hadn’t yet been transported to the station. Somewhat buffered by the rapidly dropping temperatures, we checked our watches and angrily exclaimed we had been waiting over an hour for the car to return. Over this time, we had unconsciously moved closer and closer to each other until we were practically huddled together in a tight circle, perhaps in the hope of conserving warmth.

Benoit begins to panic as the fog advances.

When a pair of headlights finally emerged from the now black road and revealed themselves to be from the course truck, we were prepared for martyrdom, permitting of course, if there was time after cursing out everyone else for being so inconsiderate in eating dinner while we heroically persevered in the cold to watch their luggage. But, what we heard from the driver Julio forced us to reexamine our condition.

The distance to our accommodations had been underestimated to the extent that those who had set off on the hike over an hour earlier had yet to reach it. Most of the other students were without their winter gear or flashlights and had been enduring on their long march to the station, still over a mile from the nearest person. Our condition seemed pretty mild in comparison, and we swallowed our angry tirades. Telling Julio to take some of the luggage and pick up the stragglers with any of the remaining room, we solemnly agreed together to wait once more for the truck to return. As it disappeared into the inky valley road, we soberly retreated to the nearby cantina and chipped away at our sobriety with toasts to group togetherness, feeling only slightly guilty about our newly appreciated good fortune.

Despite the signs, the burgers weren't really made of monkey.

Friday, February 12, 2010

An All Too Brief Stay in Cabo Blanco

It was a bittersweet departure from Palo Verde National Park. There was an incredible diversity and abundance of wildlife species, including large mammals known only from tropical regions, huge congregations of waterbirds in the vast marsh adjacent to our lodging, and it was our only home in Costa Rica up to that point. However, it was hot, it was dry, and sometimes it felt as though the dirt that often covered my body was being baked into my skin.

So, it was with excitement that we boarded our bus early in the morning to catch a ferry that would take across a small inlet of the Pacific Ocean to reach the Nicoya Peninsula, and eventually the San Miguel Biological Preserve in Cabo Blanco. Established in 1963, this conservation area is unusual in that it is afforded a degree of protection that is particularly rare; it is considered an absolute reserve, which means it is not open to the public (such as National Parks are, for example), collecting anything is strictly prohibited, and only a very few number of groups or individuals are allowed to enter the area in a given year. We were fortunate to be among the students allowed in.

The bus could only get so close to the reserve, so we mentally prepared ourselves for the hike as we got off the bus and into the sun. The heat wasn’t too much of a shock to the system, as the air conditioning in the bus had broken an hour earlier, leaving us sweating in silence. But, it was no comparison to the conditions we experienced as we hiked the several kilometers (a couple miles) to San Miguel, quickly becoming engulfed in forest; it was not long until my shirt was completely drenched in sweat, I could not have been wetter if I had just stepped out of the shower.

The surrounding forest was dense and excellent wildlife habitat; we passed directly under a lounging howler monkey who lazily hooted at our intrusion.

As we came closer to the preserve, we could hear the Pacific Ocean lapping against the shores and we looked forward to the promised opportunity to go snorkeling, a luxury many of us had looked forward to after field work in Palo Verde. As we crossed a small freshwater stream leading into the ocean, we noticed a small troop of capuchin monkeys drinking from the flowing water, watching us curiously as they sated their thirst.

After finally reaching the preserve, we were served fruit juice and oriented to the site, highlights of which included a plea that we hand over any snacks we may have hidden with our luggage. Their stated intent was to dissuade ravenous coatis and raccoons from raiding our living quarters, though our suspicion that we were covertly booked at a weight reeducation facility was only reinforced as we sweated through the next day’s scheduled hikes. We were also informed that the small staff does its best to live in harmony with the resident wildlife, to the point that they try to avoid making noises or showing their teeth to nearby monkeys, who might take these actions as threat displays. This caused us much distress as we attempted to conform to their policy while brushing our teeth each morning.

Upon exploring the maze of vines and forest around our cabin, I was distracted by the sound of rustling within the dry leaves on the ground. After fruitlessly searching for several minutes for the culprit, assumed to be a small lizard or bird, I realized I was hearing pieces of bark falling from the sky. Upon looking upwards, I immediately noticed a tamandua (black and yellow anteater) foraging for food, not disturbed in the least by my presence.

It was an animal (I presume the same animal) that was seen the next day in the same area.

The short path from the cabin to the ocean was densely forested and opened suddenly onto the beach. Upon turning around, there was no sign of the nearby cabin and little indication there was even a path.

The sand was alive with hermit crabs, dozens if not hundreds of them within view at any given time. They carpeted the ground with their pea-sized bodies, making the entire beach appear as if it was moving.

Watching them was like playing a game of red light green light. When I was stationary, the crabs would carry on their business, crawling back and forth following marching orders only they knew. When I made even slight movements however, all the crabs surrounding me would simultaneously freeze, motionless except for perhaps the occasional and brief rocking of their shells as a crab quickly retreated within. Only a few moments would pass though, before they resumed their travels.

We spent only three nights at Cabo Blanco and they went quickly. Given limited assignments aside from workshops designed to introduce us to the local plant diversity and facilitate identification of marine gastropods (snails, barnacles, conchs, etc), we were free to spend our time snorkeling in an adjacent lagoon (which produced sightings of Hawksbill Sea Turtles, eels, and a diverse assortment of fish) or resting within hammocks.

Rain drizzling down upon us in the pre-dawn darkness was an unwelcome development as we hiked out of Cabo Blanco, especially considering the thirteen hours of traveling that was ahead of me before I reached our next site. But, it’d be somewhat dishonest of me if I tried too vigorously to make you feel sorry for me because of my stay on the Pacific coast of the Nicoya Peninsula.

The temperatures drop so low that you quickly forget you’re in the tropics when the fog rolls in over the high elevation mountains in southwestern Costa Rica, our next stop on our voyage through the country. The quick onset of the cold nights was dangerous enough to easily kill early settlers, leading to the region’s ominous moniker, Cerro de les Muerte (Hills of Death).

Kelly, Benoit says hello.

Thursday, February 4, 2010

The Land Iguanas that Time Forgot

Spiny-tailed Iguanas are a common sight around the Palo Verde Research Station. They are one of the few animals you can reliably find in the heat of the mid-day sun. These are big animals, reminiscent of dinosaurs as they haul their three-four foot long bodies across the grounds.

Males must live a stressful life, their entire day is spent proving their worth to females while simultaneously trying to intimidate any other males within sight. They are commonly engaged in dominance displays, which involve vigorous head bobbing. Some males will try to find the highest point in the area, perhaps in the hope their display will be more visible to any other nearby lizards.
Typically relatively skittish creatures (for their size), the lizards around the station are accustomed to humans and allowed me to get relatively close for pictures. They may appear vicious but these animals are generally herbivorous. Though they're mostly a danger only to leaves and fruit, any attempt to capture them would result in vigorous tail thrashing and biting, and potentially severe injuries.

At evening, when there territorial displays are complete, they will retreat into burrows and other holes to wait for the next day to arrive, when they start all over again.

How many ticks can you find on this animal?

We will be leaving Palo Verde early tomorrow morning. For the next several days we will be at Cabos Blancos, an isolated site along the Pacific Ocean, where we will explore the unique habitats and perhaps fit in time for snorkeling and tidal pool exploration. Afterwards, we will travel to Cuerro de la Muerte, a high elevation mountain site where the dominant habitat type is oak woodlands, I've been told it will remind me of back home. We were assured we'd need thermal underwear, a wool cap, and a jacket for nights at this site...In Costa Rica. At both sites (nine total days), I expect to be without phone or internet access.

Monkeys of Palo Verde

As far as I can tell, there are three species of monkeys to be found within Palo Verde National Park. White-faced capuchins are encountered regularly within the forests surrounding the research station. You might hear them before you see them, chirping as they work their way through the trees. These monkeys typically are found in groups, although I've seen some monkeys traveling in pairs.
Black Howler Monkeys can also be seen somewhat predictably, lounging in the treetops or foraging for fruit. Although they get their name from their loud calls, which are often heard early in the morning, I have yet to be woken up by these beasts at this site. Though, on several occasions, I've heard them hooting in the distance in the middle of the day.

Spider Monkeys aren't as frequently seen, and I was somewhat surprised to see them here in this dry forest. Rightly or wrongly, I had associated them with habitats that receive more rain. But, on the walk back to the station from the Rio Tempisque, I came across a troop traveling quickly through the trees to a mango tree, where they feasted noisily and loudly. A small group of Howlers was displaced by the larger and more boisterous Spider Monkeys.

I had to dodge sticks and leaves falling from the foraging monkeys as I took their pictures.

This is part of a continuing series of my travels through Costa Rica as a component of a Tropical Biology Course offered by the Organization for Tropical Studies.

Wednesday, February 3, 2010

Palo Verde National Park

For about the last ten days, I’ve been staying at Palo Verde National Park in Guanacaste Province, Costa Rica, one of the country’s 26 national parks. This is the first stop on our voyage (a Tropical Biology course offered through the Organization for Tropical Studies) through the country, and we stay here longer than any other site, save one. But our time here is nearly up.

When most people imagine tropical forests, they picture the lush jungles of the Amazon rainforest. There are some areas in Costa Rica that superficially resemble these jungles, and we’ll be visiting some later (with their yards of annual rainfall). But not all tropical areas receive a lot of rain (think deserts). Forests in these areas are called tropical dry forests, and they’re one of the most endangered habitat types in the world. Typified by deciduous trees, much of the tropical dry forests in Central America have been converted to agriculture or land for cattle grazing; it’s thought less than 1% of its original extent remains. Palo Verde National Park contains one of the last chunks.

Afternoons are oppressively hot, the tropical sun beats down on us relentlessly. If you want to spend any time outside, suntan lotion isn’t a luxury, it’s a necessity. Since it’s now the dry season, many of the trees have dropped their leaves; so even when in the forest it is very hot and dry with little shade. The brittle leaves on the ground crack with each step, making it difficult to sneak up on wildlife.

Mornings and nights are surprisingly comfortable, the sun sets quickly closer to the equator, and soon after dinner it is as dark as it will be all night. Cool and refreshing winds bombard you, though any physical activity is still sure to result in considerable sweating.

Ironically, though an extremely hot and dry area, Palo Verde contains one of the most important wetlands in this part of the world.

The Rio Tempisque (where I previously spotted the monster crocs) runs through the park, and where it seasonally overflows (not this time of year), vast marshes form. Over the following months, the water level in the marsh will slowly dissipate and evaporate until the marsh is eventually is reduced to isolated puddles.
Many have remarked the water seems scarcer each day we’re here. But in the meantime, migratory waterbirds congregate by the thousands, including large wading birds like Roseate Spoonbills and Wood Storks. So many Black-bellied Whistling Ducks depend on this wetland that both environmental and hunting organizations consider this a priority area for conservation.

The marsh has been overrun with dense cattails that reduce its appeal to waterfowl, in decades past these cattails were controlled through burning and cattle grazing, but neither is a feasible option now. Burning is not advisable due to the dry nature of the surrounding forest, it hasn’t been adapted to fire and if the flames escape from the marsh it could be catastrophic. On the other hand, so many cattle would be required to maintain the open marsh that the place would be overrun with them. As it is there are a limited amount of cows that are kept in the park, in the hopes they at least help keep the cattail in check. Though not a particularly effective strategy, allowing some cows to graze here allows the park to maintain good public relations with some of the nearby residents.

For the last few days, I’ve spent most of the daylight hours attending lectures here, conducting some small research projects, and writing up the results; but nights are generally free to explore. This is when I’ve made some of the more exciting discoveries. If you spent any time on my blog here, you know I have a passion for reptiles, but no self respecting wildlife biologist doesn’t get excited at the prospect of finding charismatic or large mammals.

A few days ago, while helping another student catch insects for their project, I looked up within a tangle of branches and noticed what initially appeared to be a medium-sized rodent. Closer and more intent inspection revealed the animal appeared to be a marsupial.

Later confirmed as a Mexican Mouse Opossum, I am pleased with my attempt to immortalize it in a photograph. I proudly exclaimed to have found the most attractive opossum in the region. Later that same night, I found the ugliest.

A few snakes, brought to the lecture room earlier so we could learn how to identify them, had to be released. Hoping I could get a few natural shots of these animals, I volunteered to let them go. Being nocturnal animals though, the responsible thing was to release them at night. So, I trudged down the dark road to the area where they had been captured the night before, peering into the surrounding woods with my flashlight at every snapped branch, real or imagined. As is typical of when I take dark walks in the jungle, my thoughts quickly drifted to large predators. On my way back from the release site, as I was imagining if I would be killed instantly during a jaguar attack or if I’d be alive as it dragged me back to a secluded area to eat me, I was suddenly confronted by a pair of eyes reflected back at me in the road. At the distant end of the area illuminated by my fading flashlight, the rational part of my brain reassured me that this animal was too small to be a jaguar capable of killing me. But, the insane part of my membrane wondered whether this was perhaps a cub serving to distract me while mom snuck forward menacingly.

The little creature and I stood frozen in the road, looking at each other for several seconds while we sized each other up. When I had collected my thoughts and settled down I recognized it as a common opossum. Picture one of our Virginia Opossums back home and then imagine one that really needs a bath, and you’ll have a pretty good idea of the dirty little creature that stood before me. It eventually realized it had had enough of looking at my mug, and it scurried away into the underbrush.

A nearby spring in the surrounding limestone outcrops is also a good place to see wildlife; the various species congregate at these water sources at night, especially during the dry season. I’ve seen White-tailed Deer and Raccoons, the same species we have in the States, in the general vicinity of the spring. But I’ve also spotted some more exotic species including Coatis, Collared Peccaries, Paca, and my personal favorite, a Tamandua, a yellow and black arboreal anteater.

Collared Peccaries

Bats cruise through the trees, their wings seem to flap in slow motion as they hunt the insects attracted to my headlamp. You could reach out and touch one, though I'm not sure why you'd want to.