Dart poison frog
6/14/11—Soltis Center—87F
I was awakened around 4 am by a heavy rainstorm and the cries of howler monkeys. Their loud, bass, guttural roars echoed through the surrounding valley as they hailed the coming day, or perhaps they were just annoyed about getting drenched. The morning mist slowly poured over the ridgeline. Wispy puffs of smoky cloud crawled over the trees, enshrouding them in a grey-white veil of mystery and mystique. Who knows what lie beyond the wall of white?
We began our search for birds around 5:30, just as the light began to fill the valley. The golden rays of sunlight dripped through the tree branches as it filled every crack and crevice that it could through the thick forest canopy. As it reached the roots, the sunlight seemed to whisper to the trees, “Old sleepers, awake.” And as it did so, the trees seemed began to creek like old men awaking from a deep slumber. As the sunlight became more intense, however, they began to dance, swaying slightly back and forth in the breeze.
We spotted a plain xenops, a smoky-brown woodpecker, black-faced grosbeak, tawny capped euphonia. We were also blessed by the presence of all three species of honeycreepers: the green, red-legged, and shining. Their bright colors beautifully adorned the trees as they flitted from branch to branch. Bryan made an amazing spot of a short tailed hawk, perhaps the same one that was badgering a group of swifts twirling like fish, high in the sky, yesterday. In the forest, several wedge-billed woodcreepers flashed past, displaying their bright rust colored feathers as they landed on a tree and made their way up the trunk in search of insects. The secondary forest was extremely thick, with vegetation creating a continuous green curtain stretching from the top of the canopy to the forest floor. We moved in a silent line between the trees. These bastions could easily be the grandest of the columns in Muir’s cathedral of nature, as their wide buttress roots provide stability and are as intricate as a craftsman’s work. Nature truly is a wonderful sculptor. On our way up, we spotted a white-fronted nunbird. He swooped onto the branch of an almost as long as his head. He flipped it up pensively, catching it in his beak several times, as if deciding how he should go about eating his huge catch.
Green eyelash viper.
Upon crossing the stream, we noticed a green eyelash viper was sitting curled up on a nearby log. It did not seem to react at all to our presence. It was a gorgeous green eyelash viper, by far the largest one I had ever seen. It coiled, annoyed at our intrusion into its abode. It was a lime green, perfectly camouflaging it in the trees, with splotches of a deep blood red on its back. Its belly was striped white and red like a candy cane. We made our way slowly to the clearing. This was fantastic territory for terciopelos. We heard a rustle in the dry grass ahead of us. Perhaps it was a rodent, perhaps …
Upon our return to the Center, I spotted an unruly gang of keel-billed toucans fly from tree to tree. They chattered noisily, “Trukk, trukk. Trukk, trukk.” After breakfast, we suited up to enter the forest. Realizing the large snake presence of this area, many people elected to wear snake gaiters. Two girls, both in shorts and flip flops started down the trail ahead of us. Not exactly rainforest appropriate clothing. And sure enough, upon moving down the trail, a small tan and dark brown patterned snake slithered across the trail and into the forest underbrush. It was likely a false fer-de-lance, but there is little room for likelies when it comes to snakes. Our team cleared a trail to the site where we wanted to place our sap flow sensors. On the way, Kelly Lemmons spotted a gorgeous rufous motmot sitting calmly in the forest understory. His iridescent copper head and turquoise tail shone like a polished stone. His tail was picked clean, as motmots will pick their tail feathers, leaving just a small group of feathers at the very end, giving their tail the appearance of a pendulum on a clock, rocking back and forth.
We made our way to the center of our 30 meter diameter plot. We marked trees, measured their distance to the center, their height, and their dbh to properly characterize the plot. Tree identification was still a large problem because of the similarity between trees. In an effort to aid Kevin, I scurried up some of the small trees to cut down some leaf samples. Unfortunately, I was not able to do any roped climbing. The highest tree we measured was around 35 meters tall. This giant would be an excellent candidate for a double-roped climb, allowing me a bird’s eye view of the surrounding hillside. Alas, I had no rope and no harness. We continued working for several hours in the hot, humid morning and returned just before noon.
Josh and Kaitlin scouted out potential sites for our fog collectors and identified a need for some macheteros. In the afternoon they learned firsthand about the obstacles of doing research in the tropics. Josh went on an epic trip to the hardware store and learned that screen framing does not exist in Costa Rica. Kaitlin attempted to take some particle count samples, but after braving the snakes and cutting her way through the field, the skies chose to open just as she began taking data, forcing her to abort the trip.
In the afternoon, we compiled the data and tried to determine in which trees we wanted to insert sap flow sensors to measure transpiration rates. A large rainstorm moved in from the east. Several dark grey clouds skirted around to the south of the Center, but eventually, one hit us dead on. We could see a clear line where the rain was falling. The wall of water moved closer and closer until it finally hit us. The toucans and brown jays perched in nearby cecropia trees squawked loudly and made haste to escape the rains. The bananaquit hopping in the porterweed amidst the hummingbirds beat a hasty retreat as well. Huge raindrops fell on our metal roof. The satisfying plinks of raindrops turned into a low roar as the deluge let pour. The rains fell steadily for several hours, before abating.
After the rains, Bryan and I went into the forest for a night hike. We came upon several Common Parique, whose gleaming eyes shone hot pink in our flashlights and flew further away as we moved closer. We made our way into the forest slowly. Every vine seemed to slither and every water droplet reflection was an eye. Our senses were heightened as we walked into the dark forest.
We also spotted a column of leaf cutter ants marching steadily into the forest and back. These splendid foot soldiers are true wonders. They are agriculturalists. They do not eat the leaves which they carry, but instead use it to cultivate a fungus. This fungus has never been found outside of the leaf cutter ant nests. We went to the frog pond. There, we hoped to find the origin of the cacophony of frog calls. Despite their numbers, the frogs were difficult to spot. I finally found one high up in a tree. In an effort to find a better angle from which to view him, I stepped a few paces back. Then, I saw one of the most amazing natural spectacles to which I have ever been privileged to watch.
The frog and the snake
A vine snake, tail wrapped around the branch of a sapling, had bitten a red-eyed tree frog’s foot. As the tree frog struggled, we noticed that there was a male on the back of the female, meaning that the frog was caught during the act. Tthe male frog dropped from the female’s back, as if sensing that it must now depart. The frog kicked, climbed up the snake’s body, which was now struggling to hold on to its prey, and dropped, in an effort to jar its way out of the snake’s grasp. We thought that the tree frog may have a chance to escape, as it seemed to be so much bigger than the snake. The snake tried to lift the frog to a higher branch, but could not due to the frog’s weight. The snake tried this Sisyphean task several times, before deciding to attempt to swallow the frog in mid-air. Somehow, the snake managed to swallow both of the tree frog’s legs. We watched this somewhat disturbing natural phenomenon with rapt attention, only departing to find more observers, and obtain a better camera, as the long, muscular, blue-green legs disappeared into the snake’s mouth.
Two pairs of eyes - the snake's just behind the frog's.
Observing the epic battle seemed a bit macabre. This was, in all likelihood, the last moments of the frog’s life, and here we stood, staring at its bright red eyes as they slowly closed. After the better part of an hour, the snake had swallowed all of the frog’s legs. After some difficulty it moved past the blue and yellow striped hips of the frog. It was at the widest part of the frog’s belly, and it seemed that the snake may have bitten off more than he could chew (snakes, however, don’t chew). However, the snake can separate the bones in its skull and unhinge its jaw in order to swallow things that are far greater in size than itself. Snakes can also exude their wind pipe so they do not choke when swallowing their prey.
During this battle, we also found many more snakes and frogs near the pond, but none of them could turn our attention away from the event unfolding in the tree. Soon, a bubble formed on the frog’s throat; several drops of blood fell from the frog. The frog’s eyes bulged and closed. The snake was trying to squeeze the frog’s abdomen to force its front legs down, which were the only obstacle to the snake getting a meal. Eventually, the legs gave way, the frog’s bright orange colored feet disappeared into the snake’s mouth. The snake’s body was so stretched by the size of the frog that one could still see the brightly colored frog’s legs and sides through the skin of the snake. Nearly two hours after the ordeal began; all that was left to see of the frog was the very top of its head. At this point, the snake coiled itself more around the branch, pulled the frog’s weight up with a Herculean effort, and finished its dinner.
Thus, the snake had its monthly meal. One may be inclined to side with the frog, however, there are many tree frogs in this forest and that the snake must also eat to survive must be made. Thus, the flow of energy through this complex web of interactions continued.