The study of natural history involves observing natural areas over a period of time. I have studied various areas before in a variety of biomes. Given the opportunity, for which I am grateful, I decided to carry out an observation in the Rain Forest of La Selva.

Our team decided to examine nature over the course of a day. I walked out on trail SOR to the 500-meter mark and walked out on to a field with an abandoned house. One team member was to join me and the other decided to work deeper in the forest.

11:35- Friday: Partially cloudy, and there are sounds of flowing river. I am sitting on a bank above the Rio Puerto Viejo River looking in a northward direction. There are howler monkeys making noise all around me. There is a slight breeze blowing the mosquitoes away from my face. The cicadas are singing their songs with shrill calls.

Two yellow butterflies fly together along the surface of the river. The cumulus clouds are drifting from the southeast. The howler monkeys have quieted down now. The temperature is 86 degrees F. The humidity is high.

I just saw two ants together on one branch on the ground and one was about 1,000 times larger than the other. I am amazed by the diversity of ants in La Selva.

The mosquitoes continue to buzz my head. I can see two monkeys behind me. Ahead on the river two black vultures soar over head. In the background I can hear the sounds of a truck on the highway. I hear a clucking birdcall and lots of birdcalls around me.

13:50- I have returned to the site after lunch. There are yellow butterflies around me. I saw 4 lined whiptail lizards on the trail as I walked out here. I count the cicada calls at 36 per minute. The temperature is 86 degrees F. A white-tailed bird, which I can’t quickly identify, flies by in an undulating flight.

14:22- A broad-billed Mot Mot, which I can’t see, is making its call. It sounds like a water pipe being used. The large white cumulus clouds are thickening and turning dark. Some creature is making sounds from the forest. I walk to the edge of the vegetation and stare in not seeing anything. I know that some animal is in there staring back at me. Behind me I can see the Mot Mot in the tree.

14:24- A black vulture flies over the river about 40 ft. above the surface of the water.

14:31- A human walks down to the edge of the river. He stands in the water for about ten minutes and then jumps into the water and drifts down the river with the current. I follow him with my binoculars for about 10 minutes and then he rounds the river’s bend and disappears. A flock of crow-like birds with yellow tails appears.

14:50- The howler monkeys arrive at the site. It begins to rain fairly hard. I notice that the some of the monkeys are laying down on the branches up in the fig tree and have fig leaves over their bodies to shelter them from the rain.

15:21- The rain lessons considerably now. Directly over me there is a howler monkey looking straight down at me as I lay on my back looking at him through the binoculars. He is no more than 15 feet away. Next to this monkey is another with a baby riding on her back. They are eating the figs. I count at least 8 howlers in two separate trees.

The temperature is now 85 degrees, but it seems cooler than that since the rains came.

There are now two howler monkeys coiled up in a fork of the branches of the fig tree. There look very cozy and seem to be quite content. I listen to the sounds again; the river, the trucks, the branches falling as the monkeys move around, the dripping water from the leaves in the trees.

15:53- The toucan flies away. I watch one monkey intensely and notice his every move. They are constantly scratching themselves, and I try to imagine the parasites that they may carry. Their fur has such a beautiful brown hue and their faces have folds above the eyes. I can’t help but notice the similarity between them and my self.

16:01- One monkey pees like crazy and then fondles himself for a while. A mother with a baby crosses from the fig tree into a Pentaclethera tree. They easily walk headfirst down the limbs. One monkey is pulling leaves off the fig tree and is eating them.

16:25- A small agouti wonders out of the woods and goes over to the abandoned house. I move from the river site up the hill so that I can get a better view. He sees me and runs away.

16:28- I notice a toucan in a tree and focus my binoculars on him. He works his way up the tree. There is a loud snort behind me and I turn to see three peccaries two feet behind me. I am startled and so are they. They give out warning huffs and run quickly back into the forest. I am now looking at 4 toucans in a row on a branch in a tree ahead of me. A cow begins bellowing in the background.

16:32- A single peccary comes back out of the forest. He almost walks right into me while snorting the ground. He grunts a loud grunt and returns to the forest.

16:33- My howlers begin to roar loudly for about 10 minutes. I park myself under the Pentaclethera tree to help me brace my neck so that I can watch the monkeys in the tree better. Two parakeet type birds fly overhead.

15:42- The Mot Mot continues with its song. There are more sounds of trucks from the highway.

16:47- It is starting to darken. A dog barks in the background

16:57- A beep, beep, beep sound comes from the forest. I think that I will call this bird the beep-beep bird. The monkeys move over to a fig tree by the river. Some are in the fig tree and some climb up into the higher Dipteryx tree.

17:00-The mosquitoes are everywhere. They continually buzz my head and I spend too much time shooing them away. The fruit is dropping around me like crazy now. There is some kind of bird way up in the cecropia tree causing it. It is like raining fruit.

17:08- Twelve peccaries in a row come out of the forest in a single file line and start feeding on the fruit under the palm. They walk right by me and don’t seem to notice me.

17:15-Squawking birds overhead in the tree scares the pigs and they snort the alarm. They stare at me, but continue to eat. The flies are really attacking me now. Five more pigs amble out of the forest. One walks out from the date tree and sniffs them as they come. The last pig out of the forest is met by this greeter pig who immediately chases it into the forest. The sniffer pig comes back out in a few minutes. The sniffer pig jumps up on a short palm and eats the middle out of it.

17:26- More sounds from the beep-beep bird. The pigs move on now all except for one who stays and just stares at me. He gives one final snort and runs off with the others. I leave for the night.

As I approach the site I can hear the howler monkeys yelling loudly. When I enter the clearing, they become silent. There is a whip-er-will sound coming from out of the forest. A slight mist hangs over the forest. Sweat already begins to roll down my back. The howlers sound like huge gorillas by the sound they make in moving from tree to tree. The temperature is 74 degrees F. Apparently the Howlers spent the night in the Dipteryx tree by the river. Flies buzz my head and one alights on my skin every so often. Overhead a monkey is eating his figs and leaves.

6:00- A mother monkey with a baby on her back moves from the fig tree across the branches to the Pentaclethera tree. The mist in the treetops paints an eerie picture. The cicadas are making their sounds softly in the background. There are lots of birdcalls.

6:11- The cow begins to bellow again. Howlers in the distance and making their yells, but my howlers are ignoring it.

6:15-The first rays of the sun are now hitting me directly. Overhead a monkey grabs a fig branch and pulls it close so that he can eat the figs off of it. For an instant I think the monkey has fallen, but it is just a large branch with leaves falling. I wonder how common it is for monkeys to fall.

6:18- A large yellow butterfly flutters into the opening. I notice a large ant (a bullet ant?) crawling on my leg and brush it off. A large yellow and green bee or fly flies and hovers directly in front of my face checking me out. It won’t go away, so I slap it down.

6:27- A long-tailed red squirrel is feeding on the dates of the palm. He peels off the skin with 3 or 4 bites and chews on the insides. He picks the fruit and holds it in his hands or just eats the fruit directly from the tree in the same manner. The water pipe bird calls again and the branches continue to crash to the ground from the monkeys.

6:36- Susan has been observing down at the river and walks up the hill to greet me. Neither one of us knew that the other had been there.

6:49- More insects are buzzing around now. A large black cicada-type insect attacks me. Figs continue to drop from above.

7:01- The monkeys, who have been fairly stationary, are now on the move. They move from the large Dipteryx tree, to the fig tree, the Pentaclethera tree and out of the study area. They move to another Dipteryx tree just outside the perimeter.

7:10- A monkey is again directly over me looking at me as I look at it through the binoculars. It begins to defecate and I move quickly out of the way. The monkey is making lots of gestures with its hands and is constantly stratching. These monkeys have no fear of leaping from tree to tree.

7:20- The Mot Mot bird flies off into the forest. The mosquitoes are getting worse. The temperature is 77 degrees F.

7:25- I notice the Doppler effect as a fly flies by my head. The broad-billed Mot Mot returns to his favorite spot on a branch of a tree by the river.

7:30- I get up to stretch and walk to the river. There are two guys on the island in the river throwing a measuring device in to the river and retrieving it. They jump on an inner tube and float down the river continuing to take measurements. I watch them round the bend of the river and disappear from sight.

7:50- A morpho butterfly flies by. Susan and I amble over to the deserted house to inspect it. There are lots of 4-lined whip-tail lizards darting around. We start to go in but notice the signs on the door. This is a site for a Soccopteryx bat research project. The researchers do not want any light to enter, so we leave the house. It seems like every object at La Selva is involved in some way with a research project.

8:21- We hear a pig snort. Susan jumps excitedly. Behind us Chris walks towards us telling us about a pig that just snorted at him. We exchange pig stories. There is a jay-like bird on the branch. It has a reddish head, a blue body, and there is a white tip on the tip of the beak. I recognize it at last as my friend, the Mot Mot. Lots of fruit continues to fall from the cecropia tree, but neither one of us can see the bird causing it to happen. There is a toucan feeding in the fig tree.

8:28- Toucans in the fig tree. What a fantastic looking bird, such a large colorful beak. I hear the beep-beep bird again. I see a monkey in the far-away Dipteryx tree move. The monkeys are getting harder to find, and I think they are moving away from the study site. The cicadas are chirping at 30-34 chirps per minute now.

8:43- A single pig comes out of the brush to eat the dates. He feeds himself for a few minutes and is joined by another 3 pigs. We talk among ourselves and the pigs don’t

8:53- Another single pig exits the forest and joins the others. They quickly leave and disappear into the forest on the other side of the abandoned house. We see another large ant and brush it away. We decide that things are pretty quiet at the study site now and decide to leave the area.

Study of a Natural Area

La Selva Biological Station

Costa Rica, July 2001

Dave Fletcher's Notes Susan Sprenke's Notes David Lesley's Notes