Day 6- Carara National Park, Canopy Hike, and the Search for the Scarlet Macaws

Another early rise for morning birding to start off the day. Following breakfast, we traveled to Carara National Park to experience the biodiversity in a transitional forest- Pacific humid tropical rainforest and dry tropical forest. This blend creates an “eco tone” which gives Carara its biodiversity. The symbol of the park is the scarlet macaw. Scarlet macaw breeding pairs are found here as well as many other birds which makes the park a bird watchers paradise.

Carara is home to half of Costa Rica’s animal species. It’s transition zone forests are in what is called Costa Rica’s “Goldilocks Zone”- not too sunny, not too cloudy, not too wet, and not too dry- it is a zone just right for many forest plant and animals.

Jimmy, our walking nature Wikipedia, again pointed out so many interesting things- too many to list and describe here. This mound was interesting. Turns out it is the “garbage heap” of the leaf cutter ants, that deposit the debris from their underground nests on this mound.

This fragile looking plant with thorns is also very interesting. It is a swollen thorn acacia that has an interesting symbiotic relationship with stinging ants. The acacia lacks the chemical defenses that may plants have in the rainforest. Instead it depends on colonies of ants that live inside its hollow thorns to protect it. The plant benefits from the protection against insects and browsing mammals and the ants benefit from the food provided by the acacia. The plant produces nectar at the base of the stalk right above the thorn and tiny granules produced at the tip of the leaflets feed the ants. Jimmy cut into a thorn to show us how an ant lives inside.

The shrub that dominates the understory in the park is called the cafecilio and is only found in the central Pacific lowlands. Interestingly, scientists do not know a lot about this mysterious plant- why it grows where it does, what pollinates it, or how its seeds are spread. It makes fruits but seedlings are rarely found. Research is underway to learn more about this endemic species and whether it needs protection.

Jimmy pointed out the different roots that support trees in the rainforest such as prop roots and buttress roots that spread out widely to support large tall trees such as the Ficus and Kapok trees. Roots don’t penetrate the poor tropical soils deeply enough to anchor the tree so the buttresses provide the added stability. They look like “fins” on the base of the tree trunk. The larger the diameter of the tree, the larger the buttresses. The height of the buttresses, how it splits, and its shape help identify the species of tree. Good STEM example of how engineering mimics nature in the design of buildings. Reminds me of the flying buttresses in medieval cathedrals. Jimmy also pointed out the pools of water in the indentations of the buttress roots where you can sometimes find frog eggs.

Jimmy posed the question, “Why can’t tree rings be used to age large trees” such as the immense kapok tree. It led to an interesting discussion of seasonality and how tropical trees don’t produce the annual rings like the trees in temperate and northern forests since there is no definitive change between seasons.

Jimmy pointed out the “tree huggers” of the forest, strangler figs which can be found encircling large trees. These vines do not actually “strangle” the tree. The tree becomes constricted as it grows within the encircling vines. 

Looking around the forest we could see many types of vines, including ones with leaves flattened against a tree trunk as if it were glued on.

From the sun-drenched crowns of the trees to the moist forest floor, each layer has its own specialized plants and animals that live there. The epiphytes, plants that live upon trees, are particularly interesting. Leaves of aroids trap sunlight while their roots grow down to the soil where they absorb needed nutrients. Orchids have root like structures that swell and retain liquid and bromeliad leaves spiral to store water.

Josh’s sharp eyes spotted a walking stick, my favorite insect! Amazing how they are so adapted to look like twigs.

One of the largest trees in the tropical dry forest is the wild cashew tree. It can reach heights of 160 feet and diameters of 10 feet. The seeds are dispersed by fruit eating bats, which eat the fleshy part of the fruit and let the rest fall to the forest floor where the seeds germinate.

We crossed over a bridge and it was here on the trail where the tropical dry forest, typical of Costa Rica’s North Pacific region, meets the very moist forest of the South Pacific. Because of this we encountered species from both forests here.

Besides the leaf cutter ants, there are several other varieties of these social insects in the Costa Rican forests. The bullet ant, which is quite large, has the most painful bite of any ant species. 

Jimmy carefully and deftly picked up an army ant and showed us its enlarged mandibles. These pincershave been used in the wild as temporary sutures. When someone got a deep cut, ants were placed on the sides of the wound where they bit the flesh, pulling it together as a stitch would, with their mandibles. The body of the ant was then pinched off leaving the mandibles holding the wound together. Interesting STEM example of using nature to solve a problem.

Jimmy pointed out two other interesting insects, including a stinkbug.

Besides the plants and animals, there is also a wide variety of fungi in different shapes and colors. These decomposers are the recyclers of the forest.

We also saw more agoutis and the black and green poison dart frog. The coloration differed from the same frog we saw in Sarapiqui as it had more black and less green. We saw a bat sleeping on a tree and an interesting type of lizard.

During our hike in the Carara National Park we could hear the squawking of the scarlet macaws but it was hard to spot them amid the vegetation of the dense forest. As our hike in the forest came to an end without sighting the macaw, our ever resourceful guide, Jimmy, had our driver head to the coast and a nearby village, where we might see macaws out in the open trees. We walked along a stretch of Pacific coast, where fishermen banked their boats but didn’t spot any scarlet macaws.

Driving back through the village Jimmy spotted a large almond tree, favorite food of macaws. sure enough, there were four macaws in the tree and pairs flying overhead. What a treat to see these beautiful, intelligent, long-lived birds who deserve to live free and not be victims of the exotic pet trade.

On our way back to the hotel for lunch, Jimmy stopped at a supermarket so we could buy bags of Costa Rican coffees and snacks. Yucca chips have now trumped potato chips as a favorite salty snack!

As I was paying for my coffee and snacks, Jimmy pointed out a large dried beetle on a shelf behind the cashier. He knew I was on a quest to find a rhinoceros beetle so this was close enough for now. The cashier let me hold it. It was as big as my hand!

After lunch at the Hotel Villa Lapas, Jimmy took the group on a canopy hike, over the hotel’s suspended canopy walkways where you could get a 360 view of the forest from the mid canopy. 

Cane toad

Julie Gardin, one of our fellow travelers from Nevada who was with us in India and Iceland, lives part time in this area of Costa Rica, helping care for her granddaughter who was born in and lives in Costa Rica. It was such a pleasure to meet Julie’s family and catch up with her over dinner. Traveling together is a great way to meet new friends and form friendships that last well after the trip. We are so glad many of our fellow travelers keep in touch and return to travel together on new trips.

After dinner, Jimmy took us on a night walk along the Hotel’s pools to look for nocturnal frogs and other animals. We spotted several red eyed tree frogs, golden tree frogs, another type of large frog, and a water snake. Katie mastered the sound of a mating frog and engaged in back and forth "croaking"with her frog “mate”!

We saw tree frog eggs deposited on the leaves of the plants and zooming in closely, we could see the tadpoles in the eggs.

It was another remarkable day filled with amazing sights and sounds. We wonder what tomorrow will bring....

Day 5-La Paz Waterfall Gardens and Tarcoles River

With our luggage loaded and one last early morning birding walk with Jimmy, we enjoyed our last breakfast at the Selva Verde Lodge. Gus, who seems to be the “hospitality guy” at the lodge, was particularly enamored with our group. On our last morning he walked over to give Page “dessert for breakfast”, having saved her favorite coconut dessert for her, and he made a warm molasses drink for Carolyn, Jim, and Joyce and showed them how to dunk biscuits in it. We said our goodbyes to Gus- such a character!

Off we drove to the La Paz Waterfalls and Gardens, a privately owned popular attraction in Costa Rica famous for its waterfalls and lush botanical gardens. We pulled off to the side of the road on the way there to watch a troop of howler monkeys.

La Paz is a waterfall located immediately alongside a road that leads to and from Sarapiqui. We stopped on the road to get a glimpse of the waterfall and watched Jessica and Josh have some fun with their camera. Josh sure was thirsty!

We arrived at La Paz and were greeted with a beautiful view of the mist rising from the rainforest.

We hiked the waterfall trails in a steep canyon, stopping at each of the viewing platforms to view 5 waterfalls. On one of the platforms we were so close we could touch the backside of the waterfall (and get a little wet in the process!)

We enjoyed some time to wander around the gardens, view hummingbirds and butterflies and see some of the birds and animals that were rescued from injury or confiscated as pets and can’t be released back into the wild.

We enjoyed a delicious buffet lunch and then it was back on the road, headed to Carara.

On our way to Carara, we encountered a bovine traffic jam! 

We stopped at the Tarcoles River. Although the river is murky, it is an important watershed area and what makes it interesting is that it houses one of the world's largest crocodile populations with about 25 crocs per square kilometer and 2,000 crocs in the area. They grow to 15 feet or more!  There are also many species of birds and reptiles in the watershed area.

We donned our life jackets and boarded a boat for a 2 hour cruise through the river and its branches leading to the ocean, looking for crocs and birds. 

Jimmy and the boat operator pointed out so many birds and interesting animals along the way. We spotted a massive croc named Tyson. Our boat operator is one of the reputable guides who does not feed the crocs to entertain tourists. Like Jimmy, he is an astute observer of nature.

Boating through the river and the mangrove area we were struck by the silence- the only sounds were the sounds of birds. The boat billed heron was a particularly interesting bird. Jimmy described it as a bird with a shoe on its face! We saw several iguanas, basilisks, and crabs. Great blue herons, green herons, cormorants, spoonbills, ibises, tiny kingfishers, osprey, and many more birds, including several scarlet macaws flying high overhead. You can easily distinguish them from other birds flying overhead as they always fly in pairs or triads, they flap their wings and do not soar, and have a streamlined shape when flying. 

After our boat trip we arrived at the Villa Lapas Hotel for dinner, followed by a passionate lecture on saving the Scarlet Macaw which raised our anticipation for spotting scarlet macaws tomorrow.

Day 4-School Visit and La Selva Biological Research Station

Several of us rose early to go on a morning birding walk with Jimmy. A chestnut billed toucan was spotted high in a tree.

 

We crossed the road to explore a new area. Jimmy pointed out several birds and interesting plants; then suddenly, there was a rustling in the trees overhead. We watched a troop of capuchin monkeys feeding on leaves and fruits, leaping from branch to branch. Jimmy warned us: “If a monkey smiles at you, don’t smile back!” Showing your teeth is a sign of aggression.

Returning to the Selva Verde Lodge for breakfast, we were greeted by a large iguana sunning on a branch outside the dining area.  

After breakfast we walked to the Sarapiqui Learning Center where the director explained the variety of classes and learning resources they provide for the local community, including adult education. 

We walked to the local school where we met with a 6th grade teacher in the computer lab (only room in the school with air conditioning) and her students (no photos allowed of students). In a round robin, each student shared what they wanted to do for a career. The top answers were policeman, doctor, and teacher. Asked what their favorite school subject was, mathematics and science came out on top! We had a nice conversation with the teacher about the Costa Rican education system and its challenges. Page presented her with one of her recent books, translated in Spanish.

Returning to the lodge, we had some time to wander around the beautiful grounds, marveling at the fruits and flowers of the rainforest plants and the ambiance of staying in a rainforest ecolodge. 

Our afternoon was spent at the La Selva Biological Research Station. La Selva is a key research and training site for scientists. We were met by a Joel, a La Selva guide, brother of Eduardo (who taught us about chocolate). He started off our walk by giving us some background on La Selva.

Established in 1968, La Selva has1,600 hectares of well-preserved old-growth and recovering wet lowland tropical forest that abuts the Braulio Carrillo National Park. The 4 to 6 km wide forested corridor that connects La Selva at 35 m above sea level to the Barva Volcano at 2,906 m is one of the best-preserved elevational gradients in the tropics.

We began our afternoon hike by crossing the footbridge over the river to enter the forest trails.

Like Jimmy, our La Selva guide has a sixth sense when it comes to spotting birds and other organisms. Between the two of them, with their acute sense of observation, we added over 50 more species of plants and animals to our biodiversity list, including many birds viewed through the birding scopes and binoculars. Jimmy not only spots and identifies plant and animal species for us, he also explains the ecological relationships. 

One of the coolest finds was when Joel spotted a group of tiny Honduran tent making bats sleeping under a broad banana-like leaf. One by one we stepped into the forest and viewed them as Joel held a mirror under the leaf.

There was so much to see. Besides the bats, a partial list of our animal sightings included two-toed sloth, howler monkeys, black guan, iguanas, northern bark woodpecker, trogan, jackamar, red lore parrot, collared peccary, agouti, green and black poison dart frog, bullet ant, chestnut billed toucan, black and white owl, great currasow, and so much more!

After our two hour hike in the forest, we returned to the Biological Station where a young research manager took us on a tour of the labs and explained the research programs and opportunities at La Selva.

La Selva has some of the longest running ecological data sets in the tropics, spanning up to 40+ years. Long-term research of terrestrial and aquatic ecosystems has generated data on nutrient cycling, plant and animal demography (e.g. birds, trees, frogs, etc.), community interactions, and their responses to a changing climate. Key research areas include:Forest dynamics and nutrient cycling, forest succession, global change and human-nature interaction, agroecology, and aquatic ecosystems. Over the years, La Selva has hosted several international student researchers seeking to use Selva Verde as their field site.

After our visit to the labs, we emerged from the facilities to a crashing sound coming from the forest perimeter. Suddenly a pack of collared peccaries came out of the forest to feed on the grass. Not only could we see them up close, we could smell them as well!

Looking up, Jimmy spotted a green parrot through the scope. 

Lots to see looking up but there is just as much to observe looking on the ground. We watched a long trail of leaf cutter ants. It was amusing to watch everyone stoop down to photograph these tiny, strong denizens of the forest floor. 

Jimmy showed us the tree they were coming down where they cut pieces of leaves from the top of the tree and climb down to the ground, following a long pheromone trail, until they get to their underground nest where the leaves feed a fungus which in turn provides food for the colony. Another example of mutualistic symbiosis. Jimmy focused the scope so we could actually see the ants cutting the leaves. In proportion to the size of their bodies, these are heavy lifters indeed!

Watch a time lapse video of the leaf cutter ants.

La Selva was definitely a highlight of the trip so far. It was a real life example of the John Muir quote, “Tug on anything in nature and you will find it connected to everything else.”

Following dinner, we met in the bar for a talk by one of the researchers at La Selva, collaborating with researchers at the University of Georgia. The beer was on Jimmy this night (Thanks Jimmy!) and in a relaxed setting, we enjoyed a super engaging talk about stream ecology from a very animated scientist who obviously loves his work! He showed us instruments he uses to collect data on the chemistry of the water and collection of benthic insects. He collects long term pH and other data looking for shifts that explain what is happening over time in the area including effects of climate change. 

He showed us some tools he improvised including a device to suck up insects using the fan from a hair dryer and a water siphoning device made from a power drill. Great example of how science and technology (development of tools needed to do research) intertwine!

It was another STEMtastic day!