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Osa Conservation – Costa Rica Part 3: Wildlife Galore; The Rainforest Habitat, Species & R

You very quickly become part of the ‘Osa Family’ at Piro. A shared passion for wildlife and a desire to do something that will make a difference, pulls you together like no other experience. I was keen to see, and be part of, as much as I could in the short time I was at Osa and everyone was keen to share their work with me and to spend time with me, explaining all their research or conservation efforts. Knowing I was keen to see as much wildlife as possible meant that many were looking out for species and telling me when they were about!

Danny is studying Spider monkeys and pointed out the endangered Geoffrey’s Spider Monkeys that were around camp. The Geoffrey’s Spider Monkey (Ateles geoffroyi) that inhabits the Osa Peninsula has a major role in the forests on the peninsula: these charismatic creatures are both crucial for seed dispersal and also double as health indicators for forests. In the past 45 years, the Geoffroy’s spider monkey has declined by almost 50% and is now listed as endangered. It is vital we learn more about their ecology to prevent further decline. If the spider monkeys do affect the plant community, a conservation strategy could include translating the sleeping tree leaf litter to areas of the rainforest where there are no spider monkeys.

Danny is studying the effect spider monkeys have on the plant community structure for her undergraduate dissertation project at the University of Exeter. Spider monkeys are frugivores, meaning they eat a diet consisting predominantly of fruit. They settle to sleep at specific sleeping sites that also function as latrines, or communal toilets. Danny is  studying  sleeping sites to understand the effect spider monkeys may have in seed dispersal. Her dedication amazed me! Most of the time I was there, she was up between 3am and 4am to return to the sleeping sites she had identified late the night before. She works incredibly hard and I wish her all the best in her studies!

I was lucky enough to see a small group of these monkeys come into camp. Photography is often difficult due to them begin high in the trees. There is a lack of light in the deep foliage, so I was quite pleased with these images. Their prehensile tail acted like an additional arm and they often hung from their tail, whilst searching for food….


I was also lucky enough to see one of the other species in this area; the Central American Squirrel Monkey (Saimiri oerstedii). These were high in the trees alongside the road when I saw them. Their agility in the trees was incredible as they effortlessly clambered and leapt around in the highest boughs.


Although I heard and saw the howler monkeys, I did not manage a picture; they were far too high in the trees and obscured by foliage.

Another researcher I met was Hilary Brumberg;  the  coordinator of the Ríos Saludables (Healthy Rivers) program. Newly graduated, Hilary is undertaking some wonderful community projects based around the huge number of rivers that run through the region. Hilary travels around community sites, meeting dedicated conservationists and families who are interested in the effects of agriculture and roads on their neighborhood water source. The community members are given water testing kits and  are taught how to examine the river water quality. They examine both what is dissolved in the water (chemistry) and what is alive in the water (biology). They survey the rivers for  macroinvertebrates, whose presence indicate the health of the river because they are sensitive to pollution. While chemical monitoring provides a “snapshot” of the water quality at the time of sampling, macroinvertebrates tell a story about what is happening in the stream over a period of time.

Hilary took me and a fellow volunteer, Ethan, down to the river, to show us what her work involved. It was going to be the first time I could get the Olympus TG-5 camera I had been loaned, in the water! I was keen to get some interesting shots and to also provide Hilary with some pictures of her at work, for her presentations. It was a pretty idyllic setting….




I was keen to try some semi-aquatic shots… not as easy as I thought, but the crystal clear waters made underwater photography easier!




The camera was as brilliant underwater as it was above, giving me the opportunity to experiment both on macro and with video;


Upon capturing some invertebrates within Hilary’s nets, I tried out the microscope mode on the camera to see if we could get shots that would be good enough for ID purposes. ..

Hilary was impressed and will be using these images within her future presentations.


We headed back to camp for some lunch and I had some time to get out in the ground with my DSLR. There are lots of flowering plants around camp and it is full of butterflies; the sort you usually see in a butterfly park. Huge Blue Morpho drifted around like tissue paper, but avoided my camera. These species I photographed below were most common and it was so wonderful to watch such exotic looking species in the wild…


My afternoon was spent with Ruthmery Pillco Huarcaya. Ruth was Andy’s assistant in Peru and is a very valuable and experienced member of his team. Ruth’s work is varied and her research is mainly based around plants and botany. One of Ruth’s studies involves the native Vanilla. Costa Rica has approximately 12 species of vanilla, at least four of which are found around the Osa Conservation’s biological station and adjacent landscapes. Only two species are grown to produce commercial vanilla: V. planifolia and V. madagascariensis. Because the natural pollinators are unknown, pollination is performed by hand, and low levels of genetic diversity are expected in cultivated plants.  Ruth has been studying the pollinators, using trail cameras.

Ruth is also part of a huge project on regeneration and replanting. Many areas of the OSA were destroyed for farming and Osa Conservation projects are working hard to replant and regenerate large areas. Through various different experimental planting patterns, they will study how different species impact on the speed of regeneration and the species biodiversity. Ruth took me to the Osa Verde camp. Osa Verde is 10-acre working farm located on our Osa Verde property, a former cattle ranch that is being restored. So far,  10 hectares  this 500 acre property has been replanted and a wetland area has been restored. The vision for Finca Osa Verde is to create a model for the region, where  sustainable, integrated farming techniques can be demonstrated that can be easily adopted by local farmers – improving livelihoods and positively impacting the environment. Finca Osa Verde will also host international visitors who come to learn about and research tropical agro-ecology and sustainable agriculture principles.

Ruth showed me the huge areas where seeds, collected from the rainforest, are grown ready for replanting..



The whole area was bursting with life…. the leaf cutter ants being prolific. I am always captivated by these insects and their industrious activity along incredibly well-worn paths….



Leaf cutter ant communities are fascinating and consist of lots of different individuals, all of whom have different jobs. These are the guard ants, with their huge jaws. They patrol the paths, protecting the other ants…



The work and research here is simply astounding and there are so many opportunities for research scientists and volunteers alike.

Heading back to the track, to head back to Piro, we were able to watch some distant macaws feeding…


We also saw this roadside hawk with prey..


With the sun shining when we got back to camp, I took the opportunity to photograph some more insects. The site is just bursting with them, particularly dragonflies! There are some stunners! I am not sure what species these are, but I could have photographed them all day!


The day was not over… we had a real treat organised for the evening; a night swamp walk! Manwell, Research Assistant and Sea Turtle Program Coordinator, led the trip with some fellow volunteers.

Just before we went, we found this masked tree frog in camp. I photographed it with a head torch and the TG-5 and it was most obliging !








Clad in our waterproofs, wellies and head torch, we headed down to the swamp in darkness. The rainforest is a pretty incredible place in daylight. At night, it is even more special. With less visual input, your other senses seem heightened and the sounds are what hit you most! Moving into the swamp at night were were met with an orchestral barrage of calls. Insects and frogs called from all around and Manwell led us deeper into the area, water almost up to the top of our boots (and over Peggy’s boots!) Incredibly, Manwell seemed to have some kind of ‘frog radar’ ; being able to pinpoint these tiny amphibians on tiny branches and leaves. We were able to see a variety of frogs and I photographed these using the TG-5 with our headlamps, which was quite difficult. There were loads of tadpoles in the waters around our feet and tiny froglets, just venturing up onto sodden leaves. The red-eyed tree frog had to be a highlight!












Manwell also wanted to see if he could find a rare, tiny glass frog. Glass frogs are nocturnal and inhabit tropical and subtropical humid forest regions.  They are associated with riparian habitats where they reproduce by laying their eggs attached to the vegetation and other structures overhanging streams and rivers. We took a walk up the river before we got back to camp. This stunning blue crayfish was spotted by Manwell, as he searched the leaves for the tiny and elusive glass frog.


Incredibly, Manwell located one… a male protecting the cluster of opaque eggs on the underside of a leaf. Being incredibly careful not to disturb this tiny amphibian, we were able to take a couple of quick photos before heading back to camp.



The sights and sounds of that swamp at night will never leave me…. what a wonderful experience! I went to bed with a chorus of frog calls in my mind!

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