miércoles, 22 de mayo de 2013

Camera trapping in Payamino, by Xaali O'Reilly

Timburi Cocha Research Station
For the past 10 months, I have been living at the Timburi Cocha Research Station in Payamino, Ecuador. I'm here as part of my Zoology BSc with Industrial Placement degree at the University of Manchester (England), working as communications coordinator as well as conducting my own research project on the effect of forest regeneration and human activity on rainforest mammal diversity.

Payamino is owned and managed by an indigenous Kichwa community who have lived in the same location since at least the 1960's, when the semi-nomadic tribe settled to acquire property rights from the Ecuadorian government. As other native peoples of the Amazon, the Kichwa have been modifying the rainforest for hundreds, perhaps thousands, of years.

In Payamino people use a model of swidden agriculture, whereby a patch of forest is cleared, desired crops are planted, and the site is selectively weeded for a number of years. After this, the land is left to fallow, sometimes long enough for the forest to regrow to a great extent. This regrown forest is secondary forest, and is distinguishable from primary forest generally by its chaotic understory (or obviously cleared understory, sometimes), scarcity of large buttress root trees, and fewer well developed epiphytic communities.

Riverbed in primary forest.
With the Amazon becoming a conservation priority in recent years – due to its expanse and exceptionally rich biodiversity – international groups are continuously putting pressure on Latinamerican governments to enforce conservation measures to protect the world's largest remaining rainforest. However, if effective longterm conservation methods are to be developed, it is important that they are well informed and take into account the ecosystem dynamics of each habitat and what the threats to them are. In addition to this, it is important that conservation measures take into account resident human populations, because it does not look like human population growth is about to slow down any time soon, so simply keeping people out of nature does not seem like a plausible or stable approach.

Getting a twig out of the way of a camera trap. If any
camera-trappers are concerned about the position of
this camera, don't be, I repositioned it before leaving!
My project compares mammal diversity in primary (old growth) and secondary (regenerated) forest. With this I hope to assess the effect of human activity and Kichwa forest management on the mammal populations of Payamino. My means of recording mammals are camera traps.

Despite their diversity and abundance in tropical habitats, mammals are hard to happen upon in the rainforest. We are large clumsy alien species, clambering about the forest and scaring things away. Additionally, many animals are nocturnal. So, camera traps are a perfect way to monitor medium to large animals in the field. They are triggered by movement or heat sensors – depending on the model – and usually use infrared flash, so as not to startle the subject.

So far, my camera traps have captured a variety of rodents and opossums, deer, coatis, peccaries, grey-winged trumpeters, curassows and smaller birds, ocelots, a giant ant-eater, and even a jaguar! And that's just in secondary forest. I am looking forward to collecting the first lot of primary forest cameras and see what they reveal!

a) Nine-banded armadillo, Dasypus novemcinctus; b) red brocket deer, Mazama americana; c) nocturnal curassow, Nothocrax urumutum; d) grey-winged trumpeter, Psophia crepitans.

Once I have completed data collection and run some stats, hopefully I will be able to get an idea of the effect of human presence on mammal diversity in Payamino. As secondary and primary forest are visibly different, it's very possible that species composition or abundances (I am looking mainly at composition) differ as well. However, finding a jaguar in secondary forest – albeit in an unfrequented area – came as a nice surprise, so there is also the possibility that there is little variation. This seems plausible as areas of primary and secondary forest are often contiguous, so animal populations in primary forest will refill disturbed forest at some point during it's regeneration, the question is whether all animals will accept this new forest or will some restrict themselves to old growth.

I will leave it there at the risk of making camera-trapping or rainforest conservation management sound boring, but there are more detailed posts about my project methods (and many photos) on my personal blog (tambarikosy.blogspot.com) if you are interested in knowing more.

Jaguar (Panthera onca) in transitional secondary forest, just 3 km from the station!




S.-Xaali O'Reilly Berkeley is a University of Manchester Zoology student on placement as Communications Coordinator (July 2012 - July 2013) of Timburi Cocha Research Station. She writes updates of her life in the rainforest, research, and other bits of biology that take her interest on her personal blog Tambarikosy in Timburi Cocha