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GVI.2014.2 

November Monthly Achievement report, Jalova

A colourful riddle on Eyelash Palm Pitvipers 

ObjectiveIn line with GVI’s  objectives, Empowerment is one that aims to equip our alumni with theknowledge and ability to further contribute towards key global and local issues. Jalova baseseeks to equip our volunteers, staff and interns with the skills, knowledge, abilities and en-thusiasm to continue making a difference into the future.

We also seek to contribute with National and International conservation efforts and providedata to help respond many Scientific questions that are yet to be answered.

Summary

Raphael Coleman is a Zoology student from the University of Manchester. His degree in-cludes a year of industrial or professional experience; so instead of spending months in alab, he chose to get back in touch with GVI, as he had volunteered with us twice before inSouth Africa and Fiji, and thought this was the best way to get more hands on experience inthe field.

While on his placement, he has to design and carry out a research project, which is thenevaluated by experts on his chosen topic from his university. It could be quite tricky to designa study which conforms to the regulations of the National Park we work in, and operatesunder the methodology of our current permits, but he finally he decided on analysing a spe-cies we normally see in the forest surveys and gather data to help answer the question onthe different colours the Eyelash Palm-Pitvipers present.

Report-Raphael ’s test imonial

When I first arrived Megan Brett, the forest biodi-versity project leader, mentioned to us in trainingthe variety of different colour morphs there are ofthis species, and how it might be interesting tostudy them. At Jalova alone, pitvipers come in agreat range of colours, from several differentshades of green to gray, white, peach, light blue

and the famous yellow morph, locally known as“oropel” or “gold-skin”, which is found only in andaround Costa Rica. Other locations have recordsand photos of different colourations, such as red,pink or brown. On top of this, each snake canhave an almost unique combination of differentcolours in spots or bands on its sides, and mott-led along its back.

 As a student of animals, my curiosity was piqued.I can’t  resist asking, why are there so many dif-ferent possibilities within this one species? Inmost cases a single colour, usually some simple

gray, brown or green which blends in with the background, turns out to be the best strategy

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GVI.2014.2 

and all the others are eliminated by natural selection. What mechanism keeps the colourmorphs in the gene pool? Why are the morphs so numerous at Jalova, when other locationshave rarely recorded more than two or three colours at once? Why are different coloursfound in different places?

Biologists and wildlife enthusiasts have put forward a number of potential explanations, sup-ported mostly by anecdotes or photos, as to why a single species of viper displays such va-riety in colour. Some suggest the vipers use their colours for camouflage in differing envi-ronments, with bright green snakes lying hidden on moss-covered leaves while yellow onesmight perch unseen among palm fruits. Others pertain they might even use the colours oftheir whole bodies to attract prey, much as juveniles do with their brightly coloured tail tips,wriggling them like worms to attract frogs or lizards closer to their jaws. In this way, a yellowsnake positioning itself among heliconia flowers could look enough like the bananas thatgrow on these plants to attract an unfortunate bat or mouse opossum. Another theory positsthe colours help to confuse both predators and prey, as they can’t  have a single templateimage in their minds of what a viper looks like, and they find it difficult to learn to recogniseall the different morphs.

Whatever the reason, we don’t yet know for sure - the adap-tive significance of the colourmorphs remains unstudied. Soto find out, I’ve been research-ing study techniques, design-ing survey protocols, and mak-ing a training presentation.We’ll be collecting data on thevipers’  colours and those ofthe substrates they are lying

on waiting in ambush, buildingup a photographic databasewhich can be analysed back atthe biological station. Analys-ing how much snake and sub-strate colours match will allowus determine to whether thevipers rely on camouflage for prey capture or anti-predator tactics. We’ll  also be recordingdata on the vipers’  prey and predators, along with other ecological factors such as habitattype and weather conditions. This will help us to determine whether the vipers’  choice ofperch or ambush site depends more on external factors than on their own colouration.

In the new year, we will hopefully be sending out volunteers, interns and staff members withfresh new training to gather data on the vipers and solve this colourful riddle. Of course, no-body will touch them and it will be done following high health and safety protocols to keepeveryone safe.

Raphael Colleman, Volunteer field staff