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The Expert

Miguel RICO has been a principle investigator on Earthwatch’s Pantanal otter project for the past three years. He is passionate about the study and says: “There is no better life than this – working with otters on the Rio Negro river. The otters are almost like family. Every day, I look for them. I can recognise about 46 individuals now, and watching them is a real delight.”

The location

the pantanal, brazil, is a vast wilderness area known for its abundant, diverse and visible wildlife. The flat, open landscape consists of a range of tropical forest and savanna habitats, a complex river network and the largest expanse of tropical wetland in the world. The region has supported cattle ranching BRAZIL for over 200 THE PANTANAL years and has São Paulo become a popular wildlife-watching destination.

ANIMAL BEHAVIOUR

How hard can it be to find a GIANT? They’re large and they hunt in packs, so giant otters ought to be easy to study. BBC Wildlife editor SOPHIE STAFFORD put her tracking skills to the test with a research team in Brazil’s Pantanal.

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BBC Wildlife

provide policy-makers with information about the biology of the Pantanal’s otters, which will enable them to formulate appropriate, scientifically founded regulations for local ecotourism. First, though, they need to get to know the local otters intimately.

MESSING ABOUT ON THE RIVER As otters spend most of their time in the water, the majority of the research is conducted from canoes and motorised boats. In a canoe, the researchers can locate, approach and watch the otters without disturbing them. The Rio Negro is a broad and seemingly sluggish river, but as we volunteers soon found out, the water has a powerful current that makes itself known when you’re paddling back upstream after a long day on the river, and when your canoe refuses to go in the direction you intend. Dense forest crowds the banks, and every meander is edged by a small beach, studded with basking Jacaré caimans. There are apparently 30 million of these small crocs living in the Pantanal, and they proved to be our constant companions while on the June 2006

river – and sometimes when nowhere near it (during the dry season, they walk for miles across land in search of a new territory, so you often stumble across them in unexpected places). And somehow there always seem to be caimans sunbathing exactly where you need to beach your canoe. It was time to put one of Ellen Wang’s convictions to the test. “The caimans are more scared of you than you are of them,” Ellen said breezily. “They won’t bother you at all. Just don’t grab them by the tail.” As if! So one morning, soon after my arrival, I decide to tiptoe up on a recumbent reptile to see just how close I could get before his nerve gave out. He was brave – maybe because he had back-up in the form of 13 pairs of eyes watching me suspiciously from the safety of the water. I got to within about 10 paces before he lunged off the bank with a splash. Score one to Ellen Wang. After that, beaching the canoe was less a battle of nerve and more a matter of trying to avoid hitting the lazier caimans with the prow. Every day, Helen, Miguel and research assistant Manoel canoe up and down the Rio June 2006

Negro in search of their study species. The neotropical otters are rarely difficult to spot. Before we’ve even pushed our canoes off the beach, we can see them among the knotty

Neotropical otters eat noisily, with much smacking of lips, snapping of tiny sharp teeth and cracking of bones. roots of the bankside trees and hear their enthusiastic crunching of tiny fish. For such small animals, they eat incredibly noisily, with much smacking of lips, snapping of tiny sharp teeth and cracking of bones. Whipping out our clipboards and GPS (Global Positioning System), we note what each animal is doing at one minute intervals, twisting and turning in our seats to keep them in view as our canoes drift unhelpfully in circles downstream. The otters appear unafraid

of us, often diving and surfacing right by the prow of the boat with an inquisitive ‘huff’ before vanishing beneath the surface again. The giant otters are another matter. Despite their large size (about the same as a German shepherd dog), and their habit of travelling in groups, giants can be surprisingly hard to find. So the researchers often have to content themselves with merely spotting signs of their presence. From the boats, they scour the banks for denning sites, footprints, resting places, ‘campsites’ and spraints (scats). The giants modify areas of riverbank they use regularly by removing dry leaves and impeding the sprouting of new vegetation – tell-tale signs for keen-eyed researchers who are also on the lookout for active dens, which can be identified by fresh yellow sand cascading down the banks. Giants also like to rest up for long periods in campsites, which they clear of vegetation and mark in an unusual way – by squirting lots of watery faeces all over the area and then using their forepaws in a strange, circular, waddling motion to mix them in with the soil and sand. BBC Wildlife

Kevin Schafer/NHPA

a 26km stretch of the Rio Negro, a tributary “THERE’S NOTHING TO FEAR in the of the Paraguay River. With the assistance Pantanal,” announced field co-ordinator Ellen of teams of Earthwatch volunteers, the Wang at our orientation meeting. “Apart from researchers are building a complete picture the peccaries, which will bite you given half a of the otters’ natural history. Their aim is to chance (so make sure your tree-climbing develop management plans for both species, abilities are up to scratch), the piranhas and taking account of the pressure of human stingrays lurking in the cold, deep waters of activities in the Pantanal, and evaluate the the river (so shuffle, don’t walk), the pit vipers potential impact of increasing that may climb into your boots if you ecotourism in the area. leave them outside (so don’t), and two did you know? “The giants are a great species of blood-sucking bat, which Earthwatch supports attraction for tourists,” explains don’t normally bite humans.” more than 280 Miguel. “They are active during With these words of encouragement, scientists in 137 field research projects in the day and very sociable, I arrived in Brazil’s Pantanal, the 50 countries. Each moving around in large groups world’s largest wetland and home to year, about 3,500 of up to 20 individuals (though the greatest concentration of – mainly volunteers take part groups average about five benign – wildlife in South America. in these projects and their efforts really individuals around here). They I was joining a research project, run make a difference. are also incredibly playful and by environmental charity Earthwatch, inquisitive, so they often actively studying the ecology of the giant otter approach tourist boats.” But studies have Pteronura brasiliensis and its smaller cousin, shown that the otters are sensitive to human the neotropical river otter Lontra longicaudis. disturbance, including poorly managed For the past four years, researchers Miguel ecotourism, which can affect their reproductive Rico and Helen Waldemarin have been success. The researchers, therefore, aim to studying the giant otter families that live along

Both Pantanal otter species – the neotropical river otter and giant otter seen here – have great ecotourism potential, since they are attractive, playful animals. You just have to find them first.

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ANIMAL BEHAVIOUR  GIANT OTTERS

GO WILD IN THE PANTANAL

A DAY IN THE LIFE of an otter researcher

One man’s dedication to field research

Pete Oxford/naturepl.com

Factsheet

N OW YOU D O I T

DIET ANALYSIS The researchers regularly collect otter spraints (scats), note the GPS location, label them and preserve them in plastic bags. Here, Miguel scrapes a giant otter spraint into a bag.

NEOTROPICAL RIVER OTTERS are active during the day in most places where they are not disturbed by humans. They are playful and confiding, and will approach the canoe if you sit quietly.

JACARÉ CAIMANS are not as fierce as they look and are great companions on the river. They are extremely courteous, move out of the way if you get too close and don’t mind posing for photo shoots.

No one is entirely sure why they do this, but it is thought that it serves to fix their smell in the soil as a territorial marker. So dedicated are the Earthwatch scientists that spotting one of these giant spraints is a source of great delight. With a nimbleness born of months in a canoe, Miguel leaps from the vessel onto the bank and, armed only with a plastic bag and a pen, goes in to collect the smelly mess (see box above). Every spraint, whether it is on land or tree, fresh and fragrant or old and dry, receives the same treatment, and is lovingly recorded and scraped into a polythene bag to be taken back to the research station for analysis.

creeks, where their large fish prey is easier to catch, due to the shallow water and closed environment. The neotropicals, by contrast, are more likely to be found hunting in the deeper margins of the main river. Exploring the oxbows is challenging – not only do the canoes have to be carried for short distances, but sometimes you have no choice

SOMEONE’S GOT TO DO IT

but to get out and walk. After Ellen Wang’s words of caution, I was surprised (to say the least) to find myself wading knee-deep in the Rio Negro’s caiman- and piranha-infested waters, with mud and who-knows-what-else squelching between my toes. Miguel did offer to carry me, but then I would have been deprived of the experience of having my feet nibbled by small fish. As I watched bemused, a brigade of misguided cleaner fish (lambari) sucked enthusiastically at my toes. “They usually clean the ticks off the capybaras’ legs,” explained Miguel, hiding a smile. “So perhaps they mistake the moles on your feet for ticks.”

Over the next two weeks, signs of the giants’ presence were abundant (and other people saw them), but to me the animals themselves remained elusive. As we sat patiently watching an empty river for several hours, it struck me that to be an otter researcher you need special skills. You must be able to distinguish at a glance between a swimming otter and an emergent branch, caiman snout or leaping fish – not as easy as it sounds. You should also be able to spot, from a moving boat, an otter spraint 8m away on a bank, under a tangle of undergrowth. You cannot flinch at handling faeces and other unattractive substances, and you must have a blissful disregard for tick bites, bee stings and other irritants. (One of the teams accidentally beached their canoe on a bee’s nest with predictable results. Ellen Wang never mentioned that potential bio-hazard!) You have to be strong enough to paddle 15km a day and still have the energy to carry your canoe overland to explore oxbow lakes. Plus you need the patience and dedication of a saint – after two weeks of searching, I never did see a giant.

So why the faecal fanaticism? The researchers are trying to determine whether neotropical otters compete with the giants for food. So far, their research suggests that, though both species are primarily piscivorous, giant otters feed on bigger fish than neotropicals. While the giants favour large catfish and perch, the neotropicals feed mainly on small fish. This difference in diet may also explain why the two otter species are rarely found in the same part of the river. The scientists believe that the ever-elusive giants hide out in the Rio Negro’s many landlocked oxbow lakes and 38

BBC Wildlife

So dedicated are the scientists that spotting a giant otter spraint is a source of great delight.

Sophie Stafford has been editor of BBC Wildlife for the past two years. She has travelled extensively in search of close encounters with wildlife, but this was her first visit to Brazil. She hopes to return soon.

June 2006

WHERE TO STAY: RECANTO BARRA MANSA This lodge on the Rio Negro combines cattle ranching with a well developed ecotourism project. www.hotelbarramansa.com.br/ FAZENDA RIO NEGRO Also on the Rio Negro, this 7,700 hectare cattle farm is owned by Conservation International. Today, it is a model for successfully combining conservation and ecotourism. www.fazendarionegro.com.br BARRANCO ALTO ECO-LODGE A friendly and comfortable farm with excellent wildlife sightings. www.fazendabarrancoalto.com.br POUSADA MANGABAL A working cattle ranch in an area known for its great wildlife. www.pousada.com.br; www.mangabal.com.br REFUGIO ECOLOGICO CAIMAN Home to a pioneering ecotourism project and headquarters of the Blue Macaw (Conservation) Project. www.caiman.com.br

THE PANTANAL is a relatively pristine wilderness, but recent developments threaten its future. Pesticide runoff from intensive agriculture damages the watershed, gold mining has polluted parts of the region with mercury, ‘modernised’ ranches are deforested and planted with exotic pastures, and hunting has reduced some wildlife populations, including caimans and jaguars. Probably the biggest future threat to the Pantanal is a massive modification (channelisation) of the Paraguay and Paraná rivers being planned to speed shipping and generate electricity. A major gas pipeline from Bolivia could also disturb the most intact region in the north-west by disrupting water flow and increasing pollution and hunting.

BARRA MANSA on the Rio Negro is where the Earthwatch otter project was based during Sophie’s visit.

FRUITS & FRUGIVORES

Researchers investigate how the Pantanal forest survives. AROUND 12,000 YEARS AGO, North and South America were home to many large mammals, including elephant-sized sloths, camels, bison and mammoths. Humans hunted most of this megafauna to extinction. But many fruit trees relied on these species to disperse their seeds, so their fruits were specially adapted to attract mammals, being large and heavy, smelly and green, yellow or orange in colour (colours that mammals can see well). Fruits that rely on dispersal by birds are small and red, black or bicoloured. Nowadays, some fruit trees have very few seed dispersers and must rely on the efforts of smaller mammals, including tapirs and agoutis, and birds such as rheas. In the past century, new seed dispersers have been introduced in the form of cattle, June 2006

horses and feral pigs. Scientists Camila Donatti and Mauro Galetti are trying to find out how the fruiting trees have survived without their preferred seed dispersers, and to identify the role that new dispersers play. Could introduced domestic animals help to maintain this fragile ecosystem? More research is needed to know for sure, but anecdotal evidence suggests that they do. IN THE COURSE of their research, the team has made some interesting discoveries. For instance, the manduvi is one of the tallest trees in the Pantanal and often bears large holes in its trunk, which make it the most important nesting site in the region for the rare hyacinth macaw. Manduvis produce ripe

Camila Donatti

THE SPRAINT SAMPLES are washed through a fine mesh sieve. The remaining fragments are dried and separated into food categories – scales, bones, hair, feathers and shells. They are identified at a museum.

All photos by Sophie Stafford

OTTER ACTIVITY is monitored from canoes and carefully chosen locations on land. The researchers look out for active otters as well as their dens, footprints, resting sites, tracks and spraints.

FLIGHTS BA flies daily from Heathrow to São Paulo; www.ba.com. TAM Brazilian Airways operates three flights a day from São Paulo to Campo Grande; www.tam.com.br

THE pantanal covers 110,000km2. Some areas are flooded permanently, while others are under water from December to June.

CON S ER VAT I ON

Staffan Widstrand

FOCAL OBSERVATIONS Miguel is highly skilled at detecting an otter whisker or a ripple in the water at a distance. The team has so far identified 46 giant otters from 11 family groups using throat markings.

GET INVOLVED IN CONSERVATION Sophie joined two projects with Earthwatch in the Pantanal of Mato Grosso do Sul, Brazil. These were Ecology and Conservation of the Pantanal’s Otters and Keystone Fruits and Frugivores Projects (see below). A number of other projects operate throughout the year under the Conserving the Pantanal Initiative, including the study of peccaries, bats and small mammals. For details % 01865 318838; www.earthwatch.org

A selection of fruit found in December. The team identified 522 trees of 65 species – 83 per cent are dispersed by mammals, birds, fish and tortoises.

fruit from July to September, and though many birds flock to this bounty, only the toco toucan is an effective seed disperser. This is because it swallows the fruit whole, digests the oily covering and regurgitates the seeds clean

and undamaged. This means that, if a healthy population of manduvis – and hyacinth macaws – is to be maintained to preserve the integrity of the Pantanal ecosystem, a healthy population of toco toucans is essential. BBC Wildlife

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BBC Wildlife Brazil Feature