Transecting through Vallé Chacabuco

As you drive along the X-83 road through Vallé Chacabuco in Patagonia National Park, you pass many species characteristic of the Patagonian Steppe. There are Calafate bushes, with their tasty blue berries protected by sharp thorns along with Neneo and Neneo Macho, both cushion plants which are much less forgiving than their name implies. Swallows and finches swoop in front of the road, racing the car before turning and disappearing into the mixed scrub off to the side. Yarrow, Bull Thistle, Mata gris and Siete Camsisas line the road adding color during their flowering season. If you’re lucky, you might catch a glimpse of the larger, ostrich-like Ñandu, running about through the plants before disappearing. 

You come up over a hill and look out over a large valley, with a half-dried lake situated in one corner. Clustered around the water is a herd of Guanacos, a member of the Lama species. They are large animals, just slightly smaller and slimmer than a horse, with a long neck and legs, covered in brown fur with a white underbelly. When they run, they look especially funny, the males often chasing each other, trying to nip the other and assert their dominance. Because it is late summer the babies, Chilangos, have grown a bit, but still clearly stick out as the young and follow the adults around, mimicking their actions. The herd can be anywhere from five or six Guanacos to eighty or more, and there is always at least one Guanaco acting as look-out, standing on a nearby ridge or hill, watching for predators while the rest of the herd grazes in peace. They are mostly unfazed by human presence, looking up occasionally, but usually deem that you are not threat and it’s safe to continue eating. 

Over the last month, I spent several days collecting population data on the Guanacos in the Chacabuco Valley. The Round River students all came together to tackle the large task at hand and the valley was divided up into forty transects, the majority of which were off-trail walking transects. Each morning, after breakfast around 8 am, we would all load into the vans and drive out to which ever area we were working. At each stop four people would get out, with one pair heading due North of the road and the other heading due South. Two kilometers later along the road, the next four would hop out. Each pair was responsible for recording all Guanaco sightings within one kilometer east or west of their transect. The transects varied significantly in length from one or two kilometers to sixteen, and we would walk until we couldn’t go any further, whether we encountered a significant change in habitat like a large forest, a large cliff or river that was too dangerous to cross, or reached the pre-determined turn-around time. Along the way, pairs would record any Guanaco sightings, noting the group size, approximate ages and sexes, as well as the direction and distance they were from the observer. 

The transects were beautiful, but not always easy. There were several that went directly through marshes, with students wading past their knees in water, moving amongst tall grasses. Others went through thick patches of scrub, with thorns and branches blocking the way. Some pairs went over tall ridges, with grand views of the valley that were breathtaking. The easier ones followed trails or roads and sometimes felt like a leisurely stroll through the park, watching the wildlife and snacking on Calafate berries. During one transect, a pair of students reached a river, and not wanting to get their pants wet, they crossed in just their underwear and ate lunch on the other side, warming up in the sun. Driving back to basecamp at the end of the day, students shared their stories, detailing rocky scrambles, wildlife sightings, moments of joy and of frustration. Both the good and bad transects were valuable for our research, compiling important information on the Guanaco population in the valley and comparison data from previous years.