Recently, Biokryptos has been working to maintain our project Tepui Watch on the summit of Auyan Tepui. The work has been difficult and we have needed to re-evaluate our survey strategies and replace and service our camera traps. In October 2018, with the assistance of board member Alberto Pomares and lead investigator Arturo Berti, the camera traps were tested on the talus slopes of Auyan at Campo Guayaraca to determine their functionality. This three week long test resulted in startling images of the big cat Puma concolor (aka puma, mountain lion, leon de montana) on the talus slopes of Auyan Tepui at Campo Guayaraca , 1,100 meters asl.
|Puma captured September 22 2018 using a Moultrie 180 camera, Campo Guayaraca 1,100 meters elevation|
Camera Trap Test
Early in 2018 all cameras were removed from the summit and taken into Caracas for inspection and repair by board member Vittorio Assandria. Of the twelve camera traps used by Biokryptos since our pilot study in 2012, eight were functional for the test at Guayaraca. The other four cameras suffered from catastrophic damage due to continual exposure to the harsh tepui environments, where constant precipitation and temperature changes have irreparably damaged the electronics of our traps. Our remaining traps are a mixture of three brands: Reconyx, Moultrie, and Bushnell. The traps were set in pairs at different places in and around Campo Guayaraca, all facing attractant baits. The intention was to test the effectiveness of each camera trap and to compare competing models. The results of this test are still being analyzed by Biokryptos board members to determine which company we will work with in the future to continue Tepui Watch.
In terms of target fauna, our focus was not on conducting an in-depth study at Guayaraca. We are still working to understand the ecological dynamics of the talus ecosystems, which are complex hybrid of lowland and summit vegetational assemblages subject to the effects of global climate change. To examine the talus in totality will take a much larger effort than Biokryptos is prepared to undertake at the moment. It is with some good fortune that we were able to obtain the first photographic confirmation of Puma concolor at Campo Guayaraca. There have been sporadic reports of big cats on the talus and the summit of Auyan Tepui. In 2016 Biokryptos lead investigator Arturo Berti obtained photographic evidence of big cat scratch marks on trees in the north west summit of Auyan Tepui. Reports of "mountain lion" on Auyan were also reported in 1989 by Dr. Armando Michelangeli of Terramar during an expedition to explore the eastern portion of the tepui, as documented in National Geographic magazine (Nat Geo May 1989). This is the first photographic evidence of P. concolor on the talus of Auyan, and supports the validity of the 1989 summit sightings and trace evidence found in 2016.
|Puma captured on a Moultrie D 55, Campo Guayaraca 1,100 meter elevation. This is the first photo taken of a Puma on a tepui talus slope.|
The puma is a widely distributed oblate carnivore spread across North and South America. These cats thrive in a diverse variety of habitats, from deserts and scrub to tropical forests and cold coniferous forests. They are found from sea level to 5,800 meters in the South American Andes. They are IUCN Red Listed Least Concern (LC) due to wide distribution across North and South America, but with a declining population trend. Much of what we know about puma behavior and ecology comes from studies conducted in North America, and studies in Central and South America are lacking. Puma are a protected species in Venezuela, and throughout much of South America. The primary threat to these cats in South America is habitat destruction; the puma population is protected in Canaima National Park and should therefore be considered stable. However, increased economic pressure in Venezuela may be encouraging the indigenous Pemon people to rely increasingly on hunting wild game as a food source. If this is the case, human encroachment on puma habitat may be driving these cats into the highlands to find food.
P. concolor on Auyan Tepui
|Claw marks are present on trees two kilometers west of Angel Falls.|
Markings like these indicate the presence of pumas or other big cats.
The population density of pumas in South America varies from 0.5 to 7 individuals per 100 square kilometers. The variables which dictate population density are ecological richness and abundance of prey species. In North America, carrying capacity has been estimated at 26 to 52 square kilometers per individual, however carrying capacity has not been determined for pumas in the tropics, and certainly not for the semi-isolated tepui ecosystems. With 700 square kilometers of summit area and 200 square kilometers of talus slope, Auyan Tepui is roughly the size of the island of Guam. Assuming the North American carrying capacity metric is correct for all pumas, we could have between approximately 26 to 13 pumas on the summit of Auyan at any given time. The range of individual pumas varies as well, from 32 to approximately 1,000 square kilometers. Range overlap is not well understood, though it seems that male and female ranges tend to overlap. It seems that range is reduced where prey species are abundant and non-migratory, and expanded when prey is scarce or migratory.
While it is tempting to assign numbers of puma on Auyan based on the known population density and ranges of puma in North America, this speculation is premature. First, it should be recognized that individual puma must be able to invade tepuis at will, and do not represent a population restricted to the summit. The tepuis may act as biogeographic islands for some organisms, but not for a large bodied apex predator such as a puma. No population of big cats can exist in such restricted isolation. Instead, future research should focus on what is enticing pumas to the tepuis.
|Deer recorded at Guayaraca several days after puma were photographed.|
In terms of feeding strategies, the puma is a generalist and food sources vary from insects to large ungulates. In the tropics, studies have shown that pumas rely on smaller bodied mammals with jaguars taking larger bodied mammals such as tapirs and cattle. This adaptability places pumas in roughly the same trophic category as the other mesopredators found on Auyan Tepui; generalist capable of existing on a variety of food sources and adaptable to an ecologically complex and topographically discontinuous environment. On the talus slopes, Biokryptos camera traps also recorded Guiana deer; both single individuals and a pair, in close temporal proximity to the records of the puma. As deer species are a preferred food source of puma across North and South America, it seems likely that the puma we photographed was hunting these animals. While we have yet to find any evidence of deer on the summit of Auyan, based on the feeding strategy of P. concolor there seem to be sufficient food sources on the summit to support a big cat.
|There are two deer in this photo- one in the foreground and a second deer immediately behind partially obscured by brush. The photo was taken at Campo Guayaraca. The time stamp is inaccurate.|
Auyan may have other features which make it an attractive place for pumas to invade. The 1989 sighting involved a female puma and three cubs near a rocky cave; it is possible that female puma are enticed to the summit to find dens to raise cubs. The lack of other predators on the summit and abundance of small prey may make the tepui summit an attractive place to reproduce, where caves and suitable dens are ubiquitous. The problem with this hypothesis is that female puma increase their caloric intake after cubs are born, and make more frequent kills. Without large prey species to feed on, female summit pumas would have to expand their range to feed their cubs.
A more alarming enticement could be upward migrate caused by global climate change. As lowland climate envelopes are pushed toward the poles and higher elevations, puma may be entering Auyan as the summit climate envelope becomes more suitable to their preferred prey species. This form of vertical displacement has been observed across the planet, as lowland species move to higher elevations in response to changing environmental pressure. This phenomena is predicted to have disastrous results for endemic tepui summit flora, where extinction rates of up to 80% are expected for vascular plants by the year 2100 A.D. Recent reports from the I.P.C.C. indicate that the rate of global climate change is increasing faster than anticipated, and the previous models for tepui summit extinctions may need to be revised to incorporate this new reality. While global climate change will mean a tremendous biodiversity loss for the tepuis, the effect on puma populations is unknown. P. concolor may be adaptable enough to survive massive changes in the composition of lowland tropical grasslands and forests by migrating to the highlands and establishing a population at higher elevations.
Biokryptos has demonstrated that the puma P. concolor is present at 1000 meters in the forested talus slopes of Auyan Tepui at Campo Guayaraca. While sightings and trace evidence exist indicating that puma are also present on the summit, direct photographic evidence does not yet exist. The population and trophic strategy of tepui summit pumas is unknown, and requires further study. Based on the available data, we surmise that tepui summit puma populations must be able to emigrate from the summit back to the lowlands, as it is doubtful that Auyan Tepui maintains a summit ecosystem with the carrying capacity to support an isolated puma population. The impact that puma have on endemic summit fauna is completely unknown, and requires further study. As far as what is enticing puma into the summit, factors such as increased habitat loss in the lowlands or competition with humans may be a factor, along with global climate change. It is also possible that puma historically invade tepui summits, and that this behavior has gone unnoticed due to survey and research gaps. What is needed is an expansion of camera trap and surveillance efforts on all the tepui to monitor faunal composition and the effects of climate change. The use of new technologies and environmental DNA analysis can help streamline this process, but a larger effort is needed now to conserve and survey tepui biodiversity.