Investigating Ecotourism impacts on mammal activity in a Costa Rican protected area

Costa Rica belongs to one of the 36 world biodiversity hotspots,
representing one of the most important ecotourism destinations
in the world and providing huge socio-economic and
environmental benefits. However, tourism may have an impact
on biodiversity which should be investigated thoroughly, giving
priority to poorly studied areas. The Karen Mogensen Wildlife
Refuge (KMWR) is part of the Biological Corridor of the Nicoya
peninsula (NW Costa Rica), among the least studied regions
of the country in terms of mammalian fauna. In the past, this
area underwent significant human-alterations, but most habitats
were restored thanks to the establishment in 1996 of a private
protected area, owned by ASEPALECO association. Inside
the KMWR, ecotourism and the establishment of an eco-lodge
represent a fundamental income for the economic sustainability
of the protected area. Through a camera trapping survey, we
investigated the mammal community of the KMWR and we
assessed the influence of tourists on their diel activity patterns.
The survey was carried out from mid-January to mid-April 2019
using six camera traps placed close to the paths and sources of
water, with the aim to improve animal detectability. A species
accumulation curve was built to assess if our survey effort was
sufficient to describe the community. To assess if mammal
community was disturbed by human presence, we tested if the
presence of tourists changed the diel activity patterns of i) the
most common species (>50 detections), ii) the entire community,
iii) nocturnal vs. diurnal species, and iv) strictly terrestrial
vs. predominantly or semi-arboreal species. We described the
diel patterns with a probability density function (Kernel Density
Estimate), and we calculated the coefficient of overlap i to
compare the activity variation in relation to tourists’ presence/
absence; we tested the statistical significance of the difference
through theWatson’s two-sample test. Tourist presence/absence
data were provided by ASEPALECO, which records all the
entrances in the protected area.
In 537 trap-days we recorded 467 independent detections of 12
mammals: Odocoileus virginianus, Dicotyles tajacu, Puma concolor,
Leopardus pardalis, Conepatus semistriatus, Eira barbara,
Nasua narica, Didelphis marsupialis, Tamandua mexicana,
Cebus imitator, Cuniculus paca, Dasyprocta punctata. The
accumulation curve indicated that we reached a plateau after 219
trap-days, i.e., no new mammals recorded after this period. During
the sampling, tourists were present for 52 days, and absent
for 50 days, with little difference in the number of camera-trap
detections (239 and 228, respectively). The presence/absence of
tourists did not produce any significant change (e.g., i>0.77) in
the temporal activity patterns all species and groups considered.
Our results showed that the number of large mammals in the
KMWR is comparable to that recorded in other protected area
of Costa Rica, including some rare and elusive species; this
suggests that habitat restoration was effective for mammal conservation.
Interestingly, during our survey, we documented the
first reproductive event of the top-predator Puma concolor in the
area, an encouraging indication of the recovery of the food-web,
after years of protection. There is a large literature documenting
the impact of tourism on wildlife activity patterns, showing
an increase of nocturnality. However, our results showed little
effects of tourists on the activity patterns of species and groups.
This suggests that present tourism management in the KMWR
is compatible with mammal conservation and provides a nice
example of sustainable touristic exploitation.