- Since 1990, the use of hair traps has been rapidly expanding in wildlife biology, but mainly in cooler climates.
- By collecting hair samples, scientists can non-invasively collect DNA samples of wild animal populations to learn about genetic diversity and determine their habitat ranges.
- Three past studies successfully used hair traps in the tropics. Two monitored several species of carnivores in Mexico, and one, as yet unpublished, monitored dingoes in Australia.
It is difficult to protect endangered species without understanding how many individuals exist or where they’re located. However, learning this can be a daunting task when the species in question are rare and elusive carnivores — and all the more so when they live in areas that make tracking them difficult.
The tropics is one such area. There, carnivores tend to be sparse and conditions humid, which make genetic samples like scat decay quickly. In a study recently published in Mongabay’s open-access journal Tropical Conservation Science, researchers investigated deploying scented hair-traps to gather population data in Peninsular Malaysia, home to 28 species of terrestrial carnivores, many with dwindling numbers.
Since 1990, the use of hair traps has been rapidly expanding in wildlife biology, but mainly in cooler climates. Researchers set a trap that will collect hair from a wild animal if they touch or rub against it. Often appealing odors, like fatty acid or men’s cologne, lure the animals to the traps. By collecting hair samples, scientists can non-invasively collect DNA samples of wild animal populations. Using these samples, they can learn about the genetic diversity within animal populations and determine their habitat ranges.
Three past studies successfully used hair traps in the tropics. Two monitored several species of carnivores in Mexico, and one, as yet unpublished, monitored dingoes in Australia. For the present study, a team led by Laurie Hedges, a researcher with the Malaysian research group Rimba, wanted to see if hair traps could help reveal the genetic diversity of Peninsular Malaysia’s elusive carnivores.
Hedges and his team set hair traps in two main wildlife corridors in Malaysia: 23 traps in the state of Perak and 12 in the state of Terengganu. Some traps they placed on the ground, where canids might be likely to investigate, but most they attached to trees, where felids would be likely to notice them and, hopefully, rub against them leaving behind some hair.
They deployed the traps and monitored them via motion-triggered cameras for a total of 764 nights. Over the course of the study, the team detected 18 carnivores near the traps via the cameras. However, only one — a male Malayan tiger (Panthera tigris jacksoni) — actually rubbed against a trap and left a hair sample. Another—a male clouded leopard (Neofelis nebulosa)—rubbed the spot where elephants had previously removed a scented hair trap.
“Our preliminary results indicate some potential for scent-baited hair traps to obtain hair samples of large carnivore species,” the authors write, adding “However, it remains to be seen whether they can serve as effective monitoring tools for carnivores, especially in landscapes such as Peninsular Malaysia where elephants pose a serious obstacle to the function of these traps.”
The researchers noted several factors that could improve results in a future study, including making the scents stronger or changing them altogether, or possibly changing the appearance or the location of the traps themselves. “More systematic survey designs are needed to assess the full potential of this technique for non-invasive monitoring of carnivores in Peninsular Malaysia,” they conclude.
Hedges, L., Morrant, D.S., Campos-Arceiz, A., Clements, G.R. (2015). Feasibility of using scent-baited hair traps to monitor carnivore populations in Peninsular Malaysia. Tropical Conservation Science 8(4): 975-982.