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You’ll Never Guess How Biologists Lure Jaguars To Camera Traps

The views expressed are those of the author and are not necessarily those of Scientific American.


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Field biologists are increasingly turning to camera traps to collect data. The set-up is really simple: when an animal passes in front of a camera, an infrared sensor becomes activated, and the camera silently snaps a photo. Sometimes – especially for camera traps designed to detect nocturnal species – an infrared flash, invisible to most mammals and birds, is used.

The photographs generated from camera traps can then provide researchers with far more data than they would be able to collect themselves with more traditional field observations. Often, this allows them to generate photographic evidence of a species’ natural behaviors without the confounding effects of direct human observation. It allows them to collect data continuously, throughout the day and night. And a camera trap can help researchers collect evidence of rare species or rare behaviors, as was demonstrated last week when a camera trap captured a golden eagle preying upon a sika deer. Or they could help researchers come face-to-face with an animal that might otherwise be dangerous or harmful. An array of camera traps is also more cost efficient than paying an army of field assistants to observe animal behavio or to conduct a census.

Camera traps are also far less invasive than most other forms of wildlife data collection, since critters don’t need to be trapped and released. And their presence is far less stressful for most animals compared with human observation.

Take the jaguar. The third largest cat in the world after tigers and lions, jaguars (Panthera onca) are nocturnal, solitary cats. Females’ territories can range from twenty-five to forty square kilometers, and males can roam areas twice as large. Due to primarily to habitat loss and to conflict with farmers, jaguar populations are declining; they’re considered “near threatened” by the IUCN. Oh, and a mature jaguar’s jaws are capable of biting down with two thousand pounds of force, the strongest of any cat. It subdues its prey in an ambush attack by biting down on the skull, its massive teeth puncturing the brain adjacent to each ear.

Put together, this makes jaguars well suited for for camera trap research. Still, human observers can do things like change the direction they’re looking. Cameras generally can’t. So biologists like Miguel Ordeñana try to hedge their bets and optimize the probability that an animal of interest will come by and trigger the camera’s shutter.

Ordeñana is a biologist with the Natural History Museum of Los Angeles. He’s an expert on camera traps, and when he’s not using them to understand the mountain lions who make their homes in the mountains of Los Angeles, he conducts field research on jaguars in Nicaragua.

Meow.

And the best way to convince a jaguar to trigger a camera trap? Calvin Klein Obsession for Men. Seriously.

According to Ordeñana, a Bronx Zoo researcher once tried a bunch of different scents and discovered that jaguars really liked the Calvin Klein cologne. A researcher might spray some of the cologne on a tree branch that sits within the camera’s field of view.

What’s so special about this particular scent mixture? “It has civetone and it has vanilla extract,” he says. Civetone is a chemical compound derived from the scent glands of civets, smallish nocturnal cat-like critters native to the Asian and African tropics, and it’s one of the world’s oldest perfume ingredients. “What we think is that the civetone resembles some sort of territorial marking to the jaguar, and so it responds by rubbing its own scent on it,” he explained to me. And the vanilla might set off the cats’ curiosity response. No matter which compound is responsible for jaguars’ interest – or both – the key is that the scent gets them to stick around long enough to activate the camera’s shutter.

The molecular formula for civetone is C17-H30-O

I asked Miguel if he avoids wearing Calvin Klein Obsession for Men while doing field work in Nicaragua. “I don’t really care, because the chances of me running into a jaguar are so slim.” Which, after all, is why he uses the camera traps in the first place.

Still, you probably wouldn’t want to wear the cologne and then take a nap, alone, at night, in the jungle. Then again, you probably wouldn’t want to do that anyway.

A jaguar captured by one of Miguel Ordenana's camera traps on January 7, 2013. Click photos to enlarge.

Images: Header image via Bjørn Christian Tørrissen/Wikimedia Commons. Camera trap photos via Paso Pacifico, used with permission.

Update: It’s worth pointing out that most modern perfume makers use synthetic versions of civetone, extracted from palm oil, so that they don’t have to harass actual civets…

Jason G. Goldman About the Author: Dr. Jason G. Goldman received his Ph.D. in Developmental Psychology at the University of Southern California, where he studied the evolutionary and developmental origins of the mind in humans and non-human animals. Jason is also an editor at ScienceSeeker and Editor of Open Lab 2010. He lives in Los Angeles, CA. Follow on . Follow on Twitter @jgold85.

The views expressed are those of the author and are not necessarily those of Scientific American.





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  1. 1. Sean McCann 3:00 pm 10/10/2013

    I tried this at the Nouragues reserve in French Guiana…Bought a bottle especially for this purpose! It did not work that time, but I suspect if I had a different camera trap setup it might have.
    BTW, this perfume is pretty gross, and very persistent!

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  2. 2. jplatt 3:23 pm 10/10/2013

    This is interesting. I know scent lures have been used for hair traps as well: http://www.adfg.alaska.gov/index.cfm?adfg=wildlifenews.view_article&articles_id=595

    It does make me wonder… The use of lures would be considered unethical by many wildlife photographers. Many others will use whatever it takes to get the shot. Is there any scientific debate about the ethics of this technique?

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  3. 3. Jason G. Goldman in reply to Jason G. Goldman 3:33 pm 10/10/2013

    Interesting question, John. Being an amateur wildlife photographer myself, I wonder if the aversion to using lures is more about photographic ethics and less about wildlife ethics. I’ll ask Miguel next time I talk to him. Personally, I can’t see a scientific reason that using scent lures like this would be unethical.

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  4. 4. CS Shelton 9:32 pm 10/10/2013

    Civets aren’t really cats per se, are they? No more than hyenas are.

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  5. 5. scilo 11:27 pm 10/10/2013

    I see no ethics issue either. No harm is done, and the animal is doing nothing unnatural. However, my rubs with the wilds yields strange observations that I do not believe would make good still camera fodder. Such as eagle eats dear. So my Q. is this: What do you expect to see other than the fact that a cat is there? Seasonal cues no doubt. But interaction with own, and other, species would still require a skilled observer.
    Other than that, the pics are great. A what a blessed journey you are on. Thank you for sharing.

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  6. 6. Jerzy v. 3.0. 5:31 am 10/11/2013

    I wonder if there is any less expensive perfume with the same compounds?

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  7. 7. Jason G. Goldman in reply to Jason G. Goldman 11:53 pm 10/11/2013

    Indeed, they’re not cats, taxonomically. They’re… cat-like. Thanks for catching that. Fixed.

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  8. 8. lynnoc 2:37 am 10/12/2013

    Jason I love your reports. I can’t imagine any “Committee for the Protection of Human Subjects” having an objection –well maybe that’s not entirely true, some have gotten really obsessive and over the top. But this seems like an entirely ethical way to allow us to learn more about what’s out there without disturbing wild animal life, and further, about their specific behaviors. Every week we read more about various animals’ behaviors that are “just like ours.” This week it was elephants learning to point (and Bonobos do the equivalent leaving markers for those following on a trail, by way of bending twigs in the right direction). Great story and great pictures.

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  9. 9. Adrian Morgan 6:24 am 10/13/2013

    Re update: so instead of harrassing civets, they harrass orang-utans instead, right…?

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