In a new study at the University of Arizona, researchers used body-mounted cameras to evaluate the efficiency of two insect pest sampling techniques—a sweepnet and a vacuum—in a cotton field. The perspective offered new insights into how such methods can be evaluated and could help growers and integrated pest management professionals further fine-tune their sampling techniques. (Photo credit: James Hagler, Ph.D.)

By Edward Ricciuti

Police wear them. Sky divers and surfers wear them. Scientists use them to observe animal behavior. Now, researchers at the United States Department of Agriculture (USDA) are using body-mounted cameras—bodycams—to observe and evaluate how other researchers perform in the field. Specifically, investigators have tested the devices as a way of observing the behavior of people sampling insects and other arthropods in an experimental agricultural setting and then comparing the efficiency of the different techniques used.

Ed Ricciuti

In this case, the setting was an experimental University of Arizona cotton field in Maricopa, Arizona. Published in April in the Journal of Insect Science, the study focuses on the effectiveness of two tried-and-true devices favored for collecting arthropods from cotton and other agricultural crops. One is the old-fashioned sweepnet, a canvas bag on a long wooden handle. The other is a gas-powered vacuum device, which resembles a backpack-mounted leaf blower except that it works in reverse. Each was used by a two-person team, one of whom collected while the other bagged the catch. The sampler wore the camera on the forehead, the bagger on the chest, while working in six plots, each 12.2 meters long with six rows of cotton.

The researchers found that bodycams were an excellent tool for testing the sampling efficiency of each technique. Choosing the right sampling tool from the many that exist depends on many factors, including the type of arthropod and whether it lives in the ground or in foliage, its shape and life stage, the type of vegetation sampled, and even the size of the area involved.

By reviewing video after the experiments took place, the USDA researchers were able to explain seeming errors or unexpected research results. They were puzzled, for instance, why the team using the lightweight net took twice as long to walk between cotton plots than the pair lugging the vacuum (which, at 18.5 kilograms, is 30 times heavier than the net). When they examined the video, they discovered that it had to do with human behavior. The camera footage showed the net team stopping to shoot the breeze while walking between plots. The pair with the vacuum attended strictly to business, moving steadily from plot to plot. The difference was not a matter of work ethic but because the vacuum team had plugged their ears to dampen the noise of the backpack motor and thus were unmotivated to stop and gab.

“Ultimately,” wrote the authors of the paper, “this chatting behavior did not hamper the sweepnet sampling efficiency, but it slowed the overall sampling process for a few minutes.”

The study revealed that each technique had advantages and disadvantages when the performance of the devices was taken into account. Overall, collecting with the sweepnet was more efficient on large plots while the vacuum was best for small patches. Analysis of the video showed it took five times longer to sample a row of cotton maneuvering the cumbersome vacuum than by swishing the net. On the other hand, one single suction—by placing the intake manifold of the vacuum over the plant—generally caught more insects that a single sweep of the net. Far fewer suctions than sweeps come up empty. For small plots, the vacuum was more precise because of its larger catch. For long rows, the net was more efficient because it allows more sweeps at the same walking speed.

“Sweeping is much faster,” says James Hagler, Ph.D., lead scientist on the study. “For small plots you will run out of your sample zone really fast with a sweepnet. So, it is better to use a vacuum. But, if you have a long sample zone, use the sweepnet.”

In a new study at the University of Arizona, researchers used body-mounted cameras to evaluate the efficiency of two insect pest sampling techniques—a sweepnet and a vacuum—in a cotton field. The perspective offered new insights into how such methods can be evaluated and could help growers and integrated pest management professionals further fine-tune their sampling techniques. (Photo credit: James Hagler, Ph.D.)

In a new study at the University of Arizona, researchers used body-mounted cameras to evaluate the efficiency of two insect pest sampling techniques—a sweepnet and a vacuum—in a cotton field. The perspective offered new insights into how such methods can be evaluated and could help growers and integrated pest management professionals further fine-tune their sampling techniques. (Photo credit: James Hagler, Ph.D.)

In a new study at the University of Arizona, researchers used body-mounted cameras to evaluate the efficiency of two insect pest sampling techniques—a sweepnet and a vacuum—in a cotton field. The perspective offered new insights into how such methods can be evaluated and could help growers and integrated pest management professionals further fine-tune their sampling techniques. (Photo credit: James Hagler, Ph.D.)

In a new study at the University of Arizona, researchers used body-mounted cameras to evaluate the efficiency of two insect pest sampling techniques—a sweepnet and a vacuum—in a cotton field. The perspective offered new insights into how such methods can be evaluated and could help growers and integrated pest management professionals further fine-tune their sampling techniques. (Photo credit: James Hagler, Ph.D.)

In a new study at the University of Arizona, researchers used body-mounted cameras to evaluate the efficiency of two insect pest sampling techniques—a sweepnet and a vacuum—in a cotton field. The perspective offered new insights into how such methods can be evaluated and could help growers and integrated pest management professionals further fine-tune their sampling techniques. (Photo credit: James Hagler, Ph.D.)

In a new study at the University of Arizona, researchers used body-mounted cameras to evaluate the efficiency of two insect pest sampling techniques—a sweepnet and a vacuum—in a cotton field. The perspective offered new insights into how such methods can be evaluated and could help growers and integrated pest management professionals further fine-tune their sampling techniques. (Photo credit: James Hagler, Ph.D.)

In a new study at the University of Arizona, researchers used body-mounted cameras to evaluate the efficiency of two insect pest sampling techniques—a sweepnet and a vacuum—in a cotton field. The perspective offered new insights into how such methods can be evaluated and could help growers and integrated pest management professionals further fine-tune their sampling techniques. (Photo credit: James Hagler, Ph.D.)

In a new study at the University of Arizona, researchers used body-mounted cameras to evaluate the efficiency of two insect pest sampling techniques—a sweepnet and a vacuum—in a cotton field. The perspective offered new insights into how such methods can be evaluated and could help growers and integrated pest management professionals further fine-tune their sampling techniques. (Photo credit: James Hagler, Ph.D.)

In a new study at the University of Arizona, researchers used body-mounted cameras to evaluate the efficiency of two insect pest sampling techniques—a sweepnet and a vacuum—in a cotton field. The perspective offered new insights into how such methods can be evaluated and could help growers and integrated pest management professionals further fine-tune their sampling techniques. (Photo credit: James Hagler, Ph.D.)

The befits of bodycams can reach far beyond arthropod sampling, the study suggests. All types of field research activity can be documented by the devices, says Hagler. “The video archives can be used to review scientific protocols and to pinpoint any discrepancies in the data collected by researchers,” he adds.

There is another benefit as well. The recording can be used as a training aid for new rookie field researchers. Besides teaching them the necessary techniques, it may also discourage slacking off on the job.

Ed Ricciuti is a journalist, author, and naturalist who has been writing for more than a half century. His latest book is called Bears in the Backyard: Big Animals, Sprawling Suburbs, and the New Urban Jungle (Countryman Press, June 2014). His assignments have taken him around the world. He specializes in nature, science, conservation issues, and law enforcement. A former curator at the New York Zoological Society, and now at the Wildlife Conservation Society, he may be the only man ever bitten by a coatimundi on Manhattan’s 57th Street.