As I See It: Biology On The Wing
October 19, 2015 Victor Rozek
The solemn pod arcs in unison and disappears beneath blue water, leaving telltale plumes dancing in the breeze. I’m perched on weather-carved rocks on the extreme southern end of a small Canadian island called Saturna, watching a pod of killer whales sweep around the point. They pass by a mere stone’s throw from shore, on their way to ancient feeding grounds. But they are not alone. A hundred yards beyond, a picket line of boats filled with grasping tourists tracks their every breach. Once hunted, they are now annoyed. Once victims of persistent greed, they now endure persistent curiosity. From Alaska to Baja, these great travelers, so sensitive to sound, are hounded by the incessant roar of boat engines. Oh, how we love whales; just not enough to leave them alone. It is a dilemma familiar to wildlife biologists. In order to study animal populations, they must track their movements. But in such a way as not to alter their behavior, or cause them unnecessary stress. Many migrating animals cover such vast distances that aerial tracking is the only practical alternative. But low altitude reconnaissance over rugged terrains presents its own risks. According to Audubon, “light-aircraft crashes are the No. 1 killer of wildlife biologists.” Ironically, the solution to many of the challenges facing field biologists comes in the form of a technology that, in other contexts, has proven to be both annoying and deadly: the drone. NOAA Fisheries and the Vancouver Aquarium teamed to study the health of endangered killer whales. For the first time, scientists have used an unmanned aerial vehicle to study whales from above. A hexacopter with a high-resolution camera mounted in its belly is used to track resident pods in British Columbia from a height of about 100 feet–high enough not to be annoying, but low enough to produce extraordinarily detailed photos. The main objective is to discover if the mammals are getting enough to eat. These Orcas are very specialized eaters and Chinook salmon are their meal of choice. A full-grown Orca must eat about 17 salmon each day to maintain nutritional requirements that can exceed 250,000 calories. But salmon populations have been stressed by overfishing and habitat degradation. Each whale has unique markings, and drone technology allows researchers to see how fat or skinny individual whales are becoming, which females are pregnant, and what percentage of pregnancies is carried to term. Given the interconnectedness of all things natural, healthy whale populations depend, in part, on healthy populations of salmon, which in turn require healthy watersheds. It is hoped that the observational data collected by drones may lead to recommendations for systemic changes that will allow both salmon and whales to flourish. Sixty-seven hundred miles south-east in West Africa, medical professionals and wildlife biologists hope that drone surveillance may head off the next pandemic. Hammerhead fruit bats are one of three species of bats thought to be reservoir hosts for Ebola (meaning they carry the virus without succumbing to it). Researching these bats in close proximity poses obvious risks, and given that the bats are nocturnal, tracking their movement is problematic. Of particular concern is any contact bats have with primate populations that are a food source for local villagers. The last Ebola outbreak is believed to have been spread by the sharing of infected meat. If drones can provide even an imperfect early warning system, alerting officials to the possibility of an outbreak, it would no doubt be a welcome step in prevention and containment. As Audubon notes, hard-to-reach places, and places where observers would not be welcome, are perfect venues for the snooping capabilities of drones. “Orangutan nests high in the jungles of Sumatra and Borneo,” for example, are both hard-to-reach and likely to be aggressively defended from intrusion. But beyond observing skittish animals, drones have also become useful in monitoring illegal human activity such as unauthorized logging and poaching. In Central Africa, “where dead elephants finance terrorism,” a custom-made GPS and satellite-based tracking system (in this context satellites can be thought of as orbiting drones) concealed in faux ivory, were used to track the movement of illicit ivory. As detailed in the cover story of the September 2015 National Geographic, the grisly cargo was moved “600 miles from jungle to desert” heading to the base of a Sudanese warlord. The problem is staggering in scope. Tanzania alone has lost 60,000 elephants to poaching in the last five years. About 30,000 are slaughtered annually by rebel groups and organized militias. Most of the ivory ends up in China, and neither the demand nor the killing is slowing. In saner venues, the drone revolution has freed researchers from some of the inherent discomforts of fieldwork. Biologists no longer have to sit in remote, inhospitable sites for days on end waiting for migrating birds to arrive; or track a wolf pack on the move. Nor must they compromise accuracy by estimating animal counts. Drones “carry digital cameras that produce geo-referenced photos, the data they gather can be fed into image-recognition algorithms to vastly improve the accuracy of population counts.” Animals that have been tagged can transmit real-time data to drones. “The tags use a suite of sensors to log a creature’s GPS position and direction of movement. Such information allows researchers to look for movement signatures that indicate when the animal is hunting, eating or scavenging. If it is killed by a poacher, or poisoned by a pesticide, motion will cease. Likewise, sensors that measure temperature, humidity and elevation can help researchers deduce if a changing climate is altering an animal’s range.” There is a dictum in quantum mechanics that says the presence of an observer changes the nature of the observed. It’s not clear if that applies to drones. What is clear is that drones offer a less invasive, more efficient, and far safer method of data collection that is revolutionizing field biology. About 700,000 drones are expected to be sold in the U.S. this year alone. Some will no doubt be used to invade the last of our privacy; but at least a few will fly in service of nobler aspirations. It’s an encouraging start.
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