Technology and Conservation

Satellite imagery helps track changes in land use.
Satellite imagery helps track changes in land use. Astromujoff/The Image Bank/Getty Images

Nearly every facet of scientific research has been transformed by the technological leaps we have been experiencing. The study of biodiversity, and efforts to preserve it, has benefited from technology in many different ways. Many critical questions continue to be answered through the patience, skills, and dedication of field biologists who wield only a pencil, notebook, and a pair of binoculars. However, the sophisticated tools we now have available allow collecting crucial data at levels of scale and precision we never thought possible. Here are some examples of how recent technology has significantly advanced the field of biodiversity conservation.

Tracking by Global Positioning System

Old wildlife TV shows used to feature khaki-clothed grizzled wildlife biologists wielding heavy radio receivers and a large handheld antenna, tracking radio-collared rhinos or mountain sheep. Those radio collars emitted VHF waves, in frequencies not that far from those used by your local radio station. While VHF transmitters are still in use, Global Positioning Systems (GPS) are becoming the favored option for tracking wildlife.

GPS transmitters are affixed to the animal by way of a collar, harness, or even glue, from where they communicate with a network of satellites to establish a position. That position can be transmitted in turn to the now desk-bound wildlife biologist, who can follow her subjects in almost real time. The advantages are significant: disturbances to the animal are minimal, risks to the researcher are lower, and cost to send crews out in the field are reduced. Of course, there is a price to pay. The transmitter are more expensive than conventional VHF ones, and the GPS units have yet to be compact enough to be used for the lightest animals like bats or small songbirds.

Another great feature of satellite-based transmitters is the ability to transmit more than just location data. Speed can be measured, as well as air or water temperature, even heart rate.

Geolocators: Miniaturized Trackers Based on Daylight

Migratory bird researchers have long wished they could track their subjects during their long annual flights to and from wintering grounds. Larger birds can be fitted with GPS transmitters, but the smaller songbirds cannot. A solution came in the form of geolocator tags. These small devices record the amount of daylight they receive, and through an ingenious system can estimate their position on the globe. The geolocators’ size come at the cost of not being able to transmit data; scientists have to recapture the bird upon its return the following year at the study site in order to recover both the geolocator and the data file it contains.

Because of the unique system used to estimate location, precision is not very high. You may, for example, figure out that your study bird is spending its winter in Puerto Rico, but you will not be able to tell near which town, or in which forest. Nevertheless, geolocators have assisted in making exciting discoveries in the world of migratory birds. For example, a recent study revealed the migratory path of red-necked phalaropes, a small seabird, as they flew from northern Sweden to winter in the Arabian Sea, with refueling stops in the Black and Caspian Seas.

Detection Using Environmental DNA

Some animals are difficult to observe in the wild, so we need to rely on signs of their presence. Looking for lynx tracks in the snow or counting muskrat nests relies on such indirect observations. A new method based on this idea helps determine if hard-to-see aquatic species are present in water ways by looking for environmental DNA (eDNA). As skin cells are naturally sloughed off fish or amphibians, their DNA ends up in the water. Advanced DNA sequencing and barcoding allow identifying the species that DNA comes from. Ecologists have used that technique to determine whether invasive Asian carps had reached the Great Lakes watershed. A very large but difficult to detect salamander, the endangered hellbender, has been surveyed in Appalachian watersheds by testing the creeks for eDNA.

Unique Identifiers with PIT tags

To estimate wildlife population size, or measure mortality levels experienced, individual animals need to be marked with a unique identifier. For a long time wildlife biologists have been using leg bands on birds and ear tags on many mammals, but for many types of animals there was no effective – and lasting – solution. Passive Integrated Transponders, or PIT tags, solve that problem. There are very small electronic units encased in a glass shell, and injected into the animal’s body with a large gauge needle. Once the animal is recaptured, a hand-held receiver can read the tag and its unique number. PIT tags have been used in a large variety of animals, from snakes to coyotes. They are also increasingly popular with pet owners to assist in returning their wayward cat or dog.

Acoustic tags are a close cousin of PIT tags. They are larger, contain a battery, and actively emit a coded signal which can be detected by receivers. Acoustic tags are used in migratory fish like eel and salmon, which can be tracked migrating up and down rivers and through hydroelectric dam complexes. Judiciously placed antennas and receivers detect the passing fish and thus can track their progress in real time.

Getting the Big Picture Thanks to Satellites

Satellite imagery has been around for decades and conservation biologists have been able to use it to answer a wide variety of research questions. Satellites can track Arctic ice, wildfires, rainforest deforestation, and suburban sprawl. The available imagery is increasing in resolution and can provide crucial data on land use changes, allowing the monitoring of environmentally challenging activities like mining, logging, urban development, and the resulting wildlife habitat fragmentation.

A Bird’s Eye View from Drones

More than just a toy or a military tool, small unmanned aircraft can be used for biodiversity research. Drones carrying high-resolution cameras have been flown to observe raptors’ nests, track rhinos, and to precisely map out habitat. In one study in New Brunswick, a drone allowed biologists to count hundreds of common tern nests with minimal disturbance to the birds. Harassment of wildlife from these buzzing drones is a real concern, and many studies are underway to evaluate how these tools' incredible potential can be used with as little disruption as possible.