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1948 - Eyes in the Sky: Counting Big Game

Simply counting animals visible from the air is considered to be a minimum count because animals are likely missed during the flight surveys. When radio collaring animals and radio telemetry became available in the 1970s, biologists could more easily find and count animals. This new radio telemetry led the department to develop a more accurate method of estimating elk and deer.

In the Lochsa River drainage, with its dense forests, Idaho Fish and Game research biologists went on to develop a sightability survey model to adjust for animals not being seen and counted on the aerial surveys.  It estimates the probability that groups of animals will be seen given certain variables, such as terrain and snow cover, and adjusts the populations estimate for animals that would not be seen and counted under these conditions. The survey model has since been adopted by many western states for their aerial survey work.  

Aerial surveys have proven to be the most effective tool for gathering big game population information, but it is expensive. The average cost of an hour in the air is $800.  Yet, even with this price tag, surveying wildlife from aircraft is more cost effective than ground-based approaches.  

The nature of the kind of flights needed to conduct aerial surveys also has inherent risks.

Biologists need certain conditions to be able to collect the detailed information of age and sex of animals during their aerial surveys.  They need clear weather for good visibility and snow covering to aid in locating animals. The aircraft needs to fly low and slow for biologists to be able to determine sex and age of the animals being counted. Add in rugged, remote terrain and elevations ranging from near sea level at Lewiston to over 10,000 feet new Mount Borah, and the risk level quickly multiplies.  Over the years, accidents have happened and biologists and pilots have died.

Idaho Fish and Game is looking at new technologies that provide safer ways to collect accurate and reliable information needed for big game management decisions.  Advances in remote controlled UAVs, unmanned aerial vehicles or drones, offers the most promising alternative.  Drones capable of taking aerial photos or video are already being tested in Idaho and by other state wildlife agencies.  For example, drones have been used to search for pygmy rabbits in Idaho, study seals and sea lions in Alaska, monitor rare plant species in Hawaii, and count Sandhill crane populations in Colorado.

Drones are not likely to replace all helicopters, airplanes and highly trained human observers. But as they improve and they become affordable, drones have the potential of substantially reducing the cost and human risk connected to aerial surveys.