Washington state to fly drones in endangered mini-rabbit count

Wildlife officials in Washington state are set to deploy drones over a large expanse of preserved space as part of their annual effort to estimate the population of the nearly extinct Columbia Basin pygmy rabbits.

The Washington Department of Fish and Wildlife is preparing to begin daily drone flights over state and federally managed lands covering two counties as part of a trial-cum-annual-census of the tiny rabbits. The distinct species is the smallest among North America rabbits, and typically never grows larger than 12-inches long or more than 16 ounces in weight. Due to incursions of animal, natural, and human threats over time, the estimated population has decreased to a mere 100 to 150 individuals.

Washington game authorities will use the drones to scan enclosed zones they’ve created to preserve sagebrush and terrain the rabbits live in and burrow into – the only species to create their own underground shelter. Due to the size, color, and understandably furtive instincts of the animals, humans have a very tough time catching sight of them, much less distinguishing one from another for count purposes. 

Read: Oz partners fly drones to regenerate habitat of declining koala populations 

The drones will therefore be used as a faster and hopefully more efficient method of spotting probable burrow sites before Washington wildlife experts – who usually must scour the areas on foot for signs of rabbit activity ­– are sent in for a closer look. Once there, they’ll take a count of active habitats – which allows them to calculate the approximate residents within – and collect droppings for use in genetic analyses.

Washington Department of Fish and Wildlife authorities say the drones will start overflying the two protected sites maintained to facilitate the rabbits’ reproduction between 8 a.m. to 5 p.m. starting this month through March.

The exact timing of those outings – like that of the annual census campaign – will seek to ensure there’s sufficient snow covering the ground to make spotting traces of the creatures easier, and verify the craft can withstand often difficult weather.

“The purpose of these flights is to test drone and sensor capabilities and effectiveness for tracking pygmy rabbit distribution and numbers in snowy conditions,” said Taylor Cotten, Washington Department of Fish and Wildlife’s conservation assessment section manager. “Researchers will also use the drones to help determine the survival rate of reintroduced pygmy rabbits.”

Use of the drones to keep track of the rabbit population was inspired by the use of aerial tech by wildlife experts in Washington and other states to take counts of creatures ranging from ground squirrels to mountain goats, salmon to whales. 

Sadly, however, even using those higher vantage points, the effort to identify traces of the rabbits (much less the critters themselves) is getting to be like finding needles in a haystack. 

The campaign to facilitate repopulation through captive and enclosed breeding areas began after the last known individual was born in the wild in 2008, and started using three protected Columbia Basin spaces. One of those was wiped out by a fire in 2020, killing an estimated 43% of all remaining rabbits. 

However, survival rates of generations born since give experts hope the species may survive yet – with a bit of human help – despite their diminished numbers. 

Photo: Washington Department of Fish and Wildlife