Storm-Watching Radar Systems Find Another Use: Bat-Tracking

By Patrick Morgan | February 22, 2011 4:53 pm

In the realm of meteorology, bats, birds, and insects are usually considered “animalas non grata,” since they create unwanted noise in the Doppler radar readouts used to study storms. But now, thanks to better radar station networking and the sharing of unfiltered data, ecologists have realized that these radar systems can be used as powerful animal tracking tools.

At last week’s American Association for the Advancement of Science meeting, researchers Thomas Kunz, Winifred Frick, and Phillip Chilson explained how Dopplar data can be used by ecologists. They call their new discipline aeroecology.

This melding of meteorology and ecology started with an “Aha!” moment:

“Dr Kunz and I were meeting Dr Chilson about a year ago over breakfast and they kept talking about the ‘QPE’, and finally I asked what it is,” Dr Frick told the meeting. It stands for quantitative precipitation estimator — a numerical method to measure how much rain there is in a storm front. “I paused and said, ‘you can estimate the number of raindrops in a raincloud? Do you think we could estimate the number of bats in a bat cloud?'” To calibrate their experiment, the team took a bat into a chamber where the degree to which it reflects radio waves could be measured. “From those measurements and using radar, we’ve been able to adapt those QPE measurements to a ‘QBE’ – a quantitative bat estimator,” Dr Frick said. [BBC News]

In the past, animals like bats have been tough to track due to the size of radio transmitters: these tracking devices work well on large animals, but they’re too large for many kinds of birds, not to mention bats and insects. But a radar system removes the need for transmitters, and can allow researchers to examine the under-explored ecology of the air.

In one new initiative from the National Severe Storms Laboratory in Norman, Oklahoma, meteorologists put the data from 156 NEXRAD radars across the United States on to a map; now all that data is available to biologists in a project called Surveillance of Aeroecology. The map is updated 12 times every hour, and the researchers hope to improve the resolution to get better images of insect swarms and flocks of birds.

The use of meteorological data saves ecologists from having to invest money in equipment, and they’re already reaping the benefits:

At the meeting, Frick described how, in a radar sequence from southern Texas, she had seen something she had never imagined: swarms of bats following an evening weather front. “Radar is like a really fancy pair of binoculars,” Frick said. In the radar view of a storm front rolling over Texas, Frick pointed out a frayed tan bar indicating insect swarms moving with the air mass. The radar doesn’t reveal much about the identity of species in a cloud, but Frick knew that the front was passing over a bat cave. A yellow burst on the radar showed what Frick identified as dense crowds of Brazilian free-tailed bats speeding out of their cave at sunset to hunt for insects. The burst bloomed into a cloud of bats, with an elongated mass sliding west along with the bugs. “It’s a big aerial buffet line,” Frick said. [Science News]

Better tracking of animal behavior can also aid conservation efforts for various bats, birds, and insects. Researchers hope the field will grow quickly, because they’re not building their data banks from scratch: Radar stations have decades of data just waiting for the sharp eye of an aeroecologist.

Related Content:
80beats: The Original Bat-Signals: Bats Can Recognize Individual Voices
80beats: Radar May Keep Bats Away From Wind Turbines’ Blades
Science Not Fiction: Built-in Superpowers: Echolocation Among the Humans
80beats: Great Minds Think Alike: Bats & Dolphins Evolved Same Gene For Echolocation
Bad Astronomy: Radar love

CATEGORIZED UNDER: Living World, Technology
  • Brian Too

    NA-NA Na-Na na-na Na-Na BAT-DAR!!

  • Steven Purcell

    “…as dense crowds of Brazilian free-tailed bats…”

    Shouldn’t that be MEXICAN free-tailed bats?

    Cool study and it will be interesting to see these techniques developed further.

  • pozycjonowanie

    Just wish to say your article is really as amazing. The clearness in your post is simply excellent and i could assume you are a pro on this subject. Well with your permission let me to grab your own RSS feed to keep up to date with coming write-up. Thank you a thousand and please keep up the rewarding job.


Discover's Newsletter

Sign up to get the latest science news delivered weekly right to your inbox!


80beats is DISCOVER's news aggregator, weaving together the choicest tidbits from the best articles covering the day's most compelling topics.

See More

Collapse bottom bar