Eptesicus FuscusVS

Bertholdia Trigona

The Experiment

Background Info

In Nature, bats use ultrasonic radars to capture prey

Hypothesis: Ultrasonic clicks produced by moths jamming radar of bats?

Experiment conducted in controlled area with two naive brown bats and one experienced brown bat

Two types of moths were used: clicking and non-clicking moths

Background on batTheory that bats will not attack if it hears the clicking of moth

Clicks might cause bat to become confused in environment?

Bats use echolocation to capture prey because they are most reliant on their ears, not eyesight

Rationale for Experiment

Experiment with moths with high acoustic clicks like the Bertholdia Trigona (aka Tiger Moth)

To observe the affects of the clicking of moths on the brown bats

Prove that clicks alone do not cause bats to stop attacking moths

no accompanied bad smell or taste

What was used?

Experiment was conducted in a dark room

Four bats were used (Brown Bats) E. fucus

Only three were observed, 2 naive bats and 1 experienced bat.

Different types of moths used

Tiger moths and wax moths (four silent tiger moths and 8 wax moths)

wax moths used for training naive bats

How they did it?

There were multiple nights of testing

Sensitive (High Speed) Infrared Cameras

observe bat behavior and attacks on moths

Ultrasonic microphone

Used to record the clicks and sounds of moths and bats

Control Group

Bats were put into flight room with wax moths

wax moths became control group

Bats hunted wax moths regularly, and without difficulty

Bats came in contact 100% with the wax moth control group

What Happens now?Tethered and non-tethered moths used in flight rooms

In the 9 nights, 7 of the nights had the clicking tiger moth with the 3 brown bats

Bats were observed, still attacked tiger moth, however all three bats had difficulty

The last two nights, non-clicking moths were presented

Bats hunted the moths like regular prey, no difficulty in capturing

Conclusion

Tiger Moths able to jam sonar with clicks

Experienced bats still had difficulty capturing B. Trigona

Tracking prey had an irregular pattern (terminal, track, approach etc)

Loud clicking moths are more effective in sonar jamming than low clicking moths

ExperimenT Suggestions

Have a bigger group of bats

More natural environment

More time

Additional Questions

Could it be possible that the clicking of the moths cause loss of sense of direction.

Will the brown bat be able to adapt to the clicks of the moths over time?

Sources

http://csm-premed-2010.wikispaces.umb.edu/file/view/moth+jams+bat+sonar.pdf

http://www.livescience.com/5578-wow-moths-jam-bat-sonar.html

http://www.scientificamerican.com/article.cfm?id=sonar-jamming-tiger-moths-bats-echolocation-defense