Navigation Links
Bats pick up rustling sounds against highway background noise

Listening for faint rustling noises made by tasty beetles on a quiet day is simple for bats hunting with their exquisitely sensitive hearing. So try imagining what it must be like trying to locate rustling treats just metres from a roaring highway. It would seem to be almost impossible to pick out a centipede's footsteps as a juggernaut hurtles past; or is it? How animals that locate their prey by sound alone cope in our increasingly noisy world puzzles Bjrn Siemers from the Max Planck Institute for Ornithology in Germany. Siemers explains that no one had ever measured whether bats that hunt by listening for rustling insects are affected by man-made noise. However, this is a question that Siemers is frequently asked by urban planners keen to minimise our impact on local wildlife populations. Curious to know how sharp-eared bats react to loud background noise, Siemers and his colleagues Andrea Schaub and Joachim Ostwald monitored foraging bats' responses to rustling mealworms in noisy environments and publish their results on 19th September 2008 in The Journal of Experimental Biology on

Working with a group of young male greater mouse-eared bats, Siemers and Schaub allowed individual bats to forage freely in a large soundproof room. Dividing the back of the room in two, the duo provided the bats with a choice of rustling mealworm snacks in each half of the room to dine on. Over the course of several days, the bats divided their attention equally between the two halves of the room, easily locating the rustling nibbles. But how would the bats react when the team switched on a noise in one of the two dining areas?

First, the team synthesized true white noise before playing the sound in one half of the flight arena. The bats instantly avoided the unpleasant buzzing sound, spending more than 80% of their time hunting in the quiet dining area.

Next, Siemers and Schaub headed out to a local highway to record traffic sounds within 15m of the busy road. Back in the lab the animals were less bothered by the loud traffic noise than they had been by the white noise buzz. But they still preferred hunting in the quiet dining area, only spending 38.7% of their time gathering mealworms from the traffic noise booth. However, when the bats ventured into the noisy dining area they had no obvious problems locating their rustling prey against the traffic background.

More surprisingly, when the team played a simulation of a high wind rattling reed beds, the bats seemed to find it difficult to locate their prey and preferred foraging away from the sound, even though it was a noise that they encounter naturally in their day-to-day activities. So, man-made noise does interfere with bat foraging, but less than a very high wind rattling through vegetation.

Siemers admits that it isn't yet clear how man-made noise interferes with foraging bats as they listen out for a rustling lunch, but it probably does discourage these animals from foraging close to busy road networks. Keen to find out whether noise pollution affects foraging bat's hearing, or interferes with some other aspect of the bat's behaviour, Siemers is optimistic that his work will eventually result in bat-friendly road construction guidelines that will help to protect endangered bat species from our increasingly mechanised world.


Contact: Kathryn Phillips
The Company of Biologists

Related biology news :

1. Cells united against cancer
2. Progress Against Malaria: Developments on the Horizon
3. Genes that both extend life and protect against cancer identified
4. Gamma interferon could aid fight against fungal infections
5. In the laboratory, green tea proves a powerful medicine against severe sepsis
6. Omega-3 fatty acids protect against Parkinsons, study says
7. Protein protects brain against compound in lead poisoning, liver disease
8. Blood pressure drug telmisartan shows powerful activity against stroke
9. CWRU School of Medicine has evidence vaccine against malaria will reduce disease
10. A search for protection against chemotherapy cardiotoxicity
11. Translational research patented first experimental treatment against idiopathic pulmonary fibrosis
Post Your Comments:
(Date:6/22/2016)... , June 22, 2016   ... management and verification solutions, has partnered with ... software solutions for Visitor Management, Self-Service Kiosks ... provides products that add functional enhancements to ... provides corporations and venues with an automated ...
(Date:6/16/2016)... June 16, 2016 The ... expected to reach USD 1.83 billion by 2024, ... Research, Inc. Technological proliferation and increasing demand in ... expected to drive the market growth. ... The development of advanced multimodal techniques for ...
(Date:6/7/2016)...  Syngrafii Inc. and San Antonio Credit Union ... integrating Syngrafii,s patented LongPen™ eSignature "Wet" solution into ... result in greater convenience for SACU members and ... existing document workflow and compliance requirements. ... Highlights: ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... June 23, 2016 Houston Methodist Willowbrook ... Cy-Fair Sports Association to serve as their official ... Houston Methodist Willowbrook will provide sponsorship support, athletic ... with association coaches, volunteers, athletes and families. ... Cy-Fair Sports Association and to bring Houston Methodist ...
(Date:6/23/2016)... --  EpiBiome , a precision microbiome engineering company, today ... from Silicon Valley Bank (SVB). The financing will allow ... drug development efforts, as well as purchase additional lab ... been an incredible strategic partner to us – one ... provide," said Dr. Aeron Tynes Hammack , EpiBiome,s ...
(Date:6/23/2016)... Ky. , June 23, 2016 ... two Phase 1 clinical trials of its complement ... placebo-controlled, single and multiple ascending dose studies designed ... pharmacodynamics (PD) of subcutaneous injection in healthy adult ... subcutaneously (SC) either as a single dose (ranging ...
(Date:6/23/2016)... ... June 23, 2016 , ... ClinCapture, the ... Convention Center and will showcase its product’s latest features from June 26 to ... a scientific poster on Disrupting Clinical Trials in The Cloud during the conference. ...
Breaking Biology Technology: