Navigation Links
Counting the invisible by sound -- a new approach to estimate seabird populations
Date:4/9/2014

AUDIO: This is a typical one minute recording of an active Cory's Shearwater colony on the island of Corvo in the North Atlantic Ocean, June 2011.

Click here for more information.

Seabirds nest in places that are inaccessible for most humans - vertical cliffs and remote islands surrounded by raging waves. Worse still, many seabirds lay their eggs in burrows or cavities where they are protected from inclement weather and invisible for researchers. Hidden under rocks or in burrows during the day, and flying around only during dark nights - counting these birds is a researcher's nightmare.

Despite their cryptic behaviour, the seabirds are ill-prepared to fend off furry invaders. Humans have brought cats and rats to many islands around the world, where the cats and rats roam freely and kill seabirds. Especially those seabirds that nest in burrows are often unable to escape, and many species have disappeared from islands where cats or rats have been introduced.

Although researchers have known for decades that many seabirds are in trouble, it is surprisingly hard to put a number on how fast populations decline. "Those species that are most vulnerable to rats are often the ones that are the most difficult to count" says Steffen Oppel, a Conservation Scientist with the RSPB who recently tested a new approach to count the invisible birds with colleagues from SPEA in Portugal.

Seabirds that nest underground may be all but invisible in their breeding colonies, but they are very noisy at night. And the more birds there are, the louder a colony is. Oppel and his colleagues set up sound recorders on a remote island in the North Atlantic for two years to 'count' the number of nesting birds by recording their calls at night. They painstakingly counted every nest near the recorders to test whether larger colonies do in fact make more noise. The study was published in the open access journal Nature Conservation.

"Recording seabird calls for a few months is the easy part - but making sense of 1000s of hours of sound recording is quite tricky" says Oppel. Together with Matthew McKown, a seabird researcher who specialises on sound recordings, the team developed an algorithm that automatically counted the seabird calls in terabytes of recordings. The results conformed with expectations: places with the most nests did indeed register the highest number of calls. With that relationship established, the team then extrapolated the seabird population size for the entire island - a number that had so far been derived from wild guesses.

"Estimating exactly how many birds nest on a cliff is not very precise" admits Oppel, but the sound recordings provide a very valuable index of how large seabird colonies are. "We can use this index over time to assess whether colonies are stable or decreasing - which is extremely important for many remote colonies about which we know very little".


'/>"/>

Contact: Dr. Steffen Oppel
steffen.oppel@rspb.org.uk
Pensoft Publishers
Source:Eurekalert  

Related biology news :

1. Scientists develop new carbon accounting method to reduce farmers use of nitrogen fertilizer
2. Countries should implement inclusive wealth accounting
3. Invisible helpers: How probiotic bacteria protect against inflammatory bowel diseases
4. Mafic melts, methane seeps, 2 million waves, foreign magma, and the invisible hand
5. Researchers manipulate tiny objects with ultrasound
6. SU biologists use sound to identify breeding grounds of endangered whales
7. Nanopores control the inner ears ability to select sounds
8. Ultrasound directed to the human brain can boost sensory performance
9. Trial to test using ultrasound to move kidney stones
10. Jailhouse wine is not as delicious as it sounds, could be deadly
11. Post-Sandy, Long Island barrier systems appear surprisingly sound
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Counting the invisible by sound -- a new approach to estimate seabird populations
(Date:1/22/2016)... , January 22, 2016 /PRNewswire/ ... announced the addition of the  "Global ... their offering. --> http://www.researchandmarkets.com/research/4lmf2s/global_behavioral ... the  "Global Behavioral Biometric Market 2016-2020" ... Research and Markets ( http://www.researchandmarkets.com/research/4lmf2s/global_behavioral ) ...
(Date:1/20/2016)... Minn. , Jan. 20, 2016   MedNet ... supports the entire spectrum of clinical research, is pleased ... 2015. MedNet,s significant achievements are the result of the ... iMedNet eClinical , it,s comprehensive, easy-to-use ... --> --> Key MedNet growth achievements ...
(Date:1/13/2016)... ALBANY, New York , January 13, 2016 /PRNewswire/ ... Transparency Market Research has published a new market report ... Share, Growth, Trends, and Forecast, 2015 - 2023. According to ... mn in 2014 and is anticipated to reach US$1,625.8 ... from 2015 to 2023. In terms of volume, the ...
Breaking Biology News(10 mins):
(Date:2/6/2016)... Virginia (PRWEB) , ... February 06, 2016 , ... ... E-mail: amitchell(at)cee(dot)org , The Center for Excellence in Education Sponsors Teacher Training ... VA – February 4, 2016 – The Center for Excellence in Education (CEE) ...
(Date:2/5/2016)... 5, 2016 Australian-US drug discovery and development company, ... appointment of a new Chairman, Mr John O,Connor , ... immediately. James Garner , has also been ... former Acting CEO, Mr Iain Ross , will resume ... --> James Garner , has also been formally appointed ...
(Date:2/4/2016)... Falls Church, VA (PRWEB) , ... ... ... a first-year cybersecurity conference presented by Bloomsburg University’s Digital Forensics Club, takes ... Bloomsburg, PA. The two-day event features 20+ speakers and activities such as ...
(Date:2/4/2016)... EDISON, N.J. , Feb. 4, 2016 ... company focused on the development and commercialization of targeted ... BIO CEO & Investor Conference 2016, to be held ... and Source Capital Group,s 2016 Disruptive Growth & Healthcare ... on February 10-11, 2016. James Sapirstein ...
Breaking Biology Technology: