Ep73 Magnus Wahlberg on bioacoustics, underwater noise and the interplay of ex-situ and in-situ animal conservation studies

<p>Magnus Wahlberg, a physicist and mathematician, was interested in biology. The thought of torture of laboratory animals put him off and he felt field biology may not be his cup of tea.</p> <p>Ironically, his voluntary work on marine animal sounds drowned him in fieldwork. He credits his mentors for their stimulating curiosity-driven approach. He had a long emotional journey of self-realisation that studying animals in captivity helps us know more about wild animals and vice versa.</p> <p>Listen as Magnus tells us about his interesting work on the bioacoustics of marine animals. With many exciting examples, he explains his focus on how animals hear. He explains how captive animals help test their field techniques before running field testing on wild animals.</p> <p>“Would you rather be deaf or blind?” asks Magnus as he explains with relatable analogies. When vision underwater is limited, one has to rely on hearing. He shares how water is a good conductor of sound, making it great for marine mammals to communicate information. He then goes on to explain how despite marine mammals sharing our physiology, they have adapted to living underwater.</p> <p>Magnus explains that ‘sounds’ can be defined as ‘noise’ or ‘signal’ depending on perspectives. The focal sound will be a ‘signal’ and the sound interfering with this will be ‘noise’. It is difficult, says he, to measure whether a sound is agreeable to an animal or not, since “some sounds are loud but not noise as they are part of an animal’s repertoire…”</p> <p>Discussing the effects of noise, Magnus explains that marine animals cope by either moving away or communicating louder (the Lombard effect). However, too much noise can result in death. Singular effects can be ignored but cumulative effects can keep animals in constant stress causing greater harm.</p> <p>Magnus shares that the construction of wind turbines is noisier than the operation. This issue does cause conflict between conservation biologists and climate change scientists. Personally, Magnus be