Understanding the Sounds of Animals

Himanshu Choudhery

With the advancement of technologies over the past several years, the field of animal conservation has significantly evolved. Earlier, with the limitation of proper tools, there were many impediments to conservation programmes. Now, with the help of new tools such as bio-logging and bio-telemetry, camera traps, drones, sound recorders and advanced digital technologies, researchers can be precise and provide crucial information about target species and their habitat, and help them make better conservation strategies. There is a specific branch in the field of animal conservation called Bioacoustics (the study of producing, transmitting and receiving the sounds of animals) which is now considered as an important tool as it helps scientists and researchers to understand minor changes that are occurring in the ecological communities.

Importance of Bioacoustics in Animal Behaviour

Communication through sound in animals plays an important role in developing the relationships between them just like sound plays a very important part in the lives of humans. During communication, animals share information to each other which is very crucial to perpetuating the animal societies. This information sharing helps them to easily understand the species mood, identity, intentions and also assists them in reproduction. Thus, the communication behaviour in animals can be seen as a significant aspect which influences the development of life histories and genes in species.1

Clip: Juvenile pigs at a feeding site in Delhi. Credit: Ajay Immanuel Gonji

Bioacousticians have recently started to study the impact of human activities on the communication system of animals. Anthropogenic sounds such as traffic noise in terrestrial ecosystems have altered the communication of animals. According to researchers, songs produced by bird species in urban areas have often altered their performance in finding suitable mates. Due to the change in low-frequency songs in noisy habitat, the attractiveness of male is reduced in front of the females. Also, in some species such as frogs, noisy habitats have necessitated them to produce high pitch sounds which in turn affects them in a negative way as it hinders the process of mate selection (female frogs usually attract with low-frequency sounds).1

High anthropogenic sounds have not only disrupted the species sexual signalling but has also altered the species anti-predatory and foraging acoustic behaviour. For instance, the whispering sound produced by arthropods has disappeared in the noisy habitat which is directly influencing the foraging productivity of bats as bats generally use echolocation for hunting. Even in the marine ecosystem, the noise produced by boats, whale watching and military sonar activities have adversely disrupted the communication of marine animals. Noise pollution in the ocean has affected the life of cetacean species which mostly rely on the acoustic information for feeding, communication and other important activities.1

Most of the studies on animal communication are largely focused on natural environments such as forests and natural water bodies. However, rapid urbanisation around the world has created novel environments where animal species either adapt or fail to adapt. In human-dominated landscapes such as cities, animal species have altered their signalling amplitude and frequency to match with the human noise. These dynamic spaces provide an opportunity for researchers and scientists to learn how some species adapt while others abandon noisy urban habitats.1

In a sequel to this blog article, I will talk about the importance of bioacoustics in avian conservation and share some of my observations.

Reference

Featured Image by Wade Tregaskis

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