Collecting Bird Songs for Posterity
Meet IFS officer Pratap Singh whose all-consuming passion for recording bird songs from the wilderness has resulted in a huge repository.
Birds may have small brains but that does not make them less intelligent than mammals. In fact, recent studies have shown that they have more neurons packed into a square unit of area than most mammals or even primates, explaining their remarkable cognitive abilities. From making tools of twigs or building intricate nests, to placing nuts to be cracked by vehicles on busy roads, or recognizing themselves in a mirror, corvids and other families of birds have proven that birds are often second only to humans in intelligence.
Among the many endearing and awe-inspiring tricks up their feathers is the ability of birds to compose songs. Besides the tunes that are unique to each family of birds is the ability to mimic, or ‘steal’, each other’s songs. Not only do some borrow notes from other birds, they can even pick up prominent and common sounds in their surroundings. This ability to learn, call it borrowing or plagiarism, is a clear indication of bird intelligence.
The Australian Lyre bird for instance even imitates the sound of the camera, replete with the clicking and shutter sounds. Car alarms, chainsaw sound, etc are mimicked by the males to outdo their rivals and win a mate. Back home, the racket-tailed drongo is a clever bird that mimics cats and over 30 species of birds, few insects and frogs.
Tracking bird notes and songs are some avid birders, among who PCCF Dr Pratap Singh, IFS features prominently. Wherever an opportunity arises, off he goes into the woods or grasslands, carrying his recording system made up of a satellite dish-like parabola with an attached microphone.
The parabola funnels sound waves towards the mic and is good if one is looking for reach and directionality, he notes. While it is good with high frequencies, it is not so for lower frequencies of songs.
This senior officer, presently posted with the Wildlife Institute of India, has collected vast number of bird songs since he began tracking them from 1987 when posted as a forest officer in Arunachal Pradesh. The dense forests there made him realise the importance of bird sounds to identify the birds.
“The bird sounds are important resource for research, education and conservation,” says Dr Singh, adding that many new bird species are being discovered based on sounds which often provide the first clue of presence of potential new species.
The recordings can be used in places where bird population is down. The breeding time vocalization when played artificially can attract the birds and excite them to breed in artificial nests, he explains. In South-east Asian countries, people use sound playbacks to attract Ediblenest Swiftlets to dark buildings to nest, so that they can harvest their edible nests sustainably, which fetch good price in the markets.
Singh has contributed towards making educational products which are freely available. Some of these are “Birdsongs of Great Himalayan Conservation Area” – a collection of bird-songs of Himachal Pradesh, “Piyu”- an audio-visual compilation of about 150 bird songs of Central India, “Bird songs of Uttarakhand” an audio-visual compilation of 200 species, etc.
Recording bird songs is a joy in itself and full of excitement, he says. He has studied and observed birds across various landscapes of the country. From recognising the blue throat in Ladakh when it mimics the common red wattled lapwings, to himself mimicking a call to confirm a bird species, Dr Singh is a repertoire par excellence on birds.
It all began as a necessity back when posted in Arunachal. “With the vegetation being dense, it often was difficult to see the bird. That was when I decided to record their songs and try identify them,” says Dr Singh. He began with an ordinary analogue audio recorder till in the 90s he saw some birders at Namdapha reserve carrying the parabola. He got himself a second-hand equipment. It was costly back then and very difficult to get in India. But he was sufficiently hooked by then to the ‘chase’.
His hobby turned into research and he did his doctorate on the geographical variations of birdsongs in Himalayas. As part of the study he looked in depth at the Grey-hooded Warbler and Blyth’s Leaf Warbler, two leaf warblers breeding in Himalayas and in the hills of the North-eastern State. These two species belong to a large family of birds called Phylloscopidae, members of which are morphologically very similar and best identified by their calls, he explains.
The songs of these two birds may sound similar to a novice but differ significantly from each other. The Grey-hooded Warbler sings with repetition of song units before switching to another song type and has a large song repertoire of eight to 12 song types across localities, whereas the Blyth’s Leaf Warbler rarely repeats a song type and sings with fewer songs, rarely exceeding three.
From simple notes to long-drawn songs, bird song notes usually get complex as one goes further north from the tropics. Several hypotheses around increasing competition during breeding, short periods before pairing, abundant food allowing the birds to indulge in complex songs, etc have been suggested. But in the case of the commonly found warblers, it was seen that more complex songs emanated in the western temperate side though food is less there.
The study found that in the two species, aspects of song complexity were higher in populations occupying less species-rich habitats. Song complexity is a compound trait, though it often does correlate with latitude and complex songs are noted in higher latitudes where fewer species are present. Reduction in habitat complexity and species numbers too contributed to complexity. With signals distorted by vegetation and background noise, the birds may sing over smaller bandwidth and keep it simple just to be audible in noisy situations, said the study.
Now, Dr Singh is working with other scientists on how song signals have evolved in the leaf warbler family Phylloscopidae and a group of babblers having similar songs.
To him, every trip is exciting as it throws up the possibility of finding some new sound, a new bird in an old area or an old one with different sound in a new area! “I go looking for some species in a place and often find many more. Often, I come across long melodious songs and I am spellbound. I basically follow sounds but if I can’t recognise sounds I try follow and see the bird visually.” That was how in when posted in Andamans, he took time to identify the endemic Andaman crake the first time he heard the deep croak. But later this bird, assumed to be rare, became commonly heard, once the right time and habitat were picked, says Dr Singh.
Today, recording bird songs and natural sounds has become comparatively easy with the advancement of recording technology. One can buy very handy and user-friendly recording equipment within the country, and depending on one’s budget, the choices are many, he notes. There is a huge amount of learning material available online for the needs of beginners as well as advanced recordists. There are online archives like Xeno-Canto, Macaulay Library and British Library where one can deposit the recorded sounds and can also borrow sounds for their research.
“People take to sound recording for various purposes, some record species like birds, frogs, insects, mammals others record ambient sound of quiet places, sound of streams, sea-waves, sand-dunes… the list is endless. Whatever may be the objective, recording sound is like recording history—a clip of sound recorded at a place may be a unique recording as soundscape is continuously changing,” points out Dr Singh.
The sound clip also contains huge amount of other acoustic information about the place, both of biotic and abiotic origin. “Keeping personal nature-sound libraries and depositing in archives can greatly contribute towards documenting nature, besides being a joyful nature-based activity in itself,” he says.
The records are all there, and ever increasing with each outing Dr Pratap Singh undertakes — parabola held high and his senses alert to any new tune being sung in the wilderness.
Written by Jayalakshmi K