What is it that enables your Mynah bird to learn to speak more than 100 words and utter as many as 30 sentences?

Lingual articulation  is one method of altering the resonance properties of the vocal tract in animals.  A Mynah bird can move their tongue around their mouth and shift frequencies to make human-like vowel sounds (Klatt and Stefanski, 1974). The ability of Mynah birds and parrots to modify formants (a prominent band of frequency that determines the phonetic quality of a vowel) contributes to a Mynah bird’s ability to imitate human speech.

We used to think that a bird’s vocalisation repertoire depended on how sophisticated its syrinx was”

- Peter Marler of the Rockefeller University Field Research Station in Millbrook, N.Y. Dr.. Marler, one of a number of research biologists who specialise in animal communication.

A bird’s syrinx, the functional equivalent of a human’s larynx or voice box, is much simpler than the human vocal apparatus. Most bird syrinxes are the same, so what makes a Mynah bird different? The answer is their brain

Mynah birds have unique brains to allow them to learn

When most birds chirp or sing they’re making noises that are hardwired into their DNA, but Mynahh birds can create new vocalisations which scientists call Vocal Learning. Not only that but something about a Mynahh birds’ neurons make them incredibly good at vocal mimicry replicating the sounds or calls of other species, including humans. The Greater Indian Hills Mynahh bird is one of the best talkers.

What is Vocal Learning?

“Vocal learning is the ability to modify acoustic and/or syntactic features of sounds produced, including improvisation and imitation.”

Only three types of birds are capable of vocal learning, hummingbirds, songbirds and parrots. They all have 7 clusters of neurons in their braids called song nuclei. As other birds don’t have these brain regions scientists think this is what allows the birds to learn.

Are male Mynah birds better talkers than female?

Recent studies show that the part of a bird’s brain that controls its vocalisations is in the front of the skull, and corresponds roughly to the human cortex. The males of almost all songbird species are the principal vocalisers, and the male forebrains, which control their song output, have been found to be larger than the forebrains of females. But this does not necessarily mean that males are better talkers than females. 

‘Mynah birds … only begin to learn human speech sounds under certain social relationships,” Dr. Marler said. ”To get a Mynah bird to talk you must intrude on its social life.” 

Such ‘intrusions’ would include feeding your pet bird by hand and, in effect, having the bird imprint on you as if you are its parent. Mynahs are known to form strong bonds with their owners and the more interaction and conversation you have the more likely they are to mimic you. So boy or girl, it’s entirely up to you to train them to talk.

How a Mynah birds syrinx works to enable them to talk

Here’s the biology behind the ability for your minor bird to form sounds that are so close to human speech. In your Mynah bird the syrinx is located at the bottom of the trachea. Sound is produced at the syrinx in an air stream whose speed and volume is controlled by muscles in the trachea. Sound generated in the syrinx travels to the beak through the resonance filters of the supra-syringeal vocal tract.  

Mynah birds have articulate tongues to help them make vowels

The syrinx has two resonating membranes, and they can be independently controlled, enabling the bird to produce two different notes simultaneously. By using their articulate tongue and beak as a resonance filter your Mynah bird can alter these sounds quite specifically to try and mimic what they hear.

One of the paired external labia in the syrinx is implicated as the source of voicing energy (analogous to the human vocal cords). Some or all of the formant resonances ( the vowel frequencies needed)  are produced by exciting the mechanical resonant modes of the internal tympaniform membrane in the syrinx. 

The five pairs of intrinsic muscles that are associated with the syrinx are capable of controlling membrane tensions and regulating the position of the external labia in the syringeal airways during sound production.

So there you have it, Mynah birds are one of the best mimics of human speech because of their anatomy, their brain and their ability to bond with their owner. Enjoy your new companion and have lots of fun, but be careful what you say around them, they often mimic the words you don’t want them too!

Efforts on to protect Chattisgarh’s state bird from extinction

• • • • The bird is endemic to the Kanger Valley National Park where the felling of several dry trees for cultivation, especially sal, and infrastructure development activities has put the species in danger.
      • The forest department along with conservationists is planning to further study the bird and make efforts towards conservation activities for the protection of the bird population.

The Kanger Valley National Park in Bastar district of Chhattisgarh is a mysterious place dotted with caves, waterfalls and dense forests. The protected area notified in 1982 is also famous for the Bastar hill Mynahh (Gracula religiosa peninsularis), a species placed under Schedule 1 (b) of the Wildlife Protection Act, 1972. The Chhattisgarh government declared it as the state bird in 2002.

The jet black coloured bird mimics the human voice exceptionally well. For this reason, it is often found in cages and sold as pets in the market. The distribution range of the common hill Mynahh includes India, China, Thailand, Sri Lanka and the South East Asian islands. There are 12 sub-species that are very similar but separated by their distribution range, according to a 2020 study. In India, four sub-species of the common hill Mynahh are found.

The Bastar hill Mynahh is endemic to the Kanger Valley National Park, where the felling of several dry trees for cultivation and developmental activities has put the species in danger. The hill Mynahh nests in colonies, along with parrots and woodpeckers. Holes made by woodpeckers in dry sal (Shorea robusta) trees are preferred by the hill Mynahh. In Bastar specifically, there are 11 resident woodpecker species that make holes regularly in several trees. The Bastar hill Mynahh surveys each hole and then chooses a nest after multiple visits.

“There are 14 sites across Kanger Valley where the birds come for eating fruits during the fruiting season and are spotted. My three-year observation says that the birds need dry trees, about 20-25 metres in height, near water sources. It needs this much height for security reasons,” Ravi Naidu of CROW (Conservation and Research of Wilderness) Foundation, a non-profit based in Jagdalpur, Bastar, told Mongabay-India. Naidu and Ameet Mandavia of CROW have studied the species in detail for some years. Apart from deforestation and almost zero patrolling in Kanger Valley due to Maoist presence, Mandavia informed that the bird is also hunted by tribal people. “Trees which support the hill Mynahh should be grown to support its decreasing population. Banyan trees are suitable for them as they bear fruits twice a year. If a tree does not have fruits, the Mynahh will not sit in it,” he said.

Is the count decreasing?

The population of the hill Mynahh in Chhattisgarh stands at 350-400 birds if scattered populations from other nearby districts of Bastar are taken into consideration, according to Newsletter for Birdwatchers September-October 2017. Though there is no recorded data, there have been reports of flocks disappearing. In an unofficial count by CROW Foundation, 100 breeding pairs were reported. “A total of 100 breeding pairs were counted. Counting was on for five years till 2016 and the report was published in 2017. Obviously, the population has reduced. About 20 years ago, a flock size of 200-300 birds used to be seen. Now spotting even five to six birds in a flock is a most fortunate thing,” Mandavia added.

But it is incorrect to deduce that the population is decreasing or increasing as there is significant local movement of the species, explained Bharos, co-author of the 2017 Population Assessment And Status Of Common Hill Mynah study and a Raipur-based wildlife expert. He added that the birds congregate wherever food is available. Assessment of their population is not easy as they travel long distances, sometimes even to the neighbouring state of Odisha in search of food. “Once, in the Kanger Valley National Park, I counted 40 birds and they were converging and leaving at the same time which made counting difficult. I think it is more or less static in Kanger Valley which is a good indication,” he said.

Attempting captive breeding

A captive breeding experiment was initiated by the forest department in the early 2000s at the forest training school in Jagdalpur, but it didn’t have any success. Talking about the project, Vijaya Ratre, the director of Kanger Valley National Park, said, “There is a cage where we have now kept two birds (after the death of birds during the captive breeding project). It is tough to identify the male and the female as the sexes do not have any distinguished features for easy identification.” Both sexes are visually similar and can be identified only after plucking their feathers or when they mount each other during mating. “Captive breeding was thought about to add on to the population but we could not get success. It is a rare bird and its distribution is limited. It is found in parts of Andhra and Odisha as well. In Chhattisgarh, it is found in the Bastar region,” Ratre said.

Rahul Kaul, senior director at the Wildlife Trust of India, said captive breeding is usually carried out as an alternative option to prevent decline in the wild population. However, the best place for recovery of a species is in the wild itself with a little better protection by the forest department, he said. “Captive breeding, and now conservation breeding, is an important tool, but only when we have understood that a particular species has declined to certain levels from where its population needs to be built with some assistance. It is also important to understand the reasons behind the decline in numbers so that that it can be corrected as well. So, first let us understand the status and distribution of the Bastar hill Mynahh before efforts are made to breed it in captivity,” he said.

New project to protect the species

Ratre, director of Kanger Valley National Park, informed that there is an adequate budget of approximately Rs. 40 lakh available with the forest department for the conservation of the Bastar hill Mynahh. A new project under this funding will be initiated under which, bird habitats in Kanger Valley will be surveyed and developed. The project was passed last year around October-November.

According to Ratre, CROW Foundation which has worked on the hill Mynahh has been roped in for the project. “There will be field visits in February. For the revival of the bird population, CROW Foundation has identified a few areas and camera traps will be set up inside Kanger Valley. After the field visits, it will be decided if captive breeding is feasible as it is a very shy bird. They may not breed if disturbed, as they have a specific choice of nests. So, we will have to see if we can go in for captive breeding or just protection and monitoring of nests,” the forest officer told Mongabay-India.

Ratre added that in-situ captive breeding is a good idea but efforts will be made so as not to bring the birds outside their natural habitats. “We can try in-situ breeding sites inside Kanger Valley where they can be in their natural surroundings. For herbivores, it is easy to breed them in captivity and release them, but for some birds it is a difficult thing.”

Mandavia agrees that the birds will not breed in captivity and under stress. “We want to assess the population. CROW Foundation has submitted a proposal where we have also talked about nest protection for the birds as well as planting of trees. The nesting season will start in April and May. When they do nest for breeding, it is the perfect time to give their nests protection. If the population has to be increased, the number of fruit-bearing trees will have to be increased too.”

Naidu informed that the parakeet is a tough competitor of the Bastar hill Mynahh. When both the male and female birds go out for food, in their absence parakeets occupy their nests made in holes. Naidu has made a design for 30 nesting holes for the birds in Kanger. These have to be monitored continuously. “If the birds choose even the nests, then our conservation plan will be successful. They are not getting an adequate number of woodpecker holes made in dry trees. Many sal trees are being cut down.”

Naidu spotted a flock of 22 birds between November-December 2020 and January 2021. His voice holds urgency when he says that if nothing is being done, the birds will vanish.

References:

india.mongabay.com