Myna birds are a common sight in many parts of the world, recognized for their bold and intelligent nature. Their adaptability has allowed them to thrive in a variety of environments, from bustling cities to quiet suburbs. This has led to a complex relationship with humans, who are often intrigued by their cleverness yet troubled by their ecological impact.
Identifying Myna Species
Two species of myna are most widely recognized: the Common Myna and the Hill Myna. The Common Myna (Acridotheres tristis) has a brown body contrasted by a glossy black head and neck. In flight, a distinct white patch becomes visible on each wing. This species possesses a prominent patch of featherless yellow skin directly below and behind the eye.
The Hill Myna (Gracula religiosa), often sought after in the pet trade for its vocal talents, presents a different appearance. It is covered in glossy black plumage that can show iridescent sheens of purple and green in the right light. Unlike its common relative, the Hill Myna has bright yellow wattles, which are fleshy lobes of skin, that extend from below the eye and up towards the back of its head.
Natural Habitat and Behavior
Originating in Asia, myna birds are found in open woodland environments and grasslands. They have long co-existed with humans, adapting to agricultural areas and the fringes of towns. Their success in these modified landscapes is partly due to their omnivorous diet, foraging on the ground for insects, fruits, grains, and nectar.
This adaptability means they readily consume food scraps left by people, making them a common fixture in urban settings. Socially, mynas are known for forming lifelong monogamous pairs that defend the same territory year after year. In the evenings, these birds exhibit a different social structure, gathering in large, often noisy communal roosts that can consist of hundreds or even thousands of individuals.
Vocalization and Mimicry
The vocal abilities of myna birds are extensive, encompassing a wide array of sounds like whistles, clicks, and squawks. This vocal dexterity is a hallmark of the family, but the Hill Myna is renowned for its mimicry. This species can replicate environmental sounds, including other birds’ calls and human speech, with remarkable clarity.
The biological basis for this ability is the structure of their syrinx, the avian vocal organ. The Hill Myna’s syrinx has highly developed and complex musculature, allowing for precise control over sound production. This enables the bird to modulate pitch, tone, and frequency to match the sounds it hears. While Common Mynas have a varied vocal range, they lack the capacity for clear mimicry of human speech that makes the Hill Myna famous.
Global Spread and Invasive Status
The Common Myna’s adaptability has facilitated its spread across the globe, establishing populations in Australia, South Africa, North America, and numerous oceanic islands. These introductions were sometimes intentional; for example, mynas were brought to Australia in the 1860s to control insect pests. However, their strong territorial instincts and aggressive behavior have had unintended consequences for native ecosystems.
As an invasive species, the Common Myna poses a significant threat to local wildlife. They aggressively compete with native birds for nesting cavities, often evicting other species, destroying their eggs, and killing their chicks. Their diet can also impact agriculture by damaging commercial fruit crops. Due to these impacts, the International Union for Conservation of Nature (IUCN) has listed the Common Myna as one of the world’s 100 worst invasive species.