Dunnock relatively lower success for females. In times of scarcity, female territories expand to accommodate the lack of resources, causing males to have a more difficult time monopolizing females. Hence, females gain a reproductive advantage over males in this case. The dunnock possesses variable mating systems. Females are often polyandrous, breeding with two or more males at once, which is quite rare among birds. This multiple mating system leads to the development of sperm competition amongst the male suitors. DNA fingerprinting has shown that chicks within a brood often have different fathers, depending on the success of the males at monopolising
Common myna the predominant bird in urban areas all along the East coast. In a 2008 popular vote, the bird was named "The Most Important Pest/Problem" in Australia, also earning the nickname "flying rats" due to their scavenging resembling that of rats. It is also known as "the cane toad of the sky". The common myna was first introduced to Australia in Victoria between 1863 and 1872 into Melbourne’s market gardens to control insects. The bird is likely to have spread to New South Wales (where it is currently most populous) at around the same time, but documentation is uncertain. The bird