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
Bird reserve Habitat) is an international agreement to protect wetlands, with special focus on aquatic birds. In Sweden it is the County administrative boards of Sweden and the Environmental Protection Agency that selects which areas are to be designated as bird reserves. Among the noted areas are Tåkern, Lake Hornborga, the southern part of Öland and Getterön. There are approximately 50 Ramsar areas in Sweden, and around 530 SPA areas where the latter comprises almost . Bird reserve A bird reserve (also called ornithological reserve) is a wildlife refuge designed to protect bird species. Like other wildlife refuges, the main goal of