Common pochard and small populations are sometimes observed on the River Thames. Large numbers stay overwinter in Great Britain, after the birds retreat from Russia and Scandinavia. These are gregarious birds, forming large flocks in winter, often mixed with other diving ducks such as the tufted duck, with which they are known to hybridise. These birds feed mainly by diving or dabbling. They eat aquatic plants with some molluscs, aquatic insects and small fish. They often feed at night, and will up-end for food as well as the more characteristic diving. In number of countries the population of Common Pochard is decreasing
Bird netting of a barrier to their diving into the ponds. Bird netting is one of the most effective and long lasting ways of bird proofing buildings and other structures against all urban bird species. It provides a discreet and impenetrable barrier that protects premises without harming the birds. Bird netting can be particularly effective for large open areas such as roofs and loading bays. Design considerations include the type and material of the fixings utilized and the bird species requiring exclusion. Miners will use chemical agents to extract minerals or metals from crushed rocks. These harmful chemical agents must be confined