7.—(1) The National Assembly must carry out surveillance at such premises and of such birds as it considers necessary—
(a)to detect the prevalence in different species of poultry of infection with avian influenza virus subtypes H5 and H7; and
(b)to assess the risk of the spread of influenza of avian origin by wild birds.
(2) The National Assembly must give notice to the occupier of premises selected by it for the purposes of such a survey.