Sir, Poole (Animal Welfare 1992, 1: 203-220) argues that mammals are unique in having behavioural needs, that is, in experiencing a need to carry out behaviour that is not necessary for immediate survival. While I very much welcome the stress his article places on good welfare being much more than just the satisfaction of health and survival needs, I am also concerned that he may have done a disservice to non-mammalian species by implying that none of them have behavioural needs comparable to those of mammals. He acknowledges that birds are intelligent and have considerable learning abilities but then argues that this does not imply the existence of behavioural needs. On what grounds, then, does he attribute such needs to mammals and not to birds?