Wildlife, including birds and other animals can sometimes be protected, such as bats, and it is illegal to disturb any nest in the wild. However, even the RSPB will acknowledge that it is sometime beyond a gardener or homeowner’s capability to ignore damage caused by wild creatures. The purpose here to attempt to deter said creatures, not to actually harm them.Do bear in mind that no method is perfect. For example, if you want to attract certain birds like tits or robins, you will have to accept that you may end up with green parakeets and the like as well. Some animals need to be kept out of your garden. For example if you have a pond, you don’t want herons picking out your fish, if you keep rabbits, foxes will not be welcome and so on. Many people loathe sparrowhawks and starlings, usually because they are a nuisance.
Do be aware that there are many visual and audible deterrents for use on farmland and other open space situations away from housing. These are not suitable for domestic use in the most part. They are also not species specific so be wary of using them. It is usually perfectly legal to deter birds but the bird must not be harmed or trapped, nor can they be prevented from attending to an existing nest. If you plan to deter birds, make sure they have elsewhere to go otherwise all you will do is upset and distress them.
Herons can be discouraged form ponds by installing a specialist pond cover which will also protect children and pets from drowning. Foxes can be discouraged by ensuring no food scraps are available, nowhere cosy can be taken over for nesting and sleeping, and a good solid fence is installed with no stepping places for the fox to climb over easily.