While some animal rescue agencies collect animals from your home, not all of them offer this service. Whether or not they are able to do so also depends on the size and species of the animal.
For example, if you find a stray dog, your local dog warden may collect it from you to reunite it with its owner as soon as possible. If you find an injured animal, it is better to take it to your local veterinary clinic, as it may be in need of urgent medical care. If you are unable to care for or transport a found animal and your local rescue agency does not operate an emergency service, you may be asked to mark it's location on a map instead. Knowing the general location of the animal helps to make sure it is later collected and looked after.