Do you need to register animals when taking them with to Spain for 6 months?

My Self and Husband want to winter in spain, we want to rent for 6 months then we will move back to the uk. We dont need to work while we are there and want to bring with us pet dogs and birds. Is it as simple as driving to rented spanish house and getting on with it as if it were a long holiday or is there some hidden complications we should look into cheers sarah