Dogs are territorial beasts and will do whatever it takes to protect the place they call home.
Most dogs bark when they need love. The easiest way to tell is if it’s looking you in the eyes when it’s barking—all it needs is some attention to feel wanted.
Dogs were pack animals in the wild and still carry those needs as domesticated pets. In a home without other dogs, you are the pack leader. When their leader ignores them, barking is the only way to get closer to him.
A canine that is injured or hurt will bark a lot. It’s the only way to let you know it’s in pain and needs help. Barking becomes even more critical if you are in a different room, and being loud is the only way you will notice.
Aging pets will wander around your home looking lost and barking loudly because they are confused.