You can tell if a hamster is hungry through various means such as observing its behavior, sounds, and the condition of its food bowl.
Behavior Observation
When a hamster is hungry, it will show signs of restlessness. It will keep pacing around the cage, and may even use its tiny paws to scratch at the cage, as if telling you it's hungry. They might become unusually active, jumping up and down or following their owner around, showing great interest and anticipation.
Sound Changes
A hungry hamster may make a hissing sound or emit faint squeaks. These are signals that it's sending out to let you know it's hungry.
Food Bowl Check
If you find that the hamster's food bowl is completely empty or only has a few crumbs left, it means the hamster is hungry. Additionally, the hamster may use its paws to scratch at the food bowl, making a rustling sound, indicating that it needs food.
Other Behaviors
When hungry, hamsters will also keep sniffing around, as if searching for the smell of food. Some hamsters may lick or chew on the cage. This is not only for teeth - grinding purposes but could also be due to hunger.
By paying attention to these changes in behavior and sounds, you can effectively determine whether a hamster is hungry and promptly provide it with an appropriate amount of food.