Aggressive behavior in dogs can stem from various factors such as fear, territorial behavior, lack of socialization, and even genetics. However, with proper training, it’s possible to modify aggressive behavior in your Beagle. Here are some steps you can follow:

1. Consult a professional – If your Beagle’s aggressive behavior is severe, it’s best to consult a professional dog behaviorist. They will be able to assess the root cause of your dog’s aggression and provide personalized training recommendations.
2. Provide socialization – Socialization is the process of exposing your dog to different people, animals, and environments to build their confidence and reduce their fear. A well-socialized dog is less likely to display aggressive behavior.
3. Use positive reinforcement training – Reward your dog for good behavior, such as obedience and socialization, with treats, praise, and attention. This will encourage your dog to repeat positive behaviors and discourage aggressive behavior.
4. Avoid punishment – Punishing your dog for aggressive behavior can make the situation worse by causing fear or anxiety in your dog. This can lead to an increase in aggressive behavior.
5. Implement a consistent routine – Providing a consistent routine can help reduce your Beagle’s anxiety and reduce the likelihood of aggressive behavior. Establishing a routine can include feeding, walking, and play times at the same time every day.
6. Provide plenty of physical and mental stimulation – A bored or frustrated dog is more likely to display aggressive behavior. To prevent this, make sure your dog has plenty of physical and mental stimulation through activities such as exercise, training, and interactive toys.
7. Address fear and anxiety – Fear and anxiety can often lead to aggressive behavior. Identifying and addressing the cause of your Beagle’s fear and anxiety can help reduce their aggressive behavior.
8. Be consistent – Consistency is key when it comes to modifying aggressive behavior. It’s important to use the same commands and techniques every time, and to provide consistent rewards for good behavior.

Modifying aggressive behavior in your Beagle takes patience, consistency, and a commitment to training. However, by following these steps, you can help your dog become a well-behaved, confident, and happy companion.