The Hungry Animals mod gives animals in Minecraft a more realistic tone. They are naturally more afraid of you and other people so taming must be practiced carefully or by use of traps. You’ll see a meter when you hover your pointer over an animal and that explains the health, hunger, and tamability of them. They will also feed and reproduce on their own.
Animals now have the capability to survive on their own. They will find their own food or risk possibly starving. They will also find a mate naturally and nature just finds a way. Everything maintains balance with or without your interaction.
The bottom meter is the one to pay attention to when taming these animals. It will range from red to green, red being wild and green being tamed. The traps aren’t meant to harm the animals but are meant to be a means to get close to them without them running away. Once you spend enough time around these animals, you’ll then be able to tame them.