Coyotes howl for several reasons, including communication and territorial marking. Here are some key points about coyote howling:

• Coyotes howl to call their pack back together after a period of individual hunting.
• They also howl to advertise their presence to other packs and warn them against trespassing across territorial boundaries.
• Coyotes can differentiate among the coyotes in their group by their howls, so they also know when a howl is coming from a coyote that is not a part of their pack.
• Howling can also serve to bring members of a pack together and coordinate hunting efforts.
• Coyotes may bark when they are defending a den or a kill.
• If the howling is interspersed with barking, its usually indicative of a disturbance or agitation, such as a perceived threat due to an intrusion on marked territory.
• Coyotes howl and yip primarily to communicate with each other and establish territory.
• Coyotes can make a lot of noise, particularly at night, but there is no evidence that they howl at the moon.

Overall, coyote howling is a basic communication behavior that serves several functions, including calling the pack back together, advertising their presence, and establishing territory. If you hear coyotes howling, there is generally no need for alarm unless the animals are showing aggressive behavior towards humans or pets.