“The video was shot in ‘Wolfspark Werner Freund’ where visitors can see different wolf packs (Arctic, European Grey, and Timber wolves) and listen to the packs howl in chorus.
Wolves howl for a variety of reasons. Pack members will chorus howl to defend their territory and rally the pack together. Most howls heard in the pack are chorus howls (involving three or more wolves).
These group “sing-a-longs” may be started by any pack member, or they may be a response to the howling of a neighboring pack of wolves or a coyote. Wolves will even howl in response to something that just sounds similar to a howl, like a train whistle, fire or police car siren or even a human howling!