Board Thread:WARNING ALL USERS False Info\Spoilers/@comment-108.81.117.0-20130922203715/@comment-6207588-20130922210328

^at the end of season 2 Peter told Isaac that the reason Derek was in such a hurry to build his pack was because the alpha pack was coming...Jackson was the first one Derek tried to turn...he was already building the pack before Jackson manifested as the Kanima...so Derek already knew they were on their way when he began turning people.

Personally I think they heard there was a Hale alpha and came because Deucalion has a history with Talia and the Hales and wanted to procure a Hale alpha for his collection. It could have been Peter they even heard about and by the time they got there Derek was alpha...wouldn't matter...it was still a Hale alpha...but that's just speculation on my part.