The agency won the £2 million business after a pitch against undisclosed agencies. Initiative, the incumbent, did not repitch for the account. Targeted campaigns will roll out in March.
The win comes as London Zoo gears up for its new exhibit, Tiger Territory, which will open in spring 2013.
Rich Storton, the commercial and communications director at the ZSL, said: "Arena Media’s creativity and digital expertise shone out for us at the pitching stage. We were very impressed with their understanding of our business and their enthusiasm for our brands."
Chris Armond, the group business director at Arena Media, said: "This is a really exciting time to be taking on the account, and we’ll be working to engage family audiences across traditional and digital media."