They arrived earlier than that. I took a photo of one in this enclosure in April 2013 (so it's quite a long way back in this Gallery).
There are quite a few of them around. I have seen them at Newquay and Shaldon too.
My experience of this species at the two above mentioned collections is they are a pain in the backside to photograph with a standard camera. The hyperactivity of them meant all of my photo's came out very blurry indeed!