WELLINGTON, Jan. 9 (Xinhua) -- Soaring summer temperatures in New Zealand's South Island are causing concern for penguin rescuers.

The Christchurch Penguin Rehabilitation Center said on Wednesday that between November 2017 and May last year it looked after 40 penguins.

But already so far this season, 11 have been either injured or starving, the center said, adding the hot weather was to be blamed.

The center's spokesperson Kristina Schutt said high temperatures made it harder for penguins to find food, because the fish they usually caught swam in deeper waters when it was hot.

Yellow-eyed, little blue and white-flippered penguins were often found in distress, Schutt said.