Black bird with white moustache

Hi

When we visited the Sealife centre at Hunstanton either 14th or 15th August this year, my sister and I saw 5 black birds having orange legs and beeks plus white curled feathers near the eyes in with the penguins at the 3 o'clock feeding time. Ive been trying ever since to find out what the birds were and it wasn't until my daughter added "moustache" to the description that a photo came up on the internet.  I think that they were as the attached picture.  Has anyone else reported having seen them?