The thick-billed murre or Brünnich's guillemot (Uria lomvia) is a bird in the aukfamily (Alcidae). This bird is named after the Danish zoologist Morten Thrane Brünnich. The very deeply black North PacificsubspeciesUria lomvia arra is also called Pallas' murre after its describer. Murres have the highest flight cost, for their body size, of any animal.