Yes, TRUMPETERS is a Scrabble word!

Letter values in Scrabble US: T 1, R 1, U 1, M 3, P 3, E 1, T 1, E 1, R 1, S 1.

Is it a valid word?

TRUMPETERS is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

a musician who plays the trumpet or cornet
(formal) a person who announces important news
large gregarious crane-like bird of the forests of South America having glossy black plumage and a loud prolonged cry; easily domesticated
large pure white wild swan of western North America having a sonorous cry

Also: trumpeter swan, cygnus buccinator.