i Register
In some senses, balker is marked as obsolete. Watch for register when choosing this word.
noun
Someone or something that balks; a naysayer.
A person who stands on a rock or eminence to observe shoals of herring, etc., and to give notice to the men in boats which way they pass.
The Pilcherd are pursued and deuoured by a bigger kinde of fish, called a Plusher, being somewhat like the Dog-fish, who leapeth now and then aboue water, and therethrough bewrayeth them to the Balker […]
“Ye are caught, master wizard,” cried Fleetwood, laughing; “the balkers have marked their fish, and we hold you as our prize.[”]