The Ohawk were a pre-warp species native to the planet Man-us II. They were known to be hostile to visitors.
While he was in command of the USS Enterprise in the 2240s, Captain Robert April landed on Man'us II without his security officer. The ensuing events led to his revealing the Enterprise to the Ohawk, in violation of the Prime Directive.
During Una Chin-Riley's court martial in 2259, Neera Ketoul cited the Ohawk incident as an example of when a Starfleet captain had exercised their judgment over the application of law for the greater good. (SNW: "Ad Astra per Aspera")