Several designs of seal exclusion devices (SEDs) were tested to reduce bycatch of seals in the winter blue grenadier trawl fishery. A 'top-hatch' SED, or one with a top-mounted escape hatch, resulted in the lowest occurrence of seal bycatch than any other SED design or than nets without a SED. The SED prevented entry into the net codend where drownings occurred. They also successfully expelled seals and limited access into the net via the escape hatch. Cameras are needed to verify the results.