Experimental midwater horizontal longline and vertical longline data collected during a NOAA R/V Townsend Cromwell cruise in 1989 at the SE Hancock Seamount

Midwater longline operations were fished both in a horizontal (targeting a particular depth stratum) and vertical manner over the seamount summit and slopes. All midwater longline operations were conducted at night. For midwater horizontal longline operations, gear was set to fish within scattering layers over the summit and upper slopes. Because of difficulty in minimizing the amount of sag in the main line and the lack of catch, the midwater horizontal longline gear was modified and fished as a vertical longline. Each vertical longline set consisted of two to three vertical strings.