Creel fisheries, using fleets of baited pots or ‘creels’ to catch Nephrops, lobsters and crabs, are an important component of the inshore, and to a lesser extent offshore, Scottish fishing sector. Unfortunately, this fishery has also been implicated in accidental lethal entanglements of marine mammals and other megafauna, notably minke whales, humpback whales and basking sharks. It is not clear how much of this impact is caused by creel fishing gears (fleets) that are actively fishing and regularly tended, vs. fleets that have been lost due to storms or interactions with other fishers. Loss rates of creels are poorly characterised but anecdotal records suggest they may be considerable. To address ongoing impacts of creel fisheries on species of conservation concern in Scotland, it is essential to understand the distribution and configuration of, and risks posed by, derelict creel fleets. The CreelMap project sought to evaluate a combination of different towed side-scan sonar (SSS) systems and in-situ observations by Remotely Operated Vehicle (ROV) to assess whether these tools can efficiently detect and locate derelict creel fleets, an essential first step towards considering potential recovery.