Estimates of recreational fishing effort and catch are needed to inform fisheries management, but such estimates can be challenging to obtain. We combined a zig-zag line transect survey of buoys, a fisheries enforcement survey and a drone survey to estimate recreational effort in the open-access trap fishery for signal crayfish (Pacifastacus leniusculus) in the sixth largest lake in Europe, Lake Vättern, Sweden. Using supporting variables such as size of nearby ports and bathymetry, our model-assisted estimate of total effort was 6400 (±4300 CI) buoys during the three-weekend season. Using the frequency of buoys to traps as a constant, the total number of crayfish traps was estimated to be 25,500 (±17,000 CI). The sampling design and methods presented are useful for ecologists and resource managers to design future multi-source surveys of recreational trap fishing effort.

中文翻译：

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通过锯齿线样线、无人机调查和执法调查估算小龙虾的休闲诱捕量

需要对休闲捕捞努力量和渔获量进行估算，以便为渔业管理提供信息，但获得此类估算可能具有挑战性。我们结合了浮标的锯齿形线横断面调查、渔业执法调查和无人机调查，以估算欧洲第六大湖瑞典韦特恩湖开放式诱捕渔业中信号小龙虾（ Pacifastacus leniusculus ）的休闲努力。 。使用附近港口的大小和测深等支持变量，我们的模型辅助估计在三个周末的季节中总工作量为 6400 (±4300 CI) 个浮标。使用浮标到陷阱的频率作为常数，小龙虾陷阱的总数估计为 25,500 个 (±17,000 CI)。所提出的抽样设计和方法对于生态学家和资源管理者设计未来的休闲诱捕捕捞努力的多源调查很有用。