Effective control of aquatic invasive species requires knowledge of the population throughout the infested area. Lake-wide assessments of invasive sea lampreys (Petromyzon marinus) are used to assess their status in the Laurentian Great Lakes, informing fisheries managers and decision makers in the sea lamprey control program. Initially these assessments focused on an estimate of absolute abundance, but later switched to an estimate of relative abundance as an index. In this paper, we describe the recently developed index of sea lamprey abundance and the reasons for its use. Rather than trying to estimate spawning run sizes of all Great Lakes tributaries, the index instead estimates run sizes of a small subset of index streams. Streams chosen for the index had large spawning runs and a history of trapping operations that consistently yielded mark-recapture estimates. This change enabled the sea lamprey control program to abandon a previously used regression model that predicted run size on streams with no sea lamprey traps. Further research is needed to determine how strongly correlated the index is with actual patterns in the lake-wide population of adult sea lampreys.

有效控制水生入侵物种需要了解整个受灾地区的种群情况。全湖性侵袭性海鳗的评估（Petromyzon marinus）用于评估其在劳伦大湖中的地位，并在南lamp鳗控制计划中告知渔业经理和决策者。最初，这些评估着重于绝对丰度的估计，但后来转向相对丰度的估计作为指标。在本文中，我们描述了最近开发的海七lamp鳗丰度指数及其使用原因。索引不是尝试估算所有大湖支流的产卵游程大小，而是估算一小部分索引流的游程大小。为该索引选择的流具有较大的生成运行时间，并且具有捕获操作的历史，这些捕获操作始终产生标记捕获的估计值。这项更改使Sea Lamprey控制程序可以放弃以前使用的回归模型，该模型可以预测没有Sea Lamprey捕集阱的河流的游程大小。