North Temperate Lakes LTER: Crayfish Abundance

Crayfish data include crayfish catch in cylindrical minnow traps baited with beef liver and occasional occurrence in other gear used to sample fish. Traps are placed at fyke net locations in nine study lakes (Allequash, Big Muskellunge, Crystal, Sparkling, Trout, Mendota, Monona, Wingra and Fish). Crayfish traps have been eliminated as gear in the Madison area lakes (Mendota, Monona, Wingra, and Fish) after 2003. Individuals are identified to species and counted. In Trout and Sparkling Lake more detailed surveys have been conducted during the summer on an ad hoc basis to track distribution and abundance of the invading species Orconectes rusticus. Additional data sets consist of pre-LTER sets (initiated in late June 1972) gathered by Capelli (Ph.D. dissertation) and Lorman (Ph.D. dissertation). Most of pre-LTER data is detailed distribution in Trout Lake, and community composition in other area lakes. Sampling Frequency: annually Number of sites: 9本螯虾（crayfish）数据集涵盖了使用以牛肝为诱饵的圆柱形小鱼陷阱捕获的螯虾样本，以及在其他鱼类采样渔具中的偶获记录。此类螯虾陷阱布设于9个研究湖泊（Allequash湖、Big Muskellunge湖、Crystal湖、Sparkling湖、Trout湖、Mendota湖、Monona湖、Wingra湖与Fish湖）的袋网（fyke net）采样点位处。2003年后，麦迪逊区域内的Mendota湖、Monona湖、Wingra湖及Fish湖已停用螯虾陷阱作为采样渔具。所有捕获个体均会被鉴定至物种水平并完成计数。针对Trout湖与Sparkling湖，科研人员已于夏季开展临时专项调查，以追踪入侵物种锈色螯虾（Orconectes rusticus）的分布与种群丰度。额外数据集包含由Capelli（博士学位论文）与Lorman（博士学位论文）所收集的长期生态研究（LTER）前期采样序列，该序列于1972年6月下旬启动。其中多数LTER前期数据涵盖了Trout湖的详细分布调查结果，以及其他周边湖泊的群落组成信息。采样频率：每年1次；采样点位总数：9个