Prior to European settlement, swamps, marshes, lakes, and streams were the major landscape features of the Chicago region. Much of this has been altered or lost in the past one-hundred-and-fifty years. We examined the changes in aquatic environments and fauna in Cook County, Illinois, using 1890–1910 and 1997–2017 as our focus intervals. The extents of aquatic features from historical topographic maps were imported into a GIS database and compared with the modern USGS National Hydrography Dataset. Historical and modern spatial data on aquatic animals were collected from museum collection and survey reports. Overall, the total area of wetlands and water bodies has decreased by about a third, while swamps and marshes have been drained or converted into lakes and ponds. Fifty-four of 80 historic molluscan species are not recently recorded, and 26 current species are not recorded in the historical data, including 6 considered to be invasive. Of 54 fish species in the historic data, 23 are no longer present and about 50% of the remaining species have undergone range reductions. Three out of 10 species of reptiles have disappeared. All 25 aquatic birds reported from the 1890–1910 period are still extant and an additional 13 have been reported in recent times, possibly due to increased collection effort. The Chicago region provides a case study of the impact of anthropogenic landscape change on biota. Large scale extirpations of native species have corresponded to a shift to a highly fragmented landscape of small ponds and reduced swamps and marshes.

在欧洲定居之前，沼泽，沼泽，湖泊和溪流是芝加哥地区的主要景观特征。在过去的一百五十年中，其中大部分已被更改或丢失。我们以1890-1910年和1997-2017年为研究重点，研究了伊利诺伊州库克县的水生环境和动物区系的变化。将历史地形图的水生特征范围导入GIS数据库，并与现代USGS国家水文数据集进行比较。从博物馆的收藏和调查报告中收集了有关水生动物的历史和现代空间数据。总体而言，湿地和水体的总面积减少了约三分之一，而沼泽和沼泽地被排干或转化为湖泊和池塘。最近没有记录80种历史软体动物中的54种，历史数据中没有记录26种当前物种，包括6种被认为具有入侵性的物种。在历史数据中的54种鱼类中，不再存在23种，剩余种类的约50％进行了范围缩小。每10种爬行动物中就有3种消失了。从1890年至1910年报告的所有25种水生鸟类仍在现存，近来又有13种已报告，这可能是由于增加了采集工作所致。芝加哥地区提供了人为景观变化对生物区系影响的案例研究。大规模灭绝本地物种对应于向高度分散的小池塘景观和减少的沼泽和沼泽转变。不再存在23种，剩余物种中约50％经历了范围缩小。每10种爬行动物中就有3种消失了。从1890年至1910年报告的所有25种水生鸟类仍在现存，近来又有13种已报告，这可能是由于增加了采集工作所致。芝加哥地区提供了人为景观变化对生物区系影响的案例研究。大规模灭绝本地物种对应于向高度分散的小池塘景观和减少的沼泽和沼泽转变。不再存在23种，剩余物种中约50％经历了范围缩小。每10种爬行动物中就有3种消失了。从1890年至1910年报告的所有25种水生鸟类仍在现存，近来又有13种已报告，这可能是由于增加了采集工作所致。芝加哥地区提供了人为景观变化对生物区系影响的案例研究。大规模灭绝本地物种对应于向高度分散的小池塘景观和减少的沼泽和沼泽转变。可能是由于增加了收集工作量。芝加哥地区提供了人为景观变化对生物区系影响的案例研究。大规模灭绝本地物种对应于向高度分散的小池塘景观和减少的沼泽和沼泽转变。可能是由于增加了收集工作量。芝加哥地区提供了人为景观变化对生物区系影响的案例研究。大规模灭绝本地物种对应于向高度分散的小池塘景观和减少的沼泽和沼泽转变。