The 100th Meridian Initiative in Nevada: Assessing the westward movement of the Zebra mussel to the Lake Mead National Recreation Area

Abstract

Zebra mussels, Dreissena polymorpha, are a concern for all bodies of water in North America. East of the 100 Meridian, zebra mussels have infested the waters and dramatically changed the natural ecosystems. The US Fish and Wildlife Services set up the 100 Meridian Initiative project to monitor the boat traffic to and from infested and non-infested waters of the United States and Canada. Surveys were conducted from October 19, 2002 through March 31, 2003, focusing specifically on the Lake Mead National Recreation Area (LMNRA) for the scope of this thesis. This study addresses the movement of trailers, boats, and other watercraft that enter the LMNRA. Specifically, we addressed three items 1) the origin of trailers that come to the LMNRA, 2) the three previous boat launch sites (ex. Michigan, Idaho, and California) of boats launching at the LMNRA, and 3) the boat cleaning strategies of anglers, pleasure, jet skis, canoes, and other boaters. A total of 4739 trailers were surveyed with a total of 4152 (at 88%) from Nevada, California, and Arizona with a total of 587 (at 12%) from other recorded states; while a total of 177 contact interviews were performed. Descriptive statistics and Chi Square analysis were completed to test the differences from our expected results. A vast majority of the boats surveyed at LMNRA came from local states and non-infested waters; and pleasure boaters were identified as the subgroup of boaters who clean their boats more regularly. Based on the launch locations records of infested states, personal interviews, and cleaning practices the risk of zebra mussel transport to the LMNRA is low.