The Use of Remote Sensing PIT Scanners for Monitoring Habitat Preferences Among Razorback Sucker at Imperial Ponds NWR

Authors: Jane S Fencl, Brian R. Kesner, Guillermo Ley, Paul C. Marsh

Year: 2010 (xlii)

Abstract

In April 2005, The Lower Colorado River Multi Species Conservation Plan (LCR-MSCP) was created to balance the use of water resources with conservation of native fishes, as a response to the continuing decline of native fish in the basin. A component of the plan was to develop off-channel locations focused on maintaining razorback sucker Xyrauchen texanus genetic stock. In 2007, six ponds were established at Imperial National Wildlife Refuge (INWR). In an effort to monitor razorback sucker habitat use, remote PIT (Passive Integrated Transponder) tag scanners were deployed throughout stocked ponds beginning in February 2009 on a monthly basis. The use of remote scanners has been integral in collecting data used to analyze habitat preferences and movement patterns throughout the year. Each month, four habitat types were randomly sampled for at least three consecutive days in each pond. Habitats were defined by specific features included in the design of the ponds and delineated as: hummock, rip-rap shore, mud shore, and open water. From February 2009 to September 2010, 3,476 PIT tag contacts were recorded at INWR. Habitat preferences varied among ponds and throughout the year. The ability to gather month-to-month movement and habitat use data at the individual and population level is unsurpassed by similar techniques such as camera trapping and fixed telemetry.