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OBJECTIVE 1 <br />APPROACH <br />Fish are being sampled using a combination of trot lines, drifted gill nets, stationary gill <br />net sets, trawls, and seines to sample sturgeon and associated species from as wide a range of <br />habitats as possible. Pallid sturgeon to be implanted with radio and sonic telemetry transmitters <br />are collected by netting or trot lines. Gill nets are drifted in areas along sand bars which have <br />been identified in current research (Snook 2001) to be important habitats for pallid sturgeon. <br />Benthic fish trawl tows are also used to sample deeper run and pool habitats for sturgeon and <br />associated species. Intensive sampling commenced in May 2001 and continued through August <br />at sites near Two Rivers, Ashland, Louisville, and Plattsmouth. Sampling resumed in April <br />2002. This coordinates with the larval fish sampling (objective 2). This period covers the time <br />when all sturgeon spawning takes place. All sturgeon captured are identified using aids such as <br />the Morphometric Character Index (Sheehan et al. 1999), measured (fork length) and weighed. <br />Samples of fin rays or barbels are being collected as voucher specimens for DNA analysis to <br />confirm Morphometric Character Index identifications. Sturgeon large enough to accept the <br />individual radio telemetry or combined radio and sonic telemetry tags are implanted in the field <br />and all sturgeon are tagged with PIT tags so that we can identify them if captured at a later date. <br />Attempts are being made to capture sturgeon which still have active transmitters by netting in <br />regions of the river where transmitter implanted fish are located and where transmitter implanted <br />fish have frequently been found in the past. <br />Radio and ultrasonic tagged fish are being monitored, throughout the year, from shore, <br />boat, and aircraft to determine their location. After each fish is located, a Global Positioning <br />3 <br />