7381 - Laserfiche WebLink

Home Browse Search

. ME'l1DX)LQGY . . This investigation consisted of two work phases. phase one involved the capture and implantation of radiotransmitters into 10 adult Colorado squawfish and 10 adult razorback suckers. phase two consisted of radiotracking the fish over a 5-month winter period. phase one was conducted in two 10-day periods during October 9-31, 1986, and phase two was conducted dJdfing ~ 10-da..Y periods from December 12, 1986, thro~h March 31, 1987 (Table 1). Equipoent . Two basic sets of equipment were used during this investigation including electrofishing gear and radiotelemetry equipment. A brief description of each is presented below. . Two 16-foot jonboats, one 14-foot jonboat and two motorized Riken Havasu hypolon rafts, 17 and 18 foot, were used during the course of the study. The 18-foot Havasu was powered by an XD-25 hp Mercury outboard and used as an electrofishing boat in the whitewater portions of the study area during the first phase of the project. The 17-foot Havasu, powered by a 9.9 hp Mercury outboard was used as a support craft during electrofishing in whi tewater sections. . During the first phase of study, the 16-foot jonboats, powered by XD-25 hp Mercury motors, were used as electrofishing craft as described later in this document. During the second phase of the project, the two 16-foot jonboats, powered primarily by 35 hp and 20 hp Mercury outboards, were used to locate and take habitat measurements on radiotagged fish. The 14-foot jonboat and a 9.9 hp Mercury outboard were taken into Echo Park and stored there from November through March for local use in locating radiotagged fish and taking measurements on navigable waters in the Echo and Mitten Park area. . . Electrofishing. Electrofishing was used to capture adult Colorado squawfish and razorback suckers for implantation of radiotransmitters. Electrofishing was conducted during two field trips in October (Table 1). Shockinq was primarily dOIle alonq shorelines 2!: other suitable l1abitat accessible by boat. A 220-vol t DC system was used from each of the three different boats described above. The systems were powered by either a 4.5- kilowatt EMS Honda generator or a 3. 5-kilowatt Homeli te generator and controlled by one of two Coffelt VVP-15 variable voltage pulsators capable of amplifying the output to 600 volts. The normal operating level was 90-200 volts and 4-10 amps. . . One or two netters dipped the fish from the bow of the boats. Actual electrofishing ti I1\P. in seconds was monitored for all efforts and used !.D c~lculating catch per unit effort (CPE) as number of fish per 10 hours. Adult squawfish ana razorback suckers were held in live wells for transport back to camp. Data from electrofishing runs, including all pertinent data on target species, were recorded on field data sheets provided by FWS. Numbers of other species of fish were counted or estimated by netters and recorded. 5 . ~o...~o... co-'" .,..\ '1ot .....t..J 0..$ S",l,Itn...lt" t.~.~tl!.l ... ....0 \- \'" t".(tft- ck ,,~t-