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.~ . VIDE 0 GRAPHY Methods Spawning activities and fish behavior were recorded using a black and white underwater video camera and VHS recorder. The video system consisted of both underwater and surface components. A camera head the size of a soda can was attached to a small bipod fixed to the end of a 3-m piece of steel conduit. We discovered that bonytail avoided visible artificial light, so an infrared spot light (300 W infrared-880 !lm) was attached next to the camera for illumination at night. This equipment was wired to a monitor, a VHS recorder, and a 12-V DC battery that powered the system (Photo 4). Photo 4. Video camera monitor, recorder, and power source set-up on the CHLP river levee. The camera was aimed by simply turning the system on, lowering it into the water and positioning it using the conduit from shore. Monitoring sessions contained varying proportions of substrate and water column. The viewing area varied due to camera angle, turbidity, and lighting. During daylight hours we could see fish clearly for 1-2 m but at night this distance was often reduced to <30 em. The relative size of the monitoring area was estimated based on the average size of razorback sucker (50-em) fu'1d tadpoles (75- mm) seen in the frames. Monitoring areas fell into four size categories: 30 X 30 em, 45 X 45 em, 60 X 60 em, and 90 X 90 em. The camera was set-up in one of three general locations: 1) the deep portion of the pond offthe river levee where razorback were spawning, 2) the area where bonytail spawned the past two years, and 3) at two control sites where spawning had not been observed nor suspected, at the toe of the high levee and at a portion of undisturbed river levee. Underwater activity was recorded on 2-hour VHS videocassette tapes. 7