8171

• UCREFRP Catalog Number: 8171
• Author: U.S. Fish and Wildlife Service.
• Title: A Study to Determine the Biological Feasibility of Pit Tags for Endangered Fishes in the Upper Colorado River Basin.
• USFW Year: 1990.
• USFW - Doc Type: Grand Junction, Colorado.
• Copyright Material: NO

1

1
s

1
11

Of the two PIT-tagged (body cavity) roundtail chub captured on day 430, one had
been previously captured on day 351 and both had been captured on day 343. It is
possible these few fish were highly susceptible to recapture, or that very few fish
remained in the ponds.
13th-hole Pond. Twenty-five fish each were established for the control and test
groups during July 1988. Some fish died after handling and tagging and prior to release
(2 controls, 7 PIT tagged in the body cavity, 3 PIT tagged in the dorsal musculature).
Long-term survival of fish in this pond was also low. On day 114, only 14 fish were
recaptured: 6 controls, 3 PIT tagged in the body cavity, and 5 in the dorsal musculature.
On days 296 and 360, 14 and 11 fish were recaptured, respectively. We were confident
that we were effective in capturing most of the fish from 13th-hole Pond because 88%
and 8601o of fish in the two test groups captured on days 296 and 360, respectively (Table 1),
had been recaptured previously. We did not recapture any roundtail chub on day 437.
Colorado squawfish
west pond. Twenty fish for each of the groups were established 30 September
1988. We were ineffective in recapturing fish from the control and test groups from this
of these fish were of the control or test groups.
pond, also. On day 212, we captured 36 Colorado squawfish by angling. However, none
On day 310, West Pond was treated with rotenone. A total of 330 Colorado
squawfish was recovered. However, we recovered only 12 (20%) of the original 60 fish
released from the control and two test groups. These included 5 controls, and 7
15