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
at Hotchkiss NFH is ongoing and these fish will be maintained and monitored through
I July 1990.

1

1
Grand Junction. This was a feasibility study to determine if juvenile fish could be
successfully cultured at our station complex in Grand Junction. If successful, additional
on-station facilities might be installed to accommodate more fish. These would include
larger recirculating tanks. These additional facilities would allow evaluation of PIT-tag
performance for several age classes of Colorado squawfish and razorback sucker.
Twenty fish each for the control and one test group were established 15 June 1989.
However, all of these fish died three weeks later when water temperatures rose to 27 C.
Mid-day air temperatures were 38-41 C and we were unable to control the water
temperature in the holding tanks with the available water supply. This portion of the
study was abandoned.
SUMMARY AND CONCLUSIONS

1
1

1
1
t
1. PIT tags were implanted in adult-size roundtail chub, two sizes of juvenile
Colorado squawfish and juvenile-size razorback sucker. PIT tags were
implanted into two anatomical sites, the body cavity and dorsal musculature.
2. Plans to implant and evaluate the performance of PIT tags in adult-size
Colorado squawfish and razorback sucker brood fish held at Dexter NFH did
not materialize. However, 164 adult-size Colorado squawfish and 527 juvenile-
and adult-size razorback sucker were PIT tagged in September 1989 at Dexter
NFH. These fish will be monitored and the performance of the PIT tag
23