7908

• UCREFRP Catalog Number: 7908
• Author: Valdez, R. A. and R. J. Ryel.
• Title: Life History and Ecology of the Humpback Chub ‎(
• USFW Year: 1995.
• Copyright Material: NO

2-12 . Chapter 2

Marks
A Passive Integrated Transponder (PIT) tag was
injected into the intra-parietal cavity (Fig. 2-8) of
each humpback chub 175 mm TL and longer.
Starting in February 1991, minimum size of tagging
was reduced to 150 mm TL. External tags (i.e.,
Carlin or Floy tags) placed by previous investigators
were removed from native fish and replaced with
PIT tags with both tag numbers recorded. These old
tags were replaced at the request of the ACT
because PIT tags were considered more reliable; i.e.,
less chance of tag loss and greater capacity and
facility for information retrieval (Burdick and
Hamman 1993). PIT tags were also injected into
other native species (i.e., tlannelmouth suckers,
bluehead suckers) 150 mm TL or greater starting
August 1, 1991.

Beginning in January 1993, juvenile humpback chub
(range, 60-150 mm TL) were marked with
temporary fin punches (Fig. 2-9) to track
longitudinal dispersal. A 3-mm diameter biopsy
needle was used to punch various fin combinations
specific to river subreaches (Wydoski and Emery
1983). Various fin punch combinations were used
by BIW and AGF for juveniles captured and
released within respective subreaches of the
mainstem Colorado River (Table 2-3). Also fin clip
combinations were used by ASU for juveniles
captured and released at respective reaches of the
LCR

Final Report

B

j--I ""F01521
1- 4cm -I

~C
em

Fig. 2-8. Attachment sites for Carlin dangler tag (A)
and Floy anchor tag (B) by previous investigators,
and injection site for PIT tag (C) by this
investigation. Approximate fish length = 400 mm TL.

B

c

o

Fig. 2-9. Juvenile humpback chub with location of
scale samples (A), and punches of dorsal fin (B),
upper caudal fin lobe (C), and lower caudal fin lobe
(D). Approximate fish length = 75 mm TL.

Table 2-3. Fin punch combinations used by BIW and AGF to mark juvenile humpback chub in the mainstem
Colorado River, and fin clip combinations used by ASU to mark juveniles in the LCR.

Fin Punch Combinations (BIW, AGF) Location (Colorado River)

dorsal fin

lower caudal fin lobe

upper caudal fin lobe
dorsal fin plus upper caudal lobe
Fin Clip Combinations (ASU)
upper caudal lobe plus right pelvic fin
upper caudal lobe plus left pelVic fin
lower caudal lobe plus right pelvic fin
lower caudal lobe plus left pelvic fin

Malagosa Canyon to Lava Canyon (RM 57.6-65.4)
Lava Canyon to Hance Rapid (RM 65.4-76.6)
Hance Rapid to Havasu Creek (RM 76.6-156.7)
Havasu Creek to Diamond Creek (RM 156.7-225.7)

Location (LCR)
Chute Falls to Salt Trail Camp (RK 14.9-10.8)
SaltTrail Camp to Sipapu (RK 10.8-7.5)
Sipapu to Powell Canyon Camp (RK 7.5-3.0)
Powell Canyon Camp to Confluence (RK 3.0-0.0)