8086

• UCREFRP Catalog Number: 8086
• Author: Valdez, R. A. and B. R. Cowdell.
• Title: Lake Powell Inflow Study. Annual Summary Report - 1993.
• USFW Year: 1994.
• USFW - Doc Type: 384-1,
• Copyright Material: NO

Table 4. Pooled catch per effort (CPE) by species for electrofishing, Lake Powell inflow, 1993.
Species N1 Age-O JUV ADU TOTAL CPE (No./I0 hr)
CP 33 0 3 416 419 451.25
CC 28 8 61 33 102 109.85
WE 9 0 0 15 15 16.15
CS 5 0 4 5 7 7.54
SB 5 0 0 7 7 7.54
BH 1 0 2 0 2 2.15
BC 1 0 0 1 1 1.08
GS 1 0 0 1 1 1.08

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4.2 FISH COLLECTIONS BY GEAR TYPE WITH CPE STATISTICS

A summary of sampling effort by gear type is presented in Table 3. Summaries of fish species collected by life
stage and associated CPE for each gear type are presented in Tables 4 - 7. All CPE statistics reported in this
section were computed using the pooled CPE method.

Table 3. Summary of fish sampling efforts (number of efforts and total time) for Lake Powell inflow
sampling 1993.

GEAR PRE-RUNOFF POST-RUNOFF
Electrofishing -EL 16 (5.8 hrs) 20 (3.5 hrs)
Gill Net - GP 7 (14 hrs) 0
-
Trammel Net - TK 24 (48 hrs) 0
Seine - SE 32 32
Larval Light Trap - L T1 0 30 (265.2 hrs)

1_ Larval light traps were used on a separate NPS sampling trip in the Lake Powell inflow on June 20-21,
1993. Twenty traps were set for a total of 169.0 hrs.

4.2.1 Electrofishin2

Catch rate information for electrofishing was pooled for the two trips because species composition and catch
rates were similar. The highest catch rates with electro fishing gear were for carp (451.25 fish/lO hr) and
channel catfish (109.85). Pooled CPE for Colorado squawfish was 7.54 fish/lO hr. Catch rates for large
predatory fish, walleye and striped bass, were 16.15 and 7.54 fish/ 10 hr respectively.

Numerous age-O threadfin shad were noted during post-runoff electro fishing. Due to the large number and
their small size, no attempt was made to capture these fish.

I-Number of samples with indicated species (36 samples total)

8