9636

• UCREFRP Catalog Number: 9636
• Author: Marsh, P. C.
• Title: Spatial and Temporal Aspects of Bonytail Chub Movement and Habitat Use, Cibola High Levee Pond, Lower Colorado River, Arizona and California, 2003-2004.
• USFW Year: n.d.
• USFW - Doc Type: Tempe, AZ.
• Copyright Material: NO

sorted by time periods designated as dusk (1945 to 2200), mid-hours (2215 to
0315), and dawn (0330 to 0545), and by fish pulse code number.
Point Data Analysis. During the course of study in 2003 it was discovered that at
times some signals originated from within the interstices of the large material
used to construct the high levee. It was presumed that individual signals were
associated with individual fish. The high levee thus was divided into 26, 5 m
wide "zones," consecutively designated with alpha characters A through Z.
Signal detections and fish locations were referenced and recorded by zone.
Point data were entered into atwo-way spatial distribution table that represented
the number of times each fish was observed within each zone of the high levee.
The table was used to create a histogram for each fish that depicted the number
of times it was contacted within each zone, and a cumulative histogram was
constructed that showed the total number of contacts within each zone for all fish
combined. A two-way goodness-of-fit test using the Pearson Chi-square statistic
(Sokal and Rohlf 1995) was performed for nonrandom association of specific fish
with a specific zone(s) to determine if there was any fidelity to a particular zone,
or if fish simply were found at random among the 26 zones.
2004 Data Evaluation. Point data were plotted on an area map of Cibola HLP to
show known locations and presumed fate of individual fish.
Results and Discussion
Bonytail tagged in 2003 (n=10) ranged in total length from 404 to 514 mm with a
mean of 453 (Table 1). Fish from 2004 (n = 9) were smaller; 250 to 301 mm long
with mean of 284 mm and weight of 101 to 159 g with a mean of 138 g (Table 2).
Tracking during 2003 was conducted for up to four days each week from release
of fish on 19 March to end of the experiment on 07 May. These large bonytail
showed a strong tendency during daylight hours to occupy the interstices of the
large material-that was used to construct the high levee, and visited the open
water of the Cibola HLP almost exclusively during darkness. In fact, there was
virtually no evidence that any fish utilized open water during daylight. Our initial
failure during daylight to detect signals using a directional hydrophone anywhere
in the pond a week after fish were tagged and released resulted in a point search
using the omni-directional probe. Discovery of fish using the interstices of the
high levee was serendipitous and quite a surprise.
Point Data. A total of 32 point surveys of the high levee were performed: 16 in
the morning and 16 in the evening. The number of contacts per fish ranged from
26 to 32, signals were encountered at 19 of the 26 designated zones, and total
number of contacts (all fish combined) per zone ranged from 1 to 63 (Table 3).