WSP11129

• File Number: 8460.400
• Description: Platte River Basin-Platte River Basin Endangered Species Issues-Platte River Management Joint Study
• Basin: South Platte
• Water Division: 1
• Date: 6/26/1992
• Title: Report for Tasks 4 and 5
• Water Supply Pro - Doc Type: Report/Study

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Whooping Crane Roosting Habitat Suitability Indices

(a)

(b)

Unobstructed Channel WIdth
at W Crane Roost SItes
on the Platte RIVer

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Unobstructed Channel WIdth (ft)

400 800 1200
Channel Width (ft)

(d)

(c)
Channel Wldths
m the Central Platte
ca.n:.: PWlIaD.., 8tadyJ

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Preference FunctlDn for
Unobstructed Channel WIdths
Used by Whooping Cranes
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300 600 700 9DO 1100
Max Channel Width (ft) PWlI'"'

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D.CIl7C11901:1ttl101300
Unobstructed Channel WIdth (ft)

Figure A1. The SI curve for channel width (a) was developed based on
available data and expert opinion. Channel width data was collected
at 23 roost sites from 1983-1991 (b). A Type III preference index
for channel width (d) was constructed by computing the ratio of use
(b) to availability (c) for each width class (Bovee 1986). The
database of available channel widths was from the Service's Platte
River Ecology Study (1981). This database reported only the widest
channel in each 1/2 mile river segment. As a result, preference is
probably somewhat overestimated for the 300-500 foot width class, and
severely overestimated for the 100-300 foot width class.