9425

• UCREFRP Catalog Number: 9425
• Author: Bezzerides, N. and K. Bestgen.
• Title: Status Review of Roundtail Chub
• USFW Year: 2002.
• Copyright Material: NO

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Natural History, and from the Arizona Fish and Game Department (AGED unpublished),
the Wyoming Game and Fish Department (WGFD unpublished), Wyoming Natural
Diversity Database, and Utah Division of Wildlife Resources (LIDWR 2000b and
unpublished).
Temporal specificity of collection data also varied greatly. The year of publication was
' used as the collection date in studies that provided no specific collection dates. To help
L'

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assess changes in distribution over time, collection locality data were split into historical
(up to and including collections made in 1979) and recent (collections made after 1979)
time categories. This division was chosen because substantial research efforts
throughout the UCRB were initiated around 1980.
For river reaches where historical
distribution information was lacking, fish
distributions in adjacent river reaches and
drainages, fish life-history characteristics,
and recent distribution patterns were used to
infer probable historical distribution patterns
(Figure 2). Thus, for historic distribution
maps, shading represents a combination of
range and transformed point data (~ 80%),
and inferred distributions (~20%). For
. = collation location
0 =infareddistribution
Figure 2. Example of an inferred
distribution pattern based on scant
locality data.
example, few recent fish collections were found
for most tributaries to the Gunnison River. However, based on historical collections of
study species in Tomichi Creek and the Cimarron River, tributary to the upper Gunnison
River, and presumed presence of similaz habitat in lower portions of other nearby
tributary streams, it seemed reasonable to extend species' historic ranges to lower reaches
of upper Gunnison River tributaries. Even with such assumptions, it is likely that our
historical distributions still under-estimate historical patterns, due to the overall lack of
' tributary sampling.

Final Report September 2002
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