7727

• UCREFRP Catalog Number: 7727
• Author: Stuber, R. J., G. Gebhart and O. E. Maughan.
• Title: Habitat Suitability Index Models
• USFW Year: 1982.
• USFW - Doc Type: Green Sunfish.
• Copyright Material: NO

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Table 1. (concluded).

Variable and Source

Assumption

V 15

Jenkins 1976

Total dissolved solids (TDS) levels
correlated with high standing crops of
sportfish are optimum; levels correlated
with lower standing crops are suboptimum.
The data used to develop this curve are
primarily from southeastern reservoirs.

Va

Moyle and Nichols 1973

The average percent of bottom covered
by rooted vegetation where green sun-
fish were collected (35%) is the optimal
percent. The optimal percent of
littoral area is that percent that can
result in 35% of the bottom of total
lake covered by vegetation,
when there is 80% cover in any given
area.

V17

Hunter 1963
Carson 1968

Stable water levels during spawning
ensure optimal survival of eggs.
Decreasing water levels are suboptimal
to unsuitable.

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V18

Kilby 1955 (BG)
Tebo and McCoy 1964 (BG)

Salinity levels where green sunfish
are most abundant are optimal. Levels
that reduce growth are suboptimal to
unsuitable.

Key: BG - bluegill data; other citations are green sunfish data.

Sample data sets from which HSI's have been generated using the riverine
HSI equations are in Table 2. Similar sets using the lacustrine HSI equations
are in Table 3. These data sets are not actual field measurements, but
represent combi nat ions of vari ab leva lues that coul d occur in a ri veri ne or
lacustrine habitat. The HSI's calculated from the data rank the sites in the
order that we believe represents the carrying capacity in riverine and
lacustrine habitats with the listed characteristics. The relationship of the
model-generated index to other indices of carrying capacity, such as produc-
tion or standing crop, is unknown.

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