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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Task 5: Development of criteria for Applying
Increments of Managed Water for Recovery Purposes

The development of criteria for applying increments of managed
water for recovery purposes has been identified as one of the
tasks that is needed to achieve the goal of Phase I of the
Management Alternatives Work Group. In order to recover
threatened and endangered species on the Platte River system,
their life essential requirements must be met. These species
require habitat on and adjacent to the Platte River for a variety
of reasons. Platte River habitat is made of two major
components: land and water. This part of Task 5 addresses water
management. There is a need to prioritize the species' need for
water so that any water which is available for threatened and
endangered species can achieve the greatest benefit. The
following alternatives represent two potential ways of managing
Platte River water for the recovery of listed (threatened and
endangered) species.

Alternative 1: Species Ranking

Following is a list of possible criteria that could be used as a
guide to develop a species ranking strategy. The ranking would
be conducted each year to allocate available water. In case of a
tie score between two species, criterion (6) would be the tie-
breaker. The term "species" as used in the context of this plan,
only refers to listed species.

(1) If a species is endangered, it receives a higher rating than
a threatened species. The rationale is that endangered species
are at greater risk for possible extinction than threatened
species due to loss of habitat and other factors.

(2) If more than one species is endangered, the species with the
lowest population numbers would receive a higher rating; likewise
for threatened species. The rationale is that a species with a
lower population has a greater chance for becoming extinct than
another species with a higher population and therefore the first
species needs habitat more than the second species.

(3) A species reproducing on or adjacent to the Platte River
would receive a higher rating than another species which does not
reproduce on the river system. The rationale is that successful
reproduction is the cornerstone to species survival and that if
water in the Platte River system is essential to a species
reproduction, then that species needs habitat made available to
it more than other species.

(4) If a species uses the river more than once a year, then its
more critical period (e.g., spring) would receive a higher rating
than a less critical period (e.g., fall). For example, a species
uses the Platte River system during its spring migration to its
breeding/nesting grounds and uses the river system during its