7016

• UCREFRP Catalog Number: 7016
• Author: Larval Fishes Laboratory.
• Title: Development of Marking and Otolith-ageing Techniques for Colorado Squawfish
• USFW Year: 1986.
• USFW - Doc Type: Report on Study-Phase 1.
• Copyright Material: NO

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DEVELOPM- E NT O .'•::? i? I DTs r is D -'T- L i T ::- A 1 7G
TECHNIQUES FOR COLORADO SQUAWFISH
REPORT ON STUDY-PHASE 1
Submitted 3 July 1986
to
Thomas P. Nesler
Wildlife Researcher C
Colorado Division of Wildlife (CDOW)
Fort Collins, Colorado 80526
by
Larval-Fish Laboratory (LFL)
Colorado State University
Fort Collins, Colorado 80523
0 701
In response to a request by Thomas Nesler; the LFL
prepared and submitted for consideration a proposal
involving a study to research and develop procedures for
marking and ageing larval Colorado squawfish (Ptychcheilus
lucius) (date of proposal submission was 2& April 1986).
The primary objective of the planned study is to develop
techniques for marking Colorado squawfish larvae (possibly
as embryos);development of ageing procedures is a secondary
objective. The study falls under the general purview of
CDOW project--"Endangered Fishes Investigations", Project
No. 02-01-035; specifically relating to Job Objective 2,
Approach 1, Segment 1--"Larval Drift Studies-to develop and
test a marking technique suitable for use on larval
Colorado squawfish". In general, the proposed study
consists of two options with three (Option 1) or four
(Option 2) sequential phases (the main difference between
Options 1 and 2 concerns timing of funding and start-up
date of the study--see proposal for details). A brief
description of each study-phase is as follows: Phase
1--survey and assess existing methods for marking and
ageing (using otoliths) fish eggs (embryos) and larvae and
determine the "best" methods with applicability to larval
Colorado squawfish; Phases 2 and 4 (depending on option
followed)--test and refine these methods under laboratory
conditions and develop definitive, reliable marking/ageing
procedures and criteria; Phases 3 and 4 (depending on
option followed)--final report(s).
To date, a formal contract between the CDOW and LFL
for the proposed work has not been signed; however, CDOW
consideration has been positive and agreement in principle
has been reached. For this reason and due to the
provisions of the study and specific timing required if the
work is to be completed during the 1986-1987 fiscal