8045

• UCREFRP Catalog Number: 8045
• Author: Pacey, C. A. and P. C. Marsh.
• Title: Resource Use by Native and Non-Native Fishes of the Lower Colorado River
• USFW Year: 1998.
• USFW - Doc Type: Literature Review, Summary, and Assessment of Relative Roles of Biotic and Abiotic Factors in Management of an Imperiled Indigenous Ichthyofauna-Final Report.
• Copyright Material: NO

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All citations identified by our searches (summarized in APPENDIX II) were examined
for potential relevance to the Problem Statement. Those which clearly did not apply,
for example, biochemical, genetic, physiological, systematic, or taxonomic studies,
were not further considered. A second level of distillation involved identifying those
remaining materials for relevance to our specific problem statement, and acquiring
copies from a variety of sources (ASU libraries, interlibrary loans, colleagues, or
investigator's private collections). Materials were assembled categorically (see below)
and the type of study designated (i.e., field vs. laboratory, and by habitat, see Table 2
in REFERENCES USED), abstracts examined critically, and those works considered
germane scrutinized for qual- and quantitative information that could be usefully
analyses or otherwise interpreted to shed light on our basic questions.
PRESENTATION OF DATA -- Qual- and quantitative data derived from literature were
categorically assembled into a series of 2 x 2 matrices that allowed ready recognition of
potential overlap in resource use. Resources included physical and chemical features
of aquatic habitat, and life history features of target species. Resource use was
presented and examined separately for major life stages (i.e., larva, juvenile, and
adult). Larvae are defined as young fish from time of hatch to development of a full
complement of rayed-fins, and generally included stages referred to in non-specific, lay
terms as "fry." Juveniles were non-reproductive, post-larval stages, including those
generally termed "fingerlings." Adults were defined as sexually mature individuals,
including both reproductive and post-reproductive stages. Fish referred to as "young of
year" generally were assigned to the juvenile category. We did not find that term used
for species whose life history would result in "young of year" including two (or all) of the
larval, juvenile, and/or.adult stages (for example, many short-lived fishes like the
shiners [genus Cyprinella] and poeciliids [genera Gambusia and Poecilia], among
others) that mature sexually in less than a year.