7787

• UCREFRP Catalog Number: 7787
• Author: Desert Fishes Council.
• Title: Proceedings of the Desert Fishes Council Volume XXV, 1993 Annual Symposium.
• USFW Year: 1993.
• USFW - Doc Type: D. A. Hendrickson, ed. November, 10 -14.
• Copyright Material: NO

'PROCEEDINGS OF THE DESERT FISHES COUNCIL 1993 - VOLUME XXV
de actividad y use de habitat. Nuestro muestreo pasivo fue complementado con muestreo con redes de chinchorro,
y cuando ]as condiciones to permitieron, con observaciones. Los patrones de use de microhabitat determinados con
otros metodos de muestreo corroboraron los resultados de la metodologfa de muestreo pasivo. Nuestros metodos
de muestreo han sido usados en estudios en otros tributarios en el Gran Canon para evaluar su potencial pars apoyar
mas poblaciones reproductoras del charalito jorobado.
GORMAN, OWEN V; LEON, STUART C.; SEALS, JOHN M. OTG, 1MS - U.S. Fish atd Wildlife Service, P.O. Box 338, Flagstaff, AZ
86002-0338; SCL - U.S. Fish and Wildlife Servim, P.O. Box 39, Pinetop, AZ 85935
Habitat use by native fishes in the Little Colorado River in the vicinity of the Grand Canyon
Uso de habitat de peces nativos en el Pequeno Rfo Colorado en la vecindad del Gran Canon
KEYWORDS: Cyprinidae; Gila cypha; Catostomus latipinnis; Pantosteus discobolus; Rhinichthys osculus; ecology; streams; habitat; endangered
species; Grand Canyon
CLAVES: Cyprinidae; Gila cypha; Catostomus latipinnis; Pantosteus discobolus; Rhinichthys osctdus; ecologia; arroyos; habitat; species en
peligro; Gran Can6n
ABSTRACT
The objective of our study is to determine habitat use by the endangered humpback chub (Gila cypha) and other
native fishes in the Little Colorado River (LCR). During the day, adult chubs, flannelmouth suckers (Catostomus
latipinnis), and bluehead suckers (Pantosteus discobolus) used habitats with moderate to deep cover and substantial
vertical structure. At night, these fishes used a wider array of habitat types. In contrast, young-of-year (YOY) fishes
and speckled dace (Rhinichthys osculus) used open, shallow edge habitats and were most active during daylight
hours. Adult fishes showed a high degree of habitat segregation. Results of the LCR study will be used to evaluate
the potential for other candidate streams within the Grand Canyon to support additional reproducing populations of
humpback chub.
RESUMEN
El objetivo de nuestro estudio es determinar el use de habitat del charalito jorobado Gila cypha en peligro de
extinc16n, y otros peces nativos en el Pequeno Rfo Colorado (PRC). Durante el dfa, charalitos adultos, matalotes
boca de franela Catostomus latipinnis, y matalotes cabeza azul Pantosteus discobolus usan habitats con cobertura
moderada a prof inda y bastante estructura vertical. En la noebe estos peces usan un amplio rango de tipos de
habitat. En contraste los juveniles del ano y el pecesito moteado Rhinichthys osculus usan habitats abiertos como
orillas someras, y son mas activos durante ]as horas del dfa. Los peces adultos mostraron un alto grado de
segregaci6n de habitat. Los resultados del estudio en el PRC seran usados Para evaluar el potencial Para otros
arroyos candidatos para mantener poblaciones reproductoras del charalito jorobado en el Gran Canon.
MURAmA-ALVARADO, JAVWR Laboratorio de Acuacultt , Facuhad de Ciencias Biol6giws, Univenidad Autonomy de Nuevo Le6n
Comparison of four populations of Xiphophorus couchianus by means of biological parameters
Comparaci6n de cuatro poblaciones de Xiphophorus couchianus mediante la evaluaci6n
de parametros biol6gicos
KEYWORDS: Platy Monterrey; Monterrey Platy; artificial diets; dietas artificiales
ABSTRACT
The goal of this report is to help in the final decision about how to release captive specimens back to their
original site. In order to gain information we obtained fish from Dr. Klaus Kallman and Dr. Don Morizot who have
kept stocks for about 30 years under captivity. Stocks were also obtained from Apodaca and Cieneguita springs.
The main objective was to evaluate the effect of six diets upon fish "strains". These diets were live food, Tetra
conditioning flakes, catfish food, and three freshly blended mixtures: a) mostly vegetable; b) mostly animal proteins
and; c) a 50/50 mixture of vegetable and animal ingredients. The effects of these diets were assessed by keeping
the fish from newly born up to first reproduction and counting offspring. Every 15 days their length and weight gain
was recorded, the melanophores and sex ratio development was noted, and the effect of diet on survival was
determined. All these results are discussed.
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