6043

• UCREFRP Catalog Number: 6043
• Author: Desert Fishes Council ‎(Edwin Pister, e.
• Title: A Summary of the Proceeding of the Tenth Annual Symposium.
• USFW Year: 1978.
• USFW - Doc Type: November 16-18, 1978.
• Copyright Material: NO

44
RELACIONES DE ALIMENTACION DE PECES EN ARAVAIPA CREEK, ARIZONA.
Donald C. Schreiber, Arizona State University (now at University
of Oklahoma).
Se estudiaron habitos de alimentacion de siete especies nativas
de peces durante un tiempo de 13 meses en Aravaipa Creek, Graham
County, Arizona. Se estimo la disponibilidad de alimentos a los
peces por muestras del bentos y to llevado por la corriente. Se
presentaron tres nive,les troficos: herbivoria por Pantosteus clarki;
omnivoria por Agosia chryspgaster y carnivoria por las demas cinco
especies (Gila robusta, Meda'ful ida, Rhinichthys osculus, Tiaroga
cobitis, y Catostomus insignis . M, fas de Efemeroptera fueron la
comida predominante de los peces carnivoros y del omnivoro, y fueron
el invertebrato dominante en ambos el bentos y to llevado por la
corriente.
Cuando se disminuyeron dramaticamente las densidades absolutas,y
tamanos promedios de los cuerpos de ninfas de efimera, tres especies
de peces cambiaron a una rapina.diferente alterna, y tres otras no
respondieron obviamente. (Una especie, G. robusta, no se estudio
cuantitativamente). Los peces que respondieron a la rapina alterna
se aumentaron la especializacion de comportamiento de alimentacion y
repartimiento espacial del ambiente. Los que no repondieron se
quedaron Como generalistas en cuanto a su alimentacion. Interacciones
interespecifas relacionadas a habitos de alimentacion son'-probablemente
minimas en Aravaipa Creek por la abondanza de organismos comestibles
y segregation espacial de los peces.
FEEDING INTERRELATIONSHIPS OF FISHES OF ARAVAIPA CREEK, ARIZONA.
Donald C. Schreiber, Arizona State University (now at University
of Oklahoma).
Food habits of seven native species of fishes were examined over a
13-month period in Aravaipa Creek, Graham County, Arizona. Availability
of foods to the fishes was estimated by sampling benthic communities and
stream drift. Three trophic patterns were presented: herbivory by a
mountain-sucker (Pantosteus clarki); omnivory by longfin dace (Agosia
ch.rysogaster); and ca"rnivory by the remaining five species (Gila robusta,
Meda fulgida, Rhinichthys osculus, Tiaroga cobitis, and Catostomus insi -
nis Ephemeropteran nymphs were the predominant food of the carnivor-
ous fishes, and of the omnivore, and were the dominant invertebrate in
both benthos and drift.
When absolute densities and average individual body sizes of mayfly
nymphs decreased dramatically, three fish species each shifted to a
different alternate prey, and three others did not obviously respond.
(One species, G. robusta, was not studied quantitatively.) Fishes which
responded to alternate prey increased special feeding behavior and
spatial partitioning of habitat. Those which did not respond remained
as generalized feeders. Interspecific interactions related to feeding
habits are probably minimal in Aravaipa Creek because of the abundance
of food organisms and spatial segregation of the fishes.