Actividad reproductiva de la tuza Pappogeomys merriami merriami (Rodentia: Geomyidae) de Chalco, México

Abstract

REPRODUCTIVE CHARACTERISTICS OF A POPULATION OF PAPPOGEOMYS MERRIAMI MERRIAMI POCKET GOPHER WERE STUDIED IN THE NORTH OF THE VALLEY MEXICO (CHALCO, MEXICO) FROM 1981 TO 1982, USING CONVENTIONAL LIVE TRAPPING VICTOR TECHNIQUES. DATA ON 169 SPECIMENS WERE EXAMINED, 65 FEMALES, 60 MALES AND 44 YOUNG. MALE YOUNG POCKET GOPHERS DID NOT REPRODUCE UNTIL THEY WERE OVER 650G WILE FEMALES WERE 332G. THE DIFERENTES IN CONDITION OF SEX GLANDS , LENGHT OF TESTES, AND LENGHT OF EPIDIDYMIS CAN BE USED TO DISTINGHISH ADULT MALES FROM YOUNG MALES THAT HAVE NOT UNDERGONE A BREEDING CYCLE. ABOUT 35% OF THE FEMALES WERE PREGNANT AND 33% LACTATING ON THE STUDIED PERIOD. LITTER SIZE AVERAGED 2.0 PER FEMALE. CONCLUSIVE EVIDENCE SHOWED THAT ADULT FEMALES ARE REPRODUCTIVELY ACTIVE THROUGHOUT THE YEAR.