Vol. 56, 2017
(update: 2017.12.15; 12.21)
Reproductive
Parameters of Female Long-finned Pilot Whales (Globicephala melas edwardii) from the Southwestern
Atlantic
Soto Florencia Anabella1,*, Grandi María
Florencia2, García Néstor Aníbal2,
Crespo Enrique Alberto2,3,
and Dans Silvana Laura2,3*
doi:10.6620/ZS.2017.56-39
1Universidad Nacional
del Comahue, Centro Regional Universitario Bariloche, Río Negro,
Argentina
2Laboratorio de Mamíferos Marinos, Centro para el
Estudio de Sistemas Marinos (CESIMAR). CENPAT-CONICET. E-mail:
grandi@cenpat-conicet.gob.ar; garcia@cenpat.edu.ar
3Universidad Nacional de la Patagonia San Juan Bosco,
Sede Puerto Madryn, Chubut, Argentina. Kike.Crespo@uv.es;
dans@cenpat-conicet.gob.ar
(Received 11 April 2017; Accepted 1 December 2017;
Communicated by Benny K.K. Chan)
Soto
Florencia Anabella, Grandi María Florencia, García Néstor Aníbal,
Crespo Enrique Alberto, and Dans Silvana Laura (2017) Mass
strandings represent a valuable source of information, especially when
it comes to difficult-to-access pelagic species, such as Globicephala
melas edwardii. We collected reproductive organs from 27 female pilot
whales stranded in Caleta Malaspina, Chubut, Argentina. Our main
objective was to analyze reproductive parameters of female long-finned
pilot whales in the southern hemisphere. To achieve this, we studied
age and reproductive status in order to approximate age and body length
at sexual maturity, breeding interval, and fertility of this
subspecies. The maturity state was determined by recording different
ovulation bodies obtained from histological sections and by assessing
the presence of milk in the mammary glands and a fetus, and we
concluded that 5 of the females were immature and 22 were mature
females. Finding mature females in different reproductive states
(resting, in lactation, pregnant, or pregnant and in lactation) along
with the great variety of fetus sizes would indicate that copulation
and birth are not governed by seasonality. Age at sexual maturity was 8
years old and length at sexual maturity would reach 365.50 cm. The
annual pregnancy rate was constant with age for mature females at 0.41
ovul / year, with a breeding interval of 2.4 years. The average
fertility varied between 0.19 and 0.21. All the parameters are within
the estimated range for females of the North Atlantic subpopulation,
except for the breeding interval, which was significantly lower than
estimates for the northern subspecies. This study could be limited
because all individuals come from a single mass stranding. While this
study allowed us to reach some conclusions about the reproductive
biology of female G. melas edwardii in the Southwestern Atlantic Ocean,
further studies are needed to fully comprehend the behavior and biology
of this species.
Key Words: Age at sexual maturity, Breeding
cycle, Fertility, Length at sexual maturity, Ovarian activity.
Correspondence: Fax: +54 0280 488-3184. E-mail:
sotoflorenciaa@gmail.com
Citation: Anabella SF, Florencia GM, Aníbal GN, Alberto
CE, Laura DS. 2017. Reproductive parameters of female long-finned pilot
whales (Globicephala melas edwardii) from the Southwestern Atlantic. Zool Stud 56:39. doi:10.6620/ZS.2017.56-39.
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