Publicación: BREEDING BIOLOGY OF THE BLACK-FACED IBIS (THERISTICUS MELANOPIS) IN SOUTHERN CHILE
Fecha
2016
Autores
Título de la revista
ISSN de la revista
Título del volumen
Editor
WATERBIRDS
Resumen
THE BREEDING PARAMETERS OF THE BLACK-FACED IBIS (THERISTICUS MELANOPIS) IN PASTURES OF SOUTHERN CHILE BETWEEN 5 JULY AND 30 NOVEMBER 2014 WERE EVALUATED. THIRTY ACTIVE NESTS WERE MONITORED IN AN AREA OF 31 KM², USING A MIRROR MOUNTED ON A 13-M RETRACTABLE ALUMINUM POLE. EACH NEST WAS VISITED ONCE A WEEK. THE BLACK-FACED IBIS PRESENTED AN ASYNCHRONOUS POSTURE PERIOD, WITH A MAXIMUM OF THREE EGG CLUTCHES. THE FIRST EGGS WERE LAID ON 6 AUGUST 2014, AND THE MEAN INCUBATION PERIOD WAS 28.66 (± 4.41) DAYS. MEAN CLUTCH SIZE DURING THE FIRST POSTURE WAS 2.23 (± 0.73) WITH A RANGE OF ONE TO THREE EGGS PER NEST. NONE OF THE STRUCTURAL PARAMETERS OF THE NESTING SITE EVALUATED WERE RELATED TO CLUTCH SIZE. THE NESTS WERE ORIENTED WITH A MEAN ANGLE OF 218° SW. HATCHING OF THE CHICKS BEGAN ON 25 SEPTEMBER 2014, AND THE MEAN PERIOD OF PARENTAL CARE LASTED 36.67 (± 14.49) DAYS. THE APPARENT HATCHING SUCCESS WAS 0.54, THE FLEDGING SUCCESS WAS 0.40, AND THE TOTAL BREEDING CYCLE SUCCESS WAS 0.23 INDEPENDENT YOUNG PER NEST. PREDATION EXPLAINED THE 56.7% NEST LOSS. CHIMANGO CARACARA (MILVAGO CHIMANGO) WAS THE MAIN PREDATOR OF EGGS AND CHICKS. THE MAYFIELD ESTIMATOR INDICATED A DAILY SURVIVAL PROBABILITY OF 4.4% FOR THE INCUBATION CYCLE, 26.2% FOR THE FLEDGLINGS AND 11.3% FOR THE TOTAL BREEDING CYCLE.
