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Vicugna vicugna Molina is a mammal of relatively large size and conspicuous habits; nevertheless, its southernmost distribution limit in Chile is not well established. Many authors were fixed this limit at 27º30´S, we deliver field information of a distribution limit 140 km further south to the recently proposed. Vicugna vicugna Molina es un mamífero de tamaño relativamente grande y de hábitos conspicuos; sin embargo, su límite de distribución Sur en Chile no está bien establecido. Muchos autores han fijado este límite a los 27º 30’S, nosotros entregamos información de campo de un límite de distribución 140 km más al sur al propuesto recientemente.

Se analizó la dieta del pequén (Athene cunicularia) en cuatro islas del norte de Chile, mostrando que existe un fuerte predominio de artrópodos (89,1%) en comparación con los vertebrados (10,1%) respecto al número de presas consumidas. De estos taxa destacan los tenebriónidos (42,2%) y curculiónidos (31,2%) como los principales grupos consumidos, sin embargo, la presencia de mamíferos (3,6%) y de aves (6%) en la dieta es también relevante, ya que a pesar de representar menos del 10% del número total de presas, el aporte energético de estos vertebrados constituyó cerca del 80% de la biomasa total ingerida. Se registró evidencias de depredación sobre el yunco (Pelecanoides garnotii); presa destacada con un 71% dentro del ítem aves y 40% del total de vertebrados consumidos, así también destaca el consumo de la llaca (Thylamys elegans) con en un 21% del total de vertebrados. Se encontraron tres individuos de piuchén o vampiro (Desmodus rotundus) especie no descrita con anterioridad en la dieta del pequén en el norte de Chile. Se discute respecto a las posibles respuestas funcional y numérica del pequén en isla Choros, asociadas a los registros de distintas densidades de yunco. Se analizó además, la variabilidad de la dieta por isla, el patrón de tamaño de las presas consumidas y la distribución espacial de nidos del pequén.

Humpback whales undertake seasonal migration between productive high-latitude areas where they feed in summer and low-latitude tropical waters where mating and calving occur during winter. In the eastern south Pacific, the species breeds off Colombia and Ecuador, and feeds primarily in the western Antarctic Peninsula and in the waters of the Strait of Magellan (SM), recently described as a new feeding ground for humpback whales. Comparison of fluke photographs of 62 individuals from the SM obtained during the austral summer from 1999 to 2005 and 1,042 individuals from Colombia, provided conclusive matches for six individuals, with an overall interchange Índex of 0.093. Eight migratory trips between summer and winter grounds were registered for four whales during a complete migratory round-trip in consecutive years. The mínimum distance traveled in a one-way trip ranged from 6,650 to 7,000 km. The duration of the two fastest trips between these migratory destinations was 88 and 99 days, with a mean speed of migration of 76 and 67 km day-1 respectively. Five of the whales present in both areas were males and three mitochondrial DNA haplotypes were identified: EM-1 for three individuals, EM-2 for two and EM-3 for the last one, all of which have been previously described for humpback whales from Colombia. All six individuals were seen several days in each season in the SM (as many as 39 days in one case), with an average stay of 72 ± 40 days (n = 20) per year, ranging from 3 to 125 days. On average, each of the six individuals was seen in the SM during 71 ± 18 % of the seven monitored summers. Three individuals were re-sighted in the SM six out of the seven surveyed years, during four to six consecutive years. These results provide the first direct evidence to include humpback whales that feed in the Strait of Magellan as part of the eastern south Pacific population of whales that feed off Colombian waters.

Humpback whales undertake seasonal migration between productive high-latitude areas where they feed in summer and low-latitude tropical waters where mating and calving occur during winter. In the eastern south Pacific, the species breeds off Colombia and Ecuador, and feeds primarily in the western Antarctic Peninsula and in the waters of the Strait of Magellan (SM), recently described as a new feeding ground for humpback whales. Comparison of fluke photographs of 62 individuals from the SM obtained during the austral summer from 1999 to 2005 and 1,042 individuals from Colombia, provided conclusive matches for six individuals, with an overall interchange Índex of 0.093. Eight migratory trips between summer and winter grounds were registered for four whales during a complete migratory round-trip in consecutive years. The mínimum distance traveled in a one-way trip ranged from 6,650 to 7,000 km. The duration of the two fastest trips between these migratory destinations was 88 and 99 days, with a mean speed of migration of 76 and 67 km day-1 respectively. Five of the whales present in both areas were males and three mitochondrial DNA haplotypes were identified: EM-1 for three individuals, EM-2 for two and EM-3 for the last one, all of which have been previously described for humpback whales from Colombia. All six individuals were seen several days in each season in the SM (as many as 39 days in one case), with an average stay of 72 ± 40 days (n = 20) per year, ranging from 3 to 125 days. On average, each of the six individuals was seen in the SM during 71 ± 18 % of the seven monitored summers. Three individuals were re-sighted in the SM six out of the seven surveyed years, during four to six consecutive years. These results provide the first direct evidence to include humpback whales that feed in the Strait of Magellan as part of the eastern south Pacific population of whales that feed off Colombian waters. La ballena jorobada migra estacionalmente entre latitudes altas donde se alimenta en verano y latitudes bajas donde cría y se aparea en invierno. En el Pacífico sureste, la especie se reproduce en Colombia y Ecuador y se alimenta principalmente al oeste de la península Antartica, y en el estrecho de Magallanes (EM) recientemente descrito como nueva área de alimentación. Al comparar las fotografías de las colas de 62 ballenas individualizadas en el EM durante el verano austral entre 1999 y 2005 con 1.042 individuos de Colombia, se encontró a seis individuos comunes, lo que representa un índice de Intercambio migratorio de 0,093. Se registraron ocho migraciones para cuatro de estas ballenas entre el EM y Colombia en el ciclo migratorio de años consecutivos. La distancia mínima recorrida en una sola dirección varió entre 6.650 y 7.000 km. La duración de los dos viajes más rápidos registrados entre estos dos destinos fue de 88 y 99 días, con una velocidad promedio de migración de 76 y 67 km día-1 respectivamente. Cinco de las seis ballenas comunes entre las areas fueron machos. Entre las seis ballenas se encontraron tres haplotipos de ADN mitocondrial todos descritos previamente en ballenas jorobadas de Colombia: tres ballenas con el haplotipo EM-1, dos con el EM-2 y uno con el EM-3. Los seis individuos se avistaron reiteradamente en el EM (hasta 39 días en una estación en un caso), con una permanencia promedio de 72 ± 40 días (n = 20) por año y un rango entre 3 y 125 días. En promedio, estas seis ballenas se vieron durante el 71 ± 18 % de las siete temporadas muestreadas en el EM y tres se registraron seis de lo siete años estudiados, por 4-6 años consecutivos. Esta es la primera evidencia directa para incluir las ballenas jorobadas que se alimentan en el estrecho de Magallanes como parte de la población del Pacífico sureste que se reproduce en aguas colombianas.