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Item type: Ítem , Access status: Acceso Abierto , Captura incidental de tortugas marinas durante El Niño 1997-1998, en el norte del Perú(Pontificia Universidad Católica de Valparaíso, 2012) Castro Gálvez, Javier; de la Cruz Galloso, Jaime; Ramírez Díaz, Paquita; Quiñones Dávila, JavierSe presenta evidencia del aumento de capturas incidentales de tortugas marinas en el norte del Perú, durante el fenómeno El Niño Oscilación del Sur (ENOS) 1997-1998. El área de estudio se ubica frente a Lambayeque, entre 6°20’S y 7°10’S, y desde la costa hasta 35 mn mar afuera. Se analizaron y describieron los aparejos de enmalle por ser los que más interactuaban con estas tortugas, así como las características de las embarcaciones. Se registraron las tortugas capturadas por la flota artesanal entre enero 1996 y diciembre 1998; se identificó las especies capturadas y se analizó la captura por unidad de esfuerzo (CPUE); la información se correlacionó con la temperatura superficial del mar (TSM). Se analizó un total de 265 operaciones de pesca, capturándose un total de 383 tortugas, correspondiendo 80,4% a la tortuga pico de loro (Lepidochelys olivacea), 19,3% a la tortuga verde (Chelonia mydas) y 0.2% a la tortuga carey (Eretmochelys imbricata). Se encontró una correlación altamente significativa entre las capturas de tortugas marinas y la TSM con un intervalo de confianza del 99% (Pearson; r = 0,787; σ = 0,000; N = 36). Se recomienda reforzar la colaboración entre entidades públicas y privadas para implementar medidas de manejo adecuadas para la conservación de estas especies amenazadas, sobre todo ante la eventualidad de un fenómeno ENOS.Item type: Ítem , Access status: Acceso Abierto , Foraging in Guanay cormorant and Peruvian booby, the major guano-producing seabirds in the Humboldt Current System(Inter-Reseach Science Publiser, 2012-07-03) Weimerskirch, Henri; Bertrand, Sophie; Silva, Jaime; Bost, Charly; Peraltilla Neyra, SalvadorThe Humboldt Current System is the most productive upwelling system globally in terms of fish and sustains huge populations of guano-producing birds as well as the world’s largest single-species fishery targeting the Peruvian anchovy Engraulis ringens. Peruvian boobies Sula variegata and Guanay cormorants Phalacrocorax bougainvillii are the most abundant seabird species in the system and feed mainly on anchovies. By using high precision GPS and time−depth recorders, we compared the horizontal and vertical movements of the 2 species to examine whether segregation occurs between their foraging areas and whether there is any evidence for prey depletion close to large colonies. A simultaneous acoustic cruise in the foraging area of the 2 bird species estimated the vertical and horizontal distributions of anchovy schools. During the study period in austral spring 2008, the 2 bird species foraged in the same area, at relatively short distance from the colony (average, 19 to 20 km). Both species foraged at similar times of the day, although Peruvian boobies tended to leave earlier in the morning and return later in the evening than did the cormorants. Foraging trips were similar in duration, distance covered and range. Peruvian anchovies were abundant and schools occurred at shallow depths (median, 7 m; range, 3 to 34 m), mainly to the north and west of the colony where foraging bouts of the 2 species overlapped extensively. Cormorants are mainly pelagic surface divers, diving at shallow depths (median, 4 m) but reaching up to 32 m depth, and are thus able to track all the depths at which anchovies occurred during the study period. Peruvian boobies are plunge divers able to reach occasionally 10 m (median, 2 m), and are thus able to reach only shallow anchovy schools. No sexspecific differences in horizontal or vertical movements occurred between males and females in the 2 species. We suggest that the absence of significant differences between horizontal movements of boobies and cormorants, the relative short duration of their trips and the high number of chicks fledged were probably explained by the high abundance and accessibility of anchovies. Differences may be exacerbated during years of low anchovy abundance or accessibility, especially El Niño years.Item type: Ítem , Access status: Acceso Abierto , Seasonal dynamics of sea surface salinity off Panama: The far Eastern Pacific Fresh Pool(Wiley, 2012-04-17) Alory, Gaël; Maes, Christophe; Delcroix, Thierry; Reul, Nicolas; Illig, SerenaThe freshest surface waters in the tropical Pacific are found at its eastern boundary. Using in situ observations, we depict the quasi-permanent presence of a far eastern Pacific fresh pool with sea surface salinity (SSS) lower than 33, which is confined between Panama's west coast and 85°W in December and extends westward to 95°W in April. Strong SSS fronts are found at the outer edge of this fresh pool. We investigate the seasonal dynamics of the fresh pool using complementary satellite wind, rain, sea level and in situ oceanic current data at the surface, along with hydrographic profiles. The fresh pool appears off Panama due to the strong summer rains associated with the northward migration of the ITCZ over Central America in June. During the second half of the year, the eastward-flowing North Equatorial Counter-Current keeps it trapped to the coast and strengthens the SSS front on its western edge. During winter, as the ITCZ moves southward, the northeasterly Panama gap wind creates a southwestward jet-like current in its path with a dipole of Ekman pumping/eddies on its flanks. As a result, upwelling in the Panama Bight brings to the surface cold and salty waters which erode the fresh pool on its eastern side while both the jet current and the enhanced South Equatorial Current stretch the fresh pool westward until it nearly disappears in May. New SMOS satellite SSS data proves able to capture the main seasonal features of the fresh pool and monitor its spatial extent.Item type: Ítem , Access status: Acceso Abierto , Boletín Diario Oceanográfico vol. 13 N° 279, 2026(Instituto del Mar del Perú, 2026-10-06) Instituto del Mar del Perú. Dirección General de Investigaciones Oceanográficas y Cambio ClimáticoPersisten las condiciones cálidas de hasta +8,0 °C en el litoral centro-norte. Asimismo, los núcleos con mayor intensidad se ubicaron frente a Paita (+9,16 °C) y Paracas (+8,51 °C).Item type: Ítem , Access status: Acceso Abierto , Boletín Diario Oceanográfico vol. 13 N° 278, 2026(Instituto del Mar del Perú, 2026-10-05) Instituto del Mar del Perú. Dirección General de Investigaciones Oceanográficas y Cambio ClimáticoSe registra un incremento en las anomalías frente a Paita con valores de hasta +9,37 °C, seguido por núcleos en Chimbote (+8,12 °C) y Pisco (+7,72 °C).
