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Localización del islote Albatros donde se halló el nuevo sitio de reproducción de albatros ceja negra, D. melanophris .
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ANTECEDENTES Los lugares de reproducción del alba-tros de ceja negra, Diomedea melanophris Temmink 1828 (Aguayo-Lobo et al. 2001, infor-man sobre el nombre genérico usado por otros autores), conocidos hasta el momento en el país, corresponden a las islas Diego de Almagro, islas Ildefonso e isla Diego Ramírez (Pisano 1972, Clarke et al 1992, Schlatt...
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Context 1
... Los lugares de reproducción del albatros de ceja negra, Diomedea melanophris Temmink 1828 (Aguayo-Lobo et al. 2001, infor- man sobre el nombre genérico usado por otros autores), conocidos hasta el momento en el país, corresponden a las islas Diego de Almagro, islas Ildefonso e isla Diego Ramírez (Pisano 1972, Clarke et al 1992, Schlatter & Riveros 1997, Gales 1998, Aguayo-Lobo et al 2001) (Fig. 1). Para el hemisferio sur, las poblaciones nidificantes del albatros ceja negra fueron informadas por Gales (1998). Las principales se ubican en las islas del Atlántico sur occidental, como islas Malvinas con 548.924 parejas reproductivas, Georgia del Sur con 96.252 parejas; seguida por las que se ubican en el Pacífico sur oriental (Chile) como isla Diego de Almagro, islas Ildefonso y Diego Ramírez, con una población que suma 51.000 parejas. Los grupos reproductivos se agrupan después en las islas Crozet, Kerguelen, McDonald, Heard y Macquarie, en el océano Índico, sumando allí 5.013 parejas. Los grupos ...
Context 2
... más pequeños son los que se dis- tribuyen en el océano Pacífico occidental como islas Snares, Campbell y Antípodas que sólo su- man 131 parejas reproductivas. De lo anterior se desprende que de las 701.320 parejas reproductivas de todo el hemisferio sur, sin considerar a las islas Malvinas, en las islas chilenas se reproducen el 35,8% de las 142.396 parejas reproductivas restantes. En consecuen- cia, encontrar un nuevo sitio de anidamiento del albatros ceja negra en islas chilenas es importan- te comunicarlo a la comunidad científica. Área de estudio Bahía Azopardo se encuentra en el ex tremo oriental de Seno Almirantazgo. En su saco se localiza la caleta Benavente donde desemboca el río Azopardo que tiene su origen en el lago Fagnano (Anónimo 1991). El islote innominado al que denominaremos islote Albatros, se encuentra en bahía Azopardo, entre la isla Tres Mogotes y la caleta Benavente, hallándose un poco al norte del eje de la bahía mencionada (Fig. 1). El pequeño islote Albatros se ...
Citations
... The main breeding colonies of black-browed albatross can be found at the Falklands/Malvinas, southern Chile and South Georgia accounting for 72%, 18% and 8% of the total population, respectively (BirdLife International 2024). One of the smallest and recently described black-browed albatross breeding colonies is at Albatross Islet in Tierra del Fuego, Chile (Aguayo et al. 2003), which has a maximum of 65 breeding pairs (Robertson et al. 2017;Droguett et al. 2023). Arata et al. (2014) hypothesized that this new colony may have been started by birds from other Chilean colonies as black-browed albatrosses tracked from those colonies are known to use inner fjord and channel waters during breeding. ...
A small colony of black-browed albatrosses (Thalassarche melanophris, 21–65 breeding pairs) was discovered in 2003 on Albatross Islet, Tierra del Fuego, Chile. The formation of new breeding sites is important from an ecological and evolutionary perspective. This colony is particularly significant because it is the only one recorded for the species in a land-locked area. As its population dynamics could be shaped by stochastic and other factors affecting small populations, understanding the variables influencing its persistence, such as source of breeders, is crucial. Here, we used genetic markers (mitochondrial control region) to determine the origin of individuals at this new breeding site. Our results show that the new colony is an even mix of birds from Chilean colonies to the south and west (52%) and Falklands/Malvinas birds to the east (48%). Understanding the unique characteristics of this colony provides valuable insights for the conservation of black-browed albatrosses given increasing anthropogenic and environmental changes.
... Se caracteriza por la presencia de turberas de ciperáceas y matorrales con michay (Berberis ilicifolia), mientras que en el borde costero es posible encontrar un bosque siempreverde de canelo (Drymis winteri) y coigüe de Magallanes (Nothofagus betuloides), sobre la costa sur y sur oriente. En la costa norte del islote se encuentra ubicada una colonia albatros de ceja negra, compuesta por un promedio de 44 nidos activos cada año (Droguett et al. 2021), en una zona de acantilados con pendiente superior a los 45 grados (Aguayo et al. 2003). ...
... El Islote Albatros es el único sitio de reproducción del albatros de ceja negra en aguas interiores (Aguayo et al. 2003, Droguett et al. 2021, y, por lo tanto, un sitio prioritario para el control de especies invasoras que podrían afectarlo, como el visón, que también podría afectar a la conservación del huillín. En ese sentido, los esfuerzos sistemáticos de monitoreo contribuirían a aportar con datos para la toma de decisiones informada sobre el manejo del AMCP-MU SA. ...
Entre las especies de mamíferos con hábitos semiacuáticos presentes en Chile se encuentran dos mustélidos nativos, el chungungo (Lontra felina) y el huillín (Lontra provocax). Asimismo, han sido introducidos dos mamíferos semiacuáticos exóticos e invasores en el país, el visón americano (Neovison vison) y el castor americano (Castor canadensis). Estas últimas especies son ampliamente reconocidas por los efectos negativos que provocan sobre los ecosistemas y las especies nativas. Si bien todas estas especies incluyen en su distribución más austral al archipiélago de Tierra del Fuego, en la región de Magallanes, existen pocos antecedentes documentados sistemáticamente sobre su presencia en canales interiores. En este estudio se describe la presencia de mamíferos semiacuáticos mediante el monitoreo con cámaras trampa en el Islote Albatros, en el Seno Almirantazgo entre las temporadas estivales 2016 – 2017 y 2021 – 2022, con esfuerzos de muestreo (EM) que variaron entre 499 durante la temporada 2018-2019 y 3.658 en 2020-2021. A partir de los registros obtenidos se calcularon los índices de abundancia relativa (IAR) para cada una de las especies registradas: visón americano (rango=0-8), huillín (rango=0,08 – 5) y castor americano (rango=0-0,144). Se destaca el primer registro de presencia de castor y huillín para el Islote Albatros, confirmándose además la reproducción de esta última especie en este. Estos hallazgos resultan de gran relevancia en el contexto de los objetos de conservación del Área Marina Costera Protegida de Múltiples Usos (AMCP-MU) Seno Almirantazgo, pues son un aporte clave para la toma de decisiones informada y el manejo efectivo de esta área protegida. También resaltan la importancia de implementar y sostener esfuerzos de monitoreo sistemáticos tanto de los objetos de conservación del área como de las amenazas que enfrentan.
... In particular, the presence and activity of predatory bird species in this colony have not been studied. The only information available are field observations on the presence of an Andean condor and Catharacta chilensis overflying the BBA colony (Aguayo et al. 2003). Here document the identity and activity of native avian predators and their interaction with the breeding activity and success of the BBA colony of Islote Albatros and discuss its incidence in the management of MPAs when predators are also threatened native bird species. ...
The breeding season is the most vulnerable period in the early stages of the life cycle of seabirds, due to the exposure of their eggs and chicks to the impact by predators. Most of the studies on predator–prey relationships between the Black-browed albatross (Thalassarche melanophrys) and other predators like raptors, were carried out in breeding colonies located in oceanic and highly isolated areas, such as Antarctic islands. However, breeding colonies located in the Sub-Antarctic fjords have not been studied. The geographical position of the study colony makes it susceptible to a wider spectrum of predators than the oceanic islands. Therefore, it is unknown how predation dynamics affect the reproductive success of this species. Here, we show for the first time the identity and activity of avian native predators on the colony in the inner waters of southern Tierra del Fuego, Chile. This study covered seventeen field visits between 2017 and 2020 to monitor the reproductive activity of this colony. In this study, we identified the interaction between predators, the breeding activity and success of albatrosses using direct census and camera traps. Across the study, the number of breeding pairs ranged from 64 (2017) to three (2019) breeding pairs of the Black-browed albatross. Terrestrial birds with occurrence on the colony were the Andean condor, Southern caracara, Chimango caracara and the Turkey vulture. Our results showed that the main avian predator species affecting the breeding success of the Black-browed albatross, were both the Andean condor and the Southern caracara. The Black-browed albatross is a conservation target in this area since of the colony of Islote Albatros is currently part of the Seno Almirantazgo Marine protected area. Therefore, baseline informations on species interactions are fundamental for its management particularly when native predators like the Andean condor are also threatened species globally.
... Recent population estimates have showed that about 96 % of their world population is confined to the waters around the southern tip of South America (Wakefield et al. 2011). In light of this fact, the discovery of new colonies in southern Chile in recent years should not be surprising Aguayo et al. 2003;Marin and Oehler 2007), increasing from three to six the number of breeding colonies of black-browed albatrosses for Chile and placing the country second worldwide with 20 % of their global population (Robertson et al. 2007). Considering that their main colonies are in remote oceanic islands located in productive areas with a high prevalence of strong winds (BirdLife International 2004;Wakefield et al. 2011), the existence of a small colony at the dead end of a channel in Tierra del Fuego, more than 275 km from open ocean, is remarkable (Aguayo et al. 2003). ...
... In light of this fact, the discovery of new colonies in southern Chile in recent years should not be surprising Aguayo et al. 2003;Marin and Oehler 2007), increasing from three to six the number of breeding colonies of black-browed albatrosses for Chile and placing the country second worldwide with 20 % of their global population (Robertson et al. 2007). Considering that their main colonies are in remote oceanic islands located in productive areas with a high prevalence of strong winds (BirdLife International 2004;Wakefield et al. 2011), the existence of a small colony at the dead end of a channel in Tierra del Fuego, more than 275 km from open ocean, is remarkable (Aguayo et al. 2003). ...
Black-browed albatrosses are the most abundant albatross species of the southern hemisphere, breeding on sub-Antarctic and Antarctic oceanic islands around the globe. Their foraging habitat during the breeding season is reasonably well known along its distributional range, indicating a preferred use of waters < 500 m deep. The discovery of a colony inserted within the Admiralty Sound, Tierra del Fuego, poses an interesting challenge to the known precepts on foraging behavior for the species. In this study, we present the first record on the foraging distribution of the only known inner-channel colony of albatrosses in the world, using high-resolution GPS loggers. Black-browed albatrosses breeding at the Albatross Islet used exclusively inner-channel waters, at least during the chick-guard stage. Our results indicate a significant smaller foraging range during chick-guard compared with conspecifics from Diego Ramirez and Falklands/Malvinas Islands. Implications for the conservation of this colony are discussed.
... The colonies at Islote Evangelistas were surveyed for the first time in October 2002 . The tiny colony at Islote Albatros, which lies deep inside the Chilean channels (in Seno Almirantazgo), was discovered and surveyed in January 2003 during chick rearing (Aguayo et al., 2003). Finally, the small colony at Islote Leonard was discovered and surveyed in November 2005 (Marin and Oehler, 2007). ...
... The censuses at Ildefonso and Diego Ramirez in 2002and 2011, and at Evangelistas in 2002, were made using photography from a twin otter aircraft (Robertson et al., 2007;. The population at Islote Albatros was surveyed in 2003 using yatch-based photography (Aguayo et al., 2003), and by aerial photography in 2006 and 2011 (Moreno and Robertson, 2008;this report). The population at Islote Leonard was assessed by ground count in 2005 (Marin and Oehler, 2007). ...
... Los derroteros de los navegantes en los siglos XVI al XIX (e.g., Cunningham, 1871) son los primeros que registran algunas colonias de aves marinas en el Estrecho de Magallanes. Posteriormente, por un lapso de más de cincuenta años, existen observaciones esporádicas y en las últimas décadas se han descrito más sitios de nidificación, en particular para especies de pingüinos (Bingham & Mejias, 1999;Oehler et al., 2008), albatros y petreles (Aguayo et al., 2003;Lawton et al., 2006;, pero sin embargo no existe un registro acabado de las especies que nidifican en la región o una actualización de la situación poblacional. ...
... Por lo tanto, la relación trófica de estos albatros con el interior del archipiélago subantártico puede constituir un importante rol en la dinámica poblacional de esta especie, siendo reconocido el uso de fiordos y canales por estas aves (Suazo 2008). Esta relación se reafirma por al menos tres razones: i) el descubrimiento relativamente reciente de numerosas colonias reproductivas del albatros de ceja negra al interior y alrededor del sistema de fiordos y canales subantárticos (e.g., Aguayo et al. 2003); ii) la presencia de Munida spp., uno de los decápodos más importantes en términos de abundancia en el sistema de canales y fiordos (Arntz et al. 1999), siendo un ítem presa importante en la dieta de los albatros de ceja negra que nidifican en las islas Diego Ramírez (Arata & Xavier 2003); iii) la oferta de descarte de la pesca artesanal de merluza austral, principalmente constituido por la merluza de cola Macruronus magellanicus (Lönnberg, 1907) y las estructuras blandas como las vísceras de merluza austral (e.g., hígados, gónadas y estómagos), siendo los hígados el ítem preferencial en el consumo de carroña de estas aves (Ojeda & Suazo 2008 5 ). ...
The fjords and channels of southern Chile represent breeding and feeding areas for sub-Antarctic seabird species. In addition, in these environments, an important artisanal austral hake Merluccius australis longline fishery operates. Studies on the relationship between seabirds and this activity are fundamental for the ecology and conservation biology of these birds. This study examined the composition and structure of the seasonal seabird assemblages attending the artisanal longline fishing activities in channels of the Southeast Pacific, Chile. Fieldwork was carried-out during summer (Cook Bay), winter (Felix Lighthouse), and spring (Gulf Xaultegua) of 2008. Ten species were associated with fishing activities. The most common seabird species observed during the year were the Black-browed albatross Thalassarche melanophrys and the Southern giant-petrel Macronectes giganteus. The seasonal structure of the assemblages presented differences between summer and winter. In terms of abundance, Black-browed albatrosses presented the highest contribution to the assemblage in summer (87.5%). During winter the Kelp gull Larus dominicanus showed the highest contribution (47.7%) while the Black-browed albatross abundance decreased to 9.1%. Black-browed albatross was the species with the highest index of relative importance within the assemblies, but is also a species with the conservation status 'endangered'. Therefore, it is necessary to maintain constant monitoring of the interaction between seabirds and artisanal longline fishing activities of sub-Antarctic environments.
... In addition to Ildefonso, black-browed albatrosses in Chile breed at Diego de Almagro (15,594 pairs in 2001/2002Lawton et al. 2003), the Evangelistas islets (4,670 pairs in 2002Arata et al. 2003), Diego Ramirez (55,300 pairs in 2002Robertson et al. 2003) and the newly discovered colony (18 January 2003) of <50 pairs in the Straits of Magellan (57°27Ј20 S; 69°01Ј12 W; Aguayo-Lobo et al. 2003). The total breeding population in Chile is about 123,000 pairs, of which Ildefonso contains 47,000 pairs or 38%. ...
A breeding population of black-browed albatrosses has been known to exist at the Ildefonso Archipelago,
Chile, for >90 years but the population has never been censused using scientiWcally defendable methods. To estimate population size, and examine the accuracy and practicality of various census methods, the population was censused in the 2002/2003 breeding season using (a) ground-truthed aerial photography, (b) yacht-based photography, (c) ground counts, (d) quadrat sampling and (e) point-distance sampling. Compared to ground-truthed aerial photography (judged the most accurate) yacht-based photography underestimated population size by 55%, ground counts by 13%, quadrat sampling by 11% and point-distance sampling by 9%. Ground-truthed air photography revealed that in the 2002/2003 breeding season 47,000 pairs of black-browed albatrosses bred at the Ildefonso Archipelago. A repeat aerial census in 2006 suggested the size of the breeding population had not changed in the 4 years between the two censuses. After the Falkland
Islands/Islas Malvinas, South Georgia and Diego Ramirez, the Ildefonso Archipelago holds the fourth largest population of black-browed albatrosses in the world.
... Nevertheless, it is noteworthy that other recent studies of colonial species in terrestrial and marine environments have also demonstrated the limiting effect on population size of habitat and food availability during the breeding season(Griffin & Thomas 2000, Laidre et al. 2008.At the level of individual colonies only 33% and 19% of the variance in N was explained by H * and P * respectively. Hence, other factors must account for the majorityAguayo et al. 2003, Martin & Oehler 2006), indicating that land area per se may be limiting. Indeed, as nesting black-browed albatrosses require steep slopes or cliffs from which to take off, the area of suitable breeding habitat may be limited even on large islands. ...
Chilean Patagonia encompasses the two southernmost terrestrial ecoregions of the temperate forest biome of South America (North-Patagonian and Sub-Antarctic Magellanic) and the two western marine ecoregions of the Magallanes Province (Chiloense, and Channels and Fjords of Southern Chile). These ecoregions are immersed in a complex mosaic of terrestrial (with marked altitudinal gradients), freshwater (including wetlands, rivers, lakes, and lagoons) and marine ecosystems (with myriad islands, channels, and fjords). With more than 100,000 km of coastline, most environments in the region exhibit strong land-sea interdependency in energy and nutrient flows. The goals of the chapter are to: (i) describe the main ecological features of the marine-terrestrial interface in the channels, fjords, and archipelagoes; (ii) identify major anthropogenic impacts on marine-terrestrial connectivity; (iii) describe the most important matter and energy flows across aquatic and terrestrial ecosystem; (iv) discuss the conservation status of species that are dependent on this interface; (v) identify those public protected areas that have extensive areas of marine-terrestrial interface. The major nutrient exchanges in the marine-terrestrial interface include carbon and nitrogen-rich sediment flows transported to the ocean by the rivers and streams, and abundant debris of siliceous rocks from land to ocean carried by rivers draining glaciers and ice fields. The most important vectors of biological transport of materials between the ocean and land are large marine mammals and seabirds. This includes historical records of whale landings that mobilize nutrients from ocean bottoms to the coastal zones and large populations of seabirds that nest in the archipelagos. Major threats to the marine-terrestrial interface include the massive populations of naturalized salmon that circulate in the fjords, streams, and channels. Salmon proliferation has altered the nutrient transport from the ocean to the continental rivers. Three species of exotic mammals have increased in numbers and impact at the interface between oceans, land, and freshwater systems—the beaver (Castor canadensis), the North American mink (Neovison vison), and the muskrat (Ondatra zibethicus). In contrast to traditional views on conservation and management that segregated land–ocean interfaces, our analysis in this chapter suggests that in order to understand ecosystem functioning in Chilean Patagonia as well as to establish comprehensive conservation programs, it will be essential to address the interrelationships of biophysical processes at the marine-terrestrial interface.