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PENGUIN RESEARCH PUBLICATIONS IN ENGLISH:
Bellew L (2019) The Chilean island where the presence of cruise passengers is helping penguins breed. The Telegraph, 1st August 2019
Bingham M and Mejias E (1999) Penguins of the Magellan Region. Scientia Marina Vol:63, Supl. 1: 485-493
Bingham M (1999) Field Guide to Birds of the Falkland Islands. .
PUBLICACIONES CIENTIFICOS EN ESPANOL:
Bingham M (2004) Manual de Instrucción para Monitoreo de Aves Marinas.
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Penguins of the Magellan RegionBingham M. and Mejias E. Published in Scientia Marina 1999 Vol: 63, Supl. 1: 485-493ABSTRACT The Magellanic Region, including the Falkland Islands, is one of the world's most important areas for seabirds, and especially penguins. World-wide there are 17 species of penguin; 7 of these regularly breed around the coastal waters of South America, and 5 within the Magellanic region. These are the King Penguin (Aptenodytes patagonicus), Gentoo Penguin (Pygoscelis papua), Rockhopper Penguin (Eudyptes chrysocome chrysocome), Macaroni Penguin (Eudyptes chrysolophus) and Magellanic Penguin (Spheniscus magellanicus). During the last 4 years, a review of the breeding populations of penguins within the Magellanic Region was conducted. This work included population censuses of all the surface breeding species throughout the Falkland Islands and southern South America. The results of this work are presented, along with other cited information, to provide a summary of the current knowledge of penguin populations within the Magellanic Region. RESUMEN Durante los 4 años adras, investigamos las poblaciónes de los pingüinos en el area de Magallanes. Esta investigacion incluyó cuentas de todas las especies que crian encima de la tierra por todas partes de Islas Falklands y Sud America del sur. Presentamos nuestros resultados con información de otra literatura, para hacer un resumen de las poblaciónes de los pingüinos en el area de Magallanes. INTRODUCTION Of the 5 species of penguin that regularly breed within the Magellanic Region, the Magellanic Penguin is the most numerous and widespread (Bingham 1998). It only breeds around the coasts of Chile and Argentina, and at the Falkland Islands. The King Penguin has a limited presence in the region, with a breeding population of around 400 pairs in the Falkland Islands (Bingham 1996). King Penguins have not bred in South America since the colony on Islas de los Estados was wiped out by sealers during the last century (Clark 1986). The Falkland Islands hold around 20% of the world population of Gentoo Penguin, with a total population of 65,000 breeding pairs at 81 sites (Bingham 1996). The Falkland Islands and South America are home to two species of the Genus Eudyptes; the Southern Rockhopper and the Macaroni (Bingham in 1998b). The Southern Rockhopper is a subspecies that is restricted to the Falkland Islands and South America, with the Falkland Islands holding a breeding population of about 300,000 pairs at 36 sites (Bingham 1996). The Falkland Islands population of Macaroni Penguins is very small, with no individual colonies and only individual pairs found breeding amongst Rockhoppers colonies. The total Falklands population stands at no more than about 50 pairs (Bingham in 1998b). THE CENSUS During 1995/96, a population census of all penguin species (except the Magellanic Penguin) was conducted around the Falkland Islands (Bingham 1996). Every breeding colony was visited, and population totals for each species obtained. Comparing this data with previous studies revealed that the Southern Rockhopper population had crashed to a fraction of its former size (Bennett 1933, Bingham 1994c Bingham 1995a, Bingham 1996). With no obvious reason for this dramatic decline, apart from speculation about commercial fishing, it became a priority to census the remainder of the world population located in South America, to determine how wide-spread the decline had been. It had been shown during the 1995/96 census of the Falkland Islands, that it requires little extra effort to census all penguin species during the course of such a census. The only exception to this was the Magellanic Penguin, which because of its widespread, low-density distribution in burrows, made it impossible to census with methods employed for surface nesting species (Bingham 1996). For this reason the Magellanic Penguin had been excluded from the Falkland Islands census. On that basis it was decided that a census would be conducted of all South American penguins during the 1996/97 breeding season, except for those of the Genus Spheniscus. During the 1995/96 Falkland Islands census it had been possible to conduct ground counts of incubating pairs at each of the breeding colonies, because most colonies were relatively accessible (Bingham 1996). By contrast, many of the South American colonies are remote and inaccessible, and any attempt to conduct ground counts of each and every colony would have been doomed to failure. It was therefore decided from the outset that the census would be conducted by light aircraft, thereby negating the need to get ashore at difficult and remote sites. The location of all the Falkland Islands breeding sites had been known prior to the commencement of the 1995/96 census (Bingham 1996), but this was certainly not the case for South America. Although data did exist for a number of known breeding sites around South America (Croxall in press, Frere et al. 1993, Venegas 1984, 1991, Woehler 1993), it was likely that other sites existed which had not been recorded. This was another reason for favouring an aerial census, since it provided the opportunity to cover large areas of suitable coastline in search of previously unrecorded colonies. This certainly reduced the margin of error that would otherwise have arisen from new sites being overlooked, however the margin of error for aerial counts was likely to be higher than for ground counts. In order to quantify the margin of error likely to be expected from aerial counts, a number of aerial censuses were made of Rockhopper colonies in the Falkland Islands for which the number of breeding pairs was also determined by ground counts. These aerial counts differed by a maximum of 14% from ground counts made of the same colony, giving a total margin of error of +/- 20% for aerial census data (Bingham 1996). The 1996/97 aerial census was conducted throughout the known Eudyptes breeding ranges of Chile and Tierra del Fuego (Woehler 1993). The Atlantic coast of mainland Argentina was excluded from the census, since this coastline has been well studied, and does not hold any breeding sites for species covered by the census, other than a very small Rockhopper colony on Isla Pingüino, near Puerto Deseado (Frere et al. 1993, Gandini et al. in press). This colony is regularly monitored as part of an ongoing research programme, and population data from their research was used in favour of duplicating results (Frere et al. 1993). CENSUS RESULTS King Penguin Gentoo Penguin Southern Rockhopper
Penguin Macaroni Penguin DISCUSSION The Falkland Islands population of around 400 breeding pairs of King Penguins has rapidly expanded from a population of less than 100 pairs recorded during 1980/81 (Bingham 1995a). With a world population of around 1,500,000 pairs (Croxall, In press), the Falkland Islands population is of regional rather than global importance. The Falkland Islands population of around 65,000 breeding pairs, recorded during the 1995/96 census (Bingham 1996), represents about 20% of the world population of 320,000 pairs (Croxall, In press). The 1995/96 Falkland Islands census indicated a population decline of around 45% since a similar census conducted during 1932/33 (Bennett 1933). Annual counts of selected breeding sites around the Falkland Islands suggested that much of this decline had occurred during the late 1980s and early 1990s, with low breeding success also being observed during that period (Bingham 1994a, Bingham 1994d, Bingham 1995a). Continued monitoring of these sites since then, indicates that the Falkland Islands population has now risen to around 81,000 breeding pairs, with high breeding success rates having been recorded since 1993/94. Gentoo populations are known to fluctuate greatly, and it is plausible that the decline observed previously was merely part of a natural cycle. The world population of Southern Rockhopper Penguins now stands at around 475,000 breeding pairs, with 63% of the population in the Falkland Islands and 37% in South America. Comparison with previous census data (Bennett 1933) indicates that the Falkland Islands population has crashed to just 10% of its former size, with much of this decline having occurred during the 1980s and early 1990s (Bingham 1994c, Bingham 1995a, Bingham 1996). Evidence of this dramatic decline can also be seen from the breeding sites themselves. The Falkland Islands breeding sites feature old colonies which have destroyed the vegetation by years of occupancy, leaving only lichen covered rocks and stones around the nest-site. The huge breeding colonies that once produced these areas of barren ground, have now been reduced to small clusters of birds huddled in the centre of their stony territories. The South American population shows no such evidence of decline, with breeding sites featuring a healthy mixture of new, middle-aged and old colonies, indicating a natural cycle of fluctuation and regeneration. Comparison with previous census data (Venegas 1984, Venegas 1991, Woehler 1993) also indicates that the South American population was stable throughout the 1980s and 1990s, during which the Falkland Islands population crashed (Bingham 1996). The reason for such differing fortunes is unknown, although it is interesting to note that the waters around Tierra del Fuego and Chile are not heavily fished, whilst those around the Falkland Islands are. In the Falkland Islands, even internationally recognised sites, such as Beauchêne Island which is being considered for World Heritage status, have fleets of fishing boats operating just 3 miles from breeding Rockhoppers. The Macaroni populations of South America (12,000 pairs) and the Falkland Islands (~50 pairs) must be looked at in the light of a world population of around 9 million breeding pairs (Croxall, In press). These populations are therefore of regional rather than international importance. There were no obvious signs of decline amongst the South American population, and no evidence to suggest that the population has changed greatly over recent years. The Macaroni is the most numerous of all the world's penguins. Although the Magellanic Penguins were not included in the 1995/96 and 1996/97 censuses, that is not to say that no work has been done on this species. The current population along the coast of mainland Argentina is estimated to be 650,000 breeding pairs (Gandini et al. In press). Observations of distribution around Tierra del Fuego and Chile during the 1996/97 census suggest that these regions hold a population at least as large as that of mainland Argentina, giving a South American population of at least 1,300,000 pairs. The Falkland Islands population is well in excess of 100,000 pairs (Bingham 1998), giving a minimum world population of around one and a half million breeding pairs. Annual monitoring of selected colonies (Bingham 1994b, Bingham 1995a, Bingham 1995b) shows that the Magellanic Penguin population of the Falkland Islands has declined to about half its 1980s level. These declines coincided with observations of low breeding success up until 1993/94. In addition to its Penguin Monitoring Programme in the Falkland Islands, the Environmental Research Unit now conducts similar studies at a number of Chilean breeding sites along the Straits of Magellan. These studies suggest that the Magellanic Penguin decline observed in the Falkland Islands has not been evident in the Magellanic region of Chile, despite its close proximity and similar breeding habitat to the Falkland Islands (Bingham 1998). Further evidence of the differing fortunes of the two regions can be seen from the breeding sites themselves. Magellanic Penguin colonies around the Falkland Islands generally feature a very high percentage of unoccupied burrows, with an average of more than 70% of burrows being unoccupied. Similar breeding sites in the Straits of Magellan hold less than half the proportion of unoccupied burrows (< 35%), suggesting lower levels of adult mortality or higher levels of recruitment (Bingham 1998). There is no commercial fishing activity around the Straits of Magellan. REFERENCES Bennett, A.G. (1933) The penguin population of the Falkland Islands in 1932/33. Government Press, Falkland Islands. 4pp. Bingham, M. - (1994a) Conservation Report on Gentoo Penguins. Penguin News, Vol.6, No.4: 9. Bingham, M. - (1994b) Conservation Report on Magellanic Penguins. Penguin News, Vol.6, No.20: 10. Bingham, M. - (1994c) Conservation Report on Rockhopper Penguins. Penguin News, Vol.6, No.21: 9. Bingham, M. - (1994d) Gentoo Penguin population trends: 1987/88 - 1993/94, The Warrah, 5: 4-5. Bingham, M. - (1995a) Population status of penguin species in the Falkland Islands. Penguin Conservation, 8(1): 14-19. Bingham, M. - (1995b). Seabird Surveys: 1994-95 Report. The Warrah, 5: 5. Bingham, M. - (1996) Penguin Population Census 1995-96. The Warrah, 10: 6-7. Bingham, M. - (1998) Penguins of South America and the Falkland Islands. Penguin Conservation, 11(1): 8-15. Bingham, M. - (1998b) The distribution, abundance and population trends of Gentoo, Rockhopper and King Penguins in the Falkland Islands. Oryx, 32(3): 223-32. Clark, R. - (1986) Aves de Tierra del Fuego y Cabo de Hornos. l.o.l.o. Croxall, J.P. (ed.) - In Press. Penguin Conservation Assessment: Antarctic and Subantarctic Species. In: Ellis, S. (ed.) Penguin Conservation Assessment. IUCN Conservation Breeding Specialist Group. Frere, E., Gandini, M., Gandini, P., Holik, T., Lichtschein V. and Day M.O. - (1993) Variación anual en el número de adultos reproductivos en una nueva colonia de pingüino penacho amarillo en Isla Pingüino (Santa Cruz, Argentina). Hornero, 13: 293-294. Gandini, P., E. Frere and P.D. Boersma - In Press. Status and conservation of Magellanic Penguins in Patagonia, Argentina. Bird Conservation International. Venegas, C. - (1984) Estado de las poblaciones de Pingüino de Penacho Amarillo y Macaroni en la Isla Noir, Chile. Informe Instituto de la Patagonia, 33. Venegas, C. - (1991) Estudio de cuantificacion poblacional de pingüinos crestados en Isla Recalada. Informe Instituto de la Patagonia, 55. Woehler, E.J. - (1993) The distribution and abundance of Antarctic and Subantarctic Penguins. SCAR, Cambridge.
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