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Falklands penguins - Falkland Islands penguins, seabirds, seals, sealions, birds and other Falklands wildlife.            
 International press reports of our work to save penguins - CLICK LOGO to view article
by Mike Bingham Electronic download: $3.95 Paperback: $10.95 Proceeds fund our Research
 by Mike Bingham available online or from bookshops world-wide. ISBN: 1420813757.
PLEASE HELP US TO SAVE PENGUINS
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.RESEARCH PUBLICATIONSFor people wishing to know more about our penguin research, you will find below a selection of recent publications. Maps and figures relating to these publications can be found in Picture Gallery 1. Any information used or copied from these reports MUST be referenced to the source article as given at the heading of each report.
6) Bingham M. and Mejias E. (1999) Penguins of the Magellan Region. Scientia Marina Vol:63, Supl. 1: 485-493
7) Bingham, M. (1999) Field Guide to Birds of the Falkland Islands.
------------------------------------------------------------------------------------- Magellanic Penguin Monitoring Results for Magdalena Island 2000-08by Mike Bingham and Thora Herrmann - Published 2008 in Anales Instituto Patagonia (Chile) 36(2): 19-32. ABSTRACT
Magellanic penguins (Spheniscus magellanicus) are only found around southern South America, with breeding populations in Chile, Argentina and the Falkland Islands. One of Chile's largest and most important Magellanic penguin breeding sites is situated on Magdalena Island in the Straits of Magellan. The island has been designated a national nature reserve because of its importance as a penguin breeding site, and the reserve is managed by the government agency Corporaci¢n Nacional Forestal. The island is a popular tourist destination, and Magellanic penguins are increasingly exposed to human activities. INTRODUCTION
Magellanic penguins (Spheniscus magellanicus) are only found around southern South America, with breeding populations in Chile, Argentina and the Falkland Islands. Best guess estimates put the current world population of Magellanic penguins at around 1.5 million breeding pairs, with approximately 700,000 pairs in Chile, 650,000 pairs in Argentina and 150,000 pairs in the Falkland Islands (Bingham 1998, Bingham & Mejias 1999, Gandini et al. 1998). MATERIALS AND METHODS Population Census
Because Magellanic penguins live below ground in burrows, and over such a large area, direct nest counts are not possible. Many burrows are unoccupied, and to assume that all burrows contain nests would greatly over-estimate the population size. It was therefore necessary to establish long-term study plots, in which to measure annual nest density. Breeding and Behavioural Analysis
In addition to studying population changes, in late October, shortly after egg-laying, around 20 occupied nests in each plot are marked, and these nests are visited regularly throughout the season, to determine what proportion of eggs hatch, how many chicks survive to leave the nest, the major causes of egg and chick loss, and chick weight. In addition to the seven study plots, occupied nests alongside the tourist path are also marked and studied, to look for differences in breeding success and chick survival rates resulting from the presence of large numbers of tourists. RESULTS AND DISCUSSION
A baseline survey of Magdalena Island was carried out in 2001, recording the terrain and associated flora and fauna, using methodology specified in specified in Hiscock (1993) and Bingham (2004). This allows any future changes in the vegetation, and fauna other than penguins, to be assessed at any time in the future, by carrying out a repeat survey. The results of this baseline survey are shown in
Fig 4 ,
Fig 5 ,
Fig 6 and
Fig 7. A similar survey of adjacent Contramaestre Island was conducted in 2002. TABLE 1: Breeding success over the last 8 years (2000 to 2007) Data
source: © Mike Bingham, Organization for the
Conservation of Penguins,
.
Comparison of nests alongside the tourist path, with nests in the study plots which are away from tourists (Table 1), shows a slightly higher breeding success for nests close to tourists (near to tourists = 1.17 chicks per nest / not near tourists = 1.10 chicks per nest). With only eight years of data, such a small difference may not be statistically significant, or it may be that predators of the penguins' eggs and chicks, principally skuas, tend to stay away from tourists, reducing the amount of predation on penguin nests near to the tourist path. What is apparent is that these penguins readily adapt to the presence of tourists, and are comfortable with the current level of tourism on Magdalena. Comparing the weight at fledging between the chicks raised within the tourist area and those raised in areas not visited by tourists, our data over a six year period (2002 to 2008) show tourist path chicks to be slightly heavier (average weight over six years = 3.34 kg) than non tourist areas chicks (average weight over six years = 3.31 kg), although the difference is so small that it is not statistically proven. In essence, penguins breeding in the tourist areas showed a significantly weaker behavioural response to approach then penguins nesting in undisturbed areas. The variation observed in the behavioural response of Magellanic penguins according to the amount of human disturbance is similar to observations made in other Magellanic penguin colonies in Patagonia (Yorio et al., 1998; Cevasco et al., 2001) and among other penguin species, e.g. Jackass penguins in South Africa (van Heezik & Seddon 1990). Annual monitoring of breeding success did reveal one area of concern for the future of penguins on Magdalena Island. During the 2002/03 season, breeding success was very low indeed, averaging just 0.42 chicks per nest, which would be insufficient to maintain the population if such conditions persisted. During the summer of 2001/02 virtually no rain fell on Magdalena Island, and as a result most of the grass on the island died. As a result by the 2002/03 season the island had lost most of its vegetation and was mostly covered in bare earth. The strong winds which always prevail in this area blew the loose earth across the island day after day, and by December 2002, most of the penguins' nests had been abandoned as a result of eggs and small chicks being buried in these dust storms. Fortunately 2002-03 was a fairly wet season, and by 2003-04 much of the vegetation had returned. However this incident does show just how fragile the penguins are to any climate change that reduced rainfall on Magdalena. Comparison of breeding success of nests in burrows and nests out in the open revealed surprising results. Most penguins on Magdalena Island nest in burrows, but a few penguins lay their eggs out in the open without the protection of any burrow. Most of these open nests become abandoned, suggesting that they are much less successful than nests in burrows, but that was not the case. Most open nests survive during the egg incubation period, and whilst the chicks are small and well protected by the parent, only to become abandoned when the chicks are left alone by both parents. However these nests mostly become abandoned not through the chicks being taken by predators, as had been assumed, but by the chicks leaving their open nest in search of a neighbouring unoccupied burrow. During 2001/02 breeding success for nests in burrows was 1.38 chicks per nest, and 1.06 chicks per nest for open nests, even though virtually all open nests had been abandoned (Table 1). This was largely the result of chicks seeking out the protection of nearby vacant burrows, rather than actual chick loss. Whether open nests are less experienced pairs, pairs that arrived late, or simply pairs that are cheating the system, is unclear. However only a small proportion of the colony can make use of this system, since they rely on occupying burrows built and subsequently abandoned by other penguins in order to avoid loosing their chicks. Annual counts of juveniles on the island conducted between 2000/01 and 2006/07 show that only a small proportion of Magdalena's juveniles return to the island prior to reaching maturity. Annual counts average around 3,000 juveniles per year, which is considerably fewer than would be required to maintain a stable population. Assuming a population of 60,000 breeding pairs, an active breeding duration of 15 years (aged 5 to 20 years), and a juvenile phase of only 3 years duration, a total of 24,000 juveniles would be expected on the island each year in order to provide a stable population. Since the population on Magdalena Island is actually increasing in size, the total number of juveniles surviving must be even greater, and yet the number actually counted on the island is very much less. Therefore it must be concluded that the great majority of surviving juveniles do not return to Magdalena until they reach maturity and begin breeding. CONCLUSIONS
Annual monitoring shows that penguin populations on Magdalena Island are healthy and increasing, and that Contramaestre Island is being colonised by penguins spilling over from Magdalena Island. Breeding success is high, egg and chick losses are low, and chicks are healthy and very well fed, suggesting high juvenile survival after leaving the nest. ACKNOWLEDGMENTS Our special thanks go to the Chilean National Forestry Corporation (CONAF) and the rangers of Magdalena Island (Domingo, Floridor, Louis, Neftali, Roberto, Luis) for their continuous help. We are very thankful to the crews of Melinka, Fueguino, Mare Australis, Tierra Australis, Via Australis, Don Jorge, Hundy, Mandamiento and Solo Expediciones for their logistical support. Mike Bingham would like to thank his research assistants Nidia Mendez, Elena Mejias, Cici Legoe, Christopher Burney, Jennifer Rock, Jon Philipsborne and Joseph Brandt . Financial support was kindly provided by the Darwin Initiative (British Government), ENAP, the Canada Research Chair in Ethnoecology and Biodiversity Conservation, and members of the OCP's penguin adoption programme. LITERATURE CITED Bertea, L. & Herrmann, Th.M. (in press) El Pingüino de Magallanes: Colonias del Estrecho de Magallanes - Magellanic penguins: Colonies in the Strait of Magellan - Der Magellanpinguin: Kolonien in der Magellanstrae - Le manchot de Magellan: Les colonies du d‚troit de Magellan. Editorial Patagonia Interactiva, Chile, 120 p. Bingham, M. 1998. Penguins of South America and the Falkland Islands. Penguin Conservation 11(1): 8-15. Bingham, M. & E. Mejias 1999. Penguins of the Magellan Region. Scientia Marina Vol:63, Supl. 1: 485-493 Bingham, M. 2002. The decline of Falkland Islands penguins in the presence of a commercial fishing industry. Revista Chilena de Historia Natural 75: 805-818 Bingham, M. 2004. Seabird Monitoring Instruction Manual for Magdalena Island. Organization for the Conservation of Penguins, 22pp. Cevasco, C., E. Frere & P. A. Gandini 2001. Intensidad de visitas como condicionante de la respuesta del pingüino de Magallanes (Spheniscus magellanicus) al disturbio humano. Ornitologia Neotropical 12:75-81 Gandini P., E. Frere & D. Boersma 1998. Status and conservation of Magellanic Penguins in Patagonia, Argentina. Bird Conservation International. Hiscock, K. 1993. A manual for marine biological inventory surveys. Joint Nature Conservation Committee Report MNCR/OR/19 van Heezik Y., & P.J. Seddon 1990. Effect on human disturbance on the breeding behaviour of Jackass Penguins. South African Journal of Wildlife Research 20: 89-93 Yorio P. & D. Boersma 1992. The effects of human disturbance on Magellanic Penguin Spheniscus magellanicus beahaviour and breeding success. Bird Conservation International 2:161-173
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