I’ve closely followed the story of the Madagascar Pochard since its rediscovery in 2006. This duck must get the prize for the most elusive species; evading scientists, considered extinct, but in fact clinging on to survival for decades and then saved on the brink of extinction.
The Madagascar Pochard Aythya innotata was common at Madagascar’s largest lake; Lake Alaotra, during the 1930s but by 1960 the population had been reduced to such low numbers it was never seen again until an individual was sighted on Lake Ambohibao near Antananarivo in 1970. Ornithological expeditions to Lake Alaotra, many with the purpose of rediscovering Aythya innotata, were undertaken between 1971 and 1990. In 1989 and 1990 Glyn Young from Durrell Wildlife Conservation Trust (DWCT), J. G. Smith and L. Wilme in collaboration with World Wide Fund for Nature (WWF) and Wildfowl and Wetlands Trust (WWT) searched for the duck. Seven weeks of surveys concentrating on the extensive reed beds at the southern end of the lake revealed no signs of the species’ existence. Discussions with older generations of local villagers revealed good biological information on the species but no one had seen the duck for many years.
Astonishingly, 21 years since the last sighting, in August 1991, some local fowlers caught a single male on Lake Alaotra. The duck was transferred to the Zoological and Botanical Gardens in Antananarivo on 30th September 1991, but sadly died a year later. After the death of this captive individual, many people presumed Aythya innotata had gone the way of the Dodo; facing its demise due to growing human pressures and exploitation. However, In November 2006 the National Director for the Peregrine Fund’s Madagascar Project, Lily-Arison Rene de Roland, and field biologist Thé Seing Sam were conducting bird surveys in a remote area of Northern Madagascar when they spotted a group of Aythya innotata on a 28 ha volcanic lake.
The lake, known as Red Lake, and the surrounding area, is part of the central high plateau region. The lake is formed in a volcanic depression and cloaked with primary forest around its bowl and grassland forest at the rim. There is a narrow band of reeds about 15 metres deep between the lake and the forest edge. It is suspected that this population had remained at this site for many years because hunting did not occur and it received little disturbance from man. There were no introduced fish species and a small band of reeds provided sufficient nesting habitat. A lack of avifaunal surveys in the region, and with most surveys for the species being concentrated on Lake Alaotra, meant that this population had taken longer to discover in their isolated location.
Similar lakes in the region, and those between Lake Alaotra and the site of rediscovery, may have been modified by man making them unsuitable breeding habitats for the ducks. It is possible that some populations have yet to be discovered and that some populations have been extirpated through hunting. Red Lake is far from Lake Alaotra but is located in a former wetland basin, much like Lake Alaotra and those elsewhere on the Madagascan central plateau. In early December 2006 Glyn Young from the Durrell Wildlife Conservation Trust joined Lily-Arison Rene de Roland and Thé Seing Sam and revisited the lake to undertake a survey on the duck population. From the results the global population was estimated at between 20-25 individuals. Another survey covered surrounding lakes in the area but revealed no further ‘lost’ populations. This highlighted the importance of a rapid species recovery effort with an emphasis on how best to make sure that a random event could not wipe out the remaining population.
It was decided that an in situ captive breeding program to build up the population for future release onto suitable lakes was the best course of action. Glyn Young and Lance Woolaver (Durrell), Peter Cranswick and Nigel Jarret (WWT), Lily-Arison Rene de Roland (The Peregrine Fund) and government officials from Eaux et Forets collaborated in July 2009 to begin planning the project. News that the ducklings from 2008 had not survived to adulthood stressed the urgency of the situation. It was unclear why the young did not survive but it may have been due to predation from the endangered Madagascar Harrier Polyboroides radiatus and/or due to the six females being so badly harassed by the males that they were unable to properly care for their young. Recent research has shown that a lack of availability of food was the cause. The population was persisting in a lake with very steep sides, without areas of shallow water in which to dive down for submerged vegetation and invertebrate. Put simply, the ducklings were starving to death.
In October the team returned to the lake at night. They set up camp and erected a large tent for the incubators. At dawn the team rowed into the marsh and very carefully collected a clutch of nine eggs. These were transferred to the incubator and almost immediately a total of eight chicks hatched. Following the success of the first clutch a further two clutches were extracted. A clutch of nine eggs hatched and due to the onset of rain, a second clutch of seven, that were a week from hatching, were removed from the nest and placed in an incubator. They were then transported back to the temporary holding facility at the hotel. Glyn Young (Durrell) notes; “They could not have been easier to transport and our fears about their willingness to travel long bumpy roads was unnecessary”. The global population of Madagascar Pochard had been doubled. The next step was to build a specially designed breeding facility for the long term conservation of the species.
In 2010 the funding was obtained and the breeding centre was constructed at a suitable site in a town called Antsohihy, within the same region as the lake of rediscovery. The land is government owned and was leased free of charge. The site is situated on a main road used by tourists and the surrounding wetland provides the potential to build a visitor centre to increase awareness of the project and to promote wildlife conservation to schools, the public and tourists. The facility itself is not open to tourists to avoid habituation of the captive ducks to humans. The design of the centre was based on facilities at WWT Slimbridge in the UK. A few modifications were needed due to the nature of the local environment and climate being so different in Madagascar. For example, air conditioning and protection against mosquitoes for the ducklings was necessary. Scientists with experience in captive breeding of wildfowl are regularly sent out from equivalent UK based facilities at Durrell and WWT to care for the captive population.
The Peregrine Fund has been promoting the project within local communities and coupled with permanent guards, disturbance at the lake has decreased since the rediscovery. In early April this year the captive population successfully produced 18 ducklings making global news and bringing the world population to approximately 60 individuals. Scientists are currently studying the wild population to understand their ecology in order to identify suitable sites for reintroduction in the years to come.
The story of the Madagascar Pochard recovery program highlights the importance of human intervention when dealing with critically endangered populations. Unfortunately stories like this are likely to become more and more common as remaining endangered species populations become ever smaller and closer to extinction. We can certainly use the Madagascar Pochard project as a benchmark for future efforts in avian protection and hopefully continue to be successful in saving species from the brink of extinction as we gain experience and knowledge in this crucially important field of conservation.