The study makes use of advanced satellite transmitters that are placed on the birds that send signals on the location of the birds. Gaast’s journey took her from her breeding grounds in the Warkumerwaard, a former salt marsh west of Workum in the Netherlands, through the Cota Donana National Park in Spain and the Isla Cristina and Ayamonte marshes and Prado lagoon on the border between Portugal and Spain, Djoudj National Park in Senegal and Rio Geba Estuary, in Guinea Bissau ending up in the Inner Niger Delta in Mali.
To complete this journey Gaast had to make critical stops to rest and feed at some of most famous and critically internationally important wetlands along its migration in Europe and West Africa and provided excellent new information on the precise migratory strategy.
Inner Niger Delta, Mali
After spending about two months in the coastal wetlands in Guinea Bissau, Gaast flew eastwards to settle down in the vast inland freshwater floodplains of the Inner Niger Delta in late October. The Delta a major northern wintering site for the west European population of Blacktailed Godwit and millions of other waterbirds. Last week, the Dutch researchers informed Mr. Mori Diallo, Waterbird Officer of the Wetlands International – Mali Office that it appeared from the satellite tracking information, the movements of Gaast over the previous days did not appear to be normal and feared the bird may have died.
On 3rd December 2009, Mori organized a field team from the capital Mopti that travelled northwest into the vast floodplains to investigate the issue. Aided by a satellite location, they arrived at the precise spot where Gaast was last reported. Here they found remains of the wings of a godwit in the net but they were unable to find the transmitter. After some clever and detailed enquiries with the village leaders of Bourde, the closest fishing village, they were finally provided with the transmitter a day later and were informed that the bird had been found dead in a fishing trap.
Food needs for local population
While this bird may have been died in a fish trap, the targeted trapping of wild waterbird species for local consumption and sale remains a major means of sustaining the food needs of many local people. It is estimated that tens of thousands of waterbirds are harvested annually in the Inner Niger Delta and the intensity of harvest varies depending on the water level. The management and conservation of these long distance migratory species thus depends on finding innovate ways to ensure the basic protein needs of the local people can be met.
The Blacktailed Godwit occurs from across Eurasia, Africa and Australasia. Its population is rapidly declining in parts of its range owing to changes in agricultural practices, hunting and other threats. As a result, the status of the species has been raised to Near Threatened in the Global Red List of Threatened Species of IUCN. A species conservation action plan recently developed under the African-Eurasian Waterbird Agreement provides a framework to promote the management of the species and its critical habitats.
Known as “grutto” in Dutch, national breeding population is also declining and considered a species of special national concern. The Dutch Agricultural policy provides large subsidies to farmers to manage agricultural lands and grasslands to enable the birds to breed successfully as part of a national strategy to increase the population.
Wetlands International is actively engaged in a development and implementation of a long-term programme to increase our understanding of the Inner Niger Delta system and to find ways to sustainably manage the area, its biodiversity and livelihoods of people. The work is being undertaken with a range of national agencies, the Ramsar Convention and African-Eurasian Waterbird Agreement, NGOs and like-minded organisations.
It has successfully piloted a project under the biorights approach to reduce the hunting of a major migratory species of Palearctic duck, the Gargeney Anas querquedula by supporting the local communities to develop alternative livelihood options. Such approaches may provide a solution to reduce the dependence of these communities on Palearctic and Afrotropical waterbirds. We are building up critical information on the importance and linkage of wetlands for the Purple Heron and other waterbirds that migrate between the Netherlands and West Africa, through the Follow The Bird! programme.
For more information:
On our Inner Niger Delta work
On the migration of the Black-tailed Godwit, including Gaast (Vogelbescherming NL)
The Follow The Bird! programme
On satellite transmitters