Background Around 100,000 birds winter every year in the Tagus Estuary, one of the most important European wetlands. During the migration period, this number rises to 120,000. The region is located in the transition area between southern Europe and North Africa on the East Atlantic Flyway. An important SPA comprises a set of valuable habitats, mainly mudflats, sandflats and Mediterranean and thermo-Atlantic halophilous scrubs, where birds shelter and feed. The Samouco saltpan complex is a 360ha area of artificial lagoons, river branches and abandoned salt pans within this SPA. Although small, it represents an important portion of the available feeding and shelter habitats, which are used by around 5% of the wintering birds of the estuary, namely Egretta garzetta, Phoenicopterus rubber, Himantopus himantopus, Recurvirostra avosetta, Sterna albifrons, Pluvialis squatarola, Calidris minuta, C. alpina, Tringa tetanus, Limosa limosa and L. lapponica. Difficulties in controlling water levels inside 70% of the area have led to reduced food and shelter availability, while predation and exotic vegetation have caused a reduction of the breeding habitat quality for some wader species. Objectives The project aimed to increase the number of waders using the salines during the migrations of 30 to 40% of breeding Sterna albifrons and 30% of Himantopus himantopus, and raising the breeding success of at least 50% of waders that breed in the salines. These goals would be realised through the adaptation of the salines’ morphology so that water levels can be effectively controlled. Pipes and sluices would need to be installed, excavations undertaken and the bottom of tanks levelled. The project also foresaw the installation of floating platforms and the creation of artificial islands inside the tanks, where the birds will be able to nest undisturbed. A dissemination campaign would include the production of leaflets for schools and visitors, brochures, a video, a webpage and a map, and the organisation of a seminar. Results The project encountered difficulties as a result of errors in the prediction of cost. The failure to carry out a key component of the project – modification of the salt pans – had negative repercussions for all the other planned actions. Though salt production is a general problem for the conservation of birds species that depend on the target habitat, future interventions at the Samouco saltpans, as well as in other similar systems and SPA, namely at Sado estuary, ‘Ria’ of Aveiro, ‘Ria’ Formosa and Castro Marim Saltmarshes, are still possible. As well as the cost constraints, the project was hampered by delays in decision making over the new legal status and working structure for the Fundação das Salinas do Samouco. The three-year project took place in a 360ha area included in the Tejo SPA and created five new jobs (two rural workers, two technicians and a biologist). The water level control measure and the maintenance of the islands and platforms will be continued after the end of the project. The annual monitoring will also continue under the supervision of a biologist and a co-ordinator.