Migratory Bird Corridor

The corridor supports at least 20 boreal migratory bird species, which breed in the northern hemisphere, along with seven other Neotropical migratory species, in addition to significant resident bird diversity. Among them, the Hudsonian godwit (Limosa haemastica) stands out: this wetland system supports approximately 99% of the population that breeds in Alaska and migrates along the Pacific Flyway, making the Maullín–Calbuco–Coihuín/Chamiza–Chiloé corridor a critical area for the conservation of this migratory population.

Birds do not use these wetlands as isolated units. They move among them according to tides, food availability, environmental conditions, and levels of disturbance. Their conservation therefore requires maintaining a functional network of connected sites across the Maullín, Calbuco, Coihuín-Chamiza, and Chiloé marine wetland system, capable of sustaining the birds through the different stages of their annual cycle.

Maullín, Coihuín–Chamiza, and the eastern bays of Chiloé form one of the main concentration systems for this species in South America. Within this network, Curaco de Vélez can host, in some years, more than a quarter of the Alaska-breeding Hudsonian godwit population, while other wetlands in the corridor serve complementary roles as feeding, resting, and shelter areas.

The corridor is also used by the whimbrel (Numenius phaeopus), along with sandpipers, plovers, and other migratory birds that depend on beaches, estuaries, salt marshes, and intertidal flats during their movements. They are joined by resident species such as the American oystercatcher, the black-necked swan, the flightless steamer duck, and numerous waterbirds.

During fall and winter, the Chilean flamingo (Phoenicopterus chilensis) becomes another of the corridor's key species. Large flocks use the shallow waters and intertidal flats of different coastal wetlands, moving among them in response to tides, food availability, wind, and other environmental conditions. Their presence also reflects the connectivity between inland and marine environments in southern Chile.

Maullín River Wetlands

The Maullín River Wetlands Nature Sanctuary protects approximately 8,194 hectares of rivers, flooded forests, salt marshes, estuaries, beaches, and intertidal flats. Sectors such as La Pasada, Lepihue, Amortajado, and Quenuir hold significant populations of migratory shorebirds, flamingos, swans, and other waterbirds. Part of the system is recognized as a Site of Regional Importance within the Western Hemisphere Shorebird Reserve Network (WHSRN), mainly for its importance to the Hudsonian godwit.

Coihuín–Chamiza

Located at the mouth of the Chamiza River and the Reloncaví Sound, Coihuín–Chamiza covers approximately 1,765 hectares of estuary, shallow waters, and extensive intertidal flats. At low tide, large areas are exposed and used by thousands of birds to feed, including Hudsonian godwits, whimbrels, and Chilean flamingos. The Coihuín Marine Wetland is recognized as a Site of International Importance within WHSRN.

Curaco de Vélez Bay Wetland Natural Monument

On the northern coast of Quinchao Island, the Curaco de Vélez Bay Wetland Natural Monument protects 59.7 hectares of intertidal flats, salt marshes, beaches, and estuarine environments. It is one of the main feeding and resting sites for the Hudsonian godwit in Chiloé, and is also home to black-necked swans, flamingos, whimbrels, and numerous waterbirds. It is part of the Eastern Chiloé Wetlands Site of Hemispheric Importance within WHSRN.

Bahía de Quinchao Wetland Natural Monument

The Bahía de Quinchao Wetland Natural Monument protects 102.8 hectares of intertidal flats, beaches, salt marshes, and coastal environments on the eastern coast of Quinchao Island. It is used by migratory birds such as the Hudsonian godwit and by Chilean flamingos, and is also one of the main breeding sites for the American oystercatcher on Quinchao Island. It, too, is part of the Eastern Chiloé Wetlands Site of Hemispheric Importance within WHSRN.

Together, these designations bring some of the corridor's main wetlands into a continental network of sites essential to the conservation of the Americas' migratory shorebirds.

FCM also takes part in individual capture and marking initiatives, using bands and visible flags, which make it possible to study movements, site fidelity, and connections between locations used by the same birds along their migratory routes. The information gathered has provided the basis for scientific publications, technical documents, protection proposals, management instruments, and concrete conservation measures.

This applied science guides actions such as protecting feeding, resting, and breeding areas, habitat management, nest monitoring, signage installation, and the regulation of public use. It also helps identify and reduce threats such as dogs, vehicle traffic, human disturbance, transformation of the coastline, and habitat loss.

Actions include environmental education, training of local leaders and guides, promotion of birdwatching tourism, signage installation, participatory development of management instruments, and strengthening of governance spaces. This approach seeks to reduce threats to birds while recognizing that wetlands sustain traditional activities, local identity, and development opportunities linked to natural heritage.

Citizen science is also part of this strategy. Since 2022, FCM and the Chilean Network of Bird and Wildlife Observers (ROC) have run Zarapitón, an initiative of coordinated counts that helps track the distribution and abundance of the Hudsonian godwit, the whimbrel, and other shorebirds, while strengthening the participation of observers and local communities in their conservation.

For Fundación Conservación Marina, the challenge is to move from conserving individual wetlands toward protecting the Maullín–Calbuco–Coihuín/Chamiza–Chiloé Migratory Bird Corridor, maintaining the ecological quality and connectivity of the coastal environments that allow thousands of birds to complete their migratory cycles.

Conserving this corridor also represents a responsibility of hemispheric scope: protecting these wetlands means directly contributing to the conservation of bird populations that connect northern Patagonia with much of the Americas.