KEY NORTH AMERICAN MIGRATION SITES FOR
Red Knots & Semipalmated Sandpipers

Bahía de Todos Santos

Country: Mexico

Region: Baja California,

Nearest city/town: Ensenada

Site: Bahía de Todos Santos

Species/Sub-species: REKN-roselaari

Total biogeographic population: 21,7701

Count Method: Maximum day count

Count: 9792

% biogeographic pop. at site: 4.50

Season (primarily): Winter

Site recognition: WHSRN Ramsar IBA

Site recognition (other): World Surfing Reserve, Biodiversity Priority Conservation Area by CONABIO.

Site description: Using the Ramsar Classification System for Wetland Type, the site's habitat characteristics are coastal, including marine subtidal aquatic beds, rocky marine shores (which include rocky offshore islands and sea cliffs); sand, shingle or pebble shores (which include sand bars, spits and sandy islets, and dune systems); intertidal mud, sand or salt flats; and intertidal marshes (which include salt marshes, salt meadows, saltings, raised salt marshes, and tidal brackish and freshwater marshes). Two rocky islands are in the Bay. The bay includes Sandy beach, rocky shoreline, sand dunes and barrier beach; and a coastal wetland includes intertidal marshes, mud and sand flats, and eelgrass beds. Land ownership is a mix of municipal, state and federal lands; private properties; and community owned lands (ejidos). There is a Management Plan for the Estero de Punta Banda Ramsar Site. The Migratory Shorebird Project has been monitoring shorebirds and their habitats since 2011. Several postgraduate theses on shorebirds and other waterbirds are available. Work that was underway in 2016 includes the Migratory Shorebird Project, and wintering shorebird monitoring and environmental education5.

Known threats: Energy production is a threat to the site in the form of mining and quarrying and oil and gas drilling resulting in land use change. Rock and sand mining for construction is causing sedimentation in the Estero de Punta Banda wetland. Dams and water management use is also a land use change threat to the site in terms of natural systems modification. The main environmental impacts to the area occurred in the 1980s, when the installation of an assembly for plant oil drilling platforms began in the southwest corner of the estuary. The work was interrupted in 1986, possibly due to problems in the oil market worldwide. The dam constructed for the assembly changed 45 ha of the estuary for which 21 ha were composed of marsh vegetation. Housing and urban areas represent a residential and commercial development threat to the site. Housing development since the 1980s too has impacted 70% of the dunes.  There are also pollution threats to the site due to domestic and urban waste water and agricultural effluents and practices. Lack of services, especially the absence of sewage and wastewater treatment, directly affects the quality of water within the estuary. Agricultural activities carried out in the estuary surrounding areas, mainly in the Valley of Maneadero, have generated primary and secondary impacts, mostly associated with the contamination of soil and subsoil and the abatement of aquifers. The use of agrochemicals, which are transported by surface runoff or tidal currents to the main channel, and which have been determined in several studies, as well as overfishing and pollution of groundwater in the area, are other impacts caused by agricultural activity. The habitat effects of fishing and harvesting aquatic resources is a low threat to the site. This includes commercial (sardine and anchovy) and subsistence (artisanal) fisheries, harvesting of shellfish, and fish and mussel aquaculture. The impact on shorebirds is unknown, but probably not significant. In terms of the physical alteration of the site, there is a high threat of invasive plants. Exotic plants Carpobrotus edulis and C. equilaterus, and Mesembryanthemum crystallinum, of fast and aggressive growth, have been displacing native vegetation of the area. Control of these invasive plants is a priority and requires immediate attention.6

Notes: The Red Knots are presumed roselaari but not confirmed. The boundary of the site follows the IBA delimitation 3. Ramsar Site #1604, IBA, 6ta.

Sources: 1https://www.manomet.org/newsletter/scientific-expedition-mexico-discovers-shorebird-wintering-site 2 eBird (Marshall Iliff December 19, 2002). 3Pronatura and CONABIO. 2015. Áreas Importantes para la Conservación de las Aves (kml file). Pronatura Sur, Chiapas, México. See also http://www.imipens.org/IMIP_files/PDUCP-E2030-abreviado.pdf 4http://www.imipens.org/IMIP_files/PDUCP-E2030-abreviado.pdf 5http://www.migratoryshorebirdproject.org/uploads/documents/MSP_Handout_English_final.pdf 6Ramsar management Plan for Estero Punta Banda: http://ramsar.conanp.gob.mx/docs/sitios/lineamientos_instrumentos/ESTERO_PUNTA_BANDA.pdf