By Mary Collins, IUCN WCPA Connectivity Conservation Specialist Group’s Marine Connectivity Working Group (MCWG) Graduate Associate, hosted by the Center for Large Landscape Conservation

Context and challenge 

Figure 1. The East Atlantic Flyway (red), which many migratory seabirds use to travel between breeding territory (orange), and significant staging and wintering sites (blue dots) (van Roomen et al. 2017).

The East Atlantic Flyway is a flight path traveled by millions of seabirds as they migrate between arctic breeding grounds and staging and wintering sites scattered along the eastern shores of the Atlantic Ocean and adjacent seas (figure 1). Seabirds depend on these locations for nesting, feeding, and overwintering, hence, these stepping-stone habitat provisions and conditions can affect bird numbers and their conservation status. In 2014, it was estimated that 24 million waterbirds used the East Atlantic Flyway (van Roomen et al. 2017). Seabirds are adapted to and depend on the marine environment for survival and are thus considered to be included into marine connectivity conservation considerations. 

The Wadden Sea is an important stepping stone for seabirds traveling along this flyway. It is one of the world’s largest uninterrupted systems of transitional intertidal habitats encompassing tidal channels, sandy shoals, sea-grass meadows, mussel beds, sandbars, mudflats, salt marshes, estuaries, beaches, and dunes (UNESCO). It spans 500km (310 miles) along German, Dutch, and Danish coasts (figure 2). Recognized as a UNESCO World Heritage property in 2010, the area is of high importance for seabirds by providing food provisions and islands that lack mammalian predators and human disturbance. According to the Ramsar Convention on Wetlands, at least 52 populations of 41 migratory waterbird species depend on the Wadden Sea as a stepping stone or overwintering destination along the East Atlantic Flyway (Wadden Sea- World Heritage). Ten to 12 million birds pass through the Wadden Sea each year, as part of the East Atlantic Flyway (UNESCO).

Figure 2. Wadden Sea World Heritage property, spanning Danish, Dutch, and German waters with habitat types marked by color (UNESCO).

Figure 3. Banc d’Arguin National Park and World Heritage property in Mauritania, with habitat types marked by color (Araujo et al. 2016).

Flying south along the East Atlantic Flyway, Banc d’Arguin National Park is the next prominent place essential for migratory seabird success. Located on the west coast of Mauritania in western Africa, the park includes unique coastal conditions that connect the harsh desert and dunes to rich marine environments in the Bay of Arguin (figure 3). Also a UNESCO World Heritage property, it serves as an important resting, feeding and breeding ground for migratory seabirds (UNESCO).

The two sites, Wadden Sea and Banc d’Arguin, are inextricably tied together due to the connected populations of migratory birds that depend on each for essential life cycle needs and food required to complete flight journeys. However, climate change and human impacts threaten ecological connectivity along the East Atlantic Flyway. Changes are documented to affect some seabird populations in disproportionate amounts, depending largely on food guilds. For example, benthivores, particularly shellfish-eating populations, are generally declining in numbers, while herbivores that depend on salt marshes and agricultural areas are generally increasing (Van Roomen et al. 2017). As climate change impacts continue and land-uses change, East Atlantic Flyway seabird diversity and richness is threatened. 

Approach

Taking ecological connectivity into consideration, where migratory species’ survival is closely tied to the habitat conditions along a migratory route, is essential to successful conservation outputs. Conserving, and where needed, restoring, ecological connectivity that supports migratory bird flyways is feasible, despite large distances between locations. 

Protecting the important migratory bird nesting, feeding, and overwintering locations requires international collaboration. Recognizing this, the two World Heritage properties, Banc d’Arguin National Park and the Wadden Sea, together signed a Memorandum of Understanding (MOU) in 2014 for exchanging best practices, conservation techniques, and cooperating on bird counting and monitoring. Signatory Parties include Germany, Mauritania, and The Netherlands (UNESCO). Aside from the benefits provided to migratory wildlife brought by aligned management, such agreements also provide advantages for seeking financial support and long-term staff resources (Bostelmann, 2017). Since the agreement was put into effect, bilateral visits allow managers and scientists to progress development of a joint action plan and to assess bird population dynamics using like indicators. Further, the action contributed to other collaborations among non-bordering States over flyway connectivity conservation, like the Wadden Sea Flyway Initiative and The Flyway Vision (van Roomen et al. 2017; WSFI). 

Results 

A formal collaboration among non-bordering States for conservation of marine migratory populations, like seabirds, is feasible and even provides advantages to the governing bodies through shared resources and knowledge. The MOU signed by Wadden Sea and Banc d’Arguin National Park UNESCO World Heritage properties exhibits a commitment to connectivity conservation, influencing more formal collaborations for migratory populations that don’t respect jurisdictional borders. UNESCO highlighted the agreement as a best practice for migratory species conservation in their 2015 guide for best practices ( Douvere, 2015). Further research is needed to determine whether this MOU is used as a model for other flyway or marine migratory collaboration. 

While the collection and availability of flyway population and habitat condition trends have improved as a result of the collaboration, improvements are necessary for better informing management. The quality of the data, for example, will be improved with increased training that teaches scientists to collect data points using identical methods. The quantity of data is also identified as an area for improvement, as increasing the quantity of data collected will increase certainty in population trends. These improvements made at each site will also help to identify whether trends are site-specific vs. present throughout the flyway, indicating where preservation expansion, altered management, or restoration will be most effective (van Roomen et al. 2017). Additionally, scientists more frequently travel from the Wadden Sea to Banc d’Arguin, so more collaboration in the reverse direction is needed in order to provide managers and scientists the same amount of understanding about the connected systems (Bostelmann, 2017). 

References

https://whc.unesco.org/en/news/2180 

Araujo A., Campredon P. 2016. Banc d’Arguin (Mauritania). In: Finlayson C., Milton G., Prentice R., Davidson N. (eds) The Wetland Book. Springer, Dordrecht. https://doi.org/10.1007/978-94-007-6173-5_154-1

Bostelmann, A. 2017. East Atlantic Flyway partnership for the conservation of tidal flat ecosystems Banc d’Arguin – Wadden Sea. Panorama. https://panorama.solutions/en/solution/east-atlantic-flyway-partnership-conservation-tidal-flat-ecosystems-banc-darguin-wadden-sea. 

Douvere, F. 2015. World heritage marine sites: managing effectively the world’s most iconic marine protected areas;best practice guide. United Nations Educational, Scientific and Cultural Organization, 7, place de Fontenoy, 75352 Paris 07 SP, France. ISBN 978-92-3-100106-2. Accessed through https://unesdoc.unesco.org/ark:/48223/pf0000235316. 

United Nations Educational, Scientific, and Cultural Organization (UNESCO). 2015. World Heritage Marine Sites; Managing effectively the world’s most iconic Marine Protected Areas. ISBN 978-92-3-100106-2. https://unesdoc.unesco.org/ark:/48223/pf0000235316. 

van Roomen M., van Turnhout C., Blew J., Koffijberg K., Nagy S., Citegetse G. & Foppen R. 2017. East Atlantic Flyway. In: Wadden Sea Quality Status Report 2017. Eds.: Kloepper S. et al., Common Wadden Sea Secretariat, Wilhelmshaven, Germany. qsr.waddensea-worldheritage.org/reports/east-atlantic-flyway 

Wadden Sea Flyway Initiative (WSFI). https://caff.is/dm/ambi-presentations-public/ambi-rovaniemi-october-2018/1170-wadden-sea-flyway-initiative-wsfi/file