Why do MPAs need species distribution modelling based on wildlife monitoring?

A model to create an integrated network of MPAs for migratory species.

Photo credit: Sebastian Pena Lambarri on Unsplash

Marine Protected Areas: why do we need them?

Marine Protected Areas, known as MPAs, are one of the most critical conservation and sustainability tools available to scientists. One of their primary functions is regulating human activities, such as fishing and tourism, to address several of the pressures on marine biodiversity and maintain healthy ecosystems. Proper management and implementation of MPAs, by protecting habitats and species, enable marine ecosystems to continue providing essential benefits to people.

Collectively known as ecosystem services, the contributions deriving from functioning ecosystems are several, ranging from food security to coastal protection from storms and erosion. Ecosystem services are essential to human survival and well-being — for example, 3.1 billion people rely on oceans for almost 20% of their animal protein intake. In terms of economic value, coastal habitats provide ecosystem services worth approximately $50 trillion per year(1), while deep-sea ecosystems provide services worth around $267 billion per year(2).

Definition of a Marine Protected Area (3) and ecosystem services provided by the MPAs (4) (graphic by: Alessandra Sellini)

The role of MPAs in marine conservation is especially crucial if we consider the ongoing, and intertwined, climate and biodiversity crisis(5).

Coastal ecosystems, such as mangroves, salt marshes, and seagrasses, are effective carbon sinks (also known as “blue carbon” ecosystems). Despite covering around 2% of the total ocean area, they account for approximately 50% of the total carbon sequestered in ocean sediments(6). Mangroves, along with reefs, also protect the costs from extreme weather events(6), likely to increase as a consequence of the rising temperatures(7).

Of the marine species assessed by the IUCN, around 9% are threatened with extinction, classified either as Critically Endangered (CR), Endangered (EN), or Vulnerable (VU)(8). Among those, some groups appear more vulnerable. By 2020, 77% of oceanic shark and ray species were threatened with an elevated risk of extinction(5), and 33% of corals were threatened with extinction(9).

Number of marine species threatened with extinction (IUCN) and percentages of endangered species for each main marine taxonomic group (8) (graphic by: Alessandra Sellini)

Despite their importance, and that around 60% of major marine ecosystems are degraded or used unsustainably(10), only 7.68% of the oceans worldwide are designated as protected areas. This is far cry from what the experts agree would be necessary to achieve a sustainable future: 30% of the oceans protected by 2030.

The Sustainable Development Goals (SDGs) established by the United Nations (UN) supported by the implementation of MPAs (image credit: UN) (graphic by: Alessandra Sellini)

From complex systems to interpretable insights

Effectively establishing and managing an MPA is a challenging task.

Good practices for adequate MPAs, among others, include: developing policies addressing the full range of pressures on the biodiversity and the ecosystem, drafting management and monitoring protocols, deploying strategies for compliance and enforcement, and estimating costs and benefits(3). All practices depend on a clear understanding of the state and pressures of the area.

However, Oceans are multidimensional and complex systems. From the fluctuations of environmental variables across seasons to intra- and inter-species interactions, developing a deep understanding of ecosystem dynamics requires extensive monitoring and data processing and interpretation.

Remote sensing technologies allow us to monitor almost real-time the various aspects of ocean biogeochemistry and animal movements, abundance, and distribution. Ecosystem models can then incorporate this large-scale, spatio-temporal data to describe processes and species interactions within a given area into one modelling framework. These models are widely used to understand ecosystem dynamics and predict and detect natural or anthropogenic changes over time(11).

“We define an ecosystem model as a model that describes the interactions between at least two ecosystem components (for example, a species or functional group), whereby the interactions are real ecological processes (for example, predation, dispersal or perturbations). […] These models were developed because ecologists needed to disentangle, and therefore predict, the outcomes of complex interactions between ecosystem components in a meaningful way.” (11)

Ecosystem modelling with Wildlife Tracker

The framework of Wildlife Tracker v0.4 provides the means for creating detailed ecosystem models. The software is capable of real-time geo-visualization for essential environmental features, such as oxygen concentration and primary productivity, and wildlife movements. By overlapping these layers of information, it is possible to obtain a snapshot of the interaction network of the area of interest and link environmental variables with species presence/absence.

The ecosystem models created within the framework of Wildlife Tracker can prove extremely useful for large-ranging and migratory species, whose conservation is extremely challenging. Species of cetaceans, sharks, rays and birds cross the waters of multiple countries to move between feeding and mating grounds, taking advantage of the most favourable conditions during each season. Therefore, their safeguard depends on an effective network of protected areas covering season-specific habitat(s), presuming both a spatial and a temporal dimension(12).

The importance of MPAs placement and quantity in a seasonal context (12) (graphic by: Alessandra Sellini)

In the next months, we’ll address this complex conservation issue by developing a model aimed at evaluating and improving the effectiveness of MPAs network for migratory marine species.

The model will incorporate the spatial and temporal dimensions involved in seasonality. It will include:

• Eco-geographical data: Sea Surface Temperature (SST), oxygen concentration, and chlorophyll concentration and their seasonal variations
• Metrics from satellite tags: daily travelled distances, time spent in protected areas, duration of stops with spatial-temporal parameters, season-specific activity space
• Human activities: fishing activities and their fluctuations across seasons

The developed ecosystem model will find application as a tool to assess the potential expansion of pre-existent MPAs to cover seasonal habitat(s) for endangered marine wildlife and improve the management of human activities within the MPA borders.

The architecture of an ecosystem model: input (biologging and environmental data; MPAs current delimitation and temporal series of ecogeographical variables) and output (ecological and conservation applications) (11) (graphic by: Alessandra Sellini)

Wildlife Tracker has a core mission: supporting marine conservation and marine spatial planning towards a more effective MPA demarcation and better government of wildlife protection.

Image credit: Wildlife Tracker. Based on Arturo Rivera from Unsplash

References

1. Costanza, R., De Groot, R., Sutton, P., Van der Ploeg, S., Anderson, S. J., Kubiszewski, I., … & Turner, R. K. (2014). Changes in the global value of ecosystem services. Global environmental change, 26, 152–158.
2. ​Ottaviani, D. (2020). Economic value of ecosystem services from the deep seas and the areas beyond national jurisdiction. FAO Fisheries and Aquaculture Circular №1210. Rome, FAO.
3. OECD (2016). Marine Protected Areas: Economics, Management and Effective Policy Mixes, OECD Publishing, Paris.
4. Barbier, E. B. (2017). Marine ecosystem services. Current Biology, 27(11), R507-R510.
5. WWF (2022) Living Planet Report 2022 — Building a nature-positive society. Almond, R.E.A., Grooten, M., Juffe Bignoli, D. & Petersen, T. (Eds). WWF, Gland, Switzerland.
6. Lecerf, M., Herr D., Thomas, T., Elverum, C., Delrieu, E. and Picourt, L. (2021). Coastal and marine ecosystems as Nature-based Solutions in new or updated Nationally Determined Contributions, Ocean & Climate Platform, Conservation International, IUCN, GIZ, Rare, The Nature Conservancy and WWF.
7. Stott, P. (2016). How climate change affects extreme weather events. Science, 352(6293), 1517–1518.
8. Luypaert, T., Hagan, J. G., McCarthy, M. L., & Poti, M. (2020). Status of marine biodiversity in the Anthropocene. In YOUMARES 9-The Oceans: Our research, our future (pp. 57–82). Springer, Cham.
9. IUCN. IUCN Red List 2017–2020 Report.
10. UNEP (2011). Towards a Green Economy: pathways to sustainable development and poverty eradication (a synthesis for policy makers), United Nations Environment Programme, Nairobi.
11. Geary, W. L., Bode, M., Doherty, T. S., Fulton, E. A., Nimmo, D. G., Tulloch, A. I., … & Ritchie, E. G. (2020). A guide to ecosystem models and their environmental applications. Nature Ecology & Evolution, 4(11), 1459–1471.
12. Lambert, C., Virgili, A., Pettex, E., Delavenne, J., Toison, V., Blanck, A., & Ridoux, V. (2017). Habitat modelling predictions highlight seasonal relevance of Marine Protected Areas for marine megafauna. Deep Sea Research Part II: Topical Studies in Oceanography, 141, 262–274.