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Scientists argue the case for large-scale marine protected areas

Posted on 17 April 2018

Large-scale marine protected areas (LSMPAs) are a vital component in the battle to protect the world’s oceans from exploitation, a group of international scientists argue today.

Marine protected areas aim to safeguard biodiversity and ecosystems.

The review, led by researchers from the University of York, concluded that as human impacts on the oceans grows, the value of LSMPAs for conservation will also increase.

Marine protected areas (MPAs) are designated areas in the world’s oceans where human activities are restricted, safeguarding biodiversity and ecosystems.

To date, there are around 13,000 MPAs worldwide with a median size of approximately 2.5 square kilometers. 


Recently, there has been interest in designating LSMPAs, but they have faced criticisms, including concerns over enforcement, possible reduction in seafood supplies and their effectiveness in protecting ecosystems.

However, the authors of the review, who include 14 scientists from 11 universities and non-governmental agencies from around the world, argue that LSMPAs are an important component of diversified ocean management.

Currently, only 6.6 per cent of the world’s ocean is covered by any protected area – large or small.

The globally adopted conservation target for ocean conservation is to have at least 10 per cent protected by 2020. The International Union for the Conservation of Nature recommended in 2016 safeguarding 30 per cent of the ocean in strongly of fully protected areas.

Healthy Ocean

Dr Bethan O'Leary, Research Associate in the Environment Department at the University of York, said: “We are racing to meet the global commitments for ocean conservation, and large-scale marine protected areas are helping us do this.

“But there have been recurring themes in the pushback against LSMPAs. We wanted to rationally and rigorously dissect those arguments because we need to make sure that we meet our conservation targets and ambitions in a meaningful way in order to ensure a healthy and resilient ocean for the future.

“The conclusion we came to in this research was that those criticisms that have evidence to support them, things like difficulty of enforcement and ability to protect ecosystems against stressors like pollution or climate change, are in no way special in regards to LSMPAs and can be applied to all kinds of environmental management.

Human Impacts

“In some instances, we found evidence contrary to the criticism, as with the ability for LSMPAs to help solve obvious conservation problems, like overfishing or protecting mobile species.”

Among some of the benefits highlighted through this analysis were the ability of LSMPAs to represent entire ecosystems, protect against human impacts, offer opportunities to improve food security and stabilise catch levels for fishers, promote ecosystem resilience to climate change, and their cost effective nature.

Dr O’Leary added: “The biggest takeaway from this study is that there is not one single answer. We need a diverse set of tools to protect and rebuild the health of our oceans from the growing human impacts they are facing. We need every tool available to ensure a sustainable future and secure our future on this planet.”

The analysis is published in the journal BioScience.

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About this research

This review was carried out by Dr Bethan O'Leary from the Environment Department . Explore our research