Blog by Dr Graeme Buchanan, Principal Conservation Scientist, RSPB Centre fo Conservation Science

The recent IPBESS report highlighted to all the serious state of biodiversity globally. It set out in stark numbers the pressures that nature faces, and highlighted the need for urgent action by all. Importantly the report stressed that if we do act quickly and appropriately our impact on biodiversity can be minimised. The majority of the world's governments have already signed up to a shared vision for biodiversity conservation in the shape of the Convention on Biological Diversity’s (CDB) Aichi Targets. These widely discussed targets were agreed in 2010 with the aim of meeting them by 2020 at the latest. These targets can be seen as how the world’s governments have agreed to value restore, and wisely use biodiversity.

Lizzy Green recently discussed the analysis on which she led that found a link between progress to these targets and the way they are frames, specifically how SMART they were. Smarter targets beget greater progress. One of the targets to which most progress was agreed to have been made was target 11, which relates to protection of the terrestrial and marine environments. 

Specifically it requires that “By 2020, at least 17% of terrestrial and inland waters and 10% of coastal and marine areas, especially areas of particular importance for biodiversity are conserved through effectively and equitably managed protected areas and other effective area-based conservation measures”. Protected areas have been the cornerstone of global conservation form many years. These are the sites that benefit from some form of legal designation and protection. In the UK these include the SPA, SSSI and SPA networks that are valuable to UK wildlife. But the text “other effective area-based conservation measures”, or OECMs, reflects the recognition that legal designation may not always be the only way to protect sites. After much discussion a formal definition of what OECMs are was agreed in 2018.

Specifically, in 2018, CDB defined an OECM is “a geographically defined area other than a Protected Area, which is governed and managed in ways that achieve  positive and sustained long-term outcomes for the in situ conservation of biodiversity with associated ecosystem functions and services and where applicable, cultural, spiritual, socio–economic, and other locally relevant values.”

This means that biological conservation does not need to be the primary objective of the site. Rather, OECMs are defined by what they deliver for conservation. But what do they deliver for conservation? The process of OECM identification is on going but some potential OECMs have been suggested. For example, Scapa Flow in Orkney could be an OECM because, while it is protected for the cultural value of the scuttled ships on the seabed, the protection afforded has resulted in exceptional marine life.

Photo:  Scapa Flow in Orkney could be an OECM because, while it is protected for the cultural value of the scuttled ships on the seabed, the protection afforded has resulted in exceptional marine life. Photo by: Gregory J Kingsley [CC BY-SA 3.0 (]

Conservation is global, and a recent global collaboration funded by the CCI Collaborative Fund for Conservation,  that utilised the unique BirdLife partnership (RSPB is the UK BirdLife partner) around the globe has looked into this question. The partnership facilitated the collation of information on the coverage of OECMs of Key Biodiversity Areas (KBAs) from 10 countries around the world. KBAs are sites of importance for the global persistence of biodiversity, identified using quantitative criteria. As such they can be seen as representing the most important sites for biodiversity around the globe. These are the most important sites to conserve. There were slightly over 2000 KBAs in the 10 countries that contributed to the study, of which around a third had a substantial overlap with protected areas. Of the remaining number, information was available on whether or not they fell within an OECM for 740 of them, of which 76% overlapped with an OECM. This highlighted for the first time the extent to which OECMs could potentially play a role in the protection of the most important sites for biodiversity around the world.

Subsequent assessment of how well these OECMs deliver for conservation was less clear-cut. While the KBAs overlapping protected area were in a better state than other KBAs, there was no detectable advantage to the KBA of overlapping an OECM. There was no difference in the number of pressures that the KBA faced. And the conservation response on sites, while again higher on protected KBAs, did not differ between KBAs that were and were not in OECMs. The rate of tree loss on KBAs that were important for forest species followed suit, with formal protection reducing loss, but no apparent advantage being derived from coverage by OECMs.

This all suggests that OECMs, while having a high potential to help conserve KBAs, are not having a detectable effect. But there could be some benefit from OECMs, albeit based on opinion rather than hard data. There was a feeling among some who provided data that conservation of KBAs lacking both protected area status and an existing potential OECM would usually be better achieved through an OECM than a protected area. The fact that so many sites of recognised conservation importance survive outside protected areas in areas of high human population density suggest a degree of effectiveness of OECMs. The study concluded by noting that almost half of the potential OECMs identified by this project are government-managed. This suggests the future of OECMs lies largely in the hands of those responsible for meeting the Aichi targets by 2020, and negotiating and agreeing what happens within the Convention on Biological Diversity after 2020.

 Full reference: Donald PF, Buchanan GM,Balmford A, et al. The prevalence, characteristics andeffectiveness of Aichi Target 11′s “other effective area-based conservation measures” (OECMs) in Key Bio-diversity Areas.Conservation Letters. 2019;e12659.