Nations of the world will meet in May to negotiate a new Global Biodiversity Framework (GBF) under the Convention on Biological Diversity. It’s a big deal because this framework will define global aspirations for protecting species, ensuring benefits from ecosystem services, reducing pressures on nature, and making biodiversity governance more sustainable.

Part of the post-2020 GBF includes explicit targets for what we hope to achieve in the next decade. Devising these targets is an arduous process, where every word is chosen carefully after hours of negotiation. Using the word ‘and’ instead of ‘or’ could cost millions of dollars in government budgets. Even worse, the wrong word could potentially lead to the permanent extinction of species that have been around for millions of years.

It makes sense that at least one of the targets for the post-2020 GBF should focus on ecosystems. After all, no plant or animal can exist in isolation. Now, while I won’t be so brash to propose my own ecosystem targets, I would like to point out three pitfalls that should be avoided once government negotiators come together at the next COP meeting.

Pitfall 1: Conflating the surface area of land and sea with the surface area of habitat

It’s tempting to want to allocate a proportion of our globe for biodiversity. Such suggestions – like the Half-Earth Project – resonate with the general public and would be easy to measure using simple area calculations.

However, merely staking out an area on a map will not necessarily benefit plants and animals. A massive protected area in the Sahara will mean less for biodiversity than smaller protected areas in the Rift Valley, West African Forests, or the Cape Floristic Region. We need to focus on preserving areas that (a) are significant habitat for species and (b) are imperilled by human actions.

If the previous decade has taught us anything, it’s that humans are pretty good at meeting area targets, but we’re not nearly as good at protecting important ecosystems effectively.

Aichi Target 11 of the 2010-2010 Biodiversity Strategic Plan was made up of six components, yet we only met the components of area coverage of protected areas (green). The components related to protected area prioritisation, management, representation and connectivity were only partially met (yellow).

A post-2020 ecosystem target should explain clearly which ecosystems should be retained, where they should be prioritised, and how they should be managed.

Pitfall 2: Treating protected areas as the only form of conservation

Although protected areas are important for conservation, they are not the only way to preserve plants and animals. In fact, most species live outside of protected areas. If we have any hope of avoiding a sixth mass extinction, we need to figure out ways for plants an animals to survive alongside human activities.

This means that we should start seeing ecosystem conservation as a continuum. At one end are strict protected areas. At the other are high impact activities, like mining, industrial agriculture and cities. Everything in between ought to represent a gradient of human impact.

Ecosystem area-targets could represent this gradient of impact by setting three separate sub-targets: (i) a protection target, including (ii) other effective conservation measures (OECM), which are nested within (iii) an ecosystem retention target.

These targets could possibly be linked to the Red List of Ecosystems. For example, the strict protection targets might be designed to prevent ecosystems from becoming critically endangered (~10%); OECM could prevent species from becoming endangered (~30%); while retention targets could prevent ecosystems from being listed as vulnerable (~50%).

This would mean that half of all ecosystems should be retained, but they could still be used for low impact human activities.

Pitfall 3: Focusing on rates of change, rather than fixed retention thresholds

The first global Strategic Plan for biodiversity back in 2002 defined its mission as:

Parties commit themselves to a more effective and coherent implementation of the three objectives of the Convention, to achieve by 2010 a significant reduction of the current rate of biodiversity loss at the global, regional and national level as a contribution to poverty alleviation and to the benefit of all life on earth.

Rate-based targets have two major shortcomings. First, they imply that the targets for rare and unique ecosystems are the same as for widespread and common ecosystems. Second, they assume that a zero rate of loss is a desirable outcome.

Picture an ecosystem that is transformed, degraded and fragmented by agriculture. For 50 years, the extent of this ecosystem declines until only 10% remains. If we succeed in reducing the rate of loss to zero, the ecosystem is still only 10% of its original extent. How can that be considered a conservation success?

Compare this to a second ecosystem that declined to 90% of its original extent due to human activities. Should we restrict any further habitat conversion to maintain this idea of reducing the rate of loss?

While global frameworks have generally moved away from rate-based targets, there is a resurgence in the form of no net loss policies. But expecting no net loss for all ecosystems could result in significant biodiversity losses in the upcoming decades. Instead, we should probably consider linking rate-based targets to ecosystem retention targets: expecting restoration in threatened ecosystems and allowing for controlled loss in least threatened ecosystems.

Are we on the right track?

The zero draft of the post-2020 Global Biodiversity Framework includes the following targets:

Target 1. By 2030, [50%] of land and sea areas globally are under spatial planning addressing land/sea use change, retaining most of the existing intact and wilderness areas, and allow to restore [X%] of degraded freshwater, marine and terrestrial natural ecosystems and connectivity among them.

Target 2. By 2030, protect and conserve through well connected and effective system of protected areas and other effective area-based conservation measures at least 30 per cent of the planet with the focus on areas particularly important for biodiversity.

There are certainly positive signs:

• Spatial planning could allow low impact human activities, which is compatible with high ecosystem retention targets. However, the actual retention target should be state explicitly.
• There is still a focus on protected areas, but the inclusion of OECM linked to a higher representation target (30%) is a move in the right direction.
• The focus on ‘areas particularly important for biodiversity’ shows progress, but there is still vagueness in how these would be defined and measured.
• Fortunately, there are no rate-based targets associated with ecosystems. (However, such targets sneak into the global framework for pollution and alien invasive targets, for example.)

While the proposed ecosystem targets seem to be an improvement on their predecessors, they still need refinement over the next four months. Hopefully, the collective brains of the biodiversity community will find a way to set targets that ensure that the world’s ecosystems are in a better state in 2030 than they are today.