Genetic and phylogenetic diversity in the draft post-2020 global
biodiversity framework
We screened the zero, 0.5, and first drafts of the post-2020 GBF to
examine whether GD and PD are mentioned in Goals, Milestones or Targets
(see Box 1 for explanation of these terms and the hierarchical nature of
the GBF). Focusing on the first draft (
CBD/WG2020/3/3),
although PD was not mentioned once, we found five instances of GD:
- twice under the 2050 Goal A (“The integrity of all ecosystems is
enhanced, with an increase of at least 15 per cent in the area,
connectivity and integrity of natural ecosystems, supporting healthy
and resilient populations of all species, the rate of extinctions has
been reduced at least tenfold, and the risk of species extinctions
across all taxonomic and functional groups, is halved, and genetic diversity of wild and domesticated species is
safeguarded, with at least 90 per cent of genetic diversity within all species maintained”);
- twice under the 2030 Milestone A.3 (“Genetic diversity of wild
and domesticated species is safeguarded, with an increase in the
proportion of species that have at least 90 per cent of their genetic diversity maintained”); and,
- once under the 2030 Action Target 4 (“Ensure active management
actions to enable the recovery and conservation of species and the genetic diversity of wild and domesticated species, including
through ex situ conservation, and effectively manage human-wildlife
interactions to avoid or reduce human-wildlife conflict”).
We screened two further documents to investigate whether any GD or PD
indicators were included in the post-2020 GBF draft monitoring
framework: (i) the proposed monitoring approach and headline, component
and complementary indicators from the third Open-Ended Working Group
(OEWG-3) (
CBD/WG2020/3/INF/2)
and (ii) the latest report from an expert workshop on the proposed
indicators held in Bonn, Germany (
CBD/ID/OM/2022/1/2).
Specifically, we examined whether the indicators proposed by Hoban et
al. (2020) and the Coalition for Conservation Genetics (Kershaw et al.,
2022) for GD and those proposed by the
IUCN Species Survival
Commission’s Phylogenetic Diversity Task Force (PDTF) for PD were included in the draft monitoring framework. We found
that among the three indicators proposed for GD - namely (i) the number
of populations within species with effective population size (Ne) above
500 versus those with Ne below 500, (ii) the proportion of distinct
populations maintained within species and (iii) the number of species
and populations in which genetic diversity is being monitored using DNA
based methods - the first two indicators are included in the proposed
monitoring approach and headline, component and complementary indicators
of the post-2020 GBF (Table 1). The first indicator
is included as a headline indicator to inform Goal A (and previously
recognised Milestone A.3), and is a recommended component indicator for
Target 4. The second one is included as a possible component indicator
for Goal A. These first two indicators are also included in the latest
report from an expert workshop on the post-2020 GBF (Table 1). Importantly, the third indicator – which is the only one
assessing GD monitoring using DNA based methods – is not included
(Table 1). This third indicator is relevant to Target 4, because GD
studies often inform active management actions that support species and
genetic conservation and recovery
\citep{Bolam_2022,Hoban_2021a}. These indicators were recently demonstrated to be
feasible for reporting genetic status for thousands of species at a
national scale by Sweden
\citep{Thurfjell_2022} using available
non-genetic data (e.g. population sizes, historic maps) in national
biodiversity agencies. The indicators are currently undergoing further
testing in Japan, South Africa, Mexico, Sweden, Columbia, Belgium,
France, Australia, and USA (Hoban, Mastretta-Yanes, and da Silva,
personal comm.). Beyond the three GD indicators proposed by
\citet{Hoban_2020} and the Coalition for Conservation Genetics, four other GD
indicators are included in the proposed monitoring approach and
headline, component and complementary indicators of the post-2020
GBF and/or in the latest report from an expert
workshop on the post-2020 GBF (Table 1).
Regarding the two PD indicators proposed by the PDTF, namely (i)
expected loss of PD (also used in \citealp{ipbes2019}) and (ii) the changing
status of Evolutionarily Distinct and Globally Endangered species (EDGE
index), they are both included in the proposed monitoring approach and
headline, component and complementary indicators of the post-2020
GBF (Table 1). The expected loss of PD is included as
a complementary indicator to inform 2050 Goal B (“Nature’s
contributions to people have been valued, maintained or enhanced through
conservation and sustainable use supporting the global development
agenda for the benefit of all”), and the EDGE index as a complementary
indicator to inform 2030 Action Target 4 and 2050 Goal A. They are also
included in the latest report from an expert workshop on the post-2020
GBF (Table 1). These two indicators explicitly link
benefits from biodiversity measured by PD under Goal B, with monitoring
the conservation of evolutionarily distinctive species under Goal A. The
two proposed indicators can demonstrably be produced at the global and
national level for multiple taxonomic groups \citep{ipbes2019,Gumbs_2021}, and the PDTF has committed to producing these
indicators on a regular basis to reduce the reporting burden on Parties
\citep{Gumbs_2021}.
Opportunity to strengthen the conservation of species’
evolutionary potential and history Unlike the CBD strategic plan
2011-2020, GD and PD are now
considered in the draft text for the post-2020 GBF. While their
inclusion could be larger (e.g., including the third GD indicator,
adopting the PD indicators as headline indicators), this represents a
significant improvement compared to the CBD strategic plan 2011-2020 and
an unprecedented opportunity to bring species’ evolutionary potential
and history to the core of public biodiversity policies. Moreover, GD
and PD capture non-market values of biodiversity, and mainstreaming
these non-market values is necessary to achieve transformative change
\citep{ipbes2022}. For instance, while GD embodies strong intrinsic values
as it determines the possibility of the species to survive to new
conditions, PD captures a relational value of biodiversity that ensures
intergenerational equity – representing both current and yet-to-be
discovered biodiversity benefits – which is otherwise neglected in Goal
B.
However, this policy opportunity is necessary but not sufficient to
effectively protect species’ evolutionary potential and history. Whether
this would happen depends on (i) the actual inclusion of GD and PD into
the final, adopted post-2020 GBF and (ii) the implementation of its
targets by the 196 Parties to the CBD, including the European Union.
Parties will need to revise and update their national biodiversity
strategy action plans following the adoption of the post-2020 GBF to
include measures to reach its targets. This may require changes in
policies, legislation and incentives as well as improved monitoring to
report on the above-mentioned GD and PD indicators at the national level
– at least those that will be adopted as headline indicators. Some
legislation is already poised for this – for example, the ‘favourable
conservation status’ targeted for species under the
EU Birds and
Habitats Directives is compatible with the first GD indicator on effective population size
while
Canada’s Species At Risk Act protects genetically distinct populations, which is compatible with the
second GD indicator on the proportion of distinct populations maintained
within species. Further policy work will need to be followed closely,
and supported by scientists, in the coming years.