Protected areas and Community Forest Management (CFM) are among the most widespread
interventions to conserve forests in tropical countries. In addition to their impacts on forests and the
biodiversity they contain, these interventions also affect human well-being, particularly that of the local
communities who are often poor and politically marginalized and whose livelihoods depend directly on
the forest resources being conserved. To develop effective interventions, practitioners need to have
credible, strong and scientifically rigorous evidence on their impacts on forests (or the biodiversity they
contain) and human well-being. However, while scientifically rigorous impact evaluation of programs
is well advanced in fields such as development, health and education, it is rare in nature conservation.
The rare existing studies focus mostly on protected areas and other interventions, such as CFM, are
relatively untouched by scientifically rigorous impact evaluation.
Different challenges account for the limited adoption of rigorous impact evaluation in nature
conservation. Among these are the identification and elimination of rival explanations: factors other
than the intervention that can explain the observed relationship between the intervention and the
outcome. Potential rival explanations are factors that can confound impact estimates by affecting both
assignment of units to intervention and the outcome. Another potential rival explanation is baseline
outcome data that should have been collected before the intervention was implemented. Baseline data
are often missing in conservation studies. Another challenge is the heterogeneity of management
practices within and units exposed to the same intervention. A challenge pertaining particularly to
studies on human well-being impacts is the multi-dimensional nature of human well-being.
In this thesis, I aim to investigate the impacts of different conservation interventions on environmental
and human well-being outcomes while addressing the challenges to conservation impact evaluation
discussed above. My case studies are CFM and strict protection in Madagascar; one of the world’s
hottest biodiversity hotspots. I have three specific objectives which are addressed in three manuscripts
with the following titles:
i) Effectiveness of CFM at reducing deforestation across Madagascar (manuscript 1): With
colleagues, I investigated the impacts of CFM on deforestation at the national scale between 2000
and 2010 using matching to control for factors confounding impact estimates. We did not detect an
impact of CFM, on average, when CFM areas were compared to non-CFM areas, even when the
sample was restricted to only where information suggests effective CFM implementation on the
ground. However, impacts were heterogeneous conditional on whether CFM permits commercial
use of forest resources. No CFM impact was detected where commercial use of natural resources is
allowed. However, we did detect some reduction of deforestation in areas managed under CFM that
does not permit commercial use, when compared to non-CFM or CFM permitting commercial use.
Our findings suggest differentiating among types of CFM is important for estimating the impacts of
this conservation approach.
ii) Impacts of CFM on human economic well-being across Madagascar (manuscript 2): In this
manuscript, we investigated impacts on household living standards across Madagascar as measured
by per capita consumption expenditure. We used matching to control for confounding factors and
addressed the issue of missing baseline values of household consumption expenditures using an
approach known as the placebo test. We cannot statistically reject the hypothesis of zero impact,
but we can credibly reject the hypothesis that CFM has had substantial negative impacts on
economic well-being across CFM communities in Madagascar. There were heterogeneous impacts,
with a mixture of positive and negative impacts, conditional on household proximity to forest and
education level. In conclusion, the impacts of CFM vary with household characteristics: some may
lose while others may gain.
iii) The potential of the Global Person Generated Index (GPGI) for evaluating the perceived impact of
conservation interventions on subjective well-being (manuscript 3): In this study, we used the
GPGI, a subjective and multidimensional well-being instrument, to investigate the relative impacts
of strict protection and CFM on human well-being in sites in eastern Madagascar. We used a
participatory approach to establish the cause-effect relationship between the interventions and the
outcomes (i.e., to eliminate rival explanations). We did not detect statistically significant difference,
on average, between the two approaches in three measures we used to examine the magnitude of
their relative impacts on subjective well-being. However, we found some differences in the
characteristics of subjective well-being component domains impacted by the strict protection and
CFM and in the priority domains that could be targeted by increased resource allocation to improve
well-being in locally meaningful ways. Combined with the participatory approach to establish
cause-effect relationship, we suggest GPGI provides highly relevant insight that can be used to
design policy seeking to increase local participation and develop more positive local attitudes
towards conservation.
The first two manuscripts (1 and 2) involve analyses at the national scale, objective indicators
(deforestation and consumption expenditure) and rigorous quantitative causal inference designs making
them of value to external stakeholders, such as government agencies and donors, seeking to know the
magnitude of impacts to inform large scale conservation policy. However, these large scale studies may
be of limited use for project managers who want to build locally legitimate interventions or those who
want a deeper understanding of how conservation interventions affect local people. In the third
manuscript, we used a subjective measure of well-being (the GPGI) in combination with participatory
approach to establish cause-effect relationship between interventions and locally meaningful outcomes.
This has limited value for quantitatively measuring the magnitude of impacts; but holds some promises
for project managers who seek local participation and social sustainability. Conservation has long
suffered from poor quality evaluation of its impacts. This thesis shows that methods for impact
evaluation are available, but the appropriate method that should be applied depends, among other
things, on the purpose of the evaluation.