Forest certification is widely seen as an important component of strategies for conserving the world’s forests. During the 1990s concern about the loss of biodiversity in logged forests was a key driver behind the emergence of forest certification. It was thought that production forests could play a bigger part in conserving nature by adhering to a strict and widely agreed forest management standard that considers the effects of logging and other forest management activities on biodiversity. Since the introduction of forest certification more than 300 million hectares of forests have been certified under a variety of schemes, although less than 20 million hectares are in the tropics, mostly certified by the Forest Stewardship Council (FSC).

Although interest in forest certification has waxed and waned, it remains a cornerstone of forest policies. But does it work? As more than 15 years have passed since the first certificate was issued, it should be possible to evaluate the effectiveness of certified forest management by comparing the conservation performance of certified forests with non-certified forests.

A literature study on this subject has revealed the difficulty of providing a clear answer to this question. In the first place, in most certified forests the data needed to assess the effects of management on biodiversity are not being systematically collected. Data from non-certified forests, which are needed for comparison, are even harder to find. The scientific community has not yet risen to the challenge of providing evidence of the effects of certified forest management on a comprehensive scale. Studies focus on different species, use different protocols and do not address the large temporal and spatial scales covered by tropical production forest.

A complex issue
This is regrettable, but it does not come as a surprise, given the complexity underlying the concept of ‘biodiversity’ – even its simplest definition as species richness and abundance. Different species, even related ones, respond in different ways to the same management activity, and require different research protocols. Moreover, the short-term effects of logging may be very different from the long-term effects. Conclusions drawn about the changes in the number of species present in a forest may fail to reveal underlying shifts from forest specialists to habitat generalists.

Similarly, ‘certified forest management’ is a complex topic. Forests differ from place to place, and so management practices vary. Differences in logging intensity, logging pattern and timing, the size and variety of species harvested, extraction methods and post-harvest activities all contribute to different responses by plants and animals.

In the face of these difficulties, the conclusions drawn from the literature can only be tentative. Only a handful of studies, all in a certified forest in Sabah, have directly assessed the effects of certified forest management on a number of plant and animal species. They showed that populations of endangered animals increased. For want of any direct assessments of certified production forests, the literature study concentrated on a number of good forest management practices associated with certification, in particular Reduced Impact Logging, the establishment of streamside buffers, protected areas and corridors, and High Conservation Value Forests.

Biodiversity benefits
In general, the studies reviewed suggest that forest certification has positive biodiversity benefits. This is in agreement with information gathered from discussions with certifiers and forest managers with experiences in the field. Despite the apparent differences in the rigour with which biodiversity concerns are addressed under different certification systems, the planning, supervision and basic good management practices required by all of them serve to mitigate many of the harmful environmental impacts of logging and other forest management activities. Similarly, these studies confirm that despite their better performance, certified forests are not fully equivalent to undisturbed or primary forests in terms of biodiversity.

Recommendations
The review also shows that the impacts of certified forest management on biodiversity cannot be assessed without a clear idea of the relative importance of species and the management objectives. This leads to several recommendations.

• As different species may be valued differently by different stakeholders – based on considerations of rarity, vulnerability, endemicity, distinctness, economic usefulness, potential as a pest, religious and spiritual value, and many other considerations – formulating appropriate functions of production forests in conserving biodiversity requires debate and negotiation at the local level (but without dismissing global interests).
• The results of these discussions must be translated into practical management activities for achieving specific, measurable biodiversity objectives. These must be subject to periodic revision to accommodate changes in value perception and in the state of biodiversity in the forest.
• To further inform the trade-offs between biodiversity and the social and economic interests of forest management accepted by certifiers, scientists will have to provide quantitative, field-based evidence of species responses to forest management practices, and to propose modifications if that is required.
• Finally, biodiversity monitoring and audits of certified forest management should focus on these management objectives rather than on general, unspecified biodiversity goals. Such goals are almost impossible to measure and, if they can be measured, hard to interpret.

The challenge for forest managers, certifiers and biodiversity researchers is to promote forest certification from a credible proposition to a demonstrated asset in the suite of instruments available for forest biodiversity conservation.

Related publication: Effects of Forest Certification on Biodiversity