Assessing the impact of wildlife trade regulations, with a success story for manta rays

Hollie Booth

Humans exploit and trade wildlife across the globe - for food, clothing, decorations, furniture, medicine and status symbols. However, for all too many species, this represents a major threat to their survival. Slow-growing, economically-valuable species, such as tigers, rhinos and large sharks and rays, are highly vulnerable to trade-driven extinction.

Slow-growing high-value species are most vulnerable to trade-driven extinction. Photo credits: Hollie Booth (far left, centre left, centre right), Wikimedia commons (far right))
Slow-growing high-value species are most vulnerable to trade-driven extinction. Photo credits: Hollie Booth (far left, centre left, centre right), Wikimedia commons (far right))

In an attempt to address this, conservationists often advocate for better regulation of wildlife markets. Regulations may include complete prohibitions on take and/or trade for endangered species, or efforts to facilitate sustainable use, such as quotas and permits.

The Convention on International trade in Endangered Species of Wild Fauna and Flora (CITES) is a global agreement that regulates international trade in listed wildlife species. CITES aims to ensure that trade does not threaten the survival of species in the wild, and is a major political driver for better regulation of wildlife trade (and prohibition of trade in endangered species).

However, wildlife trade regulations are implemented in complex situations. It is often unclear to what degree regulations lead to tangible conservation outcomes, in terms of reduced exploitation of wildlife, and population recovery. What is more, poorly formulated regulations can create perverse and unintended consequences for people and wildlife. As such, impact assessments are needed to understand the extent to which wildlife trade regulations are effective for achieving biodiversity conservation goals, and to learn lessons for future policy interventions. This is particularly pertinent at present, with CITES regulations recently strengthened for more than 130 species , on-going debates on trophy hunting policy and evidence of linkages between wildlife markets and viral diseases such as coronavirus, all of which require appropriate regulatory responses that benefit wildlife and people.

In our recent paper, led by the University of Oxford and the Wildlife Conservation Society, we explore key challenges for assessing the impact of wildlife trade regulations, and offer a practical approach to overcome them. We then apply this approach to a case study on manta ray trade in Indonesia, to assess the impact of CITES and associated implementation actions.


The challenge: oversimplification of wildlife trade issues can lead to flawed assumptions.

Understanding the impact of wildlife trade regulations is hindered by data paucity, bias and uncertainty. These issues need to be explicitly addressed in impact assessments. Failure to do so can lead to flawed assumptions, which is particularly problematic in cases where research may inform policy, and thus have wide-reaching implications.


A potential solution: an integrated framework

Our approach combines an integrated framework for collating and analysing disparate data with a simple yet robust process to assess impact. The approach incorporates quantitative and qualitative data, and can be applied to any regulation, taxa or country context. It could therefore be used to understand the impact of CITES for multiple species and geographies, and help countries assess and adapt wildlife regulations.

An integrated framework and a simple process to assess impact
An integrated framework and a simple, robust process to assess impact. Adapted from Booth et al. 2020.


A case study: a success story for manta ray protection

To demonstrate its utility, we apply this approach to the case of manta ray trade in Indonesia. Manta rays are large, slow-growing species, which makes them especially vulnerable to trade-driven extinction. They have been increasingly targeted in recent decades to meet emerging demand for their gills in Chinese medicine markets. Due to growing concern regarding their overexploitation, manta rays were listed on CITES in 2013, alongside several other commercially important elasmobranch species. In 2014 the Indonesian government declared manta rays as fully protected, and have made concerted efforts to enforce this regulation, including the arrest and prosecution of manta ray traders throughout the country.

Our study represents the first assessment of the impact of CITES on manta ray mortality in a source country. The results indicate that although some catch and trade of manta rays continues, concerted efforts by the Indonesian government to 1) legally protect manta rays (in part catalysed by CITES) and 2) enforce these laws, have led to measurable reductions in exploitation and trade of these charismatic species.

Manta ray
Manta rays are fully protected in Indonesia. Photo credit: Hollie Booth

Implications: there is no ‘one-size-fits-all’ for wildlife trade management

Despite this success story, we caution against one-size-fits-all approaches to wildlife trade regulations and elasmobranch conservation. Full protection will not be the appropriate management response for all taxa, countries and places. For many elasmobranchs, particularly species caught incidentally in non-target fisheries, or those that play important roles in livelihoods and food security, a more nuanced approach may be required. What is more, observed impacts on manta ray hunting and trade differed across locations in Indonesia, highlighting the need for locally-appropriate solutions that are nested within broader national and global strategies. Regulations should be based on species’ ecology and life-history traits, as well as the socio-economic contexts in which they are fished and traded. As such, mixed-methods approaches are essential for designing appropriate and effective interventions into wildlife overexploitation.

For more information, contact the lead author, Hollie Booth (website:, email:, or read the full open-access paper here.