Global wildlife trade affects the Tree of Life—including orchids
Although we know that wildlife trade poses a major threat to biodiversity around the world, global trading patterns remain poorly understood. Notably, what groups of plants and animals are most affected by illegal trade?
Until recently, no comprehensive analyses of the global wildlife trade had been made, except studies on terrestrial vertebrates. To address this gap, researchers undertook a global study of how trade affects the full diversity of organisms represented in the IUCN Red List database that track species’ conservation status.
"To us, it is evident that the phenomenon of the global wildlife trade is much more complex and widespread than previously acknowledged," says Stefano Mammola, researcher at the Italian National Research Council and co-author. "Even though the wildlife trade permeates all branches of the tree of life - from fungi to plants, from small marine species to big terrestrial mammals - more attention is given to the trade of a small selection of charismatic species, preventing the development of comprehensive and effective conservation strategies."
There is growing concern about this systematic bias on a certain species, notably large vertebrates over other animals and plants. It is a common among the general public, scientists and policy makers, and is also responsible for the phenomenon called ‘plant blindness’—the human tendency to ignore plants. While vertebrates only account for approximately 1% of existing species, this small group is often used to make decisions that affect the whole range of life on Earth.
Cattleya trinae, an endangered orchid threatened by trade.
"We are facing a biodiversity crisis. We need to be fast and effective in filling our gaps in knowledge, especially about non-vertebrate species. In this way, we can achieve a deep understanding of global trading patterns across the full canopy of the tree of life, and not just its most appealing twig," says Pedro Cardoso, co-author based at the Finnish Museum of Natural History.
The researchers did this by evaluating how trade affects species on the IUCN Red List, the database that provides the most comprehensive information on the global conservation status of animal, fungi, and plant species. However, the researchers recognise that the bias towards large animals is also present in the IUCN Red List, making it difficult to make inferences about all species on Earth. For example, of the approximately 27,000 orchid species in the world, only about 1,641 (about 6%) have had their conservation status evaluated by the IUCN.
Nevertheless, based on the existing data, the researchers have taken the first step in analysing how global wildlife trade affects different groups. Looking only at absolute species numbers, the most traded group of organisms are vertebrates. However, because of the vertebrate bias of IUCN assessments, looking at absolute species numbers can be misleading. The researchers then looked at the ratio of traded versus non-traded species in each group.
This is where it became abundantly clear that the wildlife trade affects a huge range of species across the tree of life including plants, fungi, major invertebrate groups and terrestrial and aquatic vertebrates.
For example, approximately 15% of all threatened plants are traded and more than 70% of critically endangered, endangered, and vulnerable species in the Phyla Echinodermata (sea stars, cucumbers, urchins) and Cnidaria (corals, anemones, jellyfish) are threatened by the trade. By comparison, trade is a leading threat to 30% of threatened vertebrate species.
Orchid trade was also highlighted within the paper. Although not receiving the same level of attention as many charismatic vertebrate species, they make up approximately 70% of species listed on CITES Convention that governs international wildlife trade. They are among the most commonly traded species internationally with the researchers finding that between 2000-2005, 370 million orchids were traded internationally -- during the same period 1.7 million snakes, 5.7 million lizards, 600,000 turtles and 236,000 amphibians were traded. Alarmingly, orchids also represent a large group threatened by trade, particularly for their value in the collector market.
The researchers highlighted the important distinction between species that are being traded, and species that are threatened with extinction due to the trade. For example, many orchid species are being traded globally, but we do not know the conservation status for most of these. A notable exception are the lady slipper orchids, all but one of which the IUCN states as threatened by wildlife trade.
A wild Phragmipedilum orchid (Lady slipper orchid)
Source: Andreas Kay
While the IUCN Red List and CITES Trade Database contain significant information on the global conservation and trade of species, careful interpretation is needed to avoid misperceptions about the current state of the global wildlife trade. These researchers have taken the first step in producing an extensive analysis of the global trade, accounting for a fuller diversity than previous studies. They highlight that wildlife trade is much more complex than previously acknowledged and orchids as one of the groups threatened by the trade. However, they emphasise that more unbiased, broader representation of species, including plants, fungi and invertebrates, is critical to truly understanding how trade affects all areas of life.