The dark web has caught the attention of the conservation community because of the surge in interest in the illegal wildlife trade. Following our initial systematic study of wildlife trade over the dark web (Harrison et al., Conservation Biology, 2016, 30, 900–904), we have continuously monitored it for further evidence.

One year on, the primary form of business is what we term illegal wildlife trade as bycatch. This refers to wildlife products that are being traded illegally over the dark web, but the reason they are being traded in this forum is that they are potentially illegal for other reasons: the fact that they are wildlife or potentially illegal wildlife is incidental. The two primary forms of illegal wildlife trade as bycatch that we have found are cacti traded for their hallucinogenic properties (Harrison et al., op. cit.), and counterfeit high-end products, notably Chanel handbags, that happen to contain reptile skin. Although it is not possible to verify whether the skins are real or fake, given the price, the high-quality fake Chanel certificates, fake packing tissue paper and the fact that on the dark web a seller's reputation is crucial, the evidence suggests that the skins themselves are likely to be genuine.

There are, however, a few other interesting cases of illegal wildlife trade that are worthy of mention. In our monitoring we focused mostly on high-profile products of conservation concern, principally rhino horn and elephant ivory. So far we have found only three cases of rhino horn for sale. The first appears to be a rather unsophisticated sting operation by a South African investigative journalist group or, less likely, a scam.

The second case is the first credible attempt we have found to sell ivory and rhino horn on the dark web. The items were found on AlphaBay, probably the largest and most popular dark web market. The vendor's store consisted entirely, until mid 2016, of prescription drugs, but in August 2016 a pair of tusks were added, reportedly from the 1960s, and four rhino horns. Having evaluated the information associated with these items, in particular their price and the accompanying image used, and the seller's excellent feedback rating, we conclude the items are genuine. The pictures accompanying the items are cropped from images belonging to the U.S. Fish and Wildlife Service. This may raise questions about the items; however, it is possible that the vendor has merely selected an image from the internet; currently, the items remain unsold.

The third case, also on AlphaBay, is of a seller that seems to have started operations more recently, and most of the items have been on display only since late January 2017. This vendor has a relatively high number of illegal wildlife trade-related items for sale; these include a black rhino horn, an elephant tusk, an ivory statue and an ivory case. Again, and despite their relatively large number of illegal wildlife trade-related products on offer, the vendor has no reported sales. We have not been able to locate copies of the images on the clear web or geo-location data.

So far, we conclude that illegal wildlife trade is occurring over the dark web but only in small quantities. Its most common form is as bycatch, in which the products are potentially illegal for other reasons. We believe we have identified three clear instances of non-bycatch illegal wildlife trade, and therefore continued monitoring is warranted. However, it is unclear whether these few products are on the dark web because of their illegality or whether it is because the vendors are already engaged in other illegal activities that are more prevalent on the dark web. Inadequate enforcement over the clear web means there is still little incentive to move significant quantities of wildlife trade onto the dark web. Again, we warn against sting operations by journalists, conservationists and others (Harrison et al., op. cit.), as this could provide incentive for a move onto the dark web, where law enforcement faces much greater challenges.

We thank B.M. Attewell, J.A. Cripps, J. Duah and D. McRobert for assisting in monitoring wildlife trade on the dark web as part of their final year undergraduate project, and Michael t'Sas Rolfe for useful discussions on illegal wildlife trade and the term bycatch.