Around the world, terrestrial invertebrates are kept for a variety of reasons, ranging from pollination services to crop protection to public display to silk and wax production. However, despite their widespread use, scientific research has paid little attention to their trade, especially when compared to vertebrates.

There are many potential harmful impacts associated with the terrestrial invertebrate trade, such as overharvesting, the introduction of non-native species into new environments, and the spread of parasites and diseases. These impacts could lead to the loss of the essential ecological roles that invertebrates play. At the same time, the trade is poorly monitored, so many species are still neglected or unprotected.

Given the serious implications of the trade, this research tried to answer three main questions:

1. How many scientific studies are available that investigate the terrestrial invertebrate trade?
2. Which terrestrial invertebrate species are traded and for what purposes?
3. What consequences of the terrestrial invertebrate trade are most often documented in the scientific literature?

The authors conducted a search in June 2023 using major scientific databases. A paper was included if it met at least one of three criteria: it focused on the intentional trade of invertebrates, the collection of invertebrates from the wild, or the farming or captive breeding of invertebrates. The final analysis included 96 papers, most of which (85%) were published after 2010.

Species Traded

A total of 4,315 species were represented in the papers analyzed. Of these:

• 3,164 species belonged to the order Lepidoptera (butterflies and moths)
• 592 species belonged to the order Hymenoptera (bees, wasps, and ants)
• 225 species belonged to the order Araneae (spiders)

Types Of Uses

Overall, 17 different uses were recorded in the literature. Terrestrial invertebrates were most commonly kept as pets (34 papers), used for food (15 papers), and kept as preserved specimens (13 papers).

Live invertebrates were used to feed companion animals, in research and education, as biological controls, and for honey collection and pollination services. Dead individuals were used for decorations, as food, and in traditional medicine. Furthermore, there were also small niche markets for beetle wrestling, alcohol production, fishing bait, composting and soil improvement, and silk and venom production.

Trade Pathways

The trade was documented in Europe (28 papers), Asia (20 papers), Africa (13 papers), South America ( 5 papers), Central America (3 papers), North America (2 papers), and Oceania (2 papers). The country most commonly discussed was Japan (9 papers), followed by the U.S. (8 papers), Mexico (7 papers), and South Africa (7 papers).

Invertebrates were traded online through social media, pet store websites, online classifieds, auction platforms, and the dark web. Physical locations were also common and included community markets, pet stores, grocery stores, department stores, roadside vendors, fairs, and people’s homes. Invertebrates were shipped through the mail, couriered, and, in some cases, smuggled.

Positive Impacts Of The Trade

The trade provides income and food for rural communities. In Laos, for example, cricket collection was reported to be more profitable than rice farming or raising cows. Invertebrate farming is seen as a sustainable alternative to wild harvesting, offering rural communities a stable source of income. Finally, interest in keeping these animals as pets is thought to help people learn to appreciate and conserve them in the wild.

Negative Impacts Of The Trade

The trade increases the risk of introducing non-native species to new environments where they can compete with native species and spread new parasites and diseases. For example, when kept as pets, invertebrates may escape from their guardians or be intentionally released outdoors.

Some species are more at risk from the trade than others. Those that are long lived, mature late, are found only in limited locations, or experience high juvenile mortality are particularly vulnerable to overharvesting. In addition, the rarer the species, the greater the demand, which adds to their vulnerability.

Limitations

The papers included in the analysis were mostly written by authors in the Global North, where researchers tend to have access to more resources such as funding and scientific infrastructure, leading to an overrepresentation of studies from certain regions such as Europe. While the authors of this study translated four papers in other languages into English, they acknowledge that including even more languages and international collaboration would likely have captured more papers for analysis.

More broadly, research on the trade is challenged by the fact that we still know so little about so many terrestrial invertebrates, and even finding an expert who can distinguish different species is difficult.

Addressing The Challenges Of The Trade

Beyond calling for more research on traded invertebrates, the authors make several recommendations to improve the trade’s sustainability:

1. Strengthen education: Implement educational campaigns to raise public awareness of conservation issues, and leverage people’s interest in keeping invertebrates as pets into support for conservation.
2. Enhance monitoring: Improve tracking of both traditional and online markets to capture more details about the trade to inform policy decisions and enforcement measures.
3. Promote captive breeding: Captive breeding may reduce reliance on wild harvesting, and improved practices such as screening animals for pathogens before sale can further protect wild populations.
4. Improve global rules: Make national laws consistent with international legislation, and add more invertebrate species to international protection lists.