Trade of legal and illegal marine wildlife products in markets: integrating shopping list and survival analysis approaches

Wildlife is an important source of nutrition and income for rural communities. The International wildlife trade of endangered species is regulated by CITES, but domestic wildlife markets are rarely subjected to this degree of scrutiny. Market surveys provide important domestic trade data but suffer limitations. Occupancy modelling, using search effort, can be applied to market surveys. To compare the availability of marine consumables from species threatened with extinction, we undertook market surveys using a ‘shopping list’ of threatened species. Items included turtle eggs and shark products. Turtle eggs from the Ostional Egg Project are sold under a certification scheme, but non-certified eggs are readily available. The surveyors were local residents employed to complete the market survey. The search effort for each item was compared using an adaptation of survival analysis. Time to find each item indicated availability. We tested whether demographics and shopping habits affected surveyors’ ability to and the items. Shark products were found fastest and were, therefore, the most readily available item. Non-certified eggs were found as easily as Ostional certified eggs, implying there are few deterrents to the open sale of non-certified eggs. The shopping habits of surveyors had no effect on their ability to find eggs. Integrating the shopping list with survival analysis can reveal valuable information on demand and supply, which would otherwise be difficult to obtain using traditional surveys.