Contributions to Zoology, 86 (1) – 2017Vincent Nijman; Daniel Bergin: Reptiles traded in markets for medicinal purposes in contemporary Morocco
Material and methods

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Analysis

Several species that are sold for medicinal purposes are also traded for other uses (e.g., to be used as pets) and it was not always possible to establish their intended purpose with certainty. In the few cases were there could have been uncertainty about usages, or when animals were offered for sale for potentially multiple purposes, we made an educated guess using contextual data to include or excluded these observations to eliminate questionable data. Thus, a live chameleon for sale in a shop selling live tortoises is most likely to be sold as a pet, but a live chameleon for sale at the store of an herbalist is more likely to be used for medicinal purposes. Likewise, tortoise carapaces on display at a medicinal shop suggest use in medicine, whereas the same carapace on display in a tourist shop is likely to be sold for decorative purposes. In the market, we requested the asking prices for the most commonly traded species and converted these to US dollars (US$) using an exchange rate of nine Dirham (MAD) to the dollar. We used these prices to calculate the value of each species in trade, and summed them to arrive at an overall value of the trade. Asking prices will go down after bartering or when more than one specimen at a time is purchased. Because we did not want to make any purchases, the overall figure we present in our results may overestimate the total value of the trade.

For each species in each market, we calculated the average number of species that we observed per survey (i.e., dividing the total number of individuals observed in a particular town by the number of surveys that were conducted in that town). We used four cities that were surveyed multiple times (i.e., Casablanca, Fez, Marrakesh, and Meknes), which we believe are representative of different aspects of the trade in reptiles in Morocco, to compare markets in more detail. For each market city and for each survey, we calculated the total number of species for sale as a measure of species richness, as well as the proportion of trade in live animals versus dried animals; differences between market cities were tested using ANOVAs.

We calculated minimum turnover of Mediterranean chameleon and Bell’s Dabb lizard two commonly observed species, by repeat visits to eight individual shops for the chameleons (four shops in Marrakesh, two shops in Fez and Rabat) and six individual shops for Bell’s Dabb lizard (four shops in Meknes, two shops in Marrakesh), all within a four-week period. It was not possible to calculate turnover when in between surveys a new consignment of animals had arrived and the number of Mediterranean chameleons or Bell’s Dabb lizards in the shops had increased; our turnover figures thus are minimum estimates. Using the four-week turnover figures, we calculated annual numbers of turnover for each city in which we observed Mediterranean chameleons or Bell’s Dabb lizards for sale and combined them for an overall annual figure. For the other species, we were not able to collect firm data on turnover but, given the non-perishable nature of many items, we expect that at least parts of the inventory can remain unsold for several months. To reduce the effect of non-independence of data in exploring temporal patterns, we used data from surveys done at least three months apart.

For testing whether observed frequencies of occurrence were homogeneously distributed over all classes, and whether significant differences existed between the different classes, we used sequential chi-square tests. Expected frequencies were generated based on a random distribution proportional to sampling effort per market or per survey. Pearson product-moment correlation coefficients were calculated to explore correlates with trade volumes. Statistics were run in R (R Development Core Team, 2015); we present means and ranges and accepted significance when P < 0.05.