Fig. 4

Geographical distribution of Syacium papillosum parasites on the Yucatan Shelf (YS). a Spatial representation of a GAMLSS, where the number of parasite species of Syacium papillosum was the dependent variable and the fishing zone, fishing effort and nitrates were independent variables. b Spatial representation of the GAMLSS model, where the number of parasites per sampling site was the dependent variable and zooplankton volume, sum of aliphatic hydrocarbons in water, sum of polyaromatic hydrocarbons in sediment, fish length, number of fish per sampling site, 2,3,5-trimethylnaphthalene, anthracene in sediment, ichthyoplankton abundance and acenaphthylene in water were the independent variables. c Suitable habitat (= probability of occurrence) for parasite individuals in S. papillosum along the border of the continental shelf of the YS, based on habitat suitability for raw data of 23 environmental variables (e.g. Cd, Pb, 17 HCs, SO₂, salinity, total carbon and sediment grain size). d Probability of occurrence of parasite individuals in S. papillosum along the border of the continental shelf of the YS, based on habitat suitability for the first four principal components selected from the raw values of the 23 environmental variables in c. Points indicate sites at which parasites occur