Atlantic seabob shrimp as biomonitor of Cu and Zn near port activities: is it really a suitable choice?

Abstract

The trace elements concentration in the muscle of the Atlantic seabob shrimp (Xiphopenaeus kroyeri) caught in coastal fishing highlighted copper (Cu) and zinc (Zn), both related to antifouling systems, as the main elements related to the intensity of port activities of southeast Brazil (~20—to 22ºS). The aim of this study is to analyze if the behavior of Cu and Zn in the muscle of this shrimp species is constant among different sampling sites, verifying if the species is suitable as biomonitor for these elements. The shrimps came from fisheries done in 2017 in Vitória, Anchieta, and Farol de São Tomé, southeast Brazil. After sampling, each individual was categorized for gender and maturity stage, measured, and weighted. Bulk muscle samples were freeze-dried for determination of Cu, Zn, and ratios of stable isotopes of carbon (δ13C) and nitrogen (δ15N). The data analysis verified if the concentration of Cu and Zn in male and female shrimps vary among maturity stages and sampling sites, and how the concentration of Cu and Zn is related to shrimps foraging area and/or trophic position. Both bioaccumulation and growth dilution occurred, but not in the same way for genders and sampling sites, with Cu showing more variability. Relationships between elements and shrimps foraging area and trophic position did not show a clear trend among the sampling sites. Regression models indicated moderate relationships, explaining 51% (Cu) and 60% (Zn) of the association with the foraging area in Anchieta, but up to 8% in Vitória and Farol de São Thomé. For the trophic position, the models explained 33% (Cu) and 34% (Zn) in Anchieta and up to 14% in Vitória and Farol de São Thomé. The results showed that the utilization of this shrimp species as biomonitor of marine coastal environments near port activities to monitoring the levels of Cu and Zn is not a suitable choice, at least in the spatial scale considered by this study.