Microhabitat Characterization and Bioaccumulation of Trace Elements in an Invasive Population of Procambarus clarkii (Girard, 1852)

The Pantanos de Villa wetland, a protected Ramsar site in Lima, Peru, faces significant pressure from invasive species and urban pollution. This study provides a comprehensive evaluation of microhabitat use and trace-element bioaccumulation in the invasive crayfish Procambarus clarkii (Girard, 1852). We analyzed the physicochemical parameters of the microhabitat and measured the concentrations of macroelements (Na, Mg, P), trace metals (Cu, Zn, Al, Ni, Ti, Pb), and a metalloid (B) in water, sediment, and crayfish tissues (gill, hepatopancreas, and muscle) using ICP-OES. Additionally, we examined the growth pattern of P. clarkii through its length–weight relationships. A total of 171 individuals were recorded: 99 males and 72 females. Males were longer (13–15 cm), while females were heavier (18–21 g). Additionally, a positive correlation was observed in females between the size and weight of the hepatopancreas and abdominal muscle, whereas no significant link was found in males. Sediments had higher levels of the evaluated chemical elements, with Cu (28.26 mg kg⁻¹) and Zn (66.88 mg kg⁻¹) exceeding international quality guidelines, indicating a possible ecotoxicological risk. The significant negative correlation between dissolved oxygen and the abundance of P. clarkii suggests that higher D.O. is associated with less bioturbation and more predators, making the microhabitat less suitable for juveniles. We conclude that P. clarkii serves as an essential bioindicator and potential vector for the relocation of the trace in an urban wetland, highlighting the need for integrated management strategies to reduce the ecological impacts of this invasive species.