Potential of marine litter for range expansion of the invasive mussel Mytella strigata (Hanley, 1843) along the Indian coast

: Marine litter is a key vector of dispersing invasive species in the marine environment. However, our knowledge of the ecological interactions between these species and litter is still incomplete. Here, we investigated the substrate preferences and physical characteristics of marine litter colonized by the invasive mussel Mytella strigata, and explored the role of litter in the population expansion of this species along the Tamil Nadu coast, India. A total of 72 fouled debris were observed along the study areas. The majority of the fouling litter was composed of plastic (87.5 %), followed by rubber (4.2 %), wood (4.2 %), glass (2.8 %) and metal (1.4 %). A total of 2637 individuals of M. strigata were recorded on the marine litter, with recruitment on plastic substrates. Particularly, M. strigata were most common on large marine litter with irregular or cylindrical shapes, rough surfaces and transparent, blue or green colours. Our work provides evidence that marine litter can play a role in the reproduction of this invasive mussel. Consequently, M. strigata benefits from the litter substrates and the habitat complexity created by anthropogenic materials along the Tamil Nadu coast, enhancing its survival and reproduction. This could promote the expansion of the M. strigata population and thus affect the composition and structure of the marine ecosystem.