Bottom trawling disturbs vast areas of seafloor habitat annually, killing enormous numbers of non-target species and damaging the ecosystems that support marine life.
Bottom trawling causes welfare harms at enormous scale. Non-target species — including fish, invertebrates, marine mammals, and seabirds captured in bycatch — are killed or injured in vast quantities. The welfare of these individual animals — the stress, injury, and death involved in capture and discard — is an urgent issue alongside the ecological consequences of habitat destruction. Trawled animals experience acute capture stress, physical injury from gear contact, decompression injury from rapid depth change, and discard mortality when returned to the water. The destruction of complex benthic habitat simultaneously destroys the ecological foundation that supports the welfare of entire marine communities over much longer timescales. Selective gear, area closures, and ultimately transitions to more sustainable fishing methods are the welfare and conservation response.