Seasonal migration of the snailfishLiparis tanakaeand their habitat overlap with 0-year-old Japanese flounderParalichthys olivaceus

Abstract

The snailfish Liparis tanakae is an annual fish, growing up to >300 mm in total length. This species is known as a predator of 0-year-old Japanese flounder Paralichthys olivaceus. To reveal when and where the predation occurs, monthly collections of both species at various depths were conducted off Fukushima, Japan. The snailfish inhabited shallow areas ≤50 m deep until June. Thereafter, they shifted their main habitat to offshore areas ≥100 m deep from July to September. The snailfish migrated to inshore areas with depths of ≤50 m again around October–December, during which time the habitat overlap between snailfish and 0-year-old Japanese flounder was observed. In that period, >40% of 0-year-old Japanese flounder were vulnerable to the snailfish. Larger snailfish showed stronger piscivory, and some flatfish were found in their stomachs. These results suggest that by not releasing hatchery-reared Japanese flounder until September can forestall predation by the snailfish.

Long-term changes in the spatio-temporal distribution of snailfish Liparis tanakae in the Yellow Sea under fishing and environmental changes

“…Tanaka's snailfish is from among the 350 demersal species belonging to the family Liparidae, and grows rapidly to 40 cm TL attaining a weight of 1 kg at one year old (Tomiyama et al, 2013), with individual specimens reaching 56.3 cm and 1.7 kg.…”

“…Oceanodromanous, this snailfish inhabits muddy bottom regions at depths of 50−90 m. In the Yellow Sea, snailfish mainly congregate in waters near Haizhou Bay during summer; migrate to shallower waters inshore for feeding during autumn; then move to deeper offshore regions in the central and southern Yellow Sea for overwintering (Zhou et al, 2012). Scholars have conducted ecological research focusing on seasonal changes in biological characteristics and resource distribution (Tomiyama et al, 2013;Myoung et al, 2016;Chen et al, 2022), trophic level (Zhang et al, 2007), feeding ecology (Zhang et al, 2011), helminth parasites (Guo et al, 2014) and complete mitochondrial genome (Liu et al, 2022). As one of the top predators in the Yellow Sea ecosystem, the snailfish feeds on more than 60 species and plays an important ecological role in regulating the biomass of other species through a top-down effect (Zhang et al, 2011;Lin et al, 2013).…”