Feeding ecology of three tonguefishes, genus Cynoglossus (Cynoglossidae) in the Seto Inland Sea, Japan

Abstract

Feeding ecology was compared among the three tonguefishes Cynoglossus abbreviatus, C. joyneri and C. robustus, collected from Seto Inland Sea, Japan, from June 2000 to May 2001. They are benthivores, consuming mainly gammarid amphipods, shrimps, crabs, gastropods, bivalves and ophiuroids. C. abbreviatus consumed greater proportions of ophiuroids whereas C. joyneri and C. robustus ate more amphipods and shrimps. While C. abbreviatus consumed mostly ophiuroids in all size classes, the diets of C. joyneri and C. robustus showed ontogenetic changes in feeding habits; smaller individuals of C. joyneri and C. robustus consumed gammarid amphipods, whereas larger C. joyneri ate shrimps and gastropods, and larger C. robustus fed mainly on gastropods, crabs, bivalves and polychaetes. Cluster analysis based on diet similarities emphasized that the three Cynoglossus species could be categorized on a size-related basis into three feeding groups: smaller C. joyneri and C. rubustus ( B25 cm TL) could be classified as group A, and the larger of them (!25 cm TL) as group B, whereas C. abbreviatus was categorized as group C. This means that some degree of resource partitioning can occur among the three Cynoglossus species. The seasonal changes in the diets were also significant for the three Cynoglossus species.

Age and growth of the robust tonguefishCynoglossus robustusin the Seto Inland Sea, Japan

“…However, the tonguefish community in the Seto Inland Sea has experienced overexploitation and intensive fishing for several decades, which have caused dramatic shifts in community composition (Inaba 1988). Although a number of taxonomical and biological studies on tonguefishes have been published, little information is available about the ecology of the robust tonguefish (Ochiai 1966;Kim & Choi 1994;Aceves et al 1999;Terwilliger & Munroe 1999;Baeck et al 2011). Several studies have examined the age and growth in Cynoglossus species, including C. semilaevis (Meng & Ren 1988), C. macrolepidotus (Kutty 1967), C. arel (Lin 1982;Rajaguru 1992), C. lida (Rajaguru 1992), C. semifasciatus (Seshappa & Bhimachar 1954), C. abbreviates (Zhu & Ma 1992;Baeck & Huh 2004a), and C. joyneri (Baeck & Huh 2004b).…”

Feeding habits of Kammal thryssaThryssa kammalensis(Bleeker, 1849) in the coastal waters of Gadeok-do, Korea

“…In general, the weight of prey items increases with increasing predator body size, while the number of prey items decreases with increasing prey body size, as in studies of Scomberomorus niphonius, Cynoglossus sp., and Dentex tumifrons (Huh et al 2006;Baeck et al 2011b;Kim et al 2012). However, only the number of prey items of T. kammalensis increased with body size, and the dietary overlap was high.…”

Re-evaluation of the taxonomic status of four nominal, western Pacific species of tongue soles (Pleuronectoidei: Cynoglossidae: Cynoglossus), with redescription of C. joyneri Günther, 1878

“…In Japanese waters, C. joyneri occurs in coastal waters of the southern Sea of Japan and in Pacific coastal waters from Honshu to Kyushu. It is a common species reported from many localities, including Wakasa Bay, Suruga Bay, Osaka Bay, Seto Inland Sea, and off Kochi (Günther 1878;Kamohara 1953;Ochiai 1963Ochiai , 1984Minami & Tanaka 1992;Baeck et al 2011;Yamada 2000Yamada , 2002Yamada & Yagishita 2013).…”