Feeding ecology of larvae of southern bluefin, albacore and skipjack tunas (Pisces: Scombridae) in the eastern Indian Ocean

Abstract

Copepod naupl~i, calanolds, cyclopolds and cladocerans (all Crustacea) were the maln prey of the larvae of southern bluefin Thunnus macco)w and albacore tuna T alalunga In the eastern Indlan Ocean, although the importance of each prey type differed between the 2 specles Cannibalism was found in post-flexion T m a c c o p Sklplack tuna K a t s u~v o n u s p e l a m~s larvae fed malnly on appendlcularlans and flsh larvae T maccoyij selected for copepod nauplli and corycaeids and a g a~n s t calanoids T alalunga selected for corycaelds and agalnst calano~ds K pelamjs selected for appendlcular~ans The 2 Thunnusspecies fed only by day, wlth peaks in feedlng In the early mornlng and late afternoon The gut evacuation tlme of T alalunga was e s l n~a t e d at ca 4 h Indexes of feedlng success ~n T maccoy11 were posihvely correlated with zooplankton bion~ass, whlch suggests food was lim~ted Estimates of the dally ratlon and abundance of larval tuna and the abundance of rnlcrozooplankton In the study area ~n d~c a t e that l a~v a l T m a c c o p can affect the abundance of thelr mlcrozooplankton prey

Intra- and interspecific variability in prey size and niche breadth of myctophiform fish larvae

“…Last 1980, Hunter 1981, Young & Davis 1990, in the fishlarvae species we studied the size of ingested prey increased throughout development. This pattern is obviously related to increases in speed, perceptive distance and capture efficiency with increasing larval size (Hunter 1981).…”

Tuna Nutrition and Feeds: Current Status and Future Perspectives

“…However, the food spectrum for tuna changes during ontogeny with larvae feeding primarily on small zooplankton, mainly copepods and copepoda nauplii (Uotani et al, 1990). Specifically, PBT larvae in the northern Pacific were shown to feed on zooplankton, including copepod nauplii, calanoids, cyclopods, cladocerans and corycaeids (Uotani et al, 1981(Uotani et al, , 1990Young and Davis, 1990), whereas juveniles and adults are opportunistic feeders. Thus, juvenile PBT feed on crustaceans, fish and cephalopods, while adults feed predominantly on fish (herring 6 Clupea harengus, sand lance Ammodytes spp,, bluefish Pomatomus saltatrix, mackerel Scomber scombrus and various anchovy, sardine and sprat species).…”

“…At a very early developmental stage, tuna larvae acquire predatory piscivorous habits and consume daily rations between 25 and 50% of total body mass (Young and Davis, 1990;Tanabe, 2001). Cannibalism is usually found in the larvae and juveniles of tuna in nature, mainly in reproductive areas (Tanabe, 2001).…”

“…Like many other pelagic marine fish, the early life stages of tuna are visual predators feeding during daylight hours (Uotani et al, 1990;Young and Davis, 1990), with larvae consuming primarily small zooplankton, mainly copepods and copepoda nauplii (Uotani et al, 1990). At a very early developmental stage, tuna larvae acquire predatory piscivorous habits and consume daily rations between 25 and 50% of total body mass (Young and Davis, 1990;Tanabe, 2001).…”

Small-scale patterns in distribution and feeding of Atlantic mackerel ( Scomber scombrus L.) larvae in the Celtic Sea with special regard to intra-cohort cannibalism

“…Piscivory and its special form, cannibalism, is an uncommon foraging mode for marine fish larvae and is primarily found among members of the scombridae (Lipskaya 1982;Jenkins et al 1984;Shojii et al 1997;Young and Davis 1990;Sakakura and Tsukamoto 1996) and larvae of freshwater species (for review see Hecht and Pienaar 1993). Folkvord (1997) ascribed the higher occurrence of larval (coeval) cannibalism in freshwater species, to the fact that those are generally more developed at hatching than marine larvae.…”