Age and growth of lanternfishes, Symbolophorus californiensis and Ceratoscopelus warmingii (Myctophidae), in the Kuroshio–Oyashio Transition Zone

Abstract

To estimate the age and growth of dominant lanternfishes in the Kuroshio-Oyashio Transition Zone, we examined the sagittal otolith microstructure of Symbolophorus californiensis (n = 30) and Ceratoscopelus warmingii (n = 93) collected from the western North Pacific during 1997-2003. Age of S. californiensis ranged from 81 to 541 days corresponding to postmetamorphosis stage (juveniles and adults), and the von Bertalanffy model was fitted: L t = 128[1 − exp{−0.003(t − 1.52)}], where L is the standard length (mm) and t is age in days. Age of C. warmingii ranged from 6 to 416 days, and growth before metamorphosis was linear (L t = 0.346t + 1.51), and the von Bertalanffy model was fitted to the postmetamorphosis stage: L t = 80.8 [1 − exp{−0.00769(t − 34.4)}]. Growth of these two lanternfishes was faster than that of other lanternfishes in previous studies but considerably slower than that of Japanese sardine (Sardinops melanostictus) and anchovy (Engraulis japonicus) distributed in the KuroshioOyashio Transition Zone. Temperature and prey availability are discussed in relation to this difference in growth rate.

Larval stage duration, age and growth of blue lanternfish Tarletonbeania crenularis (Jordan and Gilbert, 1880) derived from otolith microstructure

“…However, the observed abrupt shift between otolith growth and somatic growth in larval and postlarval T. crenularis indirectly supports such an interpretation. A similar disruption was reported in several myctophid species, e.g., Benthosema glaciale and Loweina rara (Linkowski 1991), and Ceratoscopelus warmingii (Takagi et al 2006). The vast difference of otolith size between the largest larvae and the smallest postlarval fish examined also supports our interpretation of somatic growth suppression during non-migratory behavior of transforming larvae and early juvenile T. crenularis.…”

“…Other published results indicate lower (minmax) number of increments in the middle zone of several myctophid species, e.g. 13-43 for Benthosema suborbitale (Gartner 1991b), 69-89, 24-54, and 20-65 for Ceratoscopelus warmingii (Tsarin 1994;Linkowski 1997;Takagi et al 2006, respectively), 10-12 for Diaphus kapalae (Suthers 1996), 38-60 for Electrona antarctica (Greely et al 1999), 5-9 for Lampanyctodes hectoris (Young et al 1988), 15-40 for Lepidophanes guentheri (Gartner 1991b), 20-35 for Myctophum nitidulum (Giragosov and Ovcharov 1992), and 23-61 for Symbolophorus californiensis (Takagi et al 2006). In contrast to the published data for other myctophids, except for C. warmingii (Tsarin 1994), we observed the middle zone of the T. crenularis otoliths had more numerous increments.…”

“…It is widely accepted that variables such as photoperiod, temperature, feeding, growth, and circadian rhythm have a potential to influence otolith deposition (see review by Campana and Neilson 1985). Additionally, mesopelagic fish exhibit vertical distribution patterns, such as diel or lunar migrations and periods of nonmigratory behavior in some developmental stages (e.g., Clarke 1973;Badcock and Merrett 1976;Karnella 1987;Linkowski 1996;Hayashi et al 2001;Shelekhov 2004;Takagi et al 2006;Sassa et al 2007) that may further influence otolith microstructure (Gjøsaeter 1987;Gartner 1991a;Linkowski 1991Linkowski , 1996Linkowski , 1997Takagi et al 2006). This makes the myctophid otolith a particularly useful tool to decipher duration and chronology of some life history events.…”

“…Published results indicate relatively low (minmax) number of increments in the central zone, e.g. 30-50 for Benthosema suborbitale (Gartner 1991b), 22-52 for Ceratoscopelus warmingii (Linkowski 1997), 31-48 for Diaphus kapalae (Suthers 1996), 33-43 for Myctophum nitidulum (Giragosov and Ovcharov 1992), and 30-64 for Symbolophorus californiensis (Takagi et al 2006). In contrast with published data for other myctophids, T. crenularis has two to five times more increments within this part of otolith.…”

“…The central part in sectioned myctophid otoliths is most often described as the "larval zone" and is formed during the occurrence of larvae in highly dynamic epipelagic layers (Ozawa and Peñaflor 1990;Gartner 1991a, b;Greely et al 1999) where they perform restricted diel vertical migrations (Badcock and Merrett 1976;Loeb 1979a, b;Karnella 1987;Sassa et al 2007). The published nomenclature of the "middle zone" in myctophid otoliths (Gjøsaeter 1987;Young et al 1988;Ozawa and Peñaflor 1990;Gartner 1991a, b;Giragosov and Ovcharov 1992;Linkowski et al 1993;Suthers 1996;Linkowski 1997;Greely et al 1999;Hayashi et al 2001;Moku et al 2001;Shelekhov 2004;Takagi et al 2006) is more complex and often controversial due to different interpretations of the relation between otolith formation and migratory behavior and/or ontogenesis. The external part of otolith microstructure is enhanced by circadian rhythm and cyclic diel environment changes, particularly the temperature gradient traversed by stages that exhibit vertical migration (Gibson 1978;Torres et al 1979;Campana and Neilson 1985), which is the case in myctophids (Gartner 1991a;Hayashi et al 2001).…”