Elemental uptake via immersion: a mass-marking technique for the early life-history stages of ­cephalopods

Abstract

Despite the ecological and increasing commercial significance of cephalopods worldwide, little attention has been paid to developing techniques that investigate the movement of early life-history stages. We evaluated the potential of mass-marking giant Australian cuttlefish Sepia apama hatchlings, via immersion of eggs in water enriched in

Evaluation of the 137Ba mass-marking technique and potential effects in the early life history stages of Sepioteuthis lessoniana

“…There are many factors influencing the success rate of mass marking (e.g. spike concentration or developmental stage; Payne et al 2011;Woodcock and Walther 2014). Consistent achievement of 100% mark success is a vital goal for any mass-marking technique (Warren-Myers et al 2018).…”

“…Following the criteria of Payne et al (2011), the critical value of successfully marked squid was set at 5.78, which was the mean ratio of the control group minus 3 s.d. for 138 Ba : 137 Ba.…”

“…To date, only two studies have evaluated the enriched stable isotope mass-marking technique in cephalopod early life stages (Pecl et al 2010;Payne et al 2011). Maternal injection of stable isotopes in cephalopods may not mark offspring because there is difficulty in determining the oocyte maturity stage in cephalopod ovaries (Pecl et al 2010).…”

“…Maternal injection of stable isotopes in cephalopods may not mark offspring because there is difficulty in determining the oocyte maturity stage in cephalopod ovaries (Pecl et al 2010). By contrast, Payne et al (2011) marked Sepia apama hatchlings by immersing their spawning eggs in solutions spiked with different 137 Ba concentrations (0.3 and 1 ppb) and for different durations (2, 5 and 8 days). These authors demonstrated the potential of using stable isotopemarking techniques to assess the population dynamics of cephalopods in the field (Payne et al 2011).…”

“…By contrast, Payne et al (2011) marked Sepia apama hatchlings by immersing their spawning eggs in solutions spiked with different 137 Ba concentrations (0.3 and 1 ppb) and for different durations (2, 5 and 8 days). These authors demonstrated the potential of using stable isotopemarking techniques to assess the population dynamics of cephalopods in the field (Payne et al 2011). However, the efficacy of marking techniques varies among species.…”