Biomass, body elemental composition, and carbon requirement of <i>Nemopilema nomurai</i> (Scyphozoa: Rhizostomeae) in the southwestern Japan Sea

Abstract

Biomass and body elemental composition of the giant jellyfish Nemopilema nomurai in the southwestern Japan Sea were studied using specimens collected with mid-water trawl nets during September and October 2006, 2007. The average biomass of N. nomurai was calculated as 0.26-0.93 g wet weight (WW) m . Body elemental composition of N. nomurai was water=95.8% of WW, carbon=6.6% of dry weight (DW), nitrogen=1.7% of DW, and phosphorus=0.14% of DW. Carbon requirements for growth and respiration were estimated in per unit area using biomass data. For growth analysis, size-frequency distributions of bell diameter (BD) were examined from specimens collected using set-nets in Wakasa Bay during August-January in 2005-2007 and the growth rate was calculated as 1.5 cm d . Biomass and carbon requirement data of N. nomurai were compared to the biomass of the common squid Todarodes pacificus and copepod production, respectively, in the Japan Sea. In the present study, it was demonstrated that when mass incidences of N. nomurai occurred in the Japan Sea, the biomass of N. nomurai was substantial and equivalent to that of the common squid. The amount of zooplankton consumed as prey by N. nomurai was not large enough to influence the biomass of zooplankton as a whole; however, it was critical for dense aggregations in a small area.

Wind Drifting vs. Pulsating Swimming Jellyfish: Respiratory Metabolism and Composition Differences in Physalis physalis, Velella velella, Aurelia aurita, and Pelagia noctiluca

“…Comparing our WM-specific R results with similar studies in the literature (Table 1), we observe that, with regards to A. aurita, the average R/WM presented in this article (Table 1) was below some of the recently published results (Møller and Riisgård, 2007;Shimauchi and Uye, 2007) and above some others (Uye and Shimauchi, 2005;Han et al, 2012;Iguchi et al, 2017). Iguchi et al (2017) reported ETS activities in 10 A. aurita medusae (Table 6). They used this information to estimate R in the giant jellyfish Nemopilema nomurai, observing great potential in the application of the ETS assay.…”

“…The results in this work for the 6 A. aurita medusae were closest in size to A. aurita in their study (Table 6), showing a considerable difference. The difference between studies may Iguchi et al (2017) and from our study. Iguchi et al (2017) This study N 10 6…”

“…Jellyfish have been described as the main competitor of zooplanktivorous fish (Pauly et al, 2009), thereby known as predators as well as competitors of several commercial fish species. Substantial efforts have been made to quantify and assess the impact of this consumption (Larson, 1987;Morand et al, 1987;Schneider, 1989;Purcell, 1997;Uye and Shimauchi, 2005;Ishii and Tanaka, 2006;Han et al, 2012;Iguchi et al, 2017;Nagata and Morandini, 2018). Furthermore, several studies have investigated the formation of dense aggregations by some jellyfish and their impact on prey populations (Malej, 1989a;Mills, 1995;Schneider and Behrends, 1998;Hansson et al, 2005;Ishii and Tanaka, 2006;Condon et al, 2011;Boero, 2013;Iguchi et al, 2017;Schiariti et al, 2018).…”

“…Substantial efforts have been made to quantify and assess the impact of this consumption (Larson, 1987;Morand et al, 1987;Schneider, 1989;Purcell, 1997;Uye and Shimauchi, 2005;Ishii and Tanaka, 2006;Han et al, 2012;Iguchi et al, 2017;Nagata and Morandini, 2018). Furthermore, several studies have investigated the formation of dense aggregations by some jellyfish and their impact on prey populations (Malej, 1989a;Mills, 1995;Schneider and Behrends, 1998;Hansson et al, 2005;Ishii and Tanaka, 2006;Condon et al, 2011;Boero, 2013;Iguchi et al, 2017;Schiariti et al, 2018). Quantifying consumption rates of these organisms will aid in the assessment of their effect on the recovery of populations in areas where jellyfish are proliferating (Purcell et al, 2007;Richardson et al, 2009;Boero, 2013).…”

“…Quantifying consumption rates of these organisms will aid in the assessment of their effect on the recovery of populations in areas where jellyfish are proliferating (Purcell et al, 2007;Richardson et al, 2009;Boero, 2013). Carbon demand, associated with the respiratory activity can be calculated from the respiration measurements, which can help in the estimation of the impact on prey populations (Purcell et al, 2010;Lilley et al, 2014;Iguchi et al, 2017).…”