Bloom or non-bloom in the giant jellyfish Nemopilema nomurai (Scyphozoa: Rhizostomeae): roles of dormant podocysts

Kawahara, Masato; Ohtsu, Kohzoh; Uye, Shin-ichi

doi:10.1093/plankt/fbs074

Cited by 39 publications

(25 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Scientists have speculated that the warming of the oceans is a vital component in the success of these jellyfish blooms (Kawahara et al 2013). The blooms affect artisanal fishers, i.e, fishing, per Johnson (2006), that is "anchored in household and community based social and economic organization."…”

mentioning

confidence: 99%

To Adapt or Not Adapt: Assessing the Adaptive Capacity of Artisanal Fishers in the Trondheimsfjord (Norway) to Jellyfish (Periphylla periphylla) Bloom and Purse Seiners

Tiller¹,

Mork²,

Liu³

et al. 2015

Mar Coast Fish

View full text Add to dashboard Cite

Worldwide increases of jellyfish has occurred during the last several decades. A dense population of a large scyphozoan jellyfish, Periphylla periphylla, has established itself as top predator in the Trondheimsfjord in Norway, impacting traditional fisheries. On this background we discuss the adaptive capacity of artisanal fishers and stakeholder involvement in environmental management. A serendipitous discovery was that fishers report that their capacity to adapt to the presence of jellyfish in fact was sufficient. What they could not adapt to, within the context of jellyfish proliferation, was top–down decisions from the national government allowing purse seiners into the fjord to harvest Sprat Sprattus sprattus and Atlantic Herring Clupea harengus rest quotas and thereby also large bycatches of the local codfishes. This harvest was perceived more detrimental to their fishery than was the jellyfish invasion. Relative to fisheries management's choice of regulatory mechanisms during times of climatic change, we argue that by involving stakeholders intimately, the resulting policy advice will be experienced bottom–up and, thus, more legitimate and serendipitous results of a critical nature are more likely to surface. Received August 21, 2014; accepted March 20, 2015

show abstract

mentioning

confidence: 99%

To Adapt or Not Adapt: Assessing the Adaptive Capacity of Artisanal Fishers in the Trondheimsfjord (Norway) to Jellyfish (Periphylla periphylla) Bloom and Purse Seiners

Tiller¹,

Mork²,

Liu³

et al. 2015

Mar Coast Fish

View full text Add to dashboard Cite

show abstract

“…In the laboratory, polyps kept at temperatures ≥19 °C never strobilated, but those kept at ≤15 °C did; it took at least a month to start strobilation at 11 and 15 °C and 3 months at 9 °C (Kawahara et al 2013 ). These results suggest that seasonal chilling could be a trigger inducing strobilation in wild polyps.…”

Section: Asexual Reproductionmentioning

confidence: 83%

“…Polyps of N. nomurai , like those of other rhizostome species, produce podocysts as a form of asexual reproduction (Calder 1982 ;Ikeda et al 2011b ), initiating a long-lived dormant phase. They were capable of dormancy for as long as 6 years in the laboratory (Kawahara et al 2013 ). 8.9 ).…”

Section: Intermittent Blooms and Their Possible Mechanismsmentioning

confidence: 99%

“…Ikeda et al ( 2011b ) detailed the histology and histochemistry of N. nomurai podocysts, which consist of a dome-shaped chitinous cuticle that encapsulates a mass of cyst cells fi lled with nutrient reserves (Fig. In addition, the excystment of 8-25 % of polyps was induced when they were returned to well-aerated seawater (DO: >5.0 mg O 2 l −1 ) after they had been exposed to hypoxia (DO: 1.0 mg O 2 l −1 ) for 12 days or burial in organic-rich mud (inducing hypoxia) for up to 3 years (Kawahara et al 2013 ). The metabolic activity of podocysts was extremely low as evidenced by scarcity of mitochondria, rough endoplasmic reticulum, and Golgi complexes.…”

Section: Intermittent Blooms and Their Possible Mechanismsmentioning

confidence: 99%

“…8.10 Schematic representation of the possible distinction in podocyst abundance and behavior (e.g., dormancy or excystment) between bloom and non-bloom years of Nemopilema nomurai medusae (From Kawahara et al 2013 ) In late June, they were distributed in an extended area over the northern East China Sea and the central Yellow Sea at relatively high density (average and maximum: 0.71 and 21 medusae 100 m −2 , respectively). However, it has become possible to predict the bloom intensity in June-July of each year, 1-3 months prior to massive occurrences of medusae in Japanese coastal waters, based on on-deck sighting surveys from ferries.…”

Section: Bloom Forecasting Countermeasures and Future Prospectsmentioning

confidence: 99%

See 2 more Smart Citations