Distribution of ephyrae and polyps of jellyfish Aurelia aurita (Linnaeus 1758) sensu lato in Mikawa Bay, Japan

Natural predators of polyps of Aurelia aurita s.l. (Cnidaria: Scyphozoa: Semaeostomeae) and their predation rates

“…It has become a common observation that overhanging areas of artificial structures harbor dense A. aurita polyp colonies (Miyake et al 2002, Matsumura et al 2005, Di Camillo et al 2010, Toyokawa et al 2011, Duarte et al 2012. Dive observations during the present study showed that the natural enemies of A. aurita polyps are common on rocky and pebbled shores outside fishing ports, but are very scarce under suspended structures in port enclosures.…”

“…The polyps can increase their numbers by means of budding, fission and podocyst formation to generate large populations (e.g. Chapman 1968, Coyne 1973, Arai 1997, Han & Uye 2010, Thein et al 2012, particularly on the undersurfaces of artificial structures (Watanabe & Ishii 2001, Miyake et al 2002, Willcox et al 2008, Toyokawa et al 2011, Duarte et al 2012. For example, one polyp with excess food at 26°C can increase in only three weeks to as many as 57 individuals by budding (Uye, unpubl.…”

Rock preference of planulae of jellyfish Aurelia aurita (Linnaeus 1758) for settlement in the laboratory

“…After successful settlement and survival, the prosperity of polyps at that site, and eventual jellyfish blooms, should depend on micro-scale shear stress (Keen 1987), stability of the substrate (Toyokawa et al 2011), and competition with other sessile benthic organisms (Lotan et al 1992). Strength and means of attachment of planulae and polyps onto substrate are not fully understood, and need to be studied further.…”

Population Dynamics of Jellyfish Aurelia aurita (s.l.) in Sihwa Lake

“…그러나 대부분의 현장연구에서 보름달물해파리 부유유생은 동계 에서 춘계에 걸쳐 발생하며 (Lucas and Williams 1994;Miyake et al 1997;Ishii et al 2004;Toyokawa et al 2011), 스웨덴의 Gullmarfjord에서는 추계와 춘계 두 번의 부유유생 발생이 보고되어 있고 (Hernroth and Grändahl 1983), 팔라우의 jellyfish lake에서는 연중 출현하기도 한 다 (Hammer et al 1982). 기존 연구에서는 유성생식에 의한 플라눌라 방출이 성 체의 생리활성도 감소를 초래하여, 개체 크기의 감소와 사 망을 유도함으로써 성체의 출현기간을 제어한다고 하였으 며 (Ishii et al 1995;Lucas 1996), 수온과 먹이량 변화는 플라눌라 방출시기와 방출량을 조절하는 요인이라고 하였 다 (Lucas 1996(Lucas , 2001Hamner and Jenssen 1974;Ishii and Båmstedt 1998;Lucas and Lawes 1998) …”