HUMAN PROBLEMS RESULTING FROM
JELLYFISH BLOOMS
Stings from pelagic cnidarians cause discomfort and
sometimes medical emergencies for swimmers and
waders primarily in warm marine waters worldwide
(reviewed in Fenner & Williamson 1996, Burnett 2001).
Severe stings result especially from cubomedusae and
from Physalia spp. When pelagic cnidarians occur in
great abundance, stinging can occur at epidemic levels
(Table 1). In many coastal tourist areas, monitoring and
warning systems are used to alert swimmers to potential
encounters with jellyfish (e.g. Bernard et al. 1988,
Decker et al. 2007). As human populations and recreational
activities continue to increase along the coasts,
stinging is projected to become an increasing problem
(Macrokanis et al. 2004). Beaches infested with jellyfish
undoubtedly are detrimental to tourist appeal.
Jellyfish also present stinging hazards to fishermen as
they pull fishing gear on board and to aquaculturists
(Sharp 2001).
Interference with fishing operations is the most frequently
reported problem occurring with great abundances
of jellyfish (Table 2). Large catches of jellyfish
can split the fishing nets and ruin the quality of the
catch (Fig. 2). Such problems have been particularly
acute for Japan since 1990 when Aurelia aurita
increased in the Seto Inland Sea, and since 2002 in
coastal waters where Nomura’s jellyfish has bloomed
annually and severely interfered with set-net fisheries.
Such problems apparently are more widespread than
reported in the literature, as suggested by the many
jellyfish-exclusion devices used with fishing gear (e.g.
Mohr & Rauck 1978, Broadhurst & Kennelly 1996,
Anonymous 1997b, Wienbeck 1998, Van Marlen et al.
2001, Matsushita & Honda 2006).Jellyfish kill fish in aquaculture pens, with problems
reported especially in Japan and Scotland (Table 3).
Small jellyfish and tentacles of large species enter the
fish pens and irritate the fish gills resulting in hemorrhage
and subsequent suffocation (Johnston et al.
2005). Decapod culture also has been reported to be
affected adversely by jellyfish blooms in India and the
USA (Table 3).Jellyfish also clog seawater intake screens of power
and desalination plants causing power reductions and
shutdowns (Table 4). This has been a long-standing
problem in Japan where large near-shore populations
of Aurelia aurita (s. l.) jellyfish occur. Similar problems
have been reported from other countries. Jellyfish
clogging requires ongoing maintenance; one power
plant in Japan has maintained records of the jellyfish biomass cleaned daily from the intake screens, providing
a decade-long record of jellyfish abundance
(Kaneda et al. 2007). Clogging incidents can cause
emergency situations at nuclear power plants (NPPs)
and can result in significant power loss and economic
damage to affected cities. To prevent clogging events,
studies on potential threats of jellyfish and on methods
to detect and deflect them from the intakes have been
investigated (Marks & Cargo 1974, Marks 1975, Toda
et al. 1995, Azis et al. 2000, Lee et al. 2006).
HUMAN PROBLEMS RESULTING FROMJELLYFISH BLOOMSStings from pelagic cnidarians cause discomfort andsometimes medical emergencies for swimmers andwaders primarily in warm marine waters worldwide(reviewed in Fenner & Williamson 1996, Burnett 2001).Severe stings result especially from cubomedusae andfrom Physalia spp. When pelagic cnidarians occur ingreat abundance, stinging can occur at epidemic levels(Table 1). In many coastal tourist areas, monitoring andwarning systems are used to alert swimmers to potentialencounters with jellyfish (e.g. Bernard et al. 1988,Decker et al. 2007). As human populations and recreationalactivities continue to increase along the coasts,stinging is projected to become an increasing problem(Macrokanis et al. 2004). Beaches infested with jellyfishundoubtedly are detrimental to tourist appeal.Jellyfish also present stinging hazards to fishermen asthey pull fishing gear on board and to aquaculturists(Sharp 2001).Interference with fishing operations is the most frequentlyreported problem occurring with great abundancesof jellyfish (Table 2). Large catches of jellyfishcan split the fishing nets and ruin the quality of thecatch (Fig. 2). Such problems have been particularlyacute for Japan since 1990 when Aurelia auritaincreased in the Seto Inland Sea, and since 2002 incoastal waters where Nomura’s jellyfish has bloomedannually and severely interfered with set-net fisheries.Such problems apparently are more widespread thanreported in the literature, as suggested by the manyjellyfish-exclusion devices used with fishing gear (e.g.Mohr & Rauck 1978, Broadhurst & Kennelly 1996,Anonymous 1997b, Wienbeck 1998, Van Marlen et al.2001, Matsushita & Honda 2006).Jellyfish kill fish in aquaculture pens, with problemsreported especially in Japan and Scotland (Table 3).Small jellyfish and tentacles of large species enter thefish pens and irritate the fish gills resulting in hemorrhageand subsequent suffocation (Johnston et al.2005). Decapod culture also has been reported to beaffected adversely by jellyfish blooms in India and theUSA (Table 3).Jellyfish also clog seawater intake screens of powerand desalination plants causing power reductions andshutdowns (Table 4). This has been a long-standingproblem in Japan where large near-shore populationsof Aurelia aurita (s. l.) jellyfish occur. Similar problemshave been reported from other countries. Jellyfishclogging requires ongoing maintenance; one powerplant in Japan has maintained records of the jellyfish biomass cleaned daily from the intake screens, providinga decade-long record of jellyfish abundance(Kaneda et al. 2007). Clogging incidents can causeemergency situations at nuclear power plants (NPPs)and can result in significant power loss and economicdamage to affected cities. To prevent clogging events,studies on potential threats of jellyfish and on methods
to detect and deflect them from the intakes have been
investigated (Marks & Cargo 1974, Marks 1975, Toda
et al. 1995, Azis et al. 2000, Lee et al. 2006).
การแปล กรุณารอสักครู่..