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Bioelectromagnetism

changes in behavior or mortalities were observed (Cada et al., 2012). It is possible that the frequencies

and intensities of the induced electrical signals created by the strong, 60 Hz EMF in the experiments

were beyond the range that is readily detected by paddlefsh (Cada et al., 2012).

Te electricity produced by ofshore wind turbines is transmitted by cables over long distances

(European Wind Energy Association, 2009). Te electric current generated produces MFs. Studies of

possible efects of artifcial SMFs have been carried out on various species under various experimental

conditions (European Wind Energy Association, 2009). Anthropogenic and artifcial EMFs could inter­

act with marine organisms to produce detectable changes (European Wind Energy Association, 2009).

Usually, however, only very slight diferences in control groups have been recorded (European Wind

Energy Association, 2009).

As the stock of sharks and rays is declining worldwide greatly, preserving eforts have been made to

reduce their catch. When a magnet is attached to the fshing gear, the bycatch of sharks and rays is signif­

cantly reduced by attaching magnets to basket fshing gear and hooks. Since the MF intensity of the attached

magnets is quite strong (e.g., 150 mT) relative to the GMF or localized MFs, it is thought that sharks and rays

with a sensitive MF sensation dislike strong MFs (Stoner and Kaimmer, 2008; Richards et al., 2018).

Te MF may afect mollusks, crustaceans, fsh, and marine mammals that use the GMF for orienta­

tion during navigation. But it is still unknown whether the MFs associated with wind turbines infu­

ence marine organisms (Gill, 2005). Electrosensitive species could be attracted or repelled by the EFs

generated by submarine cables. Special attention must be paid in areas of breeding, feeding, or nursing

because of the congregation or dispersion of sensitive individuals in the benthic community (Gill, 2005).

It is reported that the survival rate of several benthic organisms exposed to SMF of 3.7 mT for several

weeks as well as the reproduction rate of mussels living under these SMF conditions for 3 months did not

present signifcant diferences with the control group (Bochert and Zettler, 2004). From these results,

conclusions are that SMFs of power cable transmissions don’t seem to infuence the orientation, move­

ment, or physiology of the tested benthic organisms (Köller et al, 2006; Meißner, 2006).

Trański et al. (2005) reported that the catch rate of spinycheek crayfshes (Orconectes limosus) was

improved by attaching a magnet to the fshing gear, so the infuence of the SMF on crayfsh sheltering

behavior was particularly apparent. Te average catch increased 1.6 times when a magnet was attached

to the entrance of a tubular trap for crayfshes (Trański et al., 2005). Te MFs at 1 cm and 10 cm from the

entrance of the tubular trap were 410 and 190 μT, respectively (Trański et al., 2005), and therefore, it

seems likely that the magnetic sensory threshold can be estimated.

Fish in the Gulf of Mexico position themselves over buried oil pipelines of the shore of Texas, ori­

enting themselves directly above the buried pipeline at a height of 1–3 m above the seabed and perpen­

dicular to the axis of the pipeline (Arnason et al., 2002). Presumably, they are responding to some EMF

stimuli, such as remnant magnetism in pipeline sections, voltage gradient induced by corrosion protec­

tion devices, or transient signals induced into the pipeline by remote lightning or solar wind-induced

magnetic storms (Arnason et al., 2002).

Te EMFs of both types of cable (bipolar and concentric) used in marine wind farms are small or

zero. It has been reported that the EMFs of submarine cables have no signifcant impacts on the marine

environment (Köller et al, 2006; Meißner, 2006). Studies with a long-term perspective are necessary

to confrm the negligible impact of EMFs of wind energy on marine ecosystems (Köller et al, 2006;

Meißner, 2006). Based on the fndings obtained on the MF sensing mechanism of living organisms,

further multifaceted and detailed research will be required on the basis of the efects of EMF on marine

organisms.

6.2.3 Magnetic Sense of Plants

Plants known to sense light of various wavelengths, respond to gravity, and respond to contact and

electrical signals are subject to the efects of the GMF (Mafei, 2014). Terefore, it has been reported that

plants use the GMF as a physiological modulator (Mafei, 2014). As a pioneer study on the efects of MFs