Reader's Digest

July• 2018 | 71

READER’S DIGEST

Hawaii’s shores and are a familiar
food for tiger sharks. With wide jaws
andheavyangledteethtigersharks
areabletocrushandslicethrough
anadultturtle’sshellinawaymost
sharks can’t. So if more turtles are
sharingthewaterwithmorepeople
more shark bites might be the result.
The relationship between tiger
sharks and sea turtles could have
broadimplicationsforthehealthof
oceanecosystemsaroundtheglobe.
OnaremotepartofAustralia’s
westerncoastcalledSharkBaya
research team led by Mike Heithaus
of Florida International University
has documented how tiger sharks
prevent sea turtles and dugongs (sea
cows) from overgrazing the sea grass
beds that anchor the ecosystem. It’s
notjustbyeatingtheanimalsthey
discovered. The presence of the
sharks changes the turtles’ and du-
gongs’ habits forcing them to graze
more judiciously to lessen their risk.
IntheBahamaswhichdesignated
itswatersasharksanctuaryin2011
themarineecosystemsarerelatively
healthy. But the adjacent western
Atlantichasmuchweakersharkpro-
tections and appears to be sufering
the consequences.
“I do work in Florida and the Baha-
masandit’snightandday”saysNeil
Hammerschlag a marine ecologist
attheUniversityofMiami.“Wesee
massive differences in the size and

numbersofthesharks.hey’redoing

wellintheBahamasbutwealmost

never catch them of Florida. hey’re

just80kilometresapart”headded.

Floridaprohibitedthekillingoftiger

sharksinitswatersin2012butit’s

the only state on the United States'

easternseaboardtohavedoneso.

JAWSISN’T RESPONSIBLEfor

mostofthethreatstigersharksface

• coastal development marine pollu-
  tion longline ishing the popularity
  ofsharkinsoup–butitdidcreatea
  cultural attitude that has had a long
  shelf life. AfterJawspeopledidn’t
  just become paranoid about sharks;
  they became callous even vengeful.
  Shark-ishing tournaments sprouted
  on the eastern seaboard of the
  United States and dozens continue
  celebratingthespectacleof‘monster
  sharks’ hanging on the docks.
  Insummer2015asIwasplanning
  mydiveatTigerBeachnewsbroke
  that an 360-kilogram tiger shark had
  beencaughtofftheSouthCarolina
  coast.USA Todaycalled the shark
  “monstrous”anddescribedtheish-
  ermen as “brave”. When I got home
  fromHawaiiIlookedatthestory
  again. Seeing the picture of the gut-
  ted delated shark I thought about
  howitwasoncethesamesizeas
  Sophie and those weren’t at all the
  wordsthatcametomind–foreither
  thesharkorthemenwhokilledit.

FROM NATIONAL GEOGRAPHICSERVICES. NATIONALGEOGRAPHIC.COMMAGAZINE (JUNE 2016) © NATIONAL GEOGRAPHIC CREATIVE