Extinction risk and conservation of the world's sharks and rays.
The rapid expansion of human activities threatens ocean-wide biodiversity. Numerous marine animal populations have declined, yet it remains unclear whether these trends are symptomatic of a chronic accumulation of global marine extinction risk. We present the first systematic analysis of threat for a globally distributed lineage of 1,041 chondrichthyan fishes-sharks, rays, and chimaeras. We estimate that one-quarter are threatened according to IUCN Red List criteria due to overfishing (targeted and incidental). Large-bodied, shallow-water species are at greatest risk and five out of the seven most threatened families are rays. Overall chondrichthyan extinction risk is substantially higher than for most other vertebrates, and only one-third of species are considered safe. Population depletion has occurred throughout the world's ice-free waters, but is particularly prevalent in the Indo-Pacific Biodiversity Triangle and Mediterranean Sea. Improved management of fisheries and trade is urgently needed to avoid extinctions and promote population recovery. DOI: http://dx.doi.org/10.7554/eLife.00590.001.
IUCN Species Survival Commission Shark Specialist Group, Department of Biological Sciences, Simon Fraser University, Burnaby, Canada.
Nicholas K
NK
Dulvy
Sarah L
SL
Fowler
John A
JA
Musick
Rachel D
RD
Cavanagh
Peter M
PM
Kyne
Lucy R
LR
Harrison
John K
JK
Carlson
Lindsay Nk
LN
Davidson
Sonja V
SV
Fordham
Malcolm P
MP
Francis
Caroline M
CM
Pollock
Colin A
CA
Simpfendorfer
George H
GH
Burgess
Kent E
KE
Carpenter
Leonard Jv
LJ
Compagno
David A
DA
Ebert
Claudine
C
Gibson
Michelle R
MR
Heupel
Suzanne R
SR
Livingstone
Jonnell C
JC
Sanciangco
John D
JD
Stevens
Sarah
S
Valenti
William T
WT
White
D000818:Animals; D003247:Conservation of Natural Resources; D053476:Extinction, Biological; D006801:Humans; D009792:Oceans and Seas; D018570:Risk Assessment; D012754:Sharks / Q000254:growth & development*; D012860:Skates, Fish / Q000254:growth & development*
biodiversity change; extinction risk; fishes; life histories; population biology; sharks and rays