Sharks and Rays

Incidental shark and ray capture occurs in longline, purse seine and gillnet tuna fisheries. The most effective mitigation measures for longline fisheries include deep-setting, reduced soak time, avoiding wire leaders and hook and bait changes [2], though in applying these, cross-taxa effects need careful consideration. Silky and oceanic whitetip sharks are the most common shark bycatch species in purse seine fisheries, captured mostly when vessels fish on FADs but also through entanglement in FAD netting. Limiting FAD use and modifying FAD designs and practices are the most promising mitigation methods [2]. As with cetaceans, entanglement is a significant problem in medium-scale, semi-industrial and artisanal tuna drift gillnet fisheries. There has been some success with sub-surface gillnets [3] but further validation of this technique is required. For all gear types, safe handling and release procedures have been developed which significantly reduce post-release mortality of sharks, e.g., try to avoid landing sharks onboard; instead bring them close to the vessel and cut line as close to the hook as possible to reduce the length of trailing line [1].

Recent studies have looked at physiological factors affecting post-release mortality of sharks, e.g., stationary-respiring shark species have been shown to experience lower post-release mortality rates than obligate ram-ventilators on longlines [2]. Such information helps to understand the vulnerability of different shark species and thus feeds into improved management strategies for shark bycatch.

For detailed biological and distributional data about shark species, refer to FishBase, Sharkipedia (includes abundance time-series) or Shark-References. FAO has published a series of regional catalogues describing shark/ batoid/chimeras, such as this one for the North Atlantic. Look for others in the series here. NOAA's 'Find a Species - Highly Migratory Species' has information on protection status, biology and population status, distribution, threats, conservation measures and research. See also FAO's database of management measures. Handy species ID guides can be found here.

STAGIS, a database of shark tagging FIELD STUDIES conducted in the Pacific Ocean, can be accessed here.

References

  1. Francis MP, Lyon WS, Clarke SC, et al (2023) Post-release survival of shortfin mako (Isurus oxyrinchus) and silky (Carcharhinus falciformis) sharks released from pelagic tuna longlines in the Pacific Ocean. Aquatic Conservation: Marine and Freshwater Ecosystems 33:366–378. https://doi.org/10.1002/aqc.3920
  2. Dapp DR, Huveneers C, Walker TI, et al (2016) Moving from Measuring to Predicting Bycatch Mortality: Predicting the Capture Condition of a Longline-Caught Pelagic Shark. Front Mar Sci 2:126. https://doi.org/10.3389/fmars.2015.00126
  3. Swimmer Y, Zollett E, Gutierrez A (2020) Bycatch mitigation of protected and threatened species in tuna purse seine and longline fisheries. Endang Species Res 43:517–542. https://doi.org/10.3354/esr01069
  4. Moazzam M (2019) Species composition of elasmobranchs in the surface and subsurface gillnet operation in the Northern Arabian Sea. In: IOTC - 15th Working Party on Ecosystems and Bycatch. IOTC-2019-WPEB15-13, La Saline Les Bains, Reunion Island

     

Sharks

Sharks

3-Alpha Code Name Scientific Name
WSH GREAT WHITE SHARK Carcharodon carcharias
TSK FLAPNOSE HOUNDSHARK Scylliogaleus quecketti
TRB WHITETIP REEF SHARK Triaenodon obesus
TIG TIGER SHARK Galeocerdo cuvier
THR THRESHER SHARKS NEI Alopias spp.
SUN OCELLATED ANGELSHARK Squatina tergocellatoides
SSQ VELVET DOGFISH Scymnodon squamulosus
SPZ SMOOTH HAMMERHEAD Sphyrna zygaena
SPQ SMALLEYE HAMMERHEAD Sphyrna tudes
SPN HAMMERHEAD SHARKS NEI Sphyrna spp.
SPL SCALLOPED HAMMERHEAD Sphyrna lewini
SPK GREAT HAMMERHEAD Sphyrna mokarran
SON PACIFIC SLEEPER SHARK Somniosus pacificus
SMA SHORTFIN MAKO Isurus oxyrhinchus
SKX SHARKS, RAYS, SKATES, ETC. NEI Elasmobranchii
SKH VARIOUS SHARKS NEI Selachimorpha (Pleurotremata)
SCK KITEFIN SHARK Dalatias licha
SBL BLUNTNOSE SIXGILL SHARK Hexanchus griseus
RUZ GREENBACK STINGAREE Urolophus viridis
RUT CROSSBACK STINGAREE Urolophus cruciatus
RSK REQUIEM SHARKS NEI Carcharhinidae
RPZ LONGCOMB SAWFISH Pristis zijsron
RPC DWARF SAWFISH Pristis clavata
RHY AUSTRALIAN SHARPNOSE SHARK Rhizoprionodon taylori
RHN WHALE SHARK Rhincodon typus
RHA MILK SHARK Rhizoprionodon acutus
REO SHARK SUCKER Remora remora
PTH PELAGIC THRESHER SHARK Alopias pelagicus
PSK CROCODILE SHARK Pseudocarcharias kamoharai
PPC LONGNOSE SAWSHARK Pristiophorus cirratus
POR PORBEAGLE SHARK Lamna nasus
OSF ZEBRA SHARK Stegostoma fasciatum
ORZ TAWNY NURSE SHARK Nebrius ferrugineus
ODH BIGEYE SAND TIGER SHARK Odontaspis noronhai
OCS OCEANIC WHITETIP SHARK Carcharhinus longimanus
NTC BROADNOSE SEVENGILL SHARK Notorynchus cepedianus
NGA SICKLEFIN LEMON SHARK Negaprion acutidens
MTL SPOTTED ESTUARY SMOOTH-HOUND Mustelus lenticulatus
MSK MACKEREL SHARKS, PORBEAGLES NEI Lamnidae
MAK MAKO SHARKS Isurus spp.
LMP MEGAMOUTH SHARK Megachasma pelagios
LMD SALMON SHARK Lamna ditropis
LMA LONGFIN MAKO Isurus paucus
LES LEOPARD SHARK Triakis semifasciata
ISB COOKIE CUTTER SHARK Isistius brasiliensis
HXT SHARPNOSE SEVENGILL SHARK Heptranchias perlo
HEG CRESTED BULLHEAD SHARK Heterodontus galeatus
HEE SNAGGLETOOTH SHARK Hemipristis elongatus
HDQ BULLHEAD SHARKS Heterodontiformes
HAH BRISTLY CATSHARK Halaelurus hispidus
GAG SCHOOL SHARK Galeorhinus galeus
FAL SILKY SHARK Carcharhinus falciformis
EUB WINGHEAD SHARK Eusphyra blochii
ETF BLACKBELLY LANTERNSHARK Etmopterus lucifer
DWS DEEP-WATER SHARKS (NEI) Elasmobranchii
DUS DUSKY SHARK Carcharhinus obscurus
DOP SHORTNOSE SPURDOG Squalus megalops
DGZ DOGFISHES NEI Squalus spp
DGX DOGFISH SHARKS NEI Squalidae
DGS PICKED DOGFISH Squalus acanthias
DCA BIRDBEAK DOGFISH Deania calcea
CYU PLUNKET SHARK Scymnodon plunketi
CVX GROUND SHARKS Carcharhiniformes
CTU GUMMY SHARK Mustelus antarcticus
CPU LITTLE GULPER SHARK Centrophorus uyato
CPS DRAUGHTSBOARD SHARK Cephaloscyllium isabellum
CNX WHITENOSE SHARK Nasolamia velox
CHB GHOST SHARK Callorhinchus milii
CEU DUMB GULPER SHARK Centrophorus harrissoni
CEM SMALLFIN GULPER SHARK Centrophorus moluccensis
CCZ CREEK WHALER Carcharhinus fitzroyensis
CCY GRACEFUL SHARK Carcharhinus amblyrhynchoides
CCU AUSTRALIAN BLACKTIP SHARK Carcharhinus tilstoni
CCT GREY NURSE/ SAND TIGER SHARK Carcharius taurus
CCQ SPOTTAIL SHARK Carcharhinus sorrah
CCP SANDBAR SHARK Carcharhinus plumbeus
CCM HARDNOSE SHARK Carcharhinus macloti
CCL BLACKTIP SHARK Carcharhinus limbatus
CCG GALAPAGOS SHARK Carcharhinus galapagensis
CCF PIGEYE SHARK Carcharhinus amboinensis
CCE BULL SHARK Carcharhinus leucas
CCD WHITECHEEK SHARK Carcharhinus dussumieri
CCB SPINNER SHARK Carcharhinus brevipinna
CCA BIGNOSE SHARK Carcharhinus altimus
BTH BIGEYE THRESHER SHARK Alopias superciliosus
BSK BASKING SHARK Cetorhinus maximus
BSH BLUE SHARK Prionace glauca
BRO BRONZE WHALER SHARK Carcharhinus brachyurus
BLR BLACKTIP REEF SHARK Carcharhinus melanopterus
ASK ANGELSHARKS, SAND DEVILS NEI Squatinidae
AML GREY REEF SHARK Carcharhinus amblyrhynchos
ALV COMMON THRESHER SHARK Alopias vulpinus
ALS SILVERTIP SHARK Carcharhinus albimarginatus

Rays

3-Alpha Code Name Scientific Name
WST WHIP STINGRAY Dasyatis akajei
TTF NEW ZEALAND TORPEDO Torpedo fairchildi
TOE TORPEDO RAYS Torpedo spp
STT STINGRAYS, BUTTERFLY RAYS NEI Dasyatidae
STI STINGRAYS NEI Dasyatis spp
SRX RAYS, STINGRAYS, MANTAS NEI Rajiformes
SKX SHARKS, RAYS, SKATES, ETC. NEI Elasmobranchii
SKA RAJA RAYS NEI Raja spp
RTY RIBBONTAIL STINGRAY Taeniura lymma
RMV MOBULA NEI Mobula spp
RMU MUNK'S DEVIL RAY Mobula munkiana
RMT CHILEAN (OR SICKLEFIN) DEVIL RAY Mobula tarapacana
RMO SMOOTHTAIL MOBULA (OR BENTFIN DEVIL RAY) Mobula thurstoni
RMN LESSER GUINEAN DEVIL RAY Mobula rochebrunei
RMM SPINETAIL (OR GIANT) DEVIL RAY Mobula mobular
RMK SHORTHORNED PYGMY (OR SHORTFIN) DEVIL RAY Mobula kuhlii
RMJ* SPINETAIL MOBULA (OR SPINETAIL DEVIL RAY)* Mobula japanica* NOW M. mobular
RMH LESSER (OR ATLANTIC) DEVIL RAY Mobula hypostoma
RME LONGHORNED MOBULA (OR PYGMY DEVIL RAY) Mobula eregoodootenkee
RMB GIANT MANTA Mobula birostris
RMA REEF MANTA RAY Mobula alfredi
RDR SHORT-TAIL STINGRAY Dasyatis brevicaudata
RDK BLUE-SPOTTED STINGRAY Neotrygon kuhlii
PLS PELAGIC STINGRAY Pteroplatytrygon violacea
MYD EAGLE RAY Myliobatis tenuicaudatus
MNT MANTA RAYS Manta spp
MAN MANTAS, DEVIL RAYS NEI Mobulidae
MAE SPOTTED EAGLE RAY Aetobatus narinari
JDT THORNTAIL STINGRAY Dasyatis thetidis
EAG EAGLE RAYS NEI Myliobatidae
BAI BATOID FISHES NEI Batoidimorpha (Hypotremata)