Neil Aldridge / Blindfolded and tranquilised adult White rhinoceros (Ceratotherium simum) with a tracking tag lies and recovers in the Okavango Delta, northern Botswana, following a translocation operation that invol...

Jordi Chias / Juvenile Hawksbill turtle (Eretmochelys imbricata) released by biologist after being tagged, Cayman; Cayman Islands Archipelago.

Juergen Freund / Chambered nautilus (Nautilus pompilius) with radio transmitter, Indo-pacific

Juergen Freund / Richard Fitzpatrick releases Grey reef shark {Carcharhinus amblyrhynchos} after inserting transmitter into its belly, as part of the Coral Reef census, Lizard Island, Queensland, Australia, April 2008

Claudio Contreras / California condor (Gymnogyps californianus) group feeding on carrion at feeding site, California condor recovery program. Sierra de San Pedro Martir National Park, Baja California Peninsula, Mexico. 2...

Claudio Contreras / California condor (Gymnogyps californianus) in flight, wings radio tagged. California condor recovery program, Sierra de San Pedro Martir National Park, Baja California Peninsula, Mexico. 2011.

Claudio Contreras / California condor (Gymnogyps californianus) in flight, wings radio tagged. California condor recovery program, Sierra de San Pedro Martir National Park, Baja California Peninsula, Mexico. 2011.

Claudio Contreras / California condor (Gymnogyps californianus) in flight, wings radio tagged. California condor recovery program, Sierra de San Pedro Martir National Park, Baja California Peninsula, Mexico. 2011.

Claudio Contreras / California Condor (Gymnogyps californianus) standing on rock, radio tagged. California condor recovery program, Sierra de Sierra de San Pedro Martir National Park, Baja California Peninsula, Mexico. 2...

Claudio Contreras / California Condor (Gymnogyps californianus) standing on rock, radio tagged. California condor recovery program, Sierra de San Pedro Martir National Park, Baja California Peninsula, Mexico.

Claudio Contreras / California condor (Gymnogyps californianus) juvenile in flight, wings radio tagged. California condor recovery program in Mexico, Sierra de San Pedro Martir National Park, Baja California Peninsula, M...

Francisco Marquez / Close up of the tag on a Greater flamingo (Phoenicopterus ruber) juvenile's leg, held by a volunteer, Fuente de Piedra lagoon, Malaga, Spain. August.

SCOTLAND: The Big Picture / Field workers attaching radio transmitter to young Golden eagle (Aquila chrysaetos) chick for satellite tracking, Cairngorms National Park, Scotland, UK, June.

SCOTLAND: The Big Picture / Field workers attaching radio transmitter to young Golden eagle (Aquila chrysaetos) chick for satellite tracking, Cairngorms National Park, Scotland, UK, June.

SCOTLAND: The Big Picture / Golden eagle (Aquila chrysaetos) chick in nest after having a radio transmitter fitted for the purpose of satellite tracking the bird's movements, Cairngorms National Park, Scotland, UK, June.

SCOTLAND: The Big Picture / Field worker abseiling to Golden eagle (Aquila chrysaetos) nest to return a recently satellite-tagged chick, Cairngorms National Park, Scotland, UK, June.

SCOTLAND: The Big Picture / Field worker abseiling to Golden eagle (Aquila chrysaetos) nest to return a recently satellite-tagged chick, Cairngorms National Park, Scotland, UK, June.

SCOTLAND: The Big Picture / Field worker abseiling to Golden eagle (Aquila chrysaetos) nest to return a recently satellite-tagged chick, Cairngorms National Park, Scotland, UK, June.

SCOTLAND: The Big Picture / Golden eagle (Aquila chrysaetos) chick with radio transmitter fitted for the purpose of satellite tracking the bird's movements, Cairngorms National Park, Scotland, UK, June.

SCOTLAND: The Big Picture / Field workers attaching radio transmitter to young Golden eagle (Aquila chrysaetos) chick for satellite tracking, Cairngorms National Park, Scotland, UK, June.

SCOTLAND: The Big Picture / Field workers attaching radio transmitter to young Golden eagle (Aquila chrysaetos) chick for satellite tracking, Cairngorms National Park, Scotland, UK, June.

SCOTLAND: The Big Picture / Field workers attaching radio transmitter to young Golden eagle (Aquila chrysaetos) chick for satellite tracking, Cairngorms National Park, Scotland, UK, June.

SCOTLAND: The Big Picture / Golden eagle (Aquila chrysaetos) chick with radio transmitter fitted for the purpose of satellite tracking the bird's movements, Cairngorms National Park, Scotland, UK, June.

SCOTLAND: The Big Picture / Golden eagle (Aquila chrysaetos) chick with radio transmitter fitted for the purpose of satellite tracking the bird's movements, Cairngorms National Park, Scotland, UK, June.

Doug Gimesy / Researcher holding a Platypus (Ornithorhynchus anatinus) which is recovering from an in-field anesthetic. It was anaesthetised to allow a radio transponder to be glued to its tail - allowing researche...

Claudio Contreras / American Bison (Bison bison) with tagged ear, Janos Biosphere Reserve, northern Mexico, October

Will Burrard-Lucas / Black and white image of people fitting radio tracking collar onto African elephant (Loxodonta africana) Tsavo Conservation Area, Kenya. Editorial use only.

Will Burrard-Lucas / Black and white image of people fitting radio tracking collar onto African elephant (Loxodonta africana) Tsavo Conservation Area, Kenya. Editorial use only.

Will Burrard-Lucas / Black and white image of people fitting radio tracking collar onto African elephant (Loxodonta africana) Tsavo Conservation Area, Kenya. Editorial use only.

Will Burrard-Lucas / Black and white image of people viewed through sedated African elephant (Loxodonta africana) tusks during radio collaring operation. Tsavo Conservation Area, Kenya. Editorial use only.

Karine Aigner / Nano - transmitters and the 'back pack' made by scientist Nathan Cooper, in comparison, next to a dime. Used for research into migration and behaviour of Kirtland's warblers.

Stephane Granzotto / Whale shark (Rhincodon typus) with tracking tag, Tadjourah Gulf, Republic of Djibouti.

Stephane Granzotto / Whale shark (Rhincodon typus) with tracking tag, Tadjourah Gulf, Republic of Djibouti.

Stephane Granzotto / Snorkeller taking pictures of Whale shark (Rhincodon typus) with tracking tag, Tadjourah Gulf, Republic of Djibouti. December, 2017.

Stephane Granzotto / Scuba diver checking on Whale shark (Rhincodon typus) tracking tag, Tadjourah Gulf, Republic of Djibouti.

Stephane Granzotto / Whale shark (Rhincodon typus) with satellite tracking tag, Tadjourah Gulf, Republic of Djibouti. December 2017.

Claudio Contreras / Caribbean flamingo (Phoenicopterus ruber) juvenile, about to be tagged and released to the wild, captive, Ria Lagartos Biosphere Reserve, Yucatan Peninsula, Mexico, September

Claudio Contreras / Caribbean flamingo (Phoenicopterus ruber) juvenile, tagged and released to the wild, captive, Ria Lagartos Biosphere Reserve, Yucatan Peninsula, Mexico, September

Magnus Lundgren / Wild Wonders of China / Yellow seahorse (Hippocampus kuda) is tagged underwater for OPCF's program. Hoi Ha Wan Marine Park, Hong Kong, China.

Magnus Lundgren / Wild Wonders of China / Yellow seahorse (Hippocampus kuda) is tagged underwater for OPCF reseach program program. Hoi Ha Wan Marine Park, Hong Kong, China. June, 2016.

Magnus Lundgren / Wild Wonders of China / Yellow seahorse (Hippocampus kuda) with tag, Hoi Ha Wan Marine Park, northeast coast, New territories, Hong Kong, China.

Karine Aigner / Biologist about to harness Hermit thrush (Catharus guttatus) with nano-transmitter. Block island, Rhode Island, USA.

Karine Aigner / Biologist harnessing a Hermit thrush (Catharus guttatus) with nano-transmitter. Block island, Rhode Island, USA.

Karine Aigner / Hermit thrush (Catharus guttatus) wearing a barely visible nano-transmitter. Block island, Rhode Island, USA.

Karine Aigner / Hermit Thrush (Catharus guttatus) held in hand before release - wearing a barely visible nano-transmitter. Block island, Rhode Island, USA.

Karine Aigner / Nano transmitter for songbirds, with loop harness. Block island, Rhode Island, USA.

Tony Heald / Elephant (Loxodonta africana), male standing on hind legs to reach acacia pods with Cattle egrets (Bubulcus ibis) in background. Mana Pools National Park, Zimbabwe.

Tony Heald / Elephant (Loxodonta africana), male standing on hind legs to reach acacia pods. Cattle egrets (Bubulcus ibis) around elephant's feet. Mana Pools National Park, Zimbabwe.

Tony Heald / African wild dog (Lycaon pictus) walking through grassland with radio collar showing. Mana Pools National Park, Zimbabwe.

Jeff Foott / Wild California condor (Gymnogyps californianus) in flight, with wing tag and transmitter, Baja, Mexico.

Jeff Foott / Wild California condor (Gymnogyps californianus) in flight, with wing tag and transmitter, Baja, Mexico.

Jeff Foott / Wild California condor (Gymnogyps californianus) in flight, with wing tag and transmitte, Baja, Mexico.

Jeff Foott / Wild California condor (Gymnogyps californianus) in flight, with wing tag and transmitte, Baja, Mexico.

Charlie Summers / Greenback cut throat trout (Oncorhynchus clarkii stomias) in their spawning stream in the Neota Wilderness area of Colorado, USA, July. Significant in this is are the Visible Implant Elastomer Tags (...

Mike Potts / Hookers or New Zealand sealion (Phocarctos hookeri) tagged pups at beach colony. Sandy Bay. Enderby Island. Auckland Islands. Subantarctic New Zealand.

Mike Potts / Hookers or New Zealand sealion (Phocarctos hookeri) tagged pups at beach colony. Sandy Bay. Enderby Island. Auckland Islands. Subantarctic New Zealand.

Ann & Steve Toon / Hebridean sheep, rare breed used in conservation grazing, Caerlaverock Wildfowl and Wetland Trust reserve, Dumfries and Galloway, Scotland, UK, November.

Nick Hawkins / Woodland caribou (Rangifer tarandus caribou) with tracking collar round neck, Fogo Island, Newfoundland, Canada, October, Endangered species.

Nick Hawkins / Woodland caribou (Rangifer tarandus-caribou) with radio collat round neck, Fogo Island, Newfoundland, Canada, October, Endangered species.

Nick Upton / Bewick's swan (Cygnus columbianus) adult pair with one wearing a GPS logging neck collar for satellite tracking of migratory movements, WWT Slimbridge, Gloucestershire, UK, February.

Roger Powell / Ruddy turnstone (Arenaria interpres) feeding on beach. Radio tagged to identify its migration route. Druridge Bay, Northumberland, England, UK, February

Lynn M. Stone / Tagged Monarch butterfly (Danaus plexippus) on Dahlia flower, October. Waterford, Connecticut, USA (non-ex)

Alex Mustard / Great hammerhead shark (Sphyrna mokarran) female cruises over the sand in shallow water. South Bimini, Bahamas. The Bahamas National Shark Sanctuary. Gulf Stream, West Atlantic Ocean.

Suzi Eszterhas / Koala (Phascolarctos cinereus) juvenile orphaned as baby and now awaiting release, Koala Hospital, Port Macquerie, Australia, captive.

Doug Perrine / Hawaiian monk seal (Neomonachus schauinslandi) recently weaned male (aged 56 days) swimming with flipper tags and GPS satellite transmitter. Keokea Beach Park, North Kohala, Hawaii, USA, January 2014....

Doug Perrine / NOAA researcher Mark Sullivan releases a recently weaned male Hawaiian monk seal (Neomonachus schauinslandi) after attaching flipper tags and GPS satellite transmitter at Keokea Beach Park, North Koha...

Doug Perrine / Adult male Hawaiian monk seal (Neomonachus schauinslandi) investigating satellite tag on recently weaned male pup, Keokea Beach Park, North Kohala, Hawaii, USA, January 2014. Critically Endangered spe...

Alex Mustard / Researcher holding up an acoustic shark tag, which is surgically implanted into the belly of a shark and monitored by listening stations on the seabed. Bimini Biological Field Station, Bimini, Bahamas...

Sylvain Cordier / Southern elephant seal (Mirounga leonina) female with pup, Sea Lion Island, Falkland Islands

Barrie Britton / California condor (Gymnogyps californianus), Grand Canyon, Arizona, USA.

Barrie Britton / California condor (Gymnogyps californianus), Grand Canyon, Arizona, USA.

Alex Mustard / Hawksbill turtle (Eretmochelys imbricata) cruising along the drop off of a coral reef. Bloody Bay Wall, Little Cayman, Cayman Islands. British West Indies. Caribbean Sea. Note that this turtle has two...

SCOTLAND: The Big Picture / Tags used by the Spey Fishery Board when releasing Atlantic salmon (Salmo salar) from hatchery into the wild, Scotland, UK, November.

Espen Bergersen / Killer whale / Orca (Orcinus orca) male tagged with satelite transmitter on dorsal fin, Kvaloya, Norway February

Sam Hobson / Lesser black-backed gull chick (Larus fuscus) held by bird ringer. Flatholm Island, Wales, UK. July

Merryn Thomas / Llama (Lama glama) in Andes Mountains, Inca Trail, Peru. December 2013.

Chris & Monique Fallows / Great white shark (Carcharodon carcharias), showing satellite tag in dorsal fin, Seal Island, False Bay, South Africa, June.

Cyril Ruoso / Inmate in Cedar Creek Correction Center, checking for microchip in Oregon Spotted Frog (Rana pretiosa). Prisoners in this facility are raising endangered frogs for release in the wild, as part of the...

Cyril Ruoso / Inmate in Cedar Creek Correction Center, checking for microchip in Oregon Spotted Frog (Rana pretiosa). Prisoners in this facility are raising endangered frogs for release in the wild, as part of the...

Cyril Ruoso / Inmate in Cedar Creek Correction Center, checking for microchip in Oregon Spotted Frog (Rana pretiosa). Prisoners in this facility are raising endangered frogs for release in the wild, as part of the...

Cyril Ruoso / Biologist Mark Hayes looking at Oregon Spotted Frog (Rana pretiosa) raised by inmates in the Cedar Creek Correction Center. Prisoners in this facility are raising endangered frogs for release in the w...

Cyril Ruoso / Biologist implanting microchip into Oregon Spotted Frog (Rana pretiosa) raised by inmates in the Cedar Creek Correction Center. Prisoners in this facility are raising endangered frogs for release in t...

Cyril Ruoso / Inmate in Cedar Creek Correction Center, checking for microchip in Oregon Spotted Frog (Rana pretiosa). Prisoners in this facility are raising endangered frogs for release in the wild, as part of the...

Cyril Ruoso / Biologist Mark Hayes looking at Oregon Spotted Frog (Rana pretiosa) raised by inmates in the Cedar Creek Correction Center. Prisoners in this facility are raising endangered frogs for release in the w...

Pete Oxford / MAR Alliance research team returning tagged Caribbean reef shark (Carcharhinus perezi) to water after collecting samles to determine methyl mercury levels. Lighthouse Reef Atoll, Belize. May 2015.

Pete Oxford / Great Hammerhead shark (Sphryna mokarran) with fin mounted ARGOS satellite transponder by MAR Alliance, Lighthouse Reef Atoll, Belize. May 2015.

Pete Oxford / Hawksbill Turtle with Satellite tag (Eretmochelys Imbricata) for monitoring. Tagged by MAR Alliance, Lighthouse Reef Atoll, Belize.

Nick Upton / Microchipped Harvest mouse (Micromys minutus) leaving a grain feeding station equipped with an automatic Radio Frequency Identification (RFID) monitor which logs visits by mice after release into a fi...

Nick Upton / Microchipped Harvest mouse (Micromys minutus) entering a grain feeding station equipped with an automatic Radio Frequency Identification (RFID) monitor which logs visits by released mice in field site...

Nick Upton / Researcher checking transponder code on microchipped Harvest mouse (Micromys minutus) prior to release, Moulton College, Northampton, UK, June. Model released.

Nick Upton / Researcher checking transponder code on microchipped Harvest mouse (Micromys minutus) prior to release, Moulton College, Northampton, UK, June. Model released.

Nick Upton / Eurasian beaver (Castor fiber) adult female with ear tag, swimming on the River Otter at night, near where it was released by the Devon Wildlife Trust, Devon, UK, August 2015. Photoraphed by infra re...

Nick Upton / Eurasian beaver (Castor fiber) adult female with ear tag, swimming on the River Otter, near where it was released by the Devon Wildlife Trust, Devon, UK, August 2015.

Nick Upton / Adult male Eurasian beaver (Castor fiber) with identifying ear tag swimming at sunset among felled trees dammed stream within large enclosure, Devon Beaver Project, run by Devon Wildlife Trust, Devon,...

David Kjaer / Great bustard (Otis tarda) male 'Pk2' displaying to female 'Pk17', Salisbury Plain, Wiltshire, UK, March.

Doug Perrine / Volunteers restraining a recently weaned male Hawaiian monk seal (Neomonachus schauinslandi) while NOAA researcher Mark Sullivan glues a GPS satellite transmitter onto the fur on the seal's back. Keok...