Gary Bell/ Oceanwide / Porcupinefish (Diodon nicthemerus) in defensive posture, Port Phillip Bay, Mornington Peninsula, Victoria, Australia

David Fleetham / Guineafowl pufferfish (Arothron meleagris) puffed up in defence, Hawaii.

Alex Mustard / Colourful reef scene with Coral grouper (Cephalopholis miniata), map puffer (Arothron mappa) and Panda butterflyfish (Chaetodon adiergastos). Tank Reef, Fiabacet Islands, Misool, Raja Ampat, Indonesia...

Georgette Douwma / Guineafowl puffer fish (Arothron meleagris) also known as the Golden puffer or Spotted puffer because is has three colour phases which differ dramatically. Maldives, Indian Ocean

Alex Mustard / Sharpnose puffer (Canthigaster rostrata) portrait with the eyes standing out against a dark background, East End, Grand Cayman, Cayman Island, British West Indies, Caribbean Sea.

Juergen Freund / Vendors selling fish (including Pufferfish) in the Wangi Wangi afternoon public market. Wakatobi, Sulawesi, Indonesia, November 2009.

Juergen Freund / Detail eye and skin of a Pufferfish, West Papua, Indonesia.

Juergen Freund / Giant / Map pufferfish (Arothron mappa) swimming in the reef. Misool, Raja Ampat, West Papua, Indonesia, January

Juergen Freund / Close up of face of inflated pufferfish {Arothron sp}, Indo-Pacific

Jeff Rotman / Black Blotched Porcupinefish (Diodon liturosus) inflated swimming in open ocean. Sipadan Islands, South China Sea.

Juergen Freund / Pufferfish (Arothron) inflated Indo-Pacific

Fred Bavendam / Porcupinefish (Diodon nicthemerus) swallows water to puff itself up and points its spines outward as a defense against predators, South Australia