Male black grouse (Lyrurus tetrix) fighting on snow covered field, Finland

Juvenile grey heron (Ardea cinerea) in flight, escaping from an aggressive rival in a territorial dispute, Rutland Water, Rutland, England, United Kingdom, Europe

Adult bull southern elephant seals (Mirounga leonina) fighting for breeding grounds on South Georgia Island, Southern Ocean

Adult red-footed booby (Sula sula) being attacked in flight by a great frigatebird (Fregata minor) in the Galapagos, UNESCO World Heritage Site, Ecuador, South America

Antarctic fur seal bulls (Arctocephalus gazella) fighting for mating territory on South Georgia, Southern Ocean, Polar Regions

Adult Brunnich's guillemots (Uria lomvia) in a territorial dispute at Alkefjellet, Spitsbergen, Svalbard, Norway, Europe

A combative male iguana bloodied in territorial battle. Santiago Island, Galapagos.S(marine iguana)S(territorial dispute)S(Galapagos)S(UW)

Red fox (Vulpes vulpes) males in territorial confrontation. Montreal Botanical Garden. Quebec. Canada