Californian photographer and conservationist Octavio Aburto had spent years photographing the school in Cabo Pulmo National Park, Mexico – and had been trying to capture this exact shot for three years. “Together with my friend David Castro, we were diving with a large group of Bigeye travellies at Cabo Pulmo National Park, Mexico. Thousands of fish forming a ball during the reproduction courtship. In the afternoon, these fish congregate to form a large spawning aggregation around the reefs of the National Park”. (Photo and caption by Octavio Aburto)

Monaco's Princess Charlotte Casiraghi arrives to attend a mass at the Saint Nicholas Cathedral during the celebrations marking Monaco's National Day, on November 19, 2016 in Monaco. (Photo by Valery Hache/Reuters)

Pashtan Wagner, a Blue Oriental Cat participates in the GCCF Supreme Cat Show at National Exhibition Centre on October 28, 2017 in Birmingham, England. (Photo by Shirlaine Forrest/WireImage)

A hippopotamus is sprayed with water on a hot summer day at Anna National Zoological Park in Chennai, India on April 26, 2017. (Photo by Arun Sankar/AFP Photo)

A hummingbird is photographed during the National Orchid Exhibition at the Jose Celestino Mutis Botanical Garden in Bogota, Colombia Septermber 20, 2018. Picture taken September 20, 2018. (Photo by Luisa Gonzalez/Reuters)

The 33rd All Women Lifeguard Tournament held at Sandy Hook Gateway National Recreation Area in Sandy Hook New Jersey. Wednesday, July 26th, 2017 (Photo by Anthony Causi)

Elizabeth Mills jumps in front of the Conservative Political Action Conference (CPAC) sign at National Harbor, Md., February 23, 2018. (Photo by Joshua Roberts/Reuters)

The shortlist for the coveted Bird Photographer of the Year awards has been announced by Nature Photographers and the British Trust for Ornithology. Here: Red-billed oxpecker on an impala, Kruger National Park, South Africa. (Photo by Edmund Aylmer/BPOTY/Cover Images/The Guardian)