Solvin Zankl / After an incubation period of 45 to 55 days a first hatchling Green turtle (Chelonia mydas) emerges out of the sand, Bonaire, Leeward Antilles, Caribbean region, Netherlands Antilles

Solvin Zankl / After an incubation period of 45 to 55 days a first hatchling Green turtle (Chelonia mydas) emerges out of the sand, Bonaire, Leeward Antilles, Caribbean region, Netherlands Antilles

David Tipling / King penguin (Aptenodytes patagonicus) turning egg during incubation. Gold Harbour, South Georgia.

Will Watson / Wood pigeons (Columba palumbus) swapping incubation duty on nest, Downy birch (Betula pubescens), Herefordshire, England, UK, October.

Melvin Grey / Black-necked grebe (Podiceps nigricollis) female at nest uncovering eggs for incubation. Danube Delta, Romania, May.

Mark Hamblin / 2020VISION / Female Red-throated diver (Gavia stellata) incubating eggs, Shetland Isles, Scotland, UK, June.

Ramon Navarro / Stone curlew (Burhinus oedicnemus) appoaching nest and settling on eggs, Seville, Spain, June.

Ramon Navarro / Stone curlew (Burhinus oedicnemus) settling on eggs, opening and closing beak, Seville, Spain, June.

Ramon Navarro / Stone curlew (Burhinus oedicnemus) walking to nest and settling on eggs, Seville, Spain, June.

Nick Upton / Common / Eurasian crane (Grus grus) Chris, released by the Great Crane Project, standing in a sedge pool as her mate Monty stands on their nest after taking over incubation duties from her, Slimbridge...

Nick Upton / Common / Eurasian crane (Grus grus) Chris, released by the Great Crane Project, smearing mud on her back - a typical behaviour of nesting cranes - as her mate Monty stands on their nest after taking...

Nick Upton / Common / Eurasian crane (Grus grus) Monty, released by the Great Crane Project, at his nest site in a sedge marsh, ready to relieve his mate Chris of incubation duties, Slimbridge, Gloucestershire, UK...