Terry Whittaker / Man sorting seabird eggs, including those of Common guillemots (Uria aalge) into egg boxes, Skoruvikurbjarg cliffs, Langanes Peninsula, Iceland, May.

Nick Turner / Goose eggs in boxes on a blue checked tablecloth, Cirencester Farmers Market, Cirencester, Gloucestershire, UK, July 2011.

Terry Whittaker / Two men on cliff top with Common guillemot / murre (Uria aalge) eggs collected from cliff face. Skoruvikurbjarg cliffs, Langanes Peninsula, Iceland. May 2018.

Terry Whittaker / Common murre / guillemot (Uria aalge) and Black-legged kittiwake (Rissa tridactyla) eggs in box and egg boxes. Collected from Skoruvikurbjarg cliffs, Langanes Peninsula, Iceland. May 2018.

Terry Whittaker / Seabird eggs including those of Common murre/ guillemot (Uria aalge) in fridge. Collected from Skoruvikurbjarg cliffs, Langanes Peninsula, Iceland. May 2018.

Terry Whittaker / Common murre / guillemot (Uria aalge) eggs in box. Foraged from Skoruvikurbjarg cliffs, Langanes Peninsula, Iceland. May 2018.

Terry Whittaker / Men sorting seabird eggs, including those of Common guillemots (Uria aalge) into egg boxes, Skoruvikurbjarg cliffs, Langanes Peninsula, Iceland, May.

Terry Whittaker / Box of harvested seabird eggs, including those of Common guillemots (Uria aalge), Skoruvikurbjarg cliffs, Langanes Peninsula, Iceland, May.

Terry Whittaker / Man gathering harvested seabird eggs, including those of Common guillemots (Uria aalge) into a box, Skoruvikurbjarg cliffs, Langanes Peninsula, Iceland, May.

Nick Upton / Two Common swift eggs (Apus apus) in a nest box in a church belfry, inspected during a ringing study, Worlington, Suffolk, UK, July.

David Tipling / Eurasian pygmy owl (Glaucidium passerinum) eggs inside nest box, Finland, April.

LYNN M. STONE / Buff Wyandotte rooster perched on antique wooden egg case in grass beside rose bush. Calamus, Iowa, USA.