Marie Read / Baltimore oriole (Icterus galbula) male perched in pear (Pyrus sp.) blossom, eastern redbud in background, New York, USA. May.

Claudio Contreras / Prickly pear (Opuntia sp.) growing on coastline, Socorro Island, Revillagigedo Archipelago National Park (Socorro Islands), Pacific Ocean, Western Mexico, November, Honorary Mention in the third natio...

Dietmar Nill / Close-up of two European hedgehogs (Erinaceus europaeus) feeding on windfall pears, Mossingen, Baden-Wurttemberg, Germany, October.

Jack Dykinga / Hairy bird's foot morning glory (Ipomoea leptotoma) flower over Prickly pair (Opuntia sp) Catalina State Park, near Tucson, Arizona, USA, August.

Floris van Breugel / Beavertail cactus (Opuntia basilaris) in otherwise stark desert, Alabama Hills, Owen's Valley, California, USA May

Marie Read / Baltimore oriole (Icterus galbula) male singing in spring, perched on Pear blossom (Pyrus sp.) flowers, New York, USA May.

Rolf Nussbaumer / Northern mockingbird (Mimus polyglottos) adult fighting with Golden-fronted Woodpecker (Melanerpes aurifrons) female over Texas Prickly Pear Cactus (Opuntia lindheimeri) Dinero, Lake Corpus Christi, S...

John Abbott / Giant prickly pear cactus (Opuntia echios var. gigantea) amongst carpetweed, Plazas Island, Galapagos

Rolf Nussbaumer / Golden-fronted Woodpecker (Melanerpes aurifrons), male perched on Texas Prickly Pear Cactus (Opuntia engelmanni). Laredo, Webb County, South Texas, USA, April.

Ernie Janes / Conference Pear tree (Pyrus communis) growing against wall in garden, UK

Floris van Breugel / Cholla cactus (Opuntia) backlit by setting sun, Anza Borrego State Park. California, USA. April 2009.

Suzi Eszterhas / Digger Bee (Melissodes sp) pollinating Engelmann Prickly Pear (Opuntia engelmannii) flower, Red Corral Ranch, Texas