Mark spends more than half a year travelling the world in search of wildlife and exploring wild places, so he is continually adding to his image collection. Use the new searchable database above to see what is currently available on line.
Take a browse, too, through Mark's recent photos to get an idea of what he has been up to lately – click on 'Pictures of the Month' above the image. For advice, meanwhile, on many fields of photography as written by Mark and published in BBC Wildlife magazine, go to 'BBC Wildlife Photo Masterclass', also above the walrus photo.
Mark has been Chairman of the judging panel of the prestigious Wildlife Photographer of the Year Competition since 2005.
He will soon begin working on Wild Wonders of Europe, a massive photographic project involving Europe's 50 top wildlife photographers.