Breakfast at Billingsgate for Sammy the seal
29 March 2013 Last updated at 11:29 GMT
The UK's largest fish market, Billingsgate in London's Docklands, sells more than 100,000 kilos of fish each day.
More than 150 species of fish and shellfish from all over the world are sold at the market but a seal, nicknamed Sammy by porters, prefers to be fed salmon.
The BBC's Breakfast's Stephanie McGovern went to meet one of Billingsgate's most frequent customers.