Jeffrey Lendrum, 48, was caught at Birmingham International Airport with 14 rare peregrine falcon eggs hidden in socks strapped to his body.
Lendrum, who according to reports is an Irish citizen, was headed for Dubai where falconry is a widely popular sport and where his loot could have fetched him as much as 70 000 pounds or about US$100 000 on the black market
He was arrested after a cleaner spotted him behaving suspiciously and tipped off airport security.
Lendrum, who investigators described as the highest level of wildlife criminal, at first told the police that he had bought the eggs from a shop and claimed he needed them to treat his sore back.
But he pleaded guilty last Thursday at Warwick Crown Court in western England, looking visibly embarrassed as he stood with his arms crossed and his head bowed for nearly the entire hearing.
Lendrum, who officers said was carrying thousands of pounds when they arrested him, admitted to one count of trying to export the eggs and another of illegally stealing them from a nest on the side of a mountain in Rhondda.
Committing Lendrum to prison, Judge Christopher Hodson said the former soldiers crime hurt not only the local area "but in some measure to the planet and its future".
Prized in falconry for their phenomenal speed -- they are thought to reach up to 200 miles (320 kilometers) per hour when they dive -- the birds are a protected species under British law, which bars their export.
Lendrum had previous convictions in Zimbabwe and Canada for stealing rare eggs. He once abseiled off a cliff to reach a nest, while on another occasion he lowered himself from a helicopter in Canada to reach his prize.