ITS name is straight out of an adventure story - and it promises treasure for its new owners.
The RSPB has bought Hook Island with its wealth of wetland birds on the river Ouse, near Goole, for a knockdown £47,000.
Accessible only by boat, rarely visited by humans, the 19-acre land mass close to the village of Hook was originally put up for sale for £100,000 in 2009.
Pete Short, the RSPB’s Humber Sites manager, found out it was for sale again when he checked in at work over the Christmas holidays.
He said: “One of the staff had seen it was up for sale and sent me an e-mail saying: ‘Fancy this?
“I said it would make a good Christmas present and sent it up to my boss and he sent it to his boss at HQ in Bedfordshire and he said yes, let’s try and buy it.”
Before signing the deal Mr Short had his own Swallows and Amazon adventure when he set foot on the island with a boatman and ecologist. He said: “There are no footprints; when we were going round there were herons flying round us. It is somewhere special; somewhere away from people; a nice, little sanctuary.
“My assistant warden bird-watched it as a young land and he and his friend dreamed of having a den there, so it is actually a bit of a dream come true.”
Thousands of birds use the island; some like the lapwings and golden plovers feed on surrounding agricultural land before using the island to roost.
In spring, grey herons raise their chicks there. Little egrets – a rare type of heron – are sometimes seen and the RSPB hopes they may eventually form a breeding colony.