The 500 pound World War Two device was picked up during dredging work.
Dog Walker Attacked In Bournemouth
Police in Bournemouth are appealing for witnesses and anyone with any information to come forward following a robbery on Charminster Road.
The incident, which happened sometime between 9pm and 11pm on Friday 27 April 2012, saw two men attack another whilst he walked his dog.
The offenders jumped out from shrubbery knocking the victim to the ground kicking and punching him, before making off with his keys, watch and a bank card.
The victim was left with facial bruising.
The only description he was able to give was that the two offenders were both wearing dark clothing.
Detective Constable Neil Montrose, of Bournemouth CID, said:
"This was a callous and brutal attack on a man whilst he walked his dog.
"We are very keen to hear from anybody who may have seen the attack take place, or saw anything suspicious around the time of the incident and leading up to it."
Witnesses and anyone with information should call Dorset Police in confidence on 101 quoting incident number 28;137. Alternatively, call the free and anonymous Crimestoppers line on 0800 555 111 where mobile phone tariffs may apply.
640 men were killed when the South African troop carrier was hit by a cargo ship in 1917.
The 79-year-old man suffered a serious head injury in the Cranmer Road car park in Winton.
Two Girls Indecently Assaulted Last Sunday
Recently Played Tracks
Deposit £10 to get a £40 Welcome Bonus - That's £50 to play bingo, slots and more!*
Over 50 tracks to make you feel-good. New album out now...
Find your local four day weather report here.
What's happening on the roads where you are?
Make Heart the soundtrack to your day and you could be a winner with great prizes up for grabs throughout the day.
Find out more about some of the companies advertising on Heart.
Get some great ideas on how to advertise your business on radio, online and on mobile.