Experts from two marine charities are studying two unusual sightings off the Devon coast.
They believe at least one of them may be proof a sperm whale - first seen off Devon in June 2010 - may have returned.
The other sighting is of a creature with a "reptile-like" head which was seen off Saltern Cove on 27 July 2010.
Local man Dean Tapley described back in June how a routine fishing trip off Torbay turned into an "awesome" experience after he spotted a whale.
I've never seen anything like this
Now Trevor Smart, who is from Leicester, says he saw it on 21 July when he was heading out from Torquay Harbour towards Brixham to catch mackerel.
"I heard this whoosh behind me," he said. "I hadn't got a clue what it was."
"I turned around and about 18 to 22 metres away I could see what looked like a round dorsal fin - it was more of a rounded hump than the normal shape of shark's dorsal fin.
"There were three or four other smaller humps spread over a length of about the same as my dinghy.
"Then there was a little bow wave - which I now realise was the whale's head moving towards Brixham - about three to four metres ahead of the main hump.
"I just sat and watched it - I was totally enthralled.
"I have visited this area since the early 1960s and fished all my life, seeing dolphins and basking sharks and other sea life in our seas but I've never seen anything like this."
How to report a sperm whale sighting
Telephone 01545 561227
Once he returned to shore and talked to people in the harbour, he was told about the June sighting of a sperm whale.
He researched on the internet and realised that he too had seen a sperm whale and reported his sighting to Sea Watch, the marine conservation charity.
"It is very rare for a sperm whale to travel as far east as this in the Channel and to come so close to shore," said Sea Watch sightings officer Gemma Veneruso.
"Now that it has been seen again, we do have some concerns that it might strand.
"Sperm whales feed on deep sea squid and fish close to the edge of the continental shelf in the North Atlantic but rarely come into shallow waters although occasionally they have ventured into the western English Channel.
"The most distinguishing feature of the species is the huge square head. This can be one third to one quarter of the total body length of the sperm whale and they can be more than 18 metres in length.
"Another good way to recognise this species is the blow which has a forward and left direction, unlike other whales."
This picture was taken by Gill Pearce on 27 July 2010
Meanwhile Gill Pearce has reported seeing a reptile-like creature off Paignton to the Marine Conservation Society (MCS).
"Gill Pearce spotted the creature about 20 metres from the bay at Saltern Cove, near Goodrington," said Clare Fischer from the MCS.
"It was observed at about 15.30 on 27 July but by the time she had got her camera it had moved further out.
"She spotted it following a shoal of fish which beached themselves in Saltern Cove.
"The creature remained in the sea, then went out again and followed the shoal - this indicates it's not a turtle as they only eat jellyfish.
"We would love to know if other people have seen anything like this in the same area and can help clear up the mystery."
But are the most recent two sightings linked?
Clare thinks not.
"They [sperm whales] wouldn't come that close inshore and the reptilian-like head counts that out - at least that's what the experts are saying!"
So, have you seen any fishy off Torbay recently? Why not let us know by using the messageboard below.
-------------------------------------------------------------- Sperm whales have a single slit-like blowhole situated on the left side. Their blows are forward and leftward directed. At 0.08 into the video, it looked to me that the whale was blowing leftward. Sebastian, Vancouver, Canada
This video looked like two animals. A sperm whale and possibly a calf but more likely a different creature nearby. It could have been a Green sea turtle,loggerhead sea turtle,a seal-possibly even an out of place Medaterranean Monk seal or as happens in the United States a normally tropical/warm temperate mammal a manatee traveled far north of its normal range during the summer. The odd Florida manatees have travelled to New York-In this case if it is a manatee it would be the West African Manatee going beyond the normal range and into British waters. Dustin Munro, Ottawa, Canada
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