Tests are under way to establish whether the creatures live permanently in Wales' waters.
Read moreBBC News Science & Environment

Capsule with asteroid samples in 'perfect' shape
A team retrieves a capsule carrying the first significant quantities of rock from an asteroid.
Top Stories

Capsule with asteroid samples in 'perfect' shape
A team retrieves a capsule carrying the first significant quantities of rock from an asteroid.

Thames tunnel 'will create 5m tonnes of CO2'
Campaigners accuse Boris Johnson of mocking his own promises on climate change and emissions.

RAF cameras capture world's biggest iceberg
A reconnaissance flight in the South Atlantic obtains spectacular imagery of the giant iceberg A68a.

Hens in Britain to be kept indoors due to bird flu
The virus - said to be "low risk" to humans - has been identified at sites across Great Britain.

UK's 68% climate change target a 'huge challenge'
The "ambitious" target for 2030 would see the UK move faster than any major economy, the PM says.

China's Chang'e-5 mission leaves Moon's surface
The robotic probe lifts off from the lunar surface carrying samples of rock and dust to send to Earth.

Nasa to pay company $1 to collect rocks from moon
The US space agency has awarded two American and one Japanese firm contracts to pick up lunar soil.
Featured Contents

Capsule with asteroid samples in 'perfect' shape
A team retrieves a capsule carrying the first significant quantities of rock from an asteroid.

Thames tunnel 'will create 5m tonnes of CO2'
Campaigners accuse Boris Johnson of mocking his own promises on climate change and emissions.

RAF cameras capture world's biggest iceberg
A reconnaissance flight in the South Atlantic obtains spectacular imagery of the giant iceberg A68a.

Hens in Britain to be kept indoors due to bird flu
The virus - said to be "low risk" to humans - has been identified at sites across Great Britain.

UK's 68% climate change target a 'huge challenge'
The "ambitious" target for 2030 would see the UK move faster than any major economy, the PM says.

China's Chang'e-5 mission leaves Moon's surface
The robotic probe lifts off from the lunar surface carrying samples of rock and dust to send to Earth.

Nasa to pay company $1 to collect rocks from moon
The US space agency has awarded two American and one Japanese firm contracts to pick up lunar soil.

Thames tunnel 'will create 5m tonnes of CO2'
Campaigners accuse Boris Johnson of mocking his own promises on climate change and emissions.

RAF cameras capture world's biggest iceberg
A reconnaissance flight in the South Atlantic obtains spectacular imagery of the giant iceberg A68a.

Hens in Britain to be kept indoors due to bird flu
The virus - said to be "low risk" to humans - has been identified at sites across Great Britain.
Space
Latest Updates
By Paul Rincon
Science editor, BBC News website
By Judith Burns
BBC News
By Alex Pope
BBC News Online
By Paul Rincon
Science editor, BBC News website
Video content
Video caption: Divers to clear 1,000 tyres from Plymouth Sound Archaeologists have predicted there could be 1,000 tyres on the seabed of Plymouth's harbour.

By Jonathan Amos
BBC Science Correspondent
Video content
Video caption: Fighting air pollution: 'Without solidarity the world will be doomed' Nineteen-year-old Abhiir Bhalla has campaigned against air pollution in Delhi most of his life.
Death by DNA
Video content
Video caption: Could a rogue scientist or a terrorist assemble a lethal pathogen from mail order genes? Has DNA technology advanced so far that a rogue scientist, or even a competent terrorist, could assemble a deadly pathogen from genetic sequences bought by mail order?
Video content
Video caption: What is thunder snow? Parts of Scotland experienced a rare meteorological phenomenon early on Friday morning - thunder snow. Nick Miller explains what it is.
Video content
Video caption: Thunder snow - what is it? Residents of Scotland were woken up last night by a strange sound which some thought was an explosion. It turned out to be thunder snow, an uncommon meteorological phenomenon.



































