The UK's Environment Agency (EA) says it is "highly likely" that the Pacific pink salmon will appear in rivers this summer.

The agency warns the appearance of the species could have an impact on native species, including the "threatened" Atlantic salmon.

While the Atlantic salmon are commonly farmed, and regarded as of "least concern" by the International Union for Conservation of Nature (IUCN), experts warn numbers have plummeted in recent years.

The Atlantic Salmon Trust says the marine survival of the wild salmon population has declined by 70% in just 25 years.

The Marine Conservation Society also urges people to avoid eating wild-caught Atlantic salmon - though classes some farmed Atlantic salmon as "best choice" in its Good Fish Guide.

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The decline in numbers has been put down to various pressures, including overfishing and the destruction of habitats.

The arrival of the invasive Pacific pink salmon to UK waters "is seen as an additional threat to their survival", according to the EA.

Sightings of the Pacific pink salmon - which have a distinct two-year life cycle - have previously been recorded in UK waters in 2019 and 2021 and experts believe they could return this year.

The fish - which originate from the northern Pacific Ocean - can be identified by large black oval spots on their tail, a very dark mouth and tongue and they have much smaller scales than the Atlantic salmon.

The EA has urged anglers to report catches or sightings of the invasive species.

Simon Toms, of the EA, said it teams were "working hard to contain and control invasive non-native species so that native fish, ecosystems and other wildlife are reduced from the damage they pose".

"That is why it is crucial that the public understand this immediate risk and report the capture or sightings of all pink salmon to us," he added.