Heartbreaking footage shows a swan refusing to leave the side of its dead partner as fears grow over the spread of bird flu across Kent.

The distressing video was filmed at Minster Marshes in Thanet, where several of the birds – known to form pair bonds for life – have died in recent months.

It was captured by Johnny Allen from Kent Wildlife Rescue, who said witnessing the scene “broke” him.

He told KentOnline the female swan had been seen just months earlier with eight cygnets in tow, which are now unaccounted for.

Mr Allen says more than 50 swans have been found dead across the Canterbury and Thanet areas – including along the Sarre Penn and River Wantsum.

While bird flu is a growing concern, those on the ground rescuing and treating the birds believe a pollution incident that killed thousands of fish in November may also be contributing to the deaths of mute swans.

Dead swans began appearing at the same time and in similar locations to the fish deaths, and rescuers say the protected species feeds along riverbeds, potentially exposing them to contaminants.

Johnny Allen says seeing the swan next to its mate in Thanet "broke" him. Picture: Johnny AllenJohnny Allen says seeing the swan next to its mate in Thanet “broke” him. Picture: Johnny Allen

They also say some birds have responded positively to treatment for suspected poisoning, including the use of charcoal.

However, the Environment Agency has played down suggestions of a link.

When asked about the claims by KentOnline, a spokesperson said the organisation is “not aware of any connection between the dead swans and fish”.

Mr Allen has been at the frontline of efforts to help the birds.

“I have been working tirelessly for the last two months, recovering both dead and sick swans,” the 65-year-old said.

He claims only one swan has clearly displayed bird flu symptoms, adding that vets identified others as suffering from “toxic poisoning”.

One of the dead swans found in the Sarre Penn, between Canterbury and Thanet. Picture: Johnny AllenOne of the dead swans found in the Sarre Penn, between Canterbury and Thanet. Picture: Johnny Allen

“The main difference between avian influenza symptoms and those of poisoning is that with poisoning, there is no chest rattle or discharge from the nostrils, mouth and eyes,” he said.

The Environment Agency confirmed an investigation into the source of the pollution is ongoing, but said the pollutant is no longer present in the water.

“Increased flows in the watercourse allowed further dilution and natural breakdown of the pollutant,” they added.

“There have been no further signs of wildlife in distress. We are not aware of any connection between the dead swans and fish.

Previously, Mr Allen told KentOnline he feared the swan population in Thanet would be “decimated” this winter.

Johnny Allen is a volunteer for Kent Wildlife Rescue Service. Picture: Johnny AllenJohnny Allen is a volunteer for Kent Wildlife Rescue Service. Picture: Johnny Allen

Confirmed cases of avian influenza in wild birds have continued to rise across Kent.

In the week commencing November 17, a mute swan and a herring gull were confirmed to have the disease in the Canterbury district, along with one swan in Thanet and one in Swale.

The following week, it was found in a dead herring gull in Thanet and another two mute swans in Canterbury.

In the week commencing December 8, one case was confirmed in a swan in Folkestone.

The Animal and Plant Health Agency (APHA), which oversees avian influenza, will collect only five carcasses from a given species to test for the virus in any one area.

One swan was rescued from a water works in Sandwich. Picture: Johnny AllenOne swan was rescued from a water works in Sandwich. Picture: Johnny Allen

The responsibility for removing remaining animals – which would otherwise be left to rot or be scavenged – falls to volunteers such as Mr Allen.

One of the rescued swans was found on a path near a water treatment centre in Sandwich.

Mr Allen said: “It is just one of many currently in care. They will be fed, cleaned, and receive treatment in a warm, safe environment.

“This costs money, and despite what we thought when we were young, money doesn’t grow on trees.”

A pollution incident killed thousands of fish in the Sarre Penn and River Wantsum. Picture: Johnny AllenA pollution incident killed thousands of fish in the Sarre Penn and River Wantsum. Picture: Johnny Allen

A national report published by the APHA on December 19 said bird flu cases have been particularly high among mute swans.

“Through December, wild bird cases have continued mainly in resident geese, swans and ducks,” it said.

The wild bird risk level across the UK remains ‘very high’.

Elsewhere in Kent, more than 60 birds were culled after testing positive for avian influenza at the Happy Pants Ranch animal sanctuary in Newington, near Sittingbourne.

Outbreaks have also been confirmed at two nearby poultry farms, as well as another in Lydd.

The swan in Thanet next to its dead mate. Picture: Johnny AllenThe swan in Thanet next to its dead mate. Picture: Johnny Allen

The UK Health Security Agency says the risk to the general public from bird flu remains very low.