SWEEPING wildfires on Marsden Moor are threatening the survival of one of England’s rarest birds.

The fires, which were believed to have been started by arsonists, have destroyed one of the three remaining nesting sites for twites on the moor.

Firemen battled for several days in April to douse the blaze above Marsden. It burnt some eight square kilometres of land, which has been designated as a Site of Specific Scientific Interest.

Once the fire had been put out, it was discovered that one of the three twite colonies on the moor had been completely destroyed.

RSPB officers think it unlikely that the birds were killed as it was early for nesting. However, they fear that it is another setback for the embattled twite.

Peter Robertson, RSPB north of England regional director, said: “This could be a devastating setback for this bird.

“We have been working hard with farmers to help retain landscape features, like hay meadows, which are crucial to the bird. But inevitably England’s most threatened finch has been hit hard by these fires.

“We hope that the bird will have a future in England.”

The South Pennines around Huddersfield is home to some 100 breeding pairs – 85% of England’s vulnerable twite population.

The unique heathland landscape provides a vital habitat for these tiny brown finches. Over the last 14 years, England’s twite numbers have plummeted by 90%.

One of the main reasons is that the twite is one of only two birds which feeds only seeds to its young. The diet is not supplemented with insects or worms.

According to the RSPB, the twite is a barometer of the quality and extent of upland hay meadows and pastures. The future of the bird and these habitats are inextricably linked.

The dramatic decline in the twite population has resulted from the disappearance of many upland meadows, combined with modern agricultural practices.

Farmers around Huddersfield now generally take two crops of hay a year from upland meadows. One of these is usually in July, the middle of the twite breeding season. Wildflowers mixed in with the grasses are cut down before they have time to seed, so there is nothing for the bird to feed its fledglings.