London: The UK has lost more than 44 million breeding birds in less than half a century, including an average of 50 house sparrows every hour, according to a report.

Scientists estimate the number of nesting birds has plummeted from 210 million in 1966 to 166 million today. The shocking statistics are contained in the State of the UK’s Birds 2012 report, published on Monday, and charting the ups and downs of the nation’s bird populations.

One of the biggest losers is the house sparrow, with a population of around 10 million — 20 million fewer than in 1966, when the first reliable all-species bird monitoring scheme was conducted — despite numbers starting to increase in the last 10 years.

There has been a steep decline in willow tits, especially since the 1990s, with the species all but disappearing from most of the UK, and only the Midlands and Yorkshire boasting sizeable populations. Lesser spotted woodpeckers are now too few to monitor properly, as are arctic skuas. The report estimates there could be as few as 1,500 pairs each of the three species left in the UK.

The populations of farmland bird species is now less than half what it was in 1970, according to the report, which draws on data from leading organisations including the RSPB, the British Trust for Ornithology (BTO), the Wildfowl and Wetlands Trust (WWT) and Birdlife International, as well as government agencies.

Experts say breeding birds have vanished from the British countryside at an average rate of one pair every minute.

Changes in land use and management of the coastal waters are believed to have contributed to the losses. In some cases, birds have found it difficult to locate suitable places to nest, or to forage for food in the summer or winter.

Cold weather has impacted, too, and is believed to have had a startling effect on the wren. Still the UK’s most numerous bird, an average of 835 wrens have been lost each day since 2000. The reasons behind the house sparrow decline are still not fully understood.

Two of the UK’s seaducks — the velvet scoter and the long-tailed duck — are now considered threatened with extinction globally.

However, bitterns, corncrakes and nightjars have shown steady recovery in numbers, thought to be due to conservation measures to protect them.

There have been winners as well as losers. The chaffinch has increased at a rate of 150 individuals a day over the period.

The collared dove, whose numbers were very low as the species only started nesting in the UK in 1955, has seen its numbers explode to around 1 million pairs.

The closely related turtle dove, which in 1966 was widespread with around 140,000 breeding pairs, however, has been decimated. Today there are thought to be just 14,000 nesting pairs.

The report, which also examined bird populations of the UK’s overseas territories, highlighted concern over the northern rockhopper penguin, found on the remote south Atlantic volcanic islands of Tristan da Cunha and Gough Island. Once to be found in their millions, the numbers of the distinctive penguins have crashed, with food resources, disease and predation all being possible causes.

Mark Eaton, an RSPB scientist, said of the report: “It is shocking to think we’ve lost one in five of the individual birds that we had in the 1960s, especially when you think that the 44 million birds we have lost since 1966 is equivalent to the current adult human population of England and Wales.”

Richard Hearn, from the WWT, said: “Sea duck numbers in Europe have crashed and they urgently need conservation.

“Velvet scoter overwintering in the UK have gone from several thousand birds to less than 100 in just a few years, and the picture for the long-tailed duck is similar. Several other species have also shown large declines.

“By tying our findings with similar reports from the Baltic and elsewhere, we’re getting a clearer understanding of the problem, but to be effective we need all countries to work more closely together.”