The official results for the Wild Bird Indicators have been released by Government today. Here, Mark Eaton, Principal Conservation Scientist, gives a breakdown on the results and what this means for conservation

The new Wild Bird Indicators for the UK were published by Defra this morning, and can be found online here. Similar metrics have also been released for England, and can be found here. These indicators are official Government statistics, part of a suite of measures on the state of biodiversity, and the pressures upon it and the action taken to help it.

These UK Biodiversity Indicators are published in a valuable compilation every year – most recently in October 2020, here – but given the prominence of the wild bird indicators they get these separate releases as well. Today’s update brings the measures up to 2019, with data in some cases starting from 1970 – measuring nearly 50 years of change in the UK’s birds.

These measures have been part of my working life for the two decades I’ve been with the RSPB. Working in partnership with the British Trust for Ornithology, who do the hard work, crunching the numbers collected by thousands of volunteer surveyors, and funded by Defra, every year we collate the trends in common and widespread breeding birds (any species with more than 500 breeding pairs in the UK) and use these to calculate average trends across species. Species are grouped, to give measures of change in major habitats: farmland, woodland, water & wetland, seabirds, and wintering waterbirds. In addition, an ‘all-species’ line is produced to give an overview and ‘mop up’ a number of generalist species that don’t fall into these habitat categories.

Fortunes of farmland birds

As a consequence of working on these indicators for so many years, alongside reporting on the UK’s wildlife in other indicators, red-lists and “state-of” reports, I have probably become somewhat numb to the grim news they carry, but for those less familiar with them they must come as a shock. My first contract for the RSPB, in 2001, involved looking at the 19 species included in the farmland bird indicator and how their fortunes could be turned around and the indicator reversed… little did I imagine that 19 years later not only have we failed to reverse the decline in the indicator, but that it has continued downwards.

Turtle dove, one of the species which has continued to decline (c) Ben Andrew (rspb-images.com)

The farmland bird indicator is undoubtedly the one that has received the most attention over the years, and has proved a powerful measure of the losses of farmland birds, and the declines in other wildlife which we know have accompanied this, since the 1970s. On average farmland bird populations have declined by 57% since 1970; the greatest period of loss was during the late 1970’s and early 1980’s, a period which saw rapid changes in agricultural management, driven by the agricultural policies of the day, which had far-reaching consequences upon wildlife.

In recent years the decline in the farmland bird indicator has been slower, and no doubt the actions of a great many farmers to help wildlife, supported by government-funded agri-environment schemes, have played an important part in slowing the decline.

However, the scale of this response has remained insufficient to stem the loss, let alone to reverse it, and the indicator has fallen by 5% over the last five years for which change is measured (2013 to 2018 – although the indicator runs to 2019, change is measured using a smoothed measure, better for revealing underlying trends, which runs up to 2018). Five of the species in the indicator – grey partridge, turtle dove, starling, tree sparrow and corn bunting – have fallen to less than 20% of their 1970 numbers.

Other habitats also show a grim picture

News from other habitats is, I’m afraid, not much cheerier. The woodland bird indicator has fallen by 27% since 1970, and by 7% in the last five years. All indicators present a simple message from complicated information, and the overall decrease in the indicator does hide good news on a range of woodland birds that have increased with, for example, blackcap, nuthatch and great spotted woodpecker all having doubled or more.

But steep declines in both resident woodland specialists such as lesser spotted woodpecker and willow tit, and sub-Saharan migrants including spotted flycatcher and wood warbler, have driven the overall decline in the indicator.

Spotted flycatcher numbers have dropped 88% since 1970 (c) Ben Andrew (rspb-images.com)

The indicator for breeding birds of water & wetlands has fallen by 12% since its 1975 starting point, although has been relatively stable (a 1% increase, in fact) over the last five years. If we delve deeper, and look at trends in birds of different wetland habitats, we can see there are marked differences.

Species of slow moving and standing water have increased by 33%, with the likes of tufted duck and mallard increasing, whereas the line for birds of wet grassland has dropped to 48% of its starting point owing to steep declines in breeding waders – snipe, redshank and lapwing.

The UK has internationally important populations of seabirds, so the decline in the seabird indicator, now 28% below its 1986 start point, is of great concern although it has increased by 3% over the last five years. This indicator is created from trends in 13 species that are monitored annually by the Seabird Monitoring Programme, and so is missing data for a further 12 species for which we require periodic whole-UK censuses for status updates. The most recent of these censuses, Seabirds Count, is due to be completed in 2021 and report results in 2022, which will then give us a better understanding of how our seabirds are faring.

Herring gull have decline by 51% since 1986 (c) Ben Hall (rspb-images.com)

Some good news for waterbirds

Finally, some good news, in that the indicator for wintering waterbirds remains 88% above its 1975/76 starting value. Populations of most of the wintering wildfowl and wader species that winter on the UK’s lakes, wetlands, estuaries and coast, many in vast numbers, rose steadily from the 1970s to a peak in the late 1990s.

Since then, however, there has been a slow but steady decline over the last two decades. Over the last five years the indicator has fallen by 3%. There’s good evidence to how milder winters have led to range shifts in wintering waterbirds, leading to fewer birds migrating to the UK – but in some cases, such as for Bewick’s swans and pochards, there have been population-wide declines.

A hopeful future

Great spotted woodpecker has more than trebled in numbers (c) Louise Greenhorn (rspb-images.com)

So, apologies if you have found my summary above, and the full reports for both the UK and England indicators, depressing reading. There is plenty of good news to be found on the UK’s birds elsewhere on the RSPB’s website, as the work of the RSPB, other conservation organisations, governments, landowners, farmers and private individuals has resulted in inspiring conservation recoveries for sites, habitats and threatened species such as bitterns, cirl buntings and red kites.

But across the wider countryside, outside of reserves, protected areas, and targeted conservation projects, we still need more sustainable land management, integrating our need for products such as food and timber while safeguarding resources such as clean water and healthy soils, and giving space to nature, to allow birds and other wildlife to recover.

One day, I hope to write this blog bringing news of increasing indicators heralding a recovery in our wildlife!

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