• Declining species

• New alerts

• Positive changes

• Reduced breeding success

• Increased breeding success

• Early breeding

Declining species

Best trend estimates over the longest available time period (usually 39 years) provide alerts to population declines of greater than 50% for 22 species.

These are Grey Partridge, Little Grebe, Woodcock, Turtle Dove, Cuckoo, Lesser Spotted Woodpecker, Skylark, Tree Pipit, Yellow Wagtail, Song Thrush, Whitethroat, Willow Warbler, Spotted Flycatcher, Willow Tit, Marsh Tit, Starling, House Sparrow, Tree Sparrow, Linnet, Lesser Redpoll, Yellowhammer and Corn Bunting. In addition, Lapwing has declined by 53% in the last 25 years, although its 39-year decline is measured at 34%.

The Whitethroat decline results from the severe crash between 1968 and 1969 linked to conditions on the wintering grounds. The Little Grebe decline should be treated with caution as we have long-term data from only a subset of its breeding habitats. Apart from these two, all these rapidly declining species are already red or amber listed on the Population Status of Birds (PSoB) list (Gregory et al. 2002).

For several of the species listed here long-term trend data are only available for England, where BTO has more volunteers to record information. Different long-term trends could be operating in other parts of the UK. Lesser Redpoll, Tree Pipit and Woodcock, in particular, have limited data.

A further ten species trigger alerts as a result of long-term declines of between 25% and 50% over periods of 22 to 39 years. These are Common Sandpiper, Redshank, Little Owl, Meadow Pipit, Dunnock, Mistle Thrush, Sedge Warbler, Reed Warbler, Lesser Whitethroat and Bullfinch. Most of these species are already on the PSoB list on account of their population declines.

Recent alerts and alert changes

We draw special attention to the alerts for four species that have recently crossed the 50% decline threshold in the 25-year period. These are Yellow Wagtail (-70%), Cuckoo (-61%), Willow Warbler (-58%), and Lapwing (-53%). These species, all currently amber listed, may be candidates for addition to the red list at the next PSoB revision. Lapwing is an addition to this set of species this year; no species has fallen out.

We also identify three species that may be candidates to join the amber list (from green) owing to declines of between 25% and 50%. These are Common Sandpiper (-28% over 25 years), Sedge Warbler (-33% over 22 years) and Lesser Whitethroat (-59% over 22 years). Sedge Warbler is an addition to this set of species this year; one species, Tawny Owl, has fallen out because its decline no longer meets alert thresholds. Little Owl has also decreased strongly (-46% over 25 years) but is not eligible for amber listing because it is not native to the UK.

The alerts for Sedge Warbler and Lesser Whitethroat are raised by CES data, with census results showing shallower, non-significant declines. In addition, a CES decline of 33% in Reed Warbler may warrant investigation, although CBC, BBS and WBS results indicate that the species has increased.

Bullfinch is a currently red-listed species, but its long-term population decline is now marginally under the red-list threshold, at -50% over 39 years, due to a population increase of 7% over the past five years. Unless the decrease resumes, this species may be a candidate for changing from the red to the amber list. Similarly the red-listed Reed Bunting now shows only a 19% decline over the last 39 years, with a significant upturn recorded over the past ten years. It is now questionable whether conservation listing is still warranted for this species.

Three currently amber-listed species, Kestrel, Grey Wagtail and Goldcrest, would no longer meet the population change criterion for amber listing, although Kestrel is also amber listed for reasons to do with its European status.

Positive changes

Only a few of those species that have declined previously show evidence of improvements in status, with eight formerly declining species showing clear positive trends over the last ten years. These are Snipe, Grey Wagtail, Dunnock, Song Thrush, Whitethroat, Goldcrest, Tree Sparrow and Reed Bunting.

The increases in the red-listed Reed Bunting and Song Thrush are particularly encouraging, as are the positive trends for the amber-listed Grey Wagtail and Dunnock. However, the most recent figures for Song Thrush and Grey Wagtail suggest that their recoveries may be levelling off well short of their previous population levels. Similarly while the BBS shows a 29% increase in Snipe over the last ten years, much of the former range across lowland Britain lost since the 1960s remains unoccupied, and moreover the population has been declining again since 2003.

Seventeen species have more than doubled over the longest time period for which data are available (usually 39 years). These are Mute Swan, Shelduck, Mallard, Goosander, Oystercatcher, Sparrowhawk, Buzzard, Stock Dove, Collared Dove, Woodpigeon, Green Woodpecker, Great Spotted Woodpecker, Nuthatch, Blackcap, Great Tit, Magpie and Carrion Crow. Canada Goose has been lost to this group since the last report, WBS counts having levelled off, but BBS data indicate a continuing strong increase.