Biodiversity

Graph of the Day: Decline of U.K. wildlife, 1968-2010

Desdemona Despair,

29 July, 2013

Watchlist Indicator showing the average population trend for 77 moths, 19 butterflies, 8 mammals and 51 birds listed as UK BAP priorities, 1968-2010. Species are weighted equally. The indicator starts at 100; a rise to 200 would show that, on average, the populations of indicator species have doubled, whereas if it dropped to 50 they would have halved. Dotted lines show the 95% confidence limits. Graphic: RSPB

22 May 2013 (RSPB) – Between 1995 and 1999, 577 species were identified as priorities for conservation in the UK under the UK Biodiversity Action Plan (BAP). The list was reviewed in 2007, and doubled in length to 1,150 species. Since then, national biodiversity strategies have been developed so that each of the UK’s four nations now have their own list of priority species.

We have developed a new Watchlist Indicator, showing the overall trends in populations of 155 species that were listed as UK BAP priorities, and present it here for the first time. Lack of comparable data meant that we were unable to include trends for any species of plants or fungi, despite these making up 48% of the UK BAP list, nor any invertebrates other than butterflies and moths.

Since 1970, the indicator has dropped by 77%, representing a massive decline in the abundance of priority species. There was a steep decline in the early years of the indicator, but this is to be expected because it was these declines that led many species to be included in priority lists in the first place. What is important is whether the decline has stopped in response to conservation action: worryingly, it has not. The indicator declined by 18% between 2000 and 2010, suggesting ongoing declines in priority species. It may now be stabilising, but more years of data are needed to confirm this.

As with all composite indicators, the Watchlist Indicator hides considerable variation in individual species. Some priority species, such as the bittern and Adonis blue butterfly, have shown substantial recoveries since they were added to the first priority species list in 1995 thanks to creative and concerted conservation efforts. However, many species are showing continuing, and in some cases severe, or even accelerating, declines.