Since 1986, seabird populations in the UK and Ireland have been monitored through the Seabird Monitoring Programme coordinated on behalf of partnership organisations by JNCC. Sample data on breeding abundance and breeding success of seabirds are collected from a large network of sites, both regionally and nationally, to enable species’ conservation status to be assessed. To examine trends at individual colonies, at country level and across the whole UK, it is essential that individual sites can be monitored consistently for many years. Data on breeding abundance – the number of breeding pairs or individuals – provide a medium to long term measure of how populations are faring. Data on breeding success/productivity – the number of chicks fledged per breeding pair – are regarded as short term or more immediate measure of population status. Studies at four key sites (Isle of May, Canna, Fair Isle and Skomer) provide information on adult survival, diet, phenology used to help to diagnose the changes in abundance. Additional information on survival rates at other sites is collected through the BTO’s Retrapping for Adult Survival (RAS) scheme (Horswill et al. 2016), although there are no current RAS sites in Northern Ireland. The SMP generates annual indices of abundance and breeding success from these data which are expressed as a percentage of the population recorded at sites in 1986 when standardised monitoring began (JNCC 2016). Where possible trends are given at the scale of the UK or country level, but where coverage is only possible at individual sites, the indices are shown at the site level. The SMP is a vital programme for monitoring seabird population trends between the full national censuses.

As demand for food increases, a crucial question in conservation is how to limit the negative impacts of agriculture on biodiversity. ‘Land sparing’ has been proposed as a strategy to address this problem, with high-yield agriculture minimising the area of farmland so that other land can be spared for conservation. Research – mostly from tropical regions – suggests that most species would achieve larger populations under a land-sparing strategy than under a strategy in which lower-yielding wildlife-friendly farmland delivers food production over a larger total area. It has been argued, however, that wildlife-friendly farming might be more appropriate away from tropical deforestation ‘frontiers’. In the UK, for example, some species which depend on large areas of unmodified habitat have been lost. Instead, conservationists here are particularly concerned about declining farmland wildlife, which are probably unlikely to benefit from a land sparing strategy. An additional question relates to food demand: what might be the biodiversity consequences of reducing food waste, or making more efficient use of land by consuming fewer animal-derived foods? In a new study published in the Journal of Applied Ecology, scientists from the University of Cambridge, RSPB and BTO estimated UK food demand in 2050 under three scenarios: ‘waste’ (50% reduction in avoidable post-harvest waste), ‘diet’ (50% reduction in animal product consumption) and ‘reference’ (no change in waste or diet). They then designed contrasting land-use strategies which met these levels of demand by either maintaining the UK’s current farmed area and increasing yields just enough to meet demand (‘no-sparing’), or by increasing yields in line with technical upper-bounds, allowing the farmed area to shrink and the area of woodland and wetland habitat to grow. They then estimated the change in population size of 156 breeding bird species data from the Breeding Bird Survey. The study found that, on average, bird populations would decline under the no-sparing scenario but would increase under the sparing scenario. In other words, the benefits to bird populations of large-scale habitat restoration outweigh the costs of higher yields on farmland. Not all species showed the same pattern though: unsurprisingly, woodland and wetland birds did much better under the sparing strategy, whereas farmland birds did much worse. So, the overall benefits of land sparing should be considered in the context of this trade-off. Reducing food demand through changing diets or cutting food waste resulted in more positive bird population trends, but the sparing strategy still outperformed no-sparing when averaged across all species. The study raises questions about land-use policies in the UK and elsewhere, where current agri-environment policies tend to favour wildlife-friendly farming approaches. Land-sparing policies are not without challenge though, and the authors highlight two important caveats. First, land sparing is unlikely to occur without policies which explicitly link yield-growth in one place to habitat restoration in another. Second, the high-yields associated with land sparing must be sustainable in the long-term and minimise the degradation of natural capital such as soil and freshwater.