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Saltmarshes are areas of coastal grassland that are regularly flooded by seawater. They support a large number of resident and migratory bird species, both overwintering and breeding. The Mersey Estuary Site of Special Scientific Interest (SSSI) is situated in North West England and it supports nationally significant numbers of overwintering wildfowl and waders. Decline of three overwintering bird species’ populations (pintail, teal and wigeon) were more marked than national trends, so changes in local factors were believed to play a part. The aim of this study was to determine whether habitat suitability for the three target species changed between 2002 and 2012 in saltmarshes on the Mersey estuary. One habitat suitability model per species was built using a variety of source data (elevation, vegetation and macroinvertebrate surveys, aerial photography, questionnaires) and expert judgment to evaluate the relative importance of factors. Models uncertainty was estimated using “bounding maps” representing the most extreme plausible scenarios for each factor contributing more than 10% to the total value of the habitat suitability index. Saltmarsh area decreased between 2002 and 2012 in the Mersey Estuary, reducing available habitat for all three target species. Vast areas of pioneer zone disappeared during the study period, especially affecting species like pintail, which preferentially feed on pioneer zone species. Evidence suggested that although recreational disturbance is likely to be an issue in parts of the study area, its intensity did not change notably during the study period. Wildfowling, however, significantly affected the suitability of the study site for all species. The western part of the site had no shooting disturbance in 2002 but by 2012 a clay-pigeon shooting club had opened nearby. Although this activity does not cause direct damage to birds, the shooting noise is likely to make birds avoid the area. In addition, wigeon was also negatively affected, Saltmarshes are areas of coastal grassland that are regularly flooded by seawater. They support many bird species, which spend their winters there or breed in the summer. The Mersey Estuary Site of Special Scientific Interest (SSSI), in the North West of England, supports overwintering bird populations of national importance. Numbers of three of these species (pintail, teal and wigeon) have been decreasing in the Mersey estuary more than we would expect looking at how the population is doing at the national level. Thus, local factors are likely to play a part. This study tried to see if habitat suitability for these species changed between 2002 and 2012 in saltmarshes on the Mersey estuary. One habitat suitability model per species was built using many different datasets (elevation, vegetation and macroinvertebrate surveys, aerial photography, questionnaires) and expert judgment to select which factors were important and what their relative importance was. Models uncertainty was estimated looking at the variability between habitat suitability values obtained according to different modeller’s decisions. Saltmarsh area decreased between 2002 and 2012 in the Mersey Estuary, reducing available habitat for all three bird species. The pioneer zone was especially affected by erosion and pintail, which prefers feeding on pioneer zone plants, suffered negative effects. Although recreational disturbance is likely to be an issue in parts of the study area, its intensity did not change between 2002 and 2012. Wildfowling, however, made the site less suitable for all species. There was no shooting in the western part of the site in 2002, but by 2012 a clay-pigeon shooting club had opened nearby. This activity does not cause direct damage to birds, but the shooting noise is likely to disturb them. In addition, wigeon was also negatively affected by increased numbers of Canada goose, an invasive bird species, in the eastern part of the study site. The decrease in numbers of pintail

It has long since been noted that minor element (Me) partitioning into biogenic carbonates is sometimes different from Me partitioning into inorganically precipitated carbonates. The prime example is the partitioning coefficient, which might be lower or even higher than the one of inorganically precipitated carbonate. Such a difference is usually termed “vital effect” and is seen as indicative of a biologically modified minor element partitioning. Over the last three decades interest in conceptual biomineralization models compatible with minor element and isotope fractionation has been steadily increasing. However, inferring features of a biomineralization mechanism from Me partitioning is complicated, because not all partitioning coefficients show vital effects in every calcium carbonate producing organism. Moreover, the partitioning coefficient is not the only aspect of Me partitioning. Other aspects include polymorph specificity and rate dependence. Patellogastropod limpets are ideally suited for analysing Me partitioning in terms of biomineralization models, because they feature both aragonitic and calcitic shell parts, so that polymorph specificity can be tested. In this study, polymorph-specific partitioning of the minor elements Mg, Li, B, Sr, and U into shells of the patellogastropod limpet Patella caerulea from within and outside a CO2 vent site at Ischia (Italy) was investigated by means of LA-ICP-MS. The partitioning coefficients of U, B, Mg, and Sr (in aragonite) differed from the respective inorganic ones, while the partitioning coefficients of Li and Sr (in calcite) fell within the range of published values for inorganically precipitated carbonates. Polymorph specificity of Me partitioning was explicable in terms of inorganic precipitation in the case of Sr and Mg, but not Li and B. Seawater carbon chemistry did not have the effect on B partitioning that was expected on the basis of data on inorganic precipitates and foraminifera. Carbon chemistry did