Data on timing of breeding, breeding success and diet of the European shag, sampled from the Isle of May population. The data were collected between 1985 and 2015 by visually checking nests and collecting regurgitated diet samples. These data are part of the Isle of May long-term study to assess population trends of seabirds under environmental change (IMLOTS https://www.ceh.ac.uk/our-science/projects/isle-may-long-term-study). Full details about this dataset can be found at https://doi.org/10.5285/6231bd5b-ee2d-4cca-a9ef-88006ffa4976

This dataset contains data on the movement of the seabird tick, Ixodes uriae, in an artificial arena. 24 adult female and 24 nymphal I. uriae were collected on the Isle of May, Scotland on the 25th-27th March 2014 and 18th July 2013 respectively. Nymphal ticks were taken from boiler suits worn by field workers, and adult female ticks were taken from cracks in the rock face. They were then transported to a laboratory where they were individually placed in an artificial arena, composed of a single A1 piece of paper and 30 cm high walls. Straight line distances moved were then measured at fixed time intervals. This work was part of a NERC-funded PhD project looking at interactions between avian colonial social structure and tick-borne pathogen dynamics. Full details about this nonGeographicDataset can be found at https://doi.org/10.5285/aec8b5b2-642b-41ae-8c30-36a4388411cb

This dataset contains plaque reduction neutralisation test (PRNT) results for common guillemot (Uria aalge) blood samples tested against twelve strains of a tick-borne virus, Great Island virus. 144 individual pre-breeding and breeding guillemots were captured between 1993 and 1995 on the Isle of May, Scotland and blood samples collected on filter paper. Plaque reduction neutralisation tests (PRNT) were then performed on these blood samples to detect virus strain-specific neutralising antibodies. Part of this dataset is presented in the peer-reviewed article Nunn et al. (2006) Parasitology 132: 233-40. This work was part of a NERC-funded PhD project looking at interactions between avian colonial social structure and tick-borne pathogen dynamics. Full details about this dataset can be found at https://doi.org/10.5285/bc1d9057-64b3-4b82-8db7-c5984d967659

This dataset contains activity data from thirteen common guillemots (Uria aalge) from the Isle of May during the 2005-2006 annual cycle. These biologging data were collected using global location sensing (GLS) time depth recorder (TDR) devices. From these data we derived daily data on guillemot activity budgets, sea surface temperature values, energy expenditure, location fixes and the proportion of dive activity that occurred during day, twilight and night. Data on colony attendance were also collected using daily time-lapse photography. Full details about this dataset can be found at https://doi.org/10.5285/bd24da1f-0761-4564-8dd8-dfd71a559a71

This dataset contains information on the parental behaviour, diet, condition and demography of common guillemots on the Isle of May, south-east Scotland. Annual data are available for 1982 to 2019 inclusive. These data are part of the Isle of May long-term study to assess population trends of seabirds under environmental change (IMLOTS https://www.ceh.ac.uk/our-science/projects/isle-may-long-term-study). Full details about this dataset can be found at https://doi.org/10.5285/f7676346-a67e-4fdf-9d30-e79ad2585195

This dataset contains prey items of common guillemot Uria aalge and razorbill Alca torda observed during the 2017 breeding season at East Caithness Special Protection Area, Buchan Ness to Collieston Coast Special Protection Area and Isle of May National Nature Reserve, off the east coast of Scotland. Full details are provided in the supporting documentation. Full details about this dataset can be found at https://doi.org/10.5285/62b58c5c-b733-426c-a6ea-61b3d9684b33

This dataset contains information on the breeding outcome, breeding site occupancy, and breeding site quality for a sample of common guillemots breeding on the Isle of May, Scotland. Data is available for all attributes from 1981-2018. These data are part of the Isle of May long-term study to assess population trends of seabirds under environmental change (IMLOTS https://www.ceh.ac.uk/our-science/projects/isle-may-long-term-study). Full details about this dataset can be found at https://doi.org/10.5285/33b42f0a-12a5-47fe-aaaf-25f4ee5e13a5

[THIS DATASET HAS BEEN WITHDRAWN]. This dataset contains calculated breeding success rates for six seabird species from representative colonies on the Isle of May, off the East coast of Scotland. Annual breeding success has been measured as the number of chicks fledged per active nest for the Atlantic puffin (Fratercula arctica, since 1982), common guillemot (Uria aalge, since 1982), razorbill (Alca torda, since 1982), European shag (Phalacrocorax aristotelis, since 1987), black-legged kittiwake (Rissa tridactyla, since 1987) and northern fulmar (Fulmarus glacialis, since 1987). The number of active nests recorded are also provided. Data were collected as part of the Isle of May long-term study (IMLOTS), which aims to identify the impact of environmental change on seabirds and their associated ecosystems. This monitoring has been ongoing since 1974, by essentially the same team of scientists, using the same well-documented methods throughout this time. Full details about this dataset can be found at https://doi.org/10.5285/02c98a4f-8e20-4c48-8167-1cd5044c4afe

This dataset contains data on the spatial attendance patterns of immature common guillemots (Uria aalge) at four sites in a large breeding colony. Data were collected from 25th April-12th May and 21st May-15th June 2013 at four sites on the Isle of May, Scotland. A grid was superimposed onto a photograph of each site. Grid cells were then classified as breeding or pre-breeding areas according to the presence or absence of breeding activity at any point during data collection (i.e. an egg or chick). A total of 69 randomly selected and individually-marked birds were followed using a telescope for 10 minute periods and their location in these grids was recorded every 15 seconds. This work was part of a NERC-funded PhD project looking at interactions between avian colonial social structure and tick-borne pathogen dynamics. Full details about this dataset can be found at https://doi.org/10.5285/dbd72bb5-4ad5-4d2f-b546-1cea672f76e8

[THIS DATASET HAS BEEN WITHDRAWN]. This dataset contains calculated return rates for five seabird species from representative colonies on the Isle of May, off the East coast of Scotland. Annual return rates are measured as the number of individually colour marked individuals seen in any one year that were also observed in the previous year for the Atlantic puffin (Fratercula arctica), common guillemot (Uria aalge), razorbill (Alca torda), European shag (Phalacrocorax aristotelis) and black-legged kittiwake (Rissa tridactyla). Not every individual is seen in any one year and the data set does not take into account those missed in any previous years hence these data are not to be treated as survival estimates. The Isle of May long-term study (IMLOTS) aims to identify the impact of environmental change on seabirds and their associated ecosystems. Understanding the mechanisms underlying variation in seabird population size requires a thorough knowledge of demographic parameters, namely birth rates, death rates, immigration and emigration. The effects of environmental change are likely to be different according to which demographic parameter or life history stage is being considered. This complexity means that only long-term monitoring, such as that carried out on the Isle of May, will allow us to understand the functioning of bird populations and their responses to environmental change. Full details about this dataset can be found at https://doi.org/10.5285/53251b3c-6c79-4aeb-a0de-fc63b9350cc1