Dataset Details - The First Atlas of Wintering Birds in Britain and Ireland: 1981/82-1983/84.
A dataset of the distribution and abundance of the wintering birds in Britain & Ireland from 1981 to 1984, generated using a list of the species observed and counts of individuals seen within each 10km square over the survey period.
The records were collected to compile as complete a wintering species list as possible for each 10-km square and provide a count of the number of each species seen. The dataset was used to produce the first BTO/IWC Wintering Birds Atlas (Lack P. (1986) The atlas of wintering birds in Britain and Ireland. T. & A.D. Poyser).
Specific fieldwork was conducted by mainly volunteer observers although professional help was used in some remoter areas.Two methods of fieldwork were requested from observers:1) Specific timed visits. An observer visited a 10-km square for a minimum of one hour and was asked to count all the individual birds seen in that time. At the end of the project these counts were standardized to a 'day' defined as 6 hours in the field by using a regression of numbers seen on time spent on a species specific basis.2) Supplementary Records. Observers were encouraged to send in any and all records of counts of species from 10-km squares. In particular these records were of species not seen on timed visits and those involving high numbers.The final published maps used the maximum count in a day over all three winters of each species divided into 3 levels such that 50% of positive records were placed in the lowest category (1), 30% in the middle category (2) and 20% in the highest category (3).
This datasets contains data only for the island of Ireland, but is part of the larger Britain and Ireland master dataset held by the British Trust for Ornithology at Thetford, U.K. All 10-km squares within the island of Ireland with more than a very small amount of land were visited.
Records for 10-km squares were collated over the three winters 1981/82, 1982/83 and 1983/84. The survey ran from the period 14, 13 and 12 November in each of the three winters respectively until the last day of February.
The maps as published are considered a true representation of the distribution and relative abundance of each species at a national level during the survey period. There will be some gaps in individual squares, especially for some of the more elusive and rarer species and some bias due to observer intensity.
The dataset available through Biodiversity Maps is for the island of Ireland but is only a subset of the larger British and Irish dataset held by the BTO. It was used to produce the first British Trust for Ornithology /Irish Wildbird Conservancy (now BirdWatch Ireland) winter bird atlas published as Lack, P. (1986) The Atlas of Wintering Birds in Britain and Ireland. T. & A.D. Poyser, Calton.
Full details of the methods used in the field, how fieldwork was organised and the interpretation of the maps is provided in the published atlas Lack, P. (1986) The Atlas of Wintering Birds in Britain and Ireland. T. & A.D. Poyser, Calton, or from the British Trust for Ornithology website at www.bto.org/birdatlas/previous/old_methods.htm. Specific queries as they relate to the Republic of Ireland should be made to BirdWatch Ireland at firstname.lastname@example.org
Open (Creative Commons CC-BY 4.0)
BirdWatch Ireland, The First Atlas of Wintering Birds in Britain and Ireland: 1981/82-1983/84., National Biodiversity Data Centre, Ireland, accessed 09 February 2023, <https://maps.biodiversityireland.ie/Dataset/21>
Dataset species distribution
Terrestrial Map - 10kmDistribution of the number of species recorded within each 10km grid square (ITM).
Marine Map - 50KmDistribution of the number of species recorded within each 50km grid square (WGS84).
Dataset record distribution
Terrestrial Map - 10kmDistribution of the number of records within each 10km grid square (ITM).
Marine Map - 50KmDistribution of the number of records within each 50km grid square (WGS84).
Records per year
Species per year
No Items available.
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