National Urban Gull Survey: 23rd April – 7th May
As the final part of the National Seabirds Count Survey, fieldwork in 2019 will focus on a survey of urban-nesting gulls. It’s impossible to completely count every breeding bird in such a difficult environment, so the survey will focus on key squares surveyed in previous years, with additional allocated sites in likely areas.
The first part of the survey will use the same methodologies, at the same sites that were surveyed during Seabird 2000 and these are shown on the map below as red pins (core resurvey sites). These repeat site counts are required to make meaningful comparisons between the data from Seabird 2000 and Seabirds Count.
However, given the expansion of the urban gull population over the last 15-20 years, an alternative method of estimating the breeding population is necessary. The second part of the survey will consist of surveying a sample of 1km squares in urban areas, shown as orange pins on the map (square survey sites). With such sampling there is a chance that some urban squares will not contain gulls, however, for the data to be statistically robust these squares still need to be surveyed. Survey results will then use correction factors produced through a parallel project, being undertaken by the BTO, to calculate national population estimates.
If you’re able to cover any of the core sites/squares, please email email@example.com and we’ll allocate those to you and flag them as taken on the map.
Both parts of the survey will focus on counts of Herring and Lesser Black-backed Gull, although records of other species will also be recorded. Counts for all three ‘units’ below will need to be recorded:
AON = Apparently Occupied Nest. This is a well-constructed nest or scrape containing eggs or young, or capable of holding eggs (possibly attended by an adult), or an apparently incubating adult.
AOT = Apparently Occupied Territory. This should be estimated by the spacing of birds or pairs on rooftops and observations of apparent territorial behaviour, when actual nests cannot be discerned. Any AONs should also be considered as a territory, so the number of AOTs will always be equal to or greater than the number of AONs.
IND = Individual Adults. This is simply the total number of birds in full adult plumage. Birds in flight can be counted if it is clear that they are using rooftops in the square, but birds observed flying over the square should not be counted.
For each survey square you’ll also need to record:
– Date and time of survey
– A note of any use of gull deterrents or control measures e.g. netting on roofs
– A rough estimate of the % of the square that could not be accessed for survey (i.e. private land)
– Finally, in the comments section note how many of the gulls counted were thought to be away from breeding territories (i.e. flocks of gulls resting on lakes or foraging on a playing field)
Core Resurvey Sites
The locations for the core resurvey sites are those where urban surveys took place during the last census and do not align with grid squares. The extent of these repeat sites is a little random, mainly because this was all rather new (in terms of scale) at the time of the last survey. As a rule of thumb:
– Where the site name refers to a specific town/city/village, use the boundaries of that locality as the boundary of the site.
– Where the site name refers to a specific building/industrial estate/street, use this as the boundary of the site.
– Where a group of sites have a numeric system (e.g. Helston 1, 2, 3), take the grid reference as the centre of what is presumed to have been a distinct ‘colony’. These may have moved slightly so you may have to explore around the general area to locate birds.
We understand that cityscapes change, but do try to stick to these guidelines as much as possible.
Square Survey Sites
The randomly-allocated squares in urban areas will need to be covered from the ground and a link to a map of the square can be found by clicking on the pin. Opening the StreetMap link will then allow you to print off your survey square as an OS map. Some squares may look to be quite ‘rural’, but will have been selected if they have >2% of their areas covered with some form of man-made structure.
We also understand that many areas of the county with breeding urban gulls won’t be covered by either of these survey methods, so we’re also keen to collect the same information for as many sites as possible. We must cover the resurvey sites and square survey sites as a priority, but if you do know of a site that holds birds then these can also be submitted to us to be recorded on the national database. This could be a whole count for a town/village or a specific grid square.
Various downloads are available for the survey, including risk assessments, checklists and most importantly the actual recording form. Once completed, please return the form to firstname.lastname@example.org and we can enter the records onto the national database.