In summer 2024, we launched the Coreo House Martin Mapper app  — a dedicated citizen science tool to record house martin nest sites, nesting activity, and mud collection sites.

The data collected through the mapper will provide formal records of nest locations and will play a vital role in conserving and protecting nest sites, and enabling conservation bodies, public groups, or private individuals to consider the expansion of existing colonies. 

Recorded information on the mapper, especially when completed annually, will also help us to build a better picture and gain better insights of house martin migration patterns back to the UK, nest usage, and breeding activity, and enable the charity and conservation bodies to consider further initiatives to aid and protect house martin populations.

We thank you in advance for using house martin mapper; collectively we can observe, record, and protect house martins breeding in the UK & Ireland.

Unlike ‘Swift Mapper’ data doesn’t feed directly to other conservation charities, but we have signed up to provide annual data to recording and research bodies in the UK & Ireland: the National Biodiversity Network (NBN) Atlas, the National Biodiversity Data Centre (NBDC), and Local Environment Record Centres (on a not for profit basis).

We can also make data available to the BTO, local ornithological societies, and the RSPB, (for example) upon their requests. 

The sharing of information can help inform planners, ecologists, developers, researchers, bird clubs and conservation bodies, and help protect existing colonies, guide planning decisions, and ensure that mitigation measures are properly targeted.

The app enables you to record details of house martins nesting within your location or at other colonies, along with a facility to record mud collecting data too.

The best way to support the project and use the mapper is to provide a record for each building where nests exist, on an annual basis.

Make one record for each building, and edit that record through the breeding season to update information by adding any new nests that house martins make, new occupancy of nests, any nest collapses during the season, and to tell us how many broods you think the site produced.   

At the end of the breeding season, there should be one single record per building, and the data for nests and occupancy of nests should be the maximum number during the season.  The comments box can also be used to provide extra information for example if house martins had 2 broods, or whether new pairs of house martins appeared later in the season to nest.

Records are equally important if a building that has nests on them did not have any house martins returning to them in the year, or if all the nests were lost overwinter and house martins did not rebuilding in the new season.

We encourage the use of the mapper to report nest site locations even if they have been reported on our social media platforms, as it enables us to more readily store and access the information, and utilise and share the data to refine and enhance our conservation efforts.