Wild geese can carry bacteria, viruses and parasites that pose health risks to both livestock and humans, as well as bacteria that have become resistant to antibiotics. The numbers of greylag geese present on Orkney have risen dramatically over recent years, with an estimated 20,000 resident geese and an additional 40,000 migratory geese arriving from Iceland during the wintering season. The increased density of geese on farmland pastures results in high levels of faecal contamination and this project aims to investigate these microbial risks, assess the potential effects on both livestock and human health, as well as the subsequent economic and social impacts of this dramatic change in biodiversity. To investigate potential risks from Cryptosporidium carried by geese, DNA, which was extracted from goose, cattle, and calf faecal samples and drinking water reservoir samples in Year 2, has been screened for Cryptosporidium DNA using molecular methods (PCR). To aid assessment of transmission routes and allow for comparison between the different sources, the species of Cryptosporidium in each positive sample has been determined using sequencing methods and PCR. Any samples which were positive for C. parvum, the main species responsible for zoonotic infections and clinical disease in calves, were screened using a quantitative PCR to determine the burden of parasites. Campylobacter is a bacterial pathogen that causes gastrointestinal disease in humans and sometimes reproductive failure in livestock. To investigate risks of transmission of Campylobacter between geese and cattle, DNA has been extracted from isolates from goose, cattle and calf faeces and environmental samples, and whole genome sequencing data has been generated. This will allow comparison of genotypes from each cohort and datasets can be interrogated to identify transmission events. We also aim to assess the risk of transmission of antimicrobial resistant bacteria between geese and cattle by using molecular analysis to detect the presence and abundance of resistance genes in faecal samples. Methods to extract bacterial DNA from different sample types were compared and DNA has been extracted from samples for analysis in Year 4. DNA from goose faecal samples has also been extracted for genotyping analysis of host DNA. This will enable identification of faeces from different goose species and the method may also allow investigation of goose population structure and discrimination between migratory and resident cohorts (Years 4 and 5). Correlations between goose genotype and pathogens will also be investigated. All KE Objectives were completed by project PIs including engagement with farmers on Shetland, a site where numbers of geese are reported to be increasing. Individual farm reports were also generated for Cryptosporidium data and distributed to farmer participants. The team prepared contributions to Ecosystems and Land Use Policy Engagement Group (ELPEG) bulletins, and the project was presented by the project lead at the annual  Ecosystems and Land Use Stakeholder Engagement Group (ELSEG) meeting.

Impact:

Policy: The project was highlighted in an entry for the SEFARI SPARK Newsletter which resulted in a request from the Cabinet Secretary for Rural Affairs, Land Reform and Islands for further information on the project. The project PI described the project in a “Technologies for AMR detection” presentation for the Minister for Agriculture and Connectivity of Scotland as part of antibiotic resistance awareness week. The project PI outlined the project to policy audiences at the Wednesday Learning Session for the Scottish Government’s Biodiversity Unit. Campylobacter data from the project contributed to a Food Standards Agency Report “Genomics of antimicrobial resistant Campylobacter transmission through UK Agri-Food systems” (April 2024) as part of the Pathogen Surveillance in Agriculture, Food and Environment (PATH-SAFE) Programme.

Industry: Members of the project team held discussions with farmers from Orkney, Lewis, Harris and Shetland as part of a pan-island network with shared interests. Farmers highlighted areas of interest for further studies on geese, including issues relating to Campylobacter and sheep. The project PI presented the project at a Scotland Food & Drink Partnership Sustainability Discussion which led to a request for further information and engagement with the group.

Public and professional: The project team hosted and presented research within MRI-D4-2 at the Scottish DNA Hub meeting in Feb 2025. The group discussed action plans for future Hub activities including sharing tools, methods and samples, and plans to develop a web-interface for the group to promote engagement.

This year, we have successfully achieved all the technical objectives of the project. We have successfully collected faecal and environmental samples from two study farms, with goose samples collected from two additional farms. Four batches of Scottish Water samples were also collected over 6-months and processed for detection and speciation of Cryptosporidium. These goose, cattle and calf faecal samples, as well as the water samples, were processed to isolate Cryptosporidium oocysts for subsequent extraction of protozoan DNA. Faecal samples were also processed for Campylobacter culture using enrichment broths and selective culture plates. Sub-samples were also archived for host genotyping and detection of antimicrobial resistance genes in years 3-5. Faecal samples from Icelandic geese have been collected, shipped and archived, and extraction of DNA from this migratory cohort was successful, yielding DNA that is of sufficient quality and quantity for molecular analysis.

All Knowledge Exchange Objectives were also successfully completed by project Principal Investigators. These activities contributed to the project impact, extending to policy, industry and public engagement:

Policy: Expertise within this group, related to detection of microbial risks in wild birds was called upon through participation in the NatureScot Scientific Advisory Committee sub-group on HPAI (Highly Pathogenic Avian Influenza) and attendance at an HPAI workshop, Research For Recovery, hosted by the Joint Nature Conservation Committee (JNCC) and Defra. The project was outlined within the Ecosystems and Land Use Policy Engagement Group bulletin for distribution amongst stakeholders from Scottish Government and key government agencies including NatureScot and SEPA, and was presented by the project lead at the annual ELPEG and ELSEG (Ecosystems and Land Use Stakeholder Engagement Group) meetings. 

Industry: The project lead was invited to run a workshop focussing on research and surveillance of HPAI within a NatureScot event for stakeholders with an interest in the impact and management of avian flu in wild birds including those involved in site management, wildlife tourism, wildlife rescue, wild bird monitoring and research.

Public and Professional: The project aims and scope were outlined to the general public and farming community at the Royal Highland Show, which presented opportunities to discuss experiences with wild geese on farms across Scotland. A project update document was prepared for circulation around stakeholder groups and farmers in Orkney.

Wild geese can carry microbial risks such as bacteria, viruses and parasites that can cause disease in both livestock and humans, as well as bacteria that have become resistant to antibiotics. In recent years, the numbers of greylag geese on Orkney have risen rapidly, with approx. 20,000 resident geese present all year round and approx. 40,000 geese arriving from Iceland during the wintering season. Given the high level of faecal contamination arising from the extremely high density of geese on farmland pastures it is important to investigate these microbial risks, assess the potential effects on both livestock and human health, and consider the subsequent economic and social impacts of this dramatic change in biodiversity. Specifically, we aim to investigate the transmission of Cryptosporidium between geese, cattle and calves and assess the risk to livestock health, establish carriage levels and transmission of Campylobacter, which is the biggest bacterial cause of human gastrointestinal disease in the UK and an important foodborne pathogen as well as investigate whether or not the geese have a role in spreading bacteria which are resistant to antibiotics. We also aim to develop laboratory methods to genotype the geese, which may enable different populations / family groups of geese to be identified and potentially enable migratory geese to be discriminated from resident geese. We have achieved each of the Year 1 Objectives (O), as detailed below: Sampling campaigns were planned following discussions with BioSS and representatives from the Orkney Goose Management Group (O1.1). Methods for sample collection and processing were assessed and optimised to ensure stability of samples for transport following field collection (O1.2).  Methods for Campylobacter culture from goose faecal samples were optimised to ensure maximum recovery of this fastidious bacteria (O3.1). To enable assessment of microbial carriage during the wintering season on Orkney, 200 goose faecal samples were collected from 9 farms (O1.3). Samples collected in O1.3 were processed for Campylobacter culture using enrichment broths and selective culture plates (O3.2) and to isolate Cryptosporidium oocysts and subsequent extraction of protozoan DNA (O2.1). Sub-samples were also archived for host genotyping and detection of antimicrobial resistance genes in years 2-5. Methods to extract goose DNA from faeces were assessed and optimised using local faecal material. Quality of DNA was assessed alongside molecular methods to amplify host DNA for sequencing enabling selection of an optimal method (O5.1). All KE Objectives were completed by Project PIs including an initial kick off meeting with Orkney Goose Management Group representatives, attendance at two Ecosystems and Land Use Policy Engagement Group (ELPEG) meetings and preparation of material for the ELPEG bulletin (KE6 and KE7), and one Ecosystems and Land Use Stakeholders Engagement Group meeting (KE16). There have been no deviations from the original work-plan.
 

Impacts:

Policy: Expertise within this group, related to detection of microbial risks in wild birds was called upon through participation in the NatureScot Scientific Advisory Committee sub-group on HPAI (Avian influenza): wild bird surveillance, monitoring and research. The project was presented to the Cabinet Minister For Rural Affairs and Islands, Mairi Gougeon and Dr Sheila Voas, Chief Veterinary Officer, Scotland, as well as to visiting groups of Rural and Environmental Science and Analytical Services, raising awareness of the need  for research focussing on microbial risks associated with rapidly expanding wildlife populations. The project was outlined within the Ecosystems and Land Use Policy Engagement Group bulletin for distribution amongst stakeholders from Scottish Government and key government agencies including NatureScot and SEPA. Discussions were also held with Scottish Water to arrange collection of suitable water samples for analysis.
Industry: An article was published in the Orcadian newspaper describing the project, which raised awareness of the work and assisted with farmer recruitment.
Public and Professional: The project was presented within a seminar entitled Zoonoses and antimicrobial resistance in Scottish wildlife populations at the University of Saskatchewan, Vaccine and Infectious Disease Organisation, Canada. Engagement activities at the at the Biggar Science festival and the Royal Highland Show provided an opportunity to discuss the project aims and scope with the general public."