Welcome to the latest news and updates from the Orkney Native Wildlife Project
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Monitoring our native species and what to do if you want to be involved
Running alongside the eradication arm of the project, which deploys thousands of traps to eradicate the stoat, is the research and citizen science programme.
This team focuses on recording the data to monitor the population of selected species in Orkney deemed most threatened by the non-native stoat. As the eradication progresses year on year this information also examines how this invasive non-native predator is impacting on Orkney’s native wildlife.
The monitoring to observe specific species takes place between April and July. The Orkney vole is also monitored again in September. We recruit seasonal monitoring staff for this, but volunteers wanting to take part in this citizen science project are vital. In 2019, 1142 hours were volunteered to help the project monitor Orkney’s wonderful native wildlife. If you are interested in volunteering for the 2021 season, please contact our Monitoring Officer, Zoe Edwards.
Our monitoring sites are spread throughout areas of Mainland Orkney as well as the outer isles. Although there is no evidence of stoats on these isles, it allows for an annual comparison between areas with and without stoats. This photo shows Amy King, Monitoring Officer 2019, out in the field on Rousay
The research is focused on species most likely to be affected by stoats, collecting and analysing data throughout the lifetime of the project and comparing this to historical data pre-stoat arrival in 2010, as well as pre-eradication (where available).
For voles, skylarks and meadow pipits, the surveyors visit the chosen sites and pick a ‘transect’, which is a line across a habitat or part of a habitat. The transects we use are one-kilometre lines across an area, pre-determined to be the same place at each time for accurate comparison. The surveyors record specific observations along the line depending on what they are looking for. For instance, with the Orkney vole, this involves stopping at 25 GPS marked points 40 metres apart along the transect line and recording what is found within an area known as a ‘quadrat’.
For those that don’t know, a quadrat is a frame which is traditionally square. It is used in ecology and geography to isolate a standard unit of area for consistent study of the distribution of a chosen subject over a large area.
A map showing a survey area at the RSPB Trumland
The quadrats we use are relatively small, just 300mm square, and these are square templates that are thrown at each of the identified 25 points, to land within three metres of the transect line. This ensures we are unlikely to survey the same spot each time.
A quadrat is a simple tool, yet an effective oneOnce on the floor, the surveyors inspect the vegetation to search for signs of vole activity, such as clippings (from feeding) and their poo. To find these signs you must pull the vegetation to one side carefully all the way to the earth, looking closely at what is uncovered.
Below is a summary of the results of the 2019 monitoring season on the Orkney vole, skylark and meadow pipit. We must thank all the volunteers, the Orkney Raptor Study Group, and our partners for their help gathering the essential monitoring data for the season. With the valuable help of the Orkney Raptor Study Group (ORSG) and the RSPB we are also monitoring other bird species potentially affected by the invasive non-native stoat. Look out for more information on these bird populations in a future issue of our Stoat Snippet.
Orkney vole (Microtus arvalis orcadensis)
We monitor the vole population each year on 31 sites across Orkney Mainland, the linked isles and the four stoat-free islands of Eday, Rousay, Sanday and Westray. Data from these sites will be checked against historic data from before 2010 (when stoats were first reported in Orkney) as well as each year of the project.
These surveys are completed in the spring and autumn across the Orkney Mainland - four in the linked isles and eight in the North Isles. The 2019 season showed a significant drop in the abundance of voles on West Mainland sites since 2008. In the last 10 years the population has steadily dropped back from a peak to the pre-stoat numbers recorded in 1999/2000 - 10 years before the stoat was first sighted on Orkney. In the autumn there were more signs of voles on the stoat-free Northern Isles compared to the Orkney Mainland.
Meadow pipit and skylark
These birds are known collectively as passerines. We monitor their population estimates and breeding success annually.
We consider a nest is successful if any of the clutch of eggs found at the nest has hatched. When at least one chick fledges from the nest this is considered a ‘breeding success’. The productivity of each species is determined by calculating the nest successes from the samples found during the breeding season monitoring. From that we estimate the overall number of a species in an area to have a better idea of their population by area. By knowing what birds are in an area we are surveying, we can estimate their productivity.
These surveys involve recording birds seen in front and to the side of the person recording, noting the behaviour, age and distance from the transect line. We survey these at the same sites as the Orkney vole in May and June. The 2019 survey results show both the meadow pipit and skylark population have increased since 1998/1999/2000 in West Mainland. Their population now is similar between the islands and Mainland.
Meadow pipit nest, South Ronaldsay
Waders – curlew, lapwing, oystercatcher, redshank and snipe
We also monitor wader breeding success across Orkney Mainland, the linked isles and other islands. We focus on curlew and lapwing, including monitoring the nests we find and their broods until they succeed or fail. In addition to this, large-scale population monitoring surveys were undertaken in the first year of the project (2019) to provide a benchmark for the repeat of the survey in the project’s final year. The comparison with late 2000s data shows greater declines of curlew on the Orkney Mainland than the islands. Lapwing, oystercatcher, redshank and snipe face similar declines.
Lapwing (RSPB images)
Join our monitoring team!
We are looking for enthusiastic, skilled, and experienced fieldworkers to join the project from March 2021 for a few months. Monitoring the populations of Orkney's native wildlife is an integral part of the project and these researchers will join our volunteers to carry out a programme of wildlife surveys between March and July 2021.
Details on how to apply before the deadline of 18 January 2021 are online.
Happy Holidays
As we come to the end of an extraordinary year for everyone, we hope you enjoyed a hearty, merry Christmas and wish you and yours a healthy New Year.
A trap round overlooking Hoy (Kinlay Francis)
See you in 2021!