Isle of May National Nature Reserve - Annual Report 2024

• Annex 1: Seabird data
• Annex 2: Puffin census 2024
• Annex 3: Research project summaries

1. Introduction 

The Isle of May National Nature Reserve (NNR) was staffed by the NatureScot team from March until November. Reserve Manager David Steel returned for his tenth season and Assistant Reserve Manager Thomas Skinner returned for his second season. Other organisations involved in working on the NNR include the Isle of May Bird Observatory; the UK Centre for Ecology and Hydrology (UKCEH); Edinburgh University; Manchester University; St Andrews University; the Royal society for the Protection of Birds (RSPB) and the various boat operators bringing daily visitors to the island.  

The seabird breeding season had its highs and lows, with European shags suffering a catastrophic drop in numbers whilst the cliff-nesting auks, razorbill and guillemot, also declined. However, there was some good news as the first puffin census in seven years showed an increase in number whilst the terns returned to nest on the island following last season’s blank year. The summer was HPAI-free although it was detected in early October whilst prey availability appeared to drop for the nesting seabirds in mid-July. The visitor season was disrupted by poor weather throughout the summer although numbers remained high, with 15,000 visitors between April-September. The grey seal season was slow to start and numbers appeared lower than usual, part of a slow decline in the population levels on the island.

1.1 Acknowledgements

The information and data collected for this report came from a variety of sources, including the NatureScot team of David Steel, Thomas Skinner, Bella Allan, Hayley Bannister and Shem Weekes; the UKCEH team of Mark Newell, Josie Hewitt, Francis Daunt, Erin Taylor, Ella Benninghaus and Carrie Gunn; and the Edinburgh University team of Chiara D’Avino and Eve Sharples. Also, thanks to the Isle of May Bird Observatory Trust and members, various boatmen and others who contributed throughout the season.       

2. Biological recording

2.1 Introduction to breeding seabirds

The Isle of May is one of four strategic seabird monitoring sites around the UK, part of the JNCC’s national long-term seabird monitoring programme. The other sites are Skomer, Canna and Fair Isle. The status of seabirds on the Isle of May is also reported to NatureScot for the assessment of qualifying species within the Firth of Forth Special Protection Area. The seabird monitoring programme is completed by NatureScot working alongside UKCEH. This monitoring work makes up the core part of NatureScot’s NNR management work. UKCEH contributes to the seabird monitoring on the Isle of May, under contract to the British Trust for Ornithology (BTO). 

NatureScot staff complete the whole island breeding seabird counts. Every year, reserve staff count the number of breeding cliff-nesting seabirds (fulmar, shag, kittiwake, razorbill and guillemot) and nesting tern species. Staff count the number of breeding ground-nesting seabirds (large gulls, puffins and eiders) every two years. Puffins are now being counted every second year rather than every five years to provide greater detail about status and trends of the puffin colony. NatureScot staff on the island also carry out productivity work for Arctic tern and great black-backed gull (the number of chicks raised per pair). Every year, UKCEH monitors the productivity, return rate, survival and food intake of the auks (guillemot, puffin and razorbill), shags, fulmar and kittiwakes. Other island partners such as the Isle of May Bird Observatory Trust (IOMBOT), Edinburgh University, BTO and St Andrews University provide data on seabird phenology, the date of first eggs laid and chicks hatched. 

Summary of breeding seabirds in 2024

Commencement of the breeding was slow in many species. The winter period 2023/24 saw a number of named storms, some of them arriving in quick succession. Prolonged easterly winds and high swell continued right through to the start of the breeding season, causing breeding to be delayed for most species and particularly late for European shags. The guillemot cliffs were patchy and attendance was low to begin with. Best practice protocols were followed for Highly Pathogenic Avian Influenza (HPAI) all season and there were no confirmed cases of HPAI during the summer months. However, in early October, H5N5 was confirmed in a small group of dead great black-backed gulls on Rona on the north end of the island. The strain H5N1 had been causing problems in recent years but this was the first confirmed case on the island of the H5N5 strain. This followed the pattern of the virus which originated in the northern islands in late summer in the same species and eventually reached the Isle of May in early October. Thankfully, the impact was small as it was outside the main breeding season.

Following all-island counts in May, we saw an increase in:

• puffins (increase from 2017 census)
• kittiwakes (fifth year of increase), and
• cormorants (fifth year of increase)

And a decrease in:

• shag (catastrophic reduction in breeding pairs)
• guillemot (third year of declines)
• razorbill (third year of declines)
• fulmar (third year of decrease)

2.2 Population monitoring of cliff-nesting seabirds

2.2.1 Sections and timings

It is challenging and time-consuming to count cliff-nesting seabirds as the colonies are very busy with birds coming and going and often nesting in inaccessible locations. To capture a snapshot of the Isle of May breeding populations, the breeding birds are counted once during the first ten days of June. The island is divided into the same standardised count sections that have been used in previous years and all cliff-nesting species are counted. Counts from sea (using boat) were added in 2018 to count birds nesting in caves and areas inaccessible from land and included in the all-island population counts. Most of the all-island count was carried out by David Steel from 1-8 June. Mark Newell, UKCEH, counted sections that are sensitive, to avoid disturbing shags. Every year, the monitoring methodology is kept consistent to allow comparison to past counts. The methodology for the five cliff-nesting bird species (guillemot, razorbill, kittiwake, fulmar and shag) is set out in the Isle of May Monitoring Handbook (NatureScot, 2001, revised 2002, 2011, 2021).

2.2.2 Cornerstone plot counts

It is difficult to estimate the actual number of breeding pairs by counting the number of birds on the cliff face because the attendance of auks (razorbill and guillemot) on the cliffs can vary over the course of a day. This is overcome by converting individual counts of birds from the all-island cliff count into pairs using a known k-value. The k-value is the difference between the number of individuals counted at the cornerstone cliff plot at the beginning of an all-island count session and the number of actual breeding pairs known to be breeding at the cornerstone cliff plot from detailed observations made by UKCEH. By multiplying this k-value with the number of individual auks counted during the all-island counts, the total number of pairs across the island can be estimated.

2.3 Results of cliff-nesting seabirds 

Key tables for breeding seabirds can be found in Annex 1 - quick reference guide: 

• Table 6: Phenology (key breeding dates) for breeding seabird species
• Table 7: Seabird population numbers for the six key seabird species since 2019
• Table 8: All-island count of the breeding population of cliff-nesting species by section
• Table 9: Survival rates of the six key breeding seabird species (data provided by UKCEH)
• Table 10: Productivity of the six key breeding seabird species (data provided by UKCEH)
• Table 11: Population counts of the main seabird species, 1980-2024 

2.3.1 Fulmar (Fulmarus glacialis)

We recorded 276 apparently occupied sites (AOS) in 2024 (Figure 2).

The number of breeding fulmars declined by 12% from 314 AOS in 2023 and less than the five-year average of 310 AOS. The first incubating fulmar was discovered on 13 May, the first chick on 7 July and the first chicks fledging on 23 August. Productivity was 0.37 chicks per nest, similar to last year, which was the lowest since 2012.

2.3.2 Shag (Phalacrocorax aristotelis)

We recorded 127 apparently occupied nests (AON) in 2024 (figure 3).

This season, the Isle of May recorded the lowest number of breeding shags on record, declining by 81% from 674 pairs in 2023. This is much less than the five-year average of 512 AON. The decline in shags was linked to mortality from the many North Sea storms over winter and spring (see Weather, Section 9) when birds were unable to forage and died of starvation. The first egg was discovered on 19 April. This was a month later than 2023 (20 March), about the same time as the first chick in 2023 (21 April), suggesting the shags were in poor body condition following winter. The first chick was discovered on 24 May and the first fledged on 28 June. Nesting productivity was 1.64 chicks per nest (1.81 in 2023).

2.3.3 Kittiwake (Rissa tridactyla)

We recorded 5,443 apparently occupied nests (AON) in 2024 (Figure 4).

The number of breeding kittiwakes remained similar to last year, with a very slight increase to 5,425 AON and more than the five-year average of 4,657 AON. This season, there was unusual nest failure in mid-July with chicks observed dead on nests. Some of these dead chicks were swabbed for bird flu but the results returned negative suggesting a starvation event. The chick mortality was also observed at other nearby kittiwake colonies, Dunbar Harbour and St Abb’s Head. Nest building began on 13 May and the first eggs were discovered on 18 May, a week later than 2023. The first chicks hatched from 19 June and the first fledgling was seen on 20 July. Productivity was 0.95 chicks per pair. 

2.3.4 Guillemot (Uria aalge)

We recorded 15,506 individuals with an estimate of 13,372 pairs in 2024 (Figure 5).

The number of guillemot pairs declined by 13% from 15,314 pairs in 2023, the second year of decline and less than the five-year average of 16,577 pairs. Potentially, the decline in breeding populations could either be linked to adult mortality caused by a starvation event the previous autumn (causing a large mixed wreck of adults and immatures up the east coast) or from adults taking a non-breeding year, an effect of the rough winter. Adult birds on the cliffs were observed in poor feather condition indicating poor feeding conditions during the moult period in late June. As the breeding season commenced, attendance was patchy on the breeding cliffs, those that returned appeared unsettled and there was a high rate of egg loss. The first egg was discovered on 2 May, the latest laying date on record, ten days later than in 2023. The first chick was seen on 8 June and the first jumpling (a term used for a chick which fledges the nest) left on 1 July, with the last leaving on 1 August. There were many eggs and chicks lost to a large swell produced by westerly winds in June. Productivity was 0.65 chicks per pair.

2.3.5 Razorbill (Alca torda)

We recorded 4,892 individuals with an estimate of 3,392 pairs in 2024 (Figure 6).

The number of razorbill pairs declined by 20% from 4,223 pairs in 2023, the second year of declines and less than the five-year average of 4,332 pairs. Razorbills were observed with rump areas worn down to the undercoat during the moult period in late June, suggesting poor feeding conditions. The first egg was discovered on 30 April, one week later than in 2023. The first chicks were observed on 5 June and the first chicks seen jumping on 23 June. Productivity was 0.64, about the five-year average. 

2.3.6 Cormorant (Phalacrocorax carbo)

The colony had 34 apparently occupied nests (AON) in 2024.

The cormorant colony continues to go from strength to strength, having originally established on the North Ness in 2020. The use of a drone allowed an accurate count, with 34 nests counted. Nest building occurred in mid-March and the first eggs were being incubated from early April. The first chicks had hatched by early May and the first fledgling was recorded on 26 June.

2.4 Population monitoring of ground-nesting seabird species

2.4.1 Puffin (Fratercula arctica)

We recorded 52,104 apparently occupied burrows (AOB) in 2024. 

The number of puffin AOBs has increased by 33% from 39,000 AOB recorded during the previous census in 2017. It is thought that the breeding population of puffins peaked between 2017 and 2024 and has since dropped. See Annex 2 for full methodology and report of the 2024 puffin census.

Puffins returned to Isle of May waters on 14 March and made landfall on 20 March. The first puffin observed with fish in its bill was on 20 May, indicating that the first chick had hatched. The first pufflings were seen leaving on 27 June. Productivity was 0.77 chicks per pair.

2.4.2 Large gulls

Since 2022, the large gulls on the island have been counted using images taken from a UAV (Unmanned Aerial Vehicle, also known as a drone). This new method of counting was implemented to increase accuracy (allowing the large gulls to be counted in situ on their nests) whilst also reducing disturbance to the breeding bird assemblage across the island, as the previous method involved a large team of people walking across the entire island. The UAV allows a composite image of the island to be taken, imported into geo.View and then a desk-based study implemented counting the various nesting gulls. 

There was an attempt to survey the gull population on 30 May but due to increasing wind speed, the attempt was aborted, and a new survey was conducted on 12 June. The overall totals are shown below.

Herring gull (Larus argentatus)

Present all year round, with the winter numbers supplemented by birds from more northerly breeding populations in Scotland and Northern Europe. Birds were well established on breeding territories throughout April and nest building was noted mid-month. The first eggs were discovered on 27 April, with the first chicks hatching from 29 May. The population survey revealed a total of 3,009 AON, a decrease from the previous survey. Chicks started fledging from across the island from 2 July and, as usual, small numbers remained throughout the autumn, with 400 counted on 27 October. 

Lesser black-backed gull (Larus fuscus)

The entire island population moves south for the winter and the first returning birds were seen in mid-February, with a single on 12 February. As spring progressed, larger numbers arrived across the colonies and the territorial disputes were noted in late March. The first eggs were discovered on 28 April, with chicks hatching by 30 May. The population count revealed a total of 1,250 AON, a decline from 1,739 the previous survey. Chicks started fledging from 4 July and thereafter numbers dwindled and the last confirmed record involved an individual in late October.

2.4.3 Great black-backed gull (Larus marinus)

Present all year round, with influxes of northern birds in the autumn. The island’s small population were on territory by mid-March and the first eggs were discovered on 20 April (15 April, 2023) and the first chicks hatched from 25 May (17 May, 2023). The first chicks started fledging from 10 July. The population survey revealed a total of 111 AON, a slight decrease of 4 nests compared to the previous survey. As usual, post-breeding numbers increased with the onset of the grey seal season as many birds took advantage of dead or dying pups as well as afterbirth in October-December. Interestingly, H5N5 hit a small number of birds in early October, part of a more serious outbreak nationwide. 

2.4.4 Terns

Common tern (Sterna hirundo)

There was a total of 5 apparently occupied nests (AONs) in 2024.

The first birds were seen returning from 8 May and small numbers were evident at the Beacon, the traditional nesting area. However, due to a combination of issues, including carrion crow and peregrine predation, the colony never established. However, five pairs attempted to nest but all eggs were lost soon after. 

Arctic tern (Sterna paradisaea)

There was a total of 324 apparently occupied nests (AONs) in 2024. 

The Arctic tern colony returned after abandoning in 2023 but AONs were less than the five-year average of 453 AON.

The first returning birds were seen on 29 April and by 22 May the colony settled. The first egg was discovered on 24 May, the first chick on 18 June. Unfortunately, no Arctic tern chicks fledged this season as a combination of predation events by herring gulls, lesser-black-backed gulls, and particularly a single short-eared owl took place. On 9 July, the majority of adults departed and by 16 July all adults were gone. This is the second year in a row with no terns successfully fledging. 

2.4.5 Eider (Somateria mollissima)

The colony was not counted this year as we are exploring new counting methodology as well as counting biannually in alternative seasons to the large gull and puffin census years.   

Small numbers overwintered around the island and gradually birds started increasing from late March. The main island loch was the focal point in the spring as large numbers of displaying drakes were present with females. The first sitting female was discovered nesting next to McLeod’s Path on 19 April. The first ducklings were seen on 8 May and thereafter good numbers of young were seen leaving the islands in family crèches. 

2.4.6 Storm petrel (Hydrobates pelagicus) 

We continued to establish storm petrel breeding range, using a hybrid of monitoring methodologies: passive acoustic monitoring, playback and detection dogs. Three storm petrel chicks were ringed, the first chicks ever to be ringed on the Isle of May and potentially the first on the east coast of Scotland. Sophie Bennet of the BTO installed three Passive Acoustic Monitoring devices (audiomoths) to record singing storm petrels within the known breeding area (south of Fluke Street) from 2023 and in new suitable breeding habitat nearby with the objective to estimate the number of singing storm petrels. Detection dogs were brought onto the island to detect scent traces of storm petrels at a new site by the low lighthouse and at the site where they are known to breed. The dogs signalled at 28 burrows, 14 at each site. 

2.4.7 Manx shearwater (Puffinus puffinus)

The island supports the only east coast breeding pair of Manx shearwater in the United Kingdom. The resident male successfully paired with a female this year and the first chick since 2016 was ringed and fledged on 7 September.

2.5 Other breeding birds

2.5.1 Shelduck (Tadorna tadorna) 

As usual, the first birds arrived in late March and up to eight individuals were present, with pair bonding and displaying noted. Due to the secretive nature of their nesting behaviour (nesting underground), it is always difficult to assess the actual number of breeding pairs. It was considered that three pairs bred, and a family party was seen on 9 June. 

2.5.2 Mallard (Anas platyrhynchos)

A total of two pairs bred on the island, with 9 ducklings seen at Bishop’s Cove pools on 6 May, and 4 were seen fledging in late June.

2.5.3 Oystercatcher (Haematopus ostralegus)

Birds were present all year round, with a minimum of 14 pairs nesting across the island (there was no full census this year). 

2.5.4 Feral pigeon (Columba livia domestica)

The species remains a common resident, with breeding recorded throughout the year, with 500 counted in October. 

2.5.5 Swallow (Hirundo rustica)

Another excellent year as birds returned to breeding areas from late April and breeding pairs were found at the Visitor Centre (x2), South Horn, Fluke Street freezer room, Fluke Street engine room and at the main lighthouse. All six pairs were successful in raising at least one brood, and four of these pairs fledged second broods, some as late as early October. 

2.5.6 Rock pipit (Anthus petrosus)

This common resident was present all year round and although the population was not surveyed this year, the breeding population appeared healthy (20 pairs). Pairs were spread across the island and large numbers of young fledged mid-summer. 

2.5.7 Pied wagtail (Motacilla alba)

There was no census of the population this year, but good numbers were present throughout the summer, with successful breeding recorded. Breeding pairs utilised stone walls, buildings and natural nest sites as approximately 15 pairs nested, many producing two broods. As usual, the species departed the island with no over-wintering individuals. 

2.5.8 Carrion crow (Corvus corone)

One pair were present in the spring and three young fledged on 11 June. Birds remained around all season, including ‘Patch’, the distinctive individual which has successfully bred on the island in recent years. 

2.5.9 Peregrine falcon (Falco peregrinus)

For the third consecutive year, the pair nested successfully on the island in the same area as the previous season (on South Plateau). The birds were evident from March and vocal displays commenced from late March. Prey items were very varied, from seabirds to migrant birds, and three chicks fledged successfully from the nest in late June.

2.5.10 Wood pigeon (Columba palumbus)

The first breeding wood pigeons for the island were recorded as recently as 2015 and have since established into a healthy population. As in recent years, a total of six pairs bred on the island and at least three of these pairs were ground-nesting, showing the variety of sites the birds can use. 

2.6 Migrant birds 

The Bird Observatory opened its doors on 6 April and occupancy was excellent once again. The only two weeks not occupied during the season were 20-27 April and 24-31 August. As usual, weather played a factor for groups arriving on the designated Saturday but in general it was a smooth season. The NatureScot team provided transport service of all kit and equipment across the island throughout the year. As usual, the bird observatory members concentrated on recording bird migration through daily census and bird ringing operations. 

It proved a tale of two seasons as spring was excellent, producing some noteworthy arrivals whilst autumn was quiet, with just a few highlights. A total of 169 species were recorded, the sixth highest ever annual total. 

• 4^th - White-billed diver
• 4^th and 5^th - Spoonbill
• 9^th - Great shearwater
• 9^th - Great crested grebe
• 14^th and 15^th - Radde’s warbler 

Other noteworthy arrivals included:

• Balearic shearwater: Single on 17 August
• Grey-headed wagtail: Single on 2-4 May
• Wrynecks: Two from 3-7 May and one on 8 September
• Nightingale: Single on 2 May
• Bluethroat: 17 during spring
• Red-backed shrike: 12 in the spring
• Marsh warblers: Singles on 13 and 18-20 May
• Icterine warbler: Four between 21-26 May
• Yellow-browed warbler: Total of 55 in autumn
• Common rosefinch: Single from 22-27 May and record influx in autumn
• Red-breasted flycatcher: Single on 27 May
• Nightjar: Male on 27 May
• Hawfinch: Male on 1 and 2 April
• Hoopoe: Single on 9-16 April 

For a full account of bird records, check out the Isle of May Bird Observatory website

2.7 Mammals 

2.7.1 Rabbit (Oryctolagus cuniculus)

The rabbit population remained very healthy across the island although it was evident that myxomatosis was in the population during the spring. Originally discovered in rabbits at the south end of the island, the disease spread slowly across the island, reaching the North Plateau area by mid-October. The result was that a large number of rabbits died, with corpses littering the island. This was the first major outbreak since 2013, and next season will prove interesting from the vegetation perspective. 

2.7.2 Grey seals (Halichoerus grypus)

The grey seal season was very slow to start, mirroring the previous year. The first pup was discovered on 7 October and it was a poor start, with the first eleven pups all succumbing at an early age. However, the colonies soon became occupied although it was evident that numbers were lower than usual. Ground counts undertaken on 5 November to compare with counts on the same date in recent years revealed a drop of 49% on the previous count on the same dates in 2022 and 2021. This drop might have been due to a number of factors, including a late start to the season. However, this is continuing the trend of a slow decrease in the size of the Isle of May grey seal colony. 

2.7.3 Cetaceans

It was another good season for cetacean sightings (cetaceans are aquatic mammals that include whales, dolphins, and porpoises) as a total of six species were recorded in the surrounding seas. Annual cetacean counts typically return only 3-4 species, with minke whale (17 out of the last 18 years), harbour porpoise (16 out of the last 18 years) and bottle-nosed dolphin (13 out of the last 18 years) the island’s most regular reported. The months of August and September proved (once again) to be the most productive months. 

Minke whale (Balaenoptera acutorostrata)

This season, minke whales were the most frequently sighted cetacean, with records on 22 dates (33 dates in 2023) and typically most were seen during August (8 days) and September (4 days). The first of the year was noted in early May with a single on 10-11 May followed by the same animal on four dates from 24-31 May. The majority of sightings involved single animals, with reports on 17, 19 and 27 June and eight dates in August. Peak counts included four on 4 September and three on 4 October. 

Harbour porpoise (Phocoena phocoena)

There were reports on 14 dates (28 in 2023) across the season and the poor weather of summer (windy conditions on the vast majority of dates) did not help recording. Records were noted on three May, one June, five August and five September dates. The majority of records involved 2-3 animals but an impressive 40 were seen on 4 September off the east and north of the island.  

Bottle-nosed dolphin (Tursiops truncates)

The species is frequently seen along the Fife coastline and reported by boatmen throughout the summer, but these animals are just outside our recording area. The species is much rarer around the island but this year it was well reported, with records on fifteen dates (five dates in 2023). The majority of pods involved 4-20, although counts exceeding this included 25 on 29 September and 35 on 4 October.   

Humpback whale (Megaptera novaeangliae)

An individual was seen surfacing off the east side of the island on 8 May and appeared to be a young animal. Reports are increasing from the island as there have been records in 2015, 2018, 2022 and 2023.   

Common dolphin (Delphinus delphis)

For the second consecutive year, a pod was seen as 50 animals were noted off the east side of the island on 29 September. This follows on from 60 on 25-26 August 2023. Previous to this, there are only a few records from the island, and this was the first since two animals were recorded in 2016. 

Sei whale (Balaenoptera borealis)

For only the third ever occasion (although the second consecutive year), the island produced a record. A large animal surfaced close to the north-east corner of the island on 28 August and was seen feeding north of the island later that day. This is only the third ever record following individuals in 2023 and 2021.

2.8 Lepidoptera

2.8.1 Butterflies

We recorded butterflies using transects for UKBMS as well as casual recording from staff and the bird observatory. Nine species were recorded on the island from April – May (average 10 species seen per season). The seven most common species included red admiral, small tortoiseshell, small white, large white, green-veined white, peacock and painted lady butterflies. These seven species of butterfly have been recorded every year since 2007, excluding 2020 when no staff were present on the island due to Covid-19. Red admiral was the most frequently occurring (102 days) and most abundant species (413 records), peacock was the second most frequently occurring (41 days) and second most abundant (117 records). Speckled wood was first recorded as recently as 2017 but has now been recorded in five years since, including an individual in October. A similar pattern has occurred with wall brown, as the first island record occurred in 2018 but it has been seen in six years since, including an individual in August.

2.8.2 Moths

We trapped moths using a Skinner MV light trap on 27 nights between 4 April and 2 August. The trap was positioned in the principal keeper’s garden and moved under shelter on wet nights. A total of 109 species were identified over the season, comprising 2,456 individual specimens. Marbled coronet was the most frequently occurring species, present on 21 occasions, followed by bright-line brown-eye, present on 18 nights, and silver Y, present on 14 nights. Dark arches was the most abundant species, with a total of 884 specimens counted, followed by marbled coronet with 316 specimens and chrysoteuchia culmella with 142. 

We recorded marbled green, Nyctobrya muralis, for the first time on the island. One of the big highlights was the discovery of a convolvulus hawk moth Agrius convolvuli in September, which had only been recorded on four previous occasions (this season being the second season in a row).

3. Research and monitoring

3.1 Research teams 

As usual, research teams were based on the island throughout the year, studying various aspects of the island’s flora and fauna. The research teams totalled 1,023 bed nights on the island, demonstrating the importance of the island for research. During the summer months, the UK Centre for Ecology and Hydrology (UKCEH), led by Francis Daunt with field manager Mark Newell, were present from 17 April until the end of July. The team included Mark Newell, Josie Hewitt and Erin Taylor, supported by Ella Benninghaus, Carrie Gunn and Sarah Burthe amongst others. Edinburgh University, led by Emma Cunningham, had a team of four present throughout the summer months looking at HPAI and European shags. During the autumn months, Manchester and Edinburgh University worked together on the island’s mice, and they were based in Fluke Street from 27 August-3 October and again from 5 November-13 December. 

Please refer to Annex 3 for research report summaries.

4. Visitor review

The island opened its doors on 1 April and remained open until 30 September, with planned closures one day per week in the months of May and June, whilst, as usual, boats were cancelled due to bad weather on several dates. 

The visitor boats departing from Anstruther brought most of the visitors, with the May Princess bringing 11,018 visitors (11,470 last year) whilst the fast RIB Osprey carried a further 1,610 visitors (1,655 last year). During the season, boats travelled from the Lothian side of the Firth of Forth with the Seabird Centre RIB, Seafari Express, bringing 1,389 visitors (1,417 last year) and BlueWild a further 525 visitors (616 last year). Small private leisure craft, cruise ships (two) and kayaks carried a further 245 visitors, bringing the annual total to 14,787 people compared to 15,603in 2023.

5. Media coverage

The Isle of May appeared regularly on various media outlets throughout the year: 

• STV television and The Courier carried coverage of the puffin census
• UKCEH podcast ‘Counting the earth’ series, episode ‘Puffin Patrol on the Isle of May’
• A segment about seabird declines on BBC Radio 4 show ‘Inside Science’, episode ‘How green is space travel?’

Social media was again very popular, with the island’s blog attracting a record of 105,051 hits by 46,647 visitors. Overall, 104 different blog posts were posted highlighting the wildlife and the work done on the island. Facebook remained popular, with 5,500 people following the page. 

6. Volunteers and support

The island’s long-term volunteer programme continued this season. Bella Allan and Hayley Bannister joined the team working between May and early September, contributing a total of 240 man days. Further help and support was given by short-term volunteers Corin Woodhead, Finley Dennison, Meg Stone and Jaline Wilson, contributing a further 87 days. 

NatureScot volunteer groups also offered good support, especially with larger projects including the puffin census, weeding of the priory, open days including the Doors Open day event, tern management and closing down the island. 

7. Infrastructure and island work

As usual, various island work was undertaken during the season, dependent on weather and the seabird breeding season. Jobs included:

• Boardwalk extension along Holyman’s path to protect puffin burrows
• Main road and Kirkhaven jetty concreting following damage with Storm Ciaran in October 2023
• Painting of interior of the South Horn
• Grey water pipe replaced and painted
• All chimneys relined in all three buildings in Fluke street
• All showers repaired
• New water tank installed behind engine shed (moved from Visitor Centre)
• Exhibition room in lighthouse painted

7.1 Water supply

Water continued to be a problem for island life this season. Drinking water is extracted from a well which does not replenish over the dry summer months and June, July and September were very dry months (See section 8.5: Rainfall).

7.2 Boat activity around the island

Boating activity was recorded around the island by the island residents from the end of May to the end of July. It is important to note that this was based on incidental sightings, recorded by varying numbers of island residents while engaged in other tasks, and is by no means a complete record of all boat activity in these months. Despite this, a total of 13 incidences of boats coming within the voluntary limit of 50m from the island were observed: four leisure crafts and nine fishing vessels, mostly creel boats setting lobster pots and one vessel trawling for mackerel.

8. Weather

During the 2023/2024 season, we have, for the first time, been able to collect hourly weather observations directly on the island from professional-grade weather stations. Two Davis Vantage Pro stations were installed in mid-2023 (acquired through the Isle of May Mouse Project), with ongoing maintenance, data collection and data processing facilitated by a NatureScot weather volunteer role. The stations monitor air temperature, rainfall, humidity, wind speed and wind direction. Two further sub-modules monitor ground temperature and moisture at two depths. We now have a full 12-month record which allows a number of insights to be made.

8.1 General climate

Comparison with nearby observations on the mainland (Leuchars Met Office station, Fife) for the 2023/2024 season show that the island generally experiences less extreme temperature variations (cold periods are milder, hot days are cooler) and significantly higher wind speeds (gusts frequently exceed 50 mph). There are also indications that the island experiences less rainfall compared to nearby coastal areas.

8.2 Wind direction

While the predominant wind direction on the island is westerly or south westerly, we have seen significant variation on a monthly basis. Specifically, October 2023 and March, April, May and September 2024 saw a significant fraction of winds arriving from easterly directions.

8.3 Wind speed

The 2023/2024 season saw a large number of named storms, some of them arriving in quick succession. Many of these can be seen directly in the wind speed record for the island. Storms Babet, Gerrit, Isha and Kathleen were particularly keenly felt, with wind speeds reaching 85 mph during storm Isha in January.

8.4 Temperature

We did not see temperature extremes on the island, with a maximum of 23°C in August 2024, and temperatures dropping just below freezing on only one occasion in January 2024.

8.5 Rainfall

Observed rainfall appears to vary quite considerably on a local scale around the coastline of Fife and East Lothian, making direct observations on the island particularly valuable. Rainfall on the island appears to be most similar to (although somewhat lower than) the SEPA observations at St Monans, located approximately 13 km ENE from the island on the Fife coast. Using this as a reference point, we are able to infer how typical the rainfall in the current season was compared to the long-term (2014-2023) average. 

Total rainfall on the island appears to have been a little higher than average; however, there was significant monthly variability. The months of October and December 2023 and April 2024 were significantly wetter than average, while June, July and September 2024 were significantly drier. Since these are some of the busiest months on the island, this dry spell resulted in quite a strain on island water resources. September in particular saw an extended dry spell with rainfall of less than a quarter of the long-term average. This resulted in critical water shortages towards the end of the month.