Red Squirrel Monitoring Report Spring In partnership with

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1 Red Squirrel Monitoring Report Spring 2017 In partnership with 1

2 Introduction The spring monitoring of the North Merseyside and West Lancashire Red Squirrel Stronghold was conducted throughout March to May 2017 using three different surveying techniques; visual transects, hair tubes and trail cameras. All visual transects were completed within a 3 week period in March. 16 sites throughout the reserve woodlands of Formby, Ainsdale and Altcar were surveyed. A further 14 woodlands within the buffer zone were surveyed covering Little Crosby, Ince Blundell, Halsall, Southport and Scarisbrick. An additional 3 woodlands outside of the stronghold were also monitored covering Knowsley Estate and Mere Sands Wood. Figure 1: Map showing the boundary of the North Merseyside and West Lancashire Red Squirrel Stronghold. Reserve woodlands 16 visual transects were carried out throughout the reserve woodlands. Hair tubes were placed along 5 of these transects. Grey squirrels were not seen on any of the visual transects but were detected in one of the hair tubes at Altcar Rifle Range. The highest number of red squirrels seen on one transect in the reserve woodlands was 25 squirrels at a site at National Trust Formby. This transect has consistently had a high density of squirrels for the last 3 monitoring sessions. 18 were also seen during one walk on another transect at this site. Overall, red squirrel numbers throughout the reserve woodlands have increased since last spring and the population is now at 97% of the 2002 level (see Figure 2). This increase is probably due to a mild winter and good food availability which allowed breeding to start early this year. Usually, the first litter is born around March, but in February this year a red squirrel kitten was found orphaned which was already approximately 4 weeks old. 2

3 Index Index Red Squirrel monitoring - reserve woodlands Year Figure 2. Bar chart showing the changes in the spring red squirrel reserve population between 2002 and The overwinter survival of red squirrels is calculated by taking the average numbers seen on spring transects as a proportion of those in the autumn of the previous year. Figure 3 shows the survival of red squirrels in the reserve area over the past 5 winters has been reasonably consistent but with a significant increase this year Overwinter survival of red squirrels - reserve woodlands Year Figure 3: A bar chart showing the overwinter survival of the red squirrel population in the reserve between 2002 and Buffer zone 14 sites throughout the remaining stronghold were surveyed. Visual transects were conducted at 11 sites. Hair tubes were used as an additional survey method at 5 of those 11 sites. Three woodlands were 3

4 monitored using trail cameras. Table 1 shows a summary of the presence of red and grey squirrels throughout these sites. Table 1. The number of sites in the buffer zone with red squirrels, grey squirrels, both species and no squirrels. Red squirrel Grey squirrel Both species None only only Number of sites There has been a significant improvement since Spring 2016 when Orrell Hill was the only site with red squirrel only presence. This has increased to 4 sites with red squirrels only presence this Spring Orrell Hill, Ben s Gorse, Southport Crematorium, Halsall. In total, no squirrels, either red or grey, were seen at only 2 sites. These were both sites where trail cameras were used Formby Moss and Scarisbrick Moss. Both red and grey squirrels were detected at Church Wood and Flea Moss Wood in Little Crosby where grey squirrel management work continues. Three of the sites with grey squirrel only presence continue to be Hesketh Park and Botanic Gardens in Southport and also at Scarisbrick. Hesketh Park again had the highest number of greys seen on any of the transects. In the 3 sites outside of the stronghold, only grey squirrels were detected. However, at Mere Sands Wood Red squirrels are regularly sighted by volunteers and visitors so they do remain, albeit at a low density. Only grey squirrels were detected in the woodlands at Knowsley Estate. We are continuing to work with Knowsley to safeguard the remaining red squirrel population and we know they are still present but it highlights how important it is to maintain continuous conservation effort. Figure 4 is a map showing the distribution of red squirrels, grey squirrels and both species of squirrel recorded in the standardised monitoring throughout the North Merseyside and West Lancashire Red Squirrel Stronghold. Also shown on the map are the monitoring transects at Knowsley Estate and Mere Sands Wood. Public sightings and grey squirrel control data Grey squirrel control is undertaken in woodlands throughout the stronghold by the Red Squirrel Ranger and volunteers and records kept of all captures and sightings. Sightings of red and grey squirrels reported by the public are also recorded. Neither of these sources can be used independently to give an accurate interpretation of squirrel distribution, but the data can be combined with the standardised monitoring results to further inform our knowledge. Figure 5 and Figure 6 show the current distribution of red squirrels and grey squirrels respectively in North Merseyside and West Lancashire from the combined data. 4

5 Acknowledgments Thank to you all staff and volunteers who undertook surveys and also to the many landowners who continue to grant access to their woodlands. Rachel Cripps, Lancashire Wildlife Trust, July Figure 4. Spring 2017 standardised monitoring results in the North Merseyside and West Lancashire red squirrel stronghold and Knowsley. Map shows presence of red squirrels, grey squirrels and both red and grey squirrels in 2km x 2km squares. 5

6 Figure 5. Red squirrel distribution in North Merseyside and West Lancashire. Map shows the presence of red squirrels in 1km x 1km squares. Results compiled from public sightings, control records and standardised monitoring from January 2017 to June Figure 6. Grey squirrel distribution in North Merseyside and West Lancashire. Map shows the presence of grey squirrels in 1km x 1km squares. Results compiled from public sightings, control records and standardised monitoring from January to June 2017.

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