Ghostly White

RSPB Mersehead Blog 26^th October – 1^st November 2024

Barnacle geese are arguably the star attraction of the reserve and numbers have been building steadily over the past month as the geese return from their breeding grounds in Svalbard. A peak count for the reserve so far this autumn has been 8,930. Amongst the thousands the black and white stripes, there have been five ghostly pale birds – these are leucistic Barnacle Geese. Leucism is a genetic mutation that causes partial loss of pigmentation. In birds, this either results in some unusual white feathers or a whitish colour all over. If you look closely at the below photograph, you can see some of the usual Barnacle Goose patterning appearing in the leucistic bird as a washed-out grey colour both on its back and up its neck.

Photo credit: G. Chambers.

With some determination it is possible to analysis photographs of the different leucistic birds to identify individuals from the varying levels of black pigmentation showing though the feathers. For example, in photograph A, we can identify that the same bird has been photographed twice by the corresponding black features. Photograph B clearly shows two different birds.

Above Photograph A and Below Photograph B - Photo credit: G. Chambers.

Starlings have roosted in the Mersehead reedbed for at least the past 10-years and have just started to gather again over the past week. An estimated 3,000 birds came into roost on Thursday evening this week with the murmuration starting at 16:15. As the day length becomes shorter going into winter, the murmuration will occur earlier, usually around an hour or so before sunset. With as many as 40,000 birds estimated in past years, we hope to see the murmuration increase in size over the coming weeks. Starling murmuration’s are an incredible wildlife phenomena thought to deter possible predators by creating a confusing swirling mass. The Starlings can be just as spectacular when they leave their roost in the morning as thousands of birds erupt out of the reeds all at once.

Mersehead Murmuration. Photo credit: D Jackson (2019).

Keep a look out for birds of prey whilst wondering the trails as two ringtail Hen Harriers have been spotted over the reedbed this week. While males are a pale grey colour, females and young birds are brown with a white rump and a striped tail which give them the name 'ringtail'. They fly with wings held in a shallow 'V', gliding low in search of food, which mainly consists of Meadow Pipits and voles. The participants of our Goose Roost guided walk were delighted to see a Short-Eared Owl gliding across the saltmarsh and our resident Barn Owl has been seen out hunting. Another winter visitor, Merlin has also been recorded.

We completed a reserve count of the wetland bird species on the reserve today. A highlight was definitely the high tide wader roost where eleven species of wader were recorded. Survey results are shown below.

An unexpected visitor in the moth trap at Mersehead last week was a Palpita vitrealis (Olive-tree Pearl). This is a stunning micro moth that comes from the Mediterranean and can often be found in the south of the UK during favourable migrant weather conditions but rarely comes as far as Scotland. It appears to be the 4th record for Dumfries and Galloway. The Garden Moth Scheme came to an end for the 2024 season this morning with Angle Shades, Setaceous Hebrew Character, Streak and Red-Line Quaker recorded. 

Above: Olive-tree Pearl and Below: Angle Shades moth demonstrating how the intricate pattern creates effective camouflage. Photo credit: G. Chambers. 

Rowena Chambers

Our next Forrest School will be on Sunday 24^th November. Booking is essential so please email Mersehead@rspb.org.uk to secure your place. Please note that there will be no Forest School in December. Forrest School aims to cultivate a learning environment in tune with nature, promoting new skills, confidence, self-esteem, and team building while participants take part in fun outdoor activities. 

At Mersehead you will find the RSPB’s only self-catering holiday cottages - Barnacle and Shelduck. Available dates are currently going quickly, so please follow the links to book your next holiday.

 *Flooding - Please note that Mersehead nature reserve is prone to flooding during periods of high rainfall and/or strong winds and tidal surges. To avoid disappointment at these times, please contact the reserve in advance of your visit by email in the first instance at mersehead@rspb.org.uk or check the RSPB Dumfries and Galloway Facebook Page for daily updates.