RSPB Scotland Research Assistant, Davide Scridel, is out searching for an elusive bird in the Outer Hebrides. Find out more about his experiences and check out his fantastic photos below!
Island living: searching for twite in the Hebrides
The subject of the 2013 Statutory Conservation Agency/RSPB Annual Breeding Bird Scheme is the twite! The first survey, in 1999, produced a population estimate of 10,000 pairs with the majority of the breeding birds located in Scotland, then England and only a few pairs remaining in Wales. Due to the severe decline that this species experienced since the 1800s, twite are of the highest conservation concern in the UK. It is therefore vital we to reassess its population trends fourteen years after the previous national survey.
Twite perched on rock by Davide Scridel
Twite breed on unenclosed moorlands, hills coast and islands especially near farmland, with nests occurring on heather moor, sea cliffs, in gorse and, more rarely, in conifer plantation. They primarily feed on seeds found in grassland and cultivated habitats such as pasture, meadows and young fallows.
In Scotland twite breed most commonly in the Western and Northern Isles, in the Inner Hebrides and along the coast of West & North Scotland where these habitats are particularly widespread.
I feel very privileged because I have been assigned to survey this understudied species within a series of randomly selected 1x1 km2 in the Outer Hebrides (Uist, Harris & Lewis), some of of my all-time favourite places. These islands are extremely beautiful and are the stronghold for breeding twite in the UK. Such preferences can be partially explained by the fact that the islands offer coastal and moorland habitats as well as the unique, small-scale farming practice called crofting.
Here fields are low-intensively managed to produce cereals or foraging grasses for livestock and the interaction of these human activities and the natural occurrence of a unique calcareous landmark Machair, formed by windblown shell sand, provide enough fertility to support cereal-based livestock production.
This is particularly true in the island of Uist, where I am based. Here cereals are grown using limited pesticides and low fertilizers with fields left fallow traditionally on a biannual basis, allowing very rare plants but also ruderal plants, such as dandelion and common sorrel, to emerge. These are the twite’s absolute favourites and part of our task here is to record the presence of this species also in relation to the amount of flowers we can see in the surroundings.
Golden plover on freshly ploughed machair by Davide Scridel
Small scale-low intensive agriculture practises are very rare nowadays and only persist in isolated areas but they are truly a heaven for orchids, invertebrates and for rare and declining farmland birds such as corncrake and corn buntings. Twite are much more than just “brown” birds. They are true indicators for changes in the way we live and how our needs affect our landscape. It is therefore very important to assess how the twite population is responding to human and non-human changes fourteen years after the previous survey.
08/05/2013
It is now a week since I took the ferry from Uig (Skye) to reach North Uist. The journey was remarkable: surreal landscapes and plenty of wildlife, with highlights such as golden and white-tailed eagle and hundreds of razorbills floating around a motionless sea. It was so unbelievably still that even the boat crew were capturing it with their cameras while approaching the Outer Hebrides - such rare moment for this part of the world.
Lochmaddy at dusk by Davide Scridel
I spent the following two days meeting local RSPB colleagues working on the site as well as partners SNH and MACHAIR LIFE+. The latter organisation is of particular interest to me as they are truly dedicated people, with the focus of increasing awareness and protection for this rare habitat full of biodiversity and very important not only for twite but also for rare invertebrates such as the Great yellow bumblebee, confined to a few spots in the whole of Britain.
The first day of the survey involved visiting a 1x1 km2 located in South Uist. We didn’t see any twite but spotted stonechats, ravens, kestrel, whimbrel, wheatear and plenty of meadow pipits amongst others. An excellent introduction to the Western Island wildlife! But things got even more exciting towards the last transect when I noticed in the far distance a female hen harrier emerging from a spot in thick heather while whistling piih-eh to an approaching food delivering male. That made my day...and it was only the first one I’ve seen in the field. After seeing the female returning to the same spot I was then sure I had found a nest and decided to walk off immediately to avoid potential disturbance to the breeding pair.
Stonechat by Davide Scridel
Despite such excitement, I was quite disappointed to have not seen any twite. The weather forecast for the following day was typically Hebridean- rain and winds up to 40 mph which suggested a boring day indoors. Suddenly, those strong winds that brought rain in the morning also cleared away the cloudy sky and a splendid, but still windy afternoon, allowed a visit to a second square.
Similar to the first one, this square incorporated a combination of moorland/coastal habitat and after a few transects and point counts I detected the unmistakable “twit” and a later rambling song or “chortle”. Five TWITE amongst two pied wagtail and a few meadow pipits were confidently feeding on a white sandy beach energetically seeking for seeds amongst the washed up seaweed.
Twite searching for seed by Davide Scridel
No rings on legs but 4 out of the5 birds showed clear signs of pairing. The “chortle” is in fact a reliable indicator of breeding activity and my excitement did not stop when two birds decided to leave the feeding spot and fly towards the grass/moor mosaic cliff less than 100m away from the beach.
One of the birds remained perched on a stone, guarding the mate disappearing into a small crevice. I decided to wait and visit that crevice when both birds went back to feed on the shore. There was a nest there, carefully lined with grass and some sheep’s wool at the bottom of the cup. It was my first ever twite nest containing three light blue eggs with tiny black marks. I left the site quietly and checked for the safe return of the incubating female. It was a confirmed breeding site for twite and a very exciting day for me!
Male twite by Davide Scridel