RSPB Mersehead Recent Sightings 21st – 27th November 2020
It’s definitely feeling more like winter this week, with frosty mornings and the bright sun lending a magical quality to the reserve. As the work day starts with the sunrise, the low light captures Roe Deer and Hare in their morning routines. During the gorgeously sunny weekend, before the rain came, a dozen Fieldfare were seen high up in the woodland, enjoying the morning rays. Unlike Blackbirds and other Thrushes which stay hidden in hedges and undergrowth, Fieldfare gather on high branches and will roost communally, often flocking with Redwing. Fieldfare are mostly found in rural areas, although in very harsh winter conditions they can be seen sheltering in gardens.
Fieldfare. Photo credit: B.Taylor
The hedgerows have been bustling with activity, including sightings of Gold Finches, Blue Tits, Great Tits and Yellow Hammers through the week. As only a very few leaves are still clinging to the trees, these species are easier to spot, feasting on Hawthorn berries. Don’t miss the opportunity to sit a while in the hides where Gadwall and Tufted Ducks (a personal favourite!) have been seen this week. Gadwalls are an exciting spot at Mersehead as they don’t winter here in large numbers. Gadwalls are dabbling ducks, feeding on vegetation near the surface of the water. To be in with a good chance of seeing them, look around the shallow edges of the pools. A tip for identifying them is to watch them while they feed. The Gadwall technique is to ‘upend’, with the males exposing their characteristic black rear.
Blue Tit. Photo credit: B.Taylor
Gadwall. Photo credit: Ben Andrew (rspb-images.com)
Through the wind and rain, the waders have been out on the mudflats searching for food. The Solway Firth provides a key habitat for estuarine waders including Redshank, Knot, Curlew, Grey Plover and Ringed Plover. The non-breeding winter season sees huge flocks gathering along the estuary, making them a conspicuous and mesmerising bird group to spot. The intertidal mudflats are an essential habitat; providing the wealth of nutrients required to meet their extremely high daily energetic demands.
The wader diet mainly consists of invertebrates buried in the sand and mud, namely bivalves, mudsnails (gastropods), worms and crustaceans. This means that a walk along the Mersehead coastline provides evidence of the whole food chain, as the sand is covered with hundreds of bivalve and gastropod shells. These shells provide protection from dehydration and mechanical damage, and also give support for the soft body within.
Bivalve shells are made of twin shells joined by a hinge, although this often breaks so the shells you find are one half of a whole. The Baltic Tellin is a common bivalve in estuaries as it is tolerant of saltwater. The shells of these molluscs vary in colour, commonly a beautiful array of pinks, yellows and whites.
Baltic Tellin. Photo credit: B.Taylor
Gastropod shells are usually whorled, although the limpet is an exception. Limpets are made up of an extremely strong cone shaped shell and a soft body within called a ‘foot’. When the tide is out, the foot is used to attach to a surface, preventing the soft body drying out. When the tide is in, they use their foot to move across the surface very slowly, feeding on microscopic life.
A Barnacle hitching a ride on a Common Whelk. Photo credit: B.Taylor
The feeding habits and routines of waders are governed by the tide movements, limiting the available time for foraging. The different physical adaptations and foraging strategies which each species has developed increase the area over which waders feed and reduce competition between species. These specific habits also make them easier to identify, something I greatly appreciate as I get to grips with surveying large flocks!
The large eyes of Plovers enable them to hunt during nocturnal low tides. Their characteristic running forward, feeding, stopping and looking again enables them to quickly grab their meal with their short beak.
Mollusc-eaters, including Knot, have strong stomach muscles allowing them to crush the hard shells of Molluscs such as Cockles. Cockles are very common on the Solway, living in the top few centimetres of sediment and actively feeding on plankton and other sediment floating in the water. Similar to trees, by counting the radiating rings on the Cockle shell it is possible to estimate its age.
Common Cockle. Photo credit: B.Taylor
Knot. Photo credit: Andy Hay (rspb-images.com)
The Curlew is the largest wader and uses its distinctive long, curved bill to reach further into the sediment, finding worms and beetles. When the mudflats are inaccessible at high tide, the Curlew is one of many waders which can supplement their diet in the grass fields, where they share their habitat with the thousands of wintering Svalbard Barnacle Geese. Listen out for its haunting call as it travels from shore to field.
Curlew. Photo credit: Andy Hay (rspb-images.com)
The evenings are continuing to play host to the fantastic murmurations. Don’t miss the opportunity to watch the sky as it’s filled with Starlings swooping and soaring overhead. To enable you to enjoy this in a covid-19 safe way, we ask that you avoid using the hides, and follow directions along the tracks.
I have had the most wonderful introduction both to the team and reserve work. I feel extremely lucky to be here as a residential volunteer, with already 8 fantastic weeks of immersion in reserve life.
Have a great week,
Beth Taylor, Residential Volunteer