Survey Walk to Dunollie (NM8531) – Tuesday 29th December 2009

We parked on the sea-front road towards Ganavan just before the War Memorial at (NM852309).  Waiting for other members to arrive, we looked over the railings and apart from two Mute Swans and an Oystercatcher found three Turnstone searching for invertebrates amongst the rocks and seaweed  Indeed, that is how this industrious wader gets its name, a perennial winter visitor to the shores around Oban, arriving from Greenland or possibly Arctic Canada.  These birds are remarkably tame due the fact that their breeding grounds are normally far from human habitation.  They can be seen in flocks of around thirty in Oban, sometimes feeding within several yards of pedestrians passing by on George Street.

  

As we walked towards Dunollie Castle the views to our left took in the northern tip of Kerrera and beyond to the snow covered hills of Mull, an awesome sight.  Within a hundred yards we followed a track off to our right leading away from the road, amongst deciduous woodland. The usual woodland birds were to be found here including Blackbird, Song Thrush, Robin, Dunnock, Great Tit, Blue Tit and Wren.

 

The next feature to greet us on our left was a huge mound of rock topped by several conifer trees. This rock was formed in the Devonian period some 350 to 400 million years ago, when Scotland was nearer the equator than it is today. The deposition of sedimentary rocks washed down desert valleys (wadis) during flooding, into sediment-rich shallow seas, formed what is known as a wadi conglomerate.  Also not to be ignored is Dunollie Castle, a stone 13th century keep and courtyard fortress, built on an old site of the Kings of Dalriada. In the 15th century, a four storey keep was built on to the castle enclosure.

  

Walking along the track we found mature Beech and Oak trees with some of the expected species of Lichens shown above, Lobaria pulmonaria (Tree Lungwort)  and Lobaria virens (Green Satin Lichen). It was good to see these along a popular walking route so near to the town centre. Also observed were Degelia atlantica (Felt Lichen) and Parmotrema crinitum (Desperate Dan!).  Altogether we recorded a good number of species indicating how pollution-free this area of Lorn is, so close to Oban.

More unexpectedly we found Pertusaria Amara (Bitter Wart Lichen) and a fungi, Hypoxylon fragiforme (Beech Woodwart) growing on a dead piece of Beech shown below.

 

At the end of the track we turned right through a gate and continued alongside the woodland and to our surprise a Red Squirrel was spotted on a mossy bank inside the wood. Continuing our search for Lichens another expected find was Sticta limbata (Floury sticta) on a tree close to the track.  There were several trees with wind damage, attesting to the severe winds experienced on this west coast.

Turning left now and wandering into another section of woodland we discovered what for me was the  highlight of the day, two groups of three ladybirds hibernating on a tree trunk. All insects in cold places like Scotland need to find a way of coping with winter, when not only is it cold but there is less around to eat.  Adult ladybirds do this by hibernating.  In this state they can withstand sub-zero temperatures.  They go into suspended animation, their bodies do not develop, they do not eat or move; and must rely on their stored body fat to sustain them until spring.  Their bodily processes slow right down to a 20th of their normal active rate, which helps the body fat last longer.

Close by we discovered some Ganoderma australe (Southern Bracket fungus) on some decaying tree trunks. . Other common fungi recorded were Trametes versicolor (Turkey tails), Stereum hirsutum (Hairy Curtain Crust) and Xylaria hypoxylon (Candlesnuff fungus).

 

The fungi attack dead wood and rot parts, which means a huge increase in insect life, which in turn is food for birds and also results in the trees having lots of holes and soft areas for birds to nest.  In a truly natural wood there is a huge amount of dead and rotting timber compared to live healthy trees. Another fascinating discovery was this bird’s nest, sheltered below some bracket fungus, home sweet home !

As we returned down the track to the road a pair of Redwing and a Song Thrush were rooting amongst the grass and leaves looking for food on this desperately cold day.

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