Portmarnock dune system depends for it’s survival on a balance between the natural forces of wind and sea which can both build and erode the dunes. Human activity is a third factor which left unchecked can destroy the dunes by trampling, fire or building development.
Sand dunes are a very limited resource taking up only 0.2% of the country’s land surface yet the recreational attraction of beach and dunes is immense. Dunes start to grow when blown sand is trapped by the line of flotsam and jetsam at the back of the beach forming little sandy mounds which are colonised by special pioneer plants that can tolerate the shifting sand and salt sea spray.
These plants trap more blown sand and as hummocks grow, the great dune builder, Marram grass comes into it’s own. It is that prickly grass that is so characteristic of dune areas. It grows best in blowing sand, sending out new shoots and roots that bind the sand and build sand ridges. When blown sand no longer reaches the ridges because of new dunes forming on the shore, the Marram grass grows less strongly and other plants start to flourish. A short dry flowery grassland forms inland behind the ridges and a different group of moisture loving plants occur in the lower lying wetter lands, called dune slacks.
Portmarnock peninsula has a rich dune flora, with over 250 species including some of Irelands rarer plants. The dune flora is especially rich because of the light warm soil conditions. Dunes on our east and south coasts have a greater number of species than those on the west and north coasts where the climate is colder and wetter. The Fingal coastline is also the most northerly outpost for a number of plants that grow in Ireland.
Among the typical plants of dry dune grassland are nitrogen fixing clovers and vetches including Bird’s foot trefoil and Kidney vetch. Other typical species are the purple and yellow violets and pansies and the creamy white Burnet Rose. Among the most spectacular of plants are the Orchids. The Bee Orchid occurs in dry dune grassland whereas the more plentiful pink and purple orchids are found in wetter areas.
One of Irelands most threatened plants is now only found on islands within the Portmarnock Hotel Golf Club. This delicate plant and it’s habitat are protected under the Wildlife Act (1976). In addition a further twelve species found on the peninsula are of special interest because they are rare on the east coast or in Ireland as a whole. The future survival of such plants is under threat because of continuing loss of habitat caused by such factors as development pressure, heavy recreational use, overgrazing and modern agricultural practices such as drainage schemes and use of fertilizers. (development of golf courses.)
There is a large variety of those animals without backbones ( invertebrates) here including beetles, bugs, bees, butterflies and moths. This is due to the abundance of their preferred food and the dry warm conditions in the dunes. The Burnet Moth is perhaps the most noticeable insect around mid summer. It’s wings have a black metallic sheen boldly marked with red spots. Nine types of butterfly occur. Different species prefer different food plants. You will find the caterpillar of the Common Blue grazing on vetches and trefoil, while that of the Dark Green Fritillary prefer the Dog Violet. The invertebrates, in their turn, are food of the birds and small mammals of the area.
The mammals found on the peninsula are generally shy creatures that can move fast and hide long before you can catch up with them. You will need patience to wait and watch at quiet times. There is not a lot of cover in this open landscape and you can expect to see some interesting mammal species. Among the smaller mammals are mice, shrews and hedgehogs., while larger mammals you may see include rabbits, hares, foxes and badgers. If you keep a keen lookout you may be lucky to see seals off the Velvet Strand and Portmarnock Point.
Portmarnock is an important area for wild birds. There are 120 bird species that maybe seen in the area of Portmarnock peninsula.
Portmarnock Point is a particularly important feeding and roosting area for a range of birds because food is plentiful and the Point is remote from disturbance. The roseate tern, an internationally rare bird that overwinters in Africa has recently been recorded on the Velvet Strand ad at Portmarnock Point.The Little tern, a rare breeder in Ireland, nests at the Point. Both the Little Tern and Ringed Plover provide excellent examples of camouflage.
Baldoyle estuary is a nature reserve to conserve its marine ecosystem because of it’s international importance as a winter habitat for Brent Geese. These geese nest in Arctic Canada and migrate to Ireland to spend the winter here. You can see these geese feeding in the estuary and also in the gold course and green across from the petrol station. There are several white egrets now in the estuary. The Kingfisher is one of the more exotic birds that you can see along the estuary. It is unmistakable as it dashes past in a flash of bright blue.