Dalkey Tidy Towns

Wildlife Newsletter for the Township of Dalkey June 2012 - Michael Ryan

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Well done to everyone who took part in the An Taisce National Clean Up on 28th April. Apart from the unsightliness of discarded litter if it ends up in the wrong place it can cause suffering and death to many creatures, particularly plastic when it ends up in the sea as so much of it does. Plastic bags have been found in the stomach of whales and vast amounts of plastic have been found in the stomachs of seabirds accounting for the deaths of thousands of albatrosses and other species. It has long been known that turtles sometimes mistakenly swallow plastic bags resembling jellyfish a favourite food of the turtle and researchers in Queensland, Australia found that marine rubbish was the major cause of sea turtle death.Tiny bits of plastic were found to have perforated the

Fulmars

gut of a turtle hatchling but adult turtles were susceptible to a more painful lingering death due to the structure of their throats which have downward facing spines which prevent them regurgitating. The plastic gets caught in the gut and any food they ingest can’t be swallowed, decomposes and leaks gas in to the turtle’s body cavities causing the turtle to float, eventually starving to death or being left liable to be predated on or hit by a boat.The cliffs below Vico Road hold a bird I often mention, the Fulmar which unfortunately is also very vulnerable to discarded plastic. The Fulmar’s name derives from an Old Norse word meaning ‘Foul Gull’. Fulmars aren’t gulls at all but members of the family of birds that includes Petrels and Shearwaters, their stiff-winged gliding flight, like that of the Albatross, being an adaptation to save energy as they travel vast distances over the sea. The foul part of the name derives from the contents of their stomach which is used by young birds as a defence, vomiting the foul liquid on anything bird, animal or human that approaches them on the nest. Apart from the bad smell this liquid can actually destroy the waterproofing of bird’s plumage ultimately causing their death. Fulmars are one of the longest living birds, individuals over 50 years old are still alive. They don’t breed until over six years old and when they do breed they lay one egg which takes 50 to 54 days to hatch. The chick then isn’t fledged for over 70 days, over three months from when the egg is laid till the chick can fly a very long investment in time and energy.   Fulmars have had a great expansion in their numbers and range since the early 20th century. Until then the nearest breeding colonies were in St Kilda and the Orkneys with most of the population further north in Arctic regions especially Iceland and Greenland. It’s believed they dramatically expanded their range by following whaling ships and in subsequent years trailing trawlers south, getting easy meals from the discarded offal. They feed off the surface of the sea taking crustaceans, squid, fish and carrion and it’s easy enough for them to mistake a bit of floating plastic for a piece of offal. Between 2002 and 2006 in research in the North Sea the stomachs of nearly 1100 beached fulmars was analysed and found to have over 0.1g of plastic in 45 to 60% of the birds.   Fulmars were recorded prospecting nests off Mayo in 1907, began breeding on the cliffs there in 1911 and then rapidly colonised most of our coastline. During the ‘Seabird 2000’ survey, nearly 40,000 nesting sites were counted around Ireland. Ascientific paper, The Fulmar Population of Britain and Ireland, 1959 by James Fisher records them at Killiney in 1958 and interestingly records the species at Sorrento Point and Upper Dalkey Quarry in 1946-1948. Over twenty years ago after a particularly torrential spell of rain Fulmars sat on rocks in the quarry under the Telegraph Tower perhaps after having been washed out of their nests in the wall below the railway line. They didn’t nest in the quarry that time but I was fascinated to see they’d been recorded there previously and on further inquiry I was told by Oscar Merne, one of Ireland’s foremost experts on seabirds, that he remembers them in Dalkey Quarry in the1950s. They can be seen over White Rock beach on the cliffs to the east and sometimes nesting in holes in the supporting wall. They frequently sit on the top of the wall beside the railway line totally indifferent to trains thundering past less then two metres away. Seen up close they have an extraordinary hooked bill made up of oddly mechanical plates. What looks like a telescopic sight on the top of the bill is actually to excrete salt and desalinate them. They have shading around their dark eyes which looks like hastily applied eye shadow but in fact its function is to act like sunglasses, reducing glare when they’re feeding from glistening waters.

Greenfinch

I was wondering was a very determined grey squirrel to blame for the rapid emptying of my sunflower seed feeders during May, a month when the birds should be finding abundance of food in the wild. Our most consistent visitors to the feeders are bullfinches with up to three pairs coming to the feeders regularly.   They get through a lot of the seed but at this time of year they can be seen feeding on flower buds and dandelions which we can provide for them in abundance. So I was glad to see that the seeds were disappearing not into a squirrel but into eight greenfinches crowded on to the feeders. We hardly get any now in the winter and greenfinches have declined by up to 33% in some areas but they do seem to be regular summer visitors to our feeders and   I’m always glad to see them.

Unfortunately, greenfinches are particularly susceptible to a parasite borne disease called trichomoniasis which causes the birds throat to swell making it unable to swallow food. Many people have reported sick greenfinches in their gardens in recent years. The birds will be lethargic showing none of their usual alertness sometimes with feathers fluffed up and may be drooling or regurgitating food. The disease is caused by a parasite which can’t live long outside the host but keeping clean feeders, bird baths and other surfaces that the birds might feed from can significantly help reduce the chance of the disease spreading. Trichomoniasis can’t be caught by humans. Our visiting greenfinches looked healthy but like any good restaurant I’ll prioritise hygiene standards for the benefit of my visiting diners.