Marsh Harrier Returns to the Wetlands

Word spread quickly last week that a rare visitor was spending a day at Cabragh Wetlands. The Eurasian marsh harrier was once a very familiar sight in Ireland and Britain, with the Victorian folk lore writer Charles Swainson reporting an old story that considerable numbers of harriers would land on the Wiltshire downs before heavy rain. Victorian hunters, egg and skin collectors raided nests and shot them out of the sky. Agro-chemicals and drainage of fenland habitat caused more problems, with organochloride pesticides wrecking attempts to re-establish numbers in the 1950’s and 60’s. By the 1970’s there was just one breeding pair in the west of Britain and one at the great Suffolk nature reserve at Minsmere, which is perfect harrier reedbed habitat. Many books published before the end of the millennium did not even record the marsh harrier as a resident of or visitor to Ireland.



Reduction in chemical use allowed numbers to grow at about 20% per year, and by 2000 there were 206 breeeding females spread from Kent to the Orkneys, with individuals crossing the Irish Sea. With luck a success story is developing.



Marsh harriers are the biggest and heaviest of the harriers, with the male about 50cm long and the female larger. She has a brown body and wings with a pale yellowish head, throat and forewing. It was a male that visited Cabragh, magnificently photographed by Eamonn Brennan, who captured its pale body, head and wings as it spent some time investigating our owl box atop a telephone pole. Most impressive were the great reddish-brown shadings on his wings. Old Irish names include Duck Hawk and Snipe Hawk, which reflect the lifestyle of the marsh harrier as he glides over reedbeds and wetlands searching for prey.



The marsh harrier is not a fast-flying hunter. In fact he is master of slow flight, gliding silently over reedbeds at barely 10mph, giving himself every chance to spot mice, frogs, reptiles, eggs, nestlings and rodents that make up its varied diet. Like the owl, marsh harriers have keen hearing, with facial feathers hiding large ear openings which help it to funnel sound and improve ability to detect prey in thick reedbeds. Nests are a mass of reeds and willow twigs, lined with grass and containing four or five eggs, which the female incubates for 36 days, with the male feeding them for another 40 before the young fly. Resident harriers spend winters in communal roosts on wetland sites.



It was a real pleasure to have a migratory marsh harrier at Cabragh for a day. Perhaps they will nest here in the future, though our ducks, snipe, frogs and mice will have to be on their guard.

Swallows

All members of Cabragh Wetlands Trust are reminded that the AGM will take place at the Wetlands Centre this coming Tuesday, May 4th, starting promptly at 8.00pm. As always, this is a very important time for communication between the Committee and the membership, and as a local community-based organization, the Trust welcomes the chance to update members on the plans to renovate the Centre and the ever-growing education programme, as well as our core work of conservation of habitat and bio-diversity.



With spring well on the way, the rain over the weekend was very welcome, easing the task of digging the vegetable patch and watering the new crops. Gardeners at the newly inaugurated Cabragh organic allotments have been out in force preparing the ground for their first growing season. The sight of swallows arriving has certainly gladdened the hearts of many of us – is there a more graceful sight in nature than the gliding-swooping flight of the swallow? One almost feels that telegraph wires were made for them to sit and survey the world beneath.



After wintering in southern Africa, the swallows have flown 6,000 miles or more to return to their breeding grounds. Most adults will go to the same locality year after year, so you really are welcoming back old friends. They tend to build their nests on ledges on top of walls or against roof beams, and may well use exactly the same nest for many years, upgrading it with fresh mud and straw so that it is secured with architectural precision. Ornithologists conclude that swallows were originally cave nesters, and began to move to man-made structures when human construction began in the Tigris-Euphrates valleys some 10,000 years ago. They love to nest under bridges, recreating their ancestral caving instinct, and nests have been found several metres underground in old mine shafts. Last week Kevin Collins showed us a remarkable picture of a swallow’s nest at his house that contained 17 tiny wrens, crammed into it for shelter on one of the coldest nights of the recent freezing winter.



Swallows play a major role in keeping insect populations under control, catching them in flight. Often they live around busy farms and are known to follow farm machinery, no doubt because the activity will disturb insects like aphids, flies and bluebottles, driving them into the air for the swallows to seize. Their natural habitat is that invisible space hanging over the earth up to about 500 feet in height; as they fly lower than house martins and swifts, swallows are more susceptible to pollution and pesticides and are consequently declining in numbers compared to their close cousins. They will often drink on the wing, gliding open-beaked over a pond and swooping low to scoop up a mouthful of refreshment. In late summer and autumn places like Cabragh Wetlands provide reedbed roosts where hundreds of swallows may gather before migrating in mid-September.



The good news is that Ireland’s population of swallows is holding up better than most, largely because of the relatively low use of pesticides and the preservation of a lot of ruined buildings. One man’s ruin is someone else’s niche habitat.

Starlings

At Cabragh Wetlands we love the autumnal appearances of those huge flocks of hundreds of thousands of starlings, which swirl and sweep across the evening sky in massive grey-black clouds before settling into the reedbeds to roost for the night. But at this time of year we see a different side of this little fellow, as they busily set about nesting and breeding.



They love to build their nests in the eaves of our houses, landing on the guttering and finding gaps up into the roof space through which they can squeeze. For weeks now our garden has been festooned with little yellow tufts of soft material, like cotton wool. This is (or was) our precious roof insulation, dragged out and casually tossed away by the fussy starlings, who work very hard to clear out unwanted debris and create a nest as soft and clean as they can manage. A few days ago a skeleton appeared on the lawn, the dessicated remains of one of last year’s brood that did not survive infancy. Thrown out of the nest to create space for the class of 2010 and stripped of everything unpleasant, the bones now make an interesting exhibit for children to study on visits to Cabragh.



With its speckled feathers glinting in the sun, the starling is a truly beautiful bird. In summer and autumn a purple plumage on the chest makes him even more impressive, especially if you can put up with the noise. Almost from hatching they hold forth with a variety of indescribable noises, clicking, gurgling and whistling but never managing the mellifluous sounds of the blackbird or thrush. They are also great mimics, not least of human sounds. They have been known to imitate cats, frogs, owls and chickens; at least one dog has been driven mad as it dutifully tried to respond to its owner’s whistle, and people have rushed indoors to answer phones that weren’t ringing. Nowadays mobile ring tones are a favourite. Mozart’s pet starling is supposed to have inspired his G-major Piano Concerto, and certainly Mozart and the starling share a reputation for being brash, aggressive and generally obnoxious.



They are considered dirty and unhealthy (she-who-has-to-clean-the-windows would agree), but are good friends of sheep, pecking off ovine ticks in their fleece. The sites where they roost in the autumn can be devastated, vegetation broken down and killed by acidic guano from vast numbers of individuals answering the call of nature; in such death and decay mould and fungi flourish. Introduced to North America in the 1890’s, they are regarded there as a serious and invasive pest, with millions of dollars spent trying to eradicate them from Alaska to Mexico. In contrast the Russians love them, seeing them as a friend of the farmer (think of the number of insects a large flock will eat) and the harbinger of spring. Under the communists, the state provided 22.5 million nestboxes to encourage starlings, with children given school projects to record their usage.



The collective noun for a flock of starlings is a “murmuration”, which memorably evokes the sweeping rhythm of a million starlings on the wing, but certainly not the raucous cacophony coming from our roof spaces at this time of year.

Frogs

A year ago the papers were publishing alarming stories about the plight of the world’s frog populations, reporting that many species were under threat and not producing enough healthy young to guarantee their long term viability. That may still be the case, but it is great to report that here at Cabragh Wetlands our frogs seem to be in very robust and noisy good health.



Our artist-in-residence, Eamonn Brennan, has produced more wonderful pictures of frogs doing what comes naturally in late March as the weather warms up and spring gets underway. The females are laying huge quantities of eggs, and the males are busy fertilizing them at extraordinary rates – up to 4,000 each. Areas of the wetlands are alive with small bodies piled on top of each other, with pools of frogspawn spreading around. The air is filled with a cacophony of croaking as the males try to find a female partner.



This of course is one the best known signs of spring, and most of us will remember as children collecting frogspawn in a jam jar and studying the life-cycle of the frog by watching the eggs turn into wriggly tadpoles. It can almost be seen as one of those childhood rites of passage, an event which takes us out of the narrow cocoon of the family and introduces us to the wonder, beauty and variety of the natural world. How many of you remember that the frog begins as a fish-like creature, breathing through gills in its tadpole stage, before growing a tail and legs? In an amazing transformation it then abandons its gills by growing lungs and breathing like a land-based animal before emerging tailless as a fully mature frog.



Here at Cabragh Wetlands we are in a great position to give children the chance to study this sort of process at first hand, rather than from an indoor textbook lesson, computer screen or newspaper article. Children will love learning out in the middle of nature. If you can, get in touch and arrange a visit for your school or group. We can be contacted on 050443879 (mornings) or via e-mail at cabraghwetlands@eircom.net. Give the kids a chance to experience those tadpoles and frogs in their natural environment.

Furze

There is a fresh feeling to the countryside this week. Much needed rain is putting a touch of green back into the yellow-brown grass and the daffodils are beginning to open out, giving a wonderful golden-yellow display in our gardens to supplement the still-flowering remnants of snowdrops and crocus. Spring is here. Of all the plants of spring, my own favourite is one that barely gets a mention in most gardening and flower books – the spiky furze, or gorse.



We cultivate broom, its less dangerous cousin, which fits nicely into any sizeable country garden as well as colonizing wild areas, but you can be sure there would be vociferous objections from many in the family if you tried to introduce clumps of furze with its long branches covered in sharp-spined thorns. So the poor old furze tends to be an outcast, left on the edge of civilization, flourishing only in wild heathland, open grassy areas high up in hill country with only a few sheep and cattle for company. But what a magnificent display it provides at this time of year. As the road from Thurles to Nenagh climbs higher, the landscape from the Devil’s Bit across to the hills beyond Templederry is ablaze in a fiery yellow swathe as the furze flowers in its wild beauty.



It makes wonderful cover for wildlife. Canoeing on a lake one day, we enjoyed great views of a fleeing fox with hounds and huntsmen in close pursuit. Large patches of furze sprouted across the open moorland; the fox ducked into one for a few minutes’ rest, and then slipped unseen to the next while the dogs gathered on the perimeter of the first, apparently intimidated by the ferocity of the bristling spikes on the furze. For the best part of an hour the fox toyed with its pursuers, who could never quite pin down where it was hiding (we were not going to tell them) as it moved from cover to cover before eventually escaping to live another day.



Furze is a reminder of the natural wildness in the environment, helping us remember that our cultivated farms and gardens are all unnatural creations of the last few thousand years, and that the plants we grow for food and beauty are almost all bred by man from original species that slowly evolved over countless millennia.

Linnaeus the great Swedish naturalist visited Britain in the 1730’s and is supposed to have fallen on his knees and given thanks to God when he saw his first furze-covered common, so overcome was he by the sheer beauty of the scene.



So enjoy the furze, which will flower for most of the year and will give the bees an early source of pollen. If you make your own wine, gather its flowers and you will find it makes a wonderful, fragrant dry white. Use the plant to reconnect with untamed nature. Walk around Cabragh Wetlands and you will find a number of bushes; note that the flowers grow from leaf nodes and smell of cocnut. And you may enjoy putting that wonderful old saying to the test – “When furze is in blossom, kissing’s in season”.

A Lecture on Soil

Cabragh Wetlands is getting down to the basics at its next evening talk on Tuesday 23rd March starting at 8.00pm. The speaker is Stella Coffey, an organic farmer from Cahir; she has a BSc in Biological Sciences and her subject is “The Wonder of Soil”. This is a topic that most people will recognise as being of prime importance, especially for those interested in the quality of the food they put on the family table and in sustaining healthy biodiversity. Stella has one of the oldest organically certified herds (of Aberdeen Angus cattle) in the country. If you value the health of your garden, are starting out on a new allotment, enjoy the fruits of the Farmers’ Market or are concerned about the state of farming and use of chemicals on the land, then this is a key evening for you to attend. All are welcome and entry is free.



At the heart of any consideration about the health of our soil is that most undervalued of creatures, the humble earthworm. Though surrounded at home and Cabragh by books on wildlife, it is alarming that so many contain no indexed references to this crucial little fellow. The normal public reaction to a wriggly worm is almost invariably one of disgust, and total failure to recognize the key role played by worms in the development of life on earth. The sprawling compost heaps in my garden are a constant source of fascination. They act as breeding grounds for worms, which live in their thousands, eating their way through remains of plants and other biodegradables thrown on the heap. Material passes through the body of the worm, is cast out and gradually transformed by the action of bacteria into humus, that essential ingredient of fertile soil.



In a day a single worm will eat about a third of its bodyweight, well under a teaspoonful. Insignificant on one level, but on another perhaps the most important day-to-day activity on the planet. Every ounce of organic vegetable mould has passed through the body of worms many, many times. Worms alter the composition of the soil, improving its ability to absorb and contain moisture, changing the balance of microorganisms and nutrients. Through these processes they determine the ability of soil to grow particular kinds of plants, thus playing a key role in deciding which plants grow above the surface of the earth, and in turn influencing the type of insects, mammals and birds that can evolve and live in any area.



The worm moves through the ground, eating tiny particles of decaying organic material, which it ingests with a few grains of clay, creating a permanent burrow. At night it comes to the surface, leaves a few milligrams of castings and then searches for new material (leaves, grass, anything organic) to drag underground and break up. As well as acting as a miniscule plough, worms will, piece by tiny piece, shape the landscape above the surface, burying items left on the ground. That key you dropped, those stones you flung in a corner of the garden, that path you laid, all will be buried by the action of worms. Given enough time and enough worms, collapsed houses, towns and whole civilizations will disappear under the ground. Is it an illusion that things sink below the surface? Surely worms are causing the level of the surface to rise? Archaeologists having to dig down several feet to find their lost treasures are surely clear evidence of the unlimited power of the humble earthworm to shape the landscape above.



Charles Darwin spent his last years studying and writing about worms. This most humble of creatures has a strong case to be considered the most important and indispensable creature on the planet. There can be no doubt that it plays a far more important role in sustaining life on earth than humans. Come to Cabragh Wetlands on Tuesday 23rd to reflect more on “The Wonder of Soil”.

Biofuels

As part of a vast raft of ideas to reduce carbon emissions and greenhouse gases, stop global warming and save whatever we can of the huge range of life on earth, the European Community is legally committed to ensuring that a steadily increasing proportion of petrol and diesel used in road transport is sourced from renewable sources. This will mean more electric vehicles, but most (it is anticipated) will come from plant-based bio-fuels, including soy, sugarcane, rapeseed and palm oil. The advantage of plants grown for fuel is that they are renewable year-by-year, and that each litre of green biofuel burnt will reduce carbon emissions by 35% compared with a litre of traditional fossil fuel (coal, oil).



This sounds wonderful, but inevitably problems are emerging. The fuel-crops mentioned above are mostly tropical plants, and palm oil (apparently the most efficient for biofuels) can only be grown in regions like Indonesia and south-east Asia, west Africa, Brazil and the Amazon rain forest. To grow crops for biofuels to reduce greenhouse emissions, rainforests are being cut down at a frightening rate – rainforests which soak up carbon dioxide emissions as they grow. To meet desirable emission targets in Ireland, Britain and the EU, millions of acres of pristine forest are being logged, burned and converted to palm oil plantations. In Indonesia alone an area the size of Wales is being deforested every year. The orang-utan, one of our closest relatives, has been driven to the verge of extinction in Sumatra, and the survival of many tropical species of plants, insects, animals and birds is in doubt, including species only recently discovered – and probably others that we have yet to find and study.



We are now at the stage when studies are emerging which suggest that it is better to burn oil in your car than green biofuel, because of the environmental cost of producing palm oil, which is directly causing an acceleration of the loss of rainforest habitat. Burning rainforest releases greenhouse gases and reduces Earth’s natural ability to soak up carbon dioxide. A Danish study says that it would take 75-93 years for the benefits to the climate created by switching from fossil to biofuels outweigh the terrible damage caused by converting tropical forest to palm oil plantations. Apparently it will take 840 years for a palm oil plantation to soak up the carbon emitted from trees and soil by clearing forest to plant the crop.



This is a problem of horrible complexity. What is becoming clear is that palm oil is not likely to be a magical solution, despite massive lobbying by the multi-billion dollar business. Needless to say there is also evidence of corruption, violence and trampling on the rights of indigenous peoples. Can we ask those who are experts on these issues to share their expertise and perspectives with the general public? Are there crops that could be grown for fuel in the Irish climate? Certainly our farmers seem to open to chances to diversify with traditional agriculture struggling at the moment.