Nestwatch 2013 - Swallow Nest in Áras an Uachtaráin

Ireland and Climate Change: Are we up for it? Professor John Sweeney - Maynooth University

When the countries of the world assembled for the now famous Rio Earth Summit in 1992 to adopt the United Nations Framework Convention on Climate Change, they undertook to take the necessary steps to prevent ‘dangerous’ climate change. Defining what was dangerous proved a difficult task, however, and largely as a result of the European Union’s prodding, a value of 2oC warming above pre-industrial times was generally adopted as the criterion. Gradually the rest of the world fell into line with this, except the Small Island Developing States of the Indian and Pacific Oceans. For them this was something that would have condemned their island homes to submergence beneath the rising sea. So when the Paris Agreement emerged in 2015, it had a nuanced objective: "to hold increases in global temperatures to well below 2 °C and pursue efforts to limit increase to 1.5 °C." To flesh out what the 1.5oC target would actually mean, the Conference asked the Intergovernmental Panel on Climate Change to produce a Special Report, which they did in October of last year.

The report confirmed that significantly greater climate problems would be experienced at a warming of 1.5oc compared to the present day, even though we have already warmed by 1oC over pre-industrial levels. These would include increases in extremes of heat and heavy rainfall events in several regions, accompanied by more frequent and more intense droughts. But most worrying was the realisation that the remaining carbon budget to avoid this warming would only last for a decade or two at the current rate of greenhouse gas emissions. After this budget was exhausted the carbon would be in the atmosphere for a century or more. Globally, emissions needed to fall by 45% on 2010 levels by 2030. It was this realisation that galvanised many groups and energised many individuals around the world, culminating in the mass protests we see around us. This was true, even in an Ireland whose compliance with its international obligations are failing miserably and its laggard status approaching the level of a national shaming. As a developed country with historical responsibility, we should be bearing more of the burden of tackling this problem than most other countries. Instead our per capita emissions are 50% higher than the EU average and place us as the second worst contributor to climate change on a per capita basis within the EU. The recently released 2018 figures confirm we are now 5M tonnes of greenhouse gas emissions over the limit we agreed solemnly with our EU partners over a decade ago.

At the same time as we declared a climate emergency in Ireland this year we also declared a biodiversity emergency. This was in recognition that Ireland was also experiencing serious threats to its species and habitats, partly due to climate and also a number of other drivers, such as agricultural intensification. Another UN report in spring 2019 confirmed that human actions are now threatening more species with global extinction than ever before. The current rate of species extinction is 10-100 times higher than it has averaged over the past 10 million years. Around 1 million species already face extinction, many within decades.

In Ireland, our peatland, coastal marsh and mountain habitats are particularly at risk. 29 different bird species and 120  species of flowering plants are in serious decline. Some bird species such as the Corn Bunting and Corncock have become extinct. Others such as the Curlew have been decimated and many species such as the pearl mussel, bumblebee, barn owl and marsh fritillary butterfly face serious threats. At the same time invasive species are moving into newly favourable ecological niches providing additional competition and stress to native species.

Ireland has warmed by 0.5oC over the past 30 years and is likely to warm by a similar amount over the next 2-3 decades. This  will have impacts on our growing season, making crops like maize much more feasible to grow. However, projected changes in rainfall are likely to be the main climate change problem Ireland will face. Already we are seeing an increase in intense rainfall events. Increased winter flood problems will result and the government will need to find €1B of taxpayers’ money to protect against future events. Winter storms are also likely to become more problematical. Winter 2013/14 was the stormiest winter in Ireland for at least 143 years. Winter 2015/16 was the wettest winter on record over half of Ireland. Former hurricanes such as Ophelia and Lorenzo pose additional late autumn threats which are likely to increase as the Atlantic warms and summer droughts will bring their own difficulties for agriculture and municipal water supplies. All in all, it is changing weather extremes which will bring the message of climate change home to Irish people and instil in them the urgency of playing a constructive role in international negotiations.

Conscious that it their legacy that is under threat, young people have been in the vanguard of protest. The ‘Fridays for Future’ schools protest has taken up the baton of Greta Thunberg who has become the icon that communicates the reality of climate change more effectively than a hundred graphs and tables. Armed with the factual knowledge of the Green Schools, it is to these inspirational leaders that the rest of society must now turn. The time for tinkering around the edges with excuses about efficiency or identifying ‘low hanging fruit’ on the basis of economic cost benefit curves is now over. The problem is now an ethical one of intergenerational equity, one where scientists can no longer be labelled ‘alarmists’ but rather ‘realists’. In an emergency the unthinkable has to be considered and Ireland is now at a crossroads where the next decade will determine what legacy we leave to the next generation. It’s an awesome responsibility. Are we up for it or not?

Swallow

Hirundo rustica
Fáinleog

Swallow General biology
Length: 20 cm.
Weight: 16-25 grams.
Wingspan: 33 cm.

The arrival of swallows is surely one of the surest signs that summer is on its way. The barn swallow, to give it, its full name, arrives in Ireland in April and will stay till September, before flying back to Africa for the winter. During its brief stay here it will be very active, building up food reserves and raising two, three or maybe even four families in this short time.

We are all familiar with the term; “One swallow doesn’t make a summer”. This old proverb, suggests that caution should be shown during the early part of May. Just because the first swallow has arrived, it does not mean that the weather will stay fine. This year was a classic example. A very good Easter has been followed by a very wet and windy last few weeks.

The swallow is most easily recognized by its long tail streamers and forked tail. The longer a male swallow’s tail streamers are, the more chance it has of mating. This is because the female picks the male with the most symmetrical tails. It is often difficult to see the other distinguishing features because they are almost always flying. They have long, pointed wings and gaping mouths that are used to catch insects when in flight. The head is a bluish colour with a red forehead and also a red throat patch. They have a bluish breast band, but the belly is creamy white. The sexes are very similar, but the female’s tail streamers are shorter than those of the male.

When they first return in early summer, they are very active, feeding on the wing and scooping water from the local river or canal. The males are the first to arrive and they are quick to establish their nest sites. The females arrive later. Some people believed that swallows hibernated for the winter and others even believed that they flew to the Moon!

Swallows have always held a special place in people’s hearts. Apart from heralding in summer, their delightful twittering is a joy to listen to and birds with a blue colouration have always managed to charm us – none more so that the Blue tit. In addition, their effortless movements through the sky is a joy to behold. Indeed, it was considered very bad luck to interfere with swallows. To destroy a nest or to kill a bird would result in continuous rainfall for a month and that cows milk would run dry (in North Yorkshire).

It is often said, that swallows can foretell the weather, just by watching them flying. High flying swallows is a sign of good weather, whereas if they fly close to the ground, it is a sign of rain. There may be some truth to this. Swallows feed on insects. These are more likely to be carried on thermals when the weather is warm and settled. If the weather is unsettled, they will be closer to the ground and hence the swallows will also fly close to the ground.

The name, barn swallow, is well chosen as one of the commonest places to build a nest is within a barn or outhouse. The nest is built of mud and lined with feathers. They gather up little pellets of mud in the beak and use these to form the cup shaped nest.

To strengthen the nest, they push small pieces of grass or straw into the mud walls. Up to 1,000 visits may be made to bring the mudballs to make the nest. Four or five eggs are laid. They are generally white with reddish flecks. These are incubated by the female and hatch after about 15 - 16 days.

The male and female are very aggressive at the nest, chasing off any intruders. The young are fed by both parents for about 21 days, after which they fledge or leave the nest. They can feed their young up to 400 times a day. During cold and wet weather, when insects are not flying, adults may have great difficulty in providing enough food for the young. After the young birds have dispersed, they will be fed by the adults for a few days before they set about rearing a second brood.

Because barns and cow sheds are no longer as common as they once were, swallows are no longer as common as they once were.
As summer draws into autumn, the days get shorter and the weather becomes cooler. This leads to a decrease of insects. Its now time to head back to Africa.

Swallows gather in large groups, often on telephone wires, chattering noisily to each other. Then suddenly, they are gone. The 6,000 mile journey to Africa has begun. Most cross the Mediterranean at Gibraltar, and after a brief rest, all head off again across the Sahara to South Africa. Migration is a hazardous time for the birds.

Many birds will die from starvation and exhaustion.
It’s hard to think that a bird that weighs less than an ounce, can travel thousands of miles every year and bring such joy to us for the summer months. That bird is the swallow.

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