Anja Murray: Spring migration is tough enough — here's how we can help

Swallows, with their distinctive long tail streamers, come all the way from wintering grounds in southern Africa and most of the Irish nesting birds will arrive in April, returning to the very same barn where they were born. Across the northern hemisphere, tradition has it that swallows bring good fortune to those who have them nesting in or near their home.

Cuckoos arrive back in the last days of April and into the beginning of May, causing great excitement up and down the country when the first calls are heard. Cuckoos, however, are arriving back in much reduced numbers these days — a decline attributed to the changing nature of Irish farm fields, a result of the intensification of agriculture. They eat only hairy caterpillars, which are negatively impacted by the loss of semi-natural habitat across the Irish countryside.

To better understand their migration, Irish ornithologists from the National Parks and Wildlife Service, working in association with the British Trust for Ornithology, have been fitting cuckoos with satellite tags in recent years.

One of the revelations about the cuckoo's migration routes was that some make significant detours along the way in order to find suitable caterpillar-rich habitats. Several of the tagged birds struggled to cross the Sahara desert, which is expanding due to climate change. They were also adversely impacted by severe spring droughts in countries such as Spain, Italy and Greece, which make it increasingly difficult for the cuckoos to find sufficient food to sustain them on their journey.

These findings are consistent with a new study just published by the Hellenic Ornithological Society (BirdLife Greece), which collated evidence of how climate change is rapidly making the treacherous journey of migratory birds even more deadly. The Sahara Desert presents one of the toughest challenges, being a vast, arid expanse where survival depends on reaching the few scattered oases and vegetated areas for rest and refuelling. But these oases are drying up and shrinking, removing essential stopover points for spring migrants returning to Europe. The study also describes how Mediterranean regions are becoming increasingly inhospitable with prolonged droughts and wildfires ‘creating unprecedented challenges for their existence’.

A sliver of hope is presented, with major conservation efforts protecting and restoring crucial habitats along the African Eurasian flyway, funded by the Ecological Restoration Fund operated by BirdLife International and the RSPB.

This intercontinental scale of conservation planning, which includes actions to protect critical refuelling areas for migratory birds, is exactly the kind of effort that requires international cooperation and finance. It was thus welcome news over the weekend that the U.N. COP16 Global Biodiversity Conference in Rome made progress on a series of measures to support nature, including agreement on a road map for securing finances required for global conservation actions. This aims to provide finance for countries, especially those with key international biodiversity hotspots, to enable them to protect and restore vital ecosystems.

For us here, there are a number of ways we can participate in being part of the solution too. We can impart on decisionmakers here that we must do more to deliver on our commitments under Paris Agreement, which includes transformative policies required in energy, transport and agriculture.

Despite progress being made in the adoption of carbon budgets, Ireland has yet to bend our emissions curve in the right direction. Boosting climate finance for nations less able to afford mitigation action is also key. Current financial flows for climate change mitigation need to increase at least three times if we are to limit global warming to 2°C or below and achieve the Paris Agreement targets.

For those of us who have any say over how land is managed, even if its only the small patch around your home, much can be done to facilitate successful summers for breeding birds: 

• For the house martins, swallows and swifts, they need ample food and shelter to raise a brood successfully. Maximising the cover of native trees and shrubs, which support all the flying insects that these insectivorous birds rely on, is one thing to consider.
• Avoiding the use of pesticides, such as herbicides and ant spray, will also help maintain invertebrate life.
• Allowing access to long-held nesting sites in the barn or shed is important too.
• Similarly, you might consider putting up swift nest boxes to compensate for losses in nesting sites. Just the other day I was told about a Kildare farmer who has made an earthen sand bank and a large farm pond especially to cater for the nesting needs of migratory sand martins.

Countryside Bird Survey — volunteers wanted

For those with a particular passion for birding, participating in the Countryside Bird Survey makes a huge contribution to our understanding of the changing trends in bird life here. The data collected, by both professionals and volunteers, is how we track the changes in populations of our common and widespread birds over time. The Countryside Bird Survey is coordinated by BirdWatch Ireland and funded by the National Parks and Wildlife Service, and is now seeking suitably skilled volunteers to conduct surveys of a one km grid square twice during the breeding season.