Not only is climate change having an impact on humans and how we live our lives, but wildlife too. Adam Rowlands, RSPB Suffolk Area Manager, explains the impact climate change is having on birds in the area.
The impacts of climate change are having mixed fortunes on birds, particularly in Suffolk. Erosion has brought change to brackish and freshwater habitats along the coast, and more can be expected with anticipated further rises in sea level and storminess. New freshwater wetlands have been created to replace those expected to be lost to the sea, providing refuges for rare breeding birds such as bittern and marsh harrier.
Modifying the sea defences at RSPB Havergate Island to allow surge tides to spill over the walls has created more dynamic brackish lagoons which have attracted spoonbills to breed successfully for the first time in 300 years. The breaches at the Suffolk Wildlife Trust’s Hazlewood Marshes have created intertidal mudflats providing great feeding for the spoonbills and many other waders and wildfowl, whilst the provision of islands has provided nesting sites for avocet and redshank.
The redshank has all but abandoned breeding on the saltmarshes on the estuaries over the last forty years, as saltmarshes have been lost to erosion and increasing water levels have resulted in more frequent flooding of nesting attempts.
However, healthy breeding populations of redshank and avocet have been established on nature reserves and wetlands throughout the coast, managed by a range of organisations working together to achieve the Suffolk Wader Strategy. You can read more at www.suffolkwaders.org.
This landscape scale approach delivers multiple benefits and will be essential in coordinating our approach to water level management, particularly with the threats of increased summer droughts combined with episodes of heavy rainfall that climate change is expected to produce.
Land managers will need to work together to find innovative ways to manage water more effectively to ensure our wetlands continue to thrive, and by providing wetlands at landscape scale, we may see other exotic colonists joining the spoonbills.
Little egrets have gone from being a national rarity to a frequent sight, now breeding in heronries on the Suffolk Coast and sightings of great white egret, glossy ibis and cattle egret are all increasing with the hope they may soon be attracted to nest.
The large flocks of avocet that grace our estuaries outside the breeding season are also a relatively recent phenomenon. Historically, the birds moved to the south-west of England to winter, where the climate was milder, but as the winter temperatures have got warmer, increasing numbers remain in Suffolk.
However, a similar scenario is unfolding on the European continent, where many of the birds that used to migrate to our shores for the winter are now stopping short and remaining in the Low Countries across the North Sea, leading to reduced numbers of wintering species such as wigeon and Bewick’s swan.
Climate change does present opportunities to improve and extend heathland and acid grassland habitats important for colonising and expanding species. Specialist species such as Dartford warbler which re-colonised the coast after a 60-year absence in the 1990s have benefitted from the restoration work that has taken place so far, with over 100 pairs now breeding.
The warblers, which are present all year round, have been able to thrive in Suffolk because of the milder winters. Woodlark, nightjar and stone-curlew all have a chance to increase and red-backed shrike, which last bred in Suffolk in the 1970s could return.
So, climate change presents threats and opportunities. Adaptive and innovative approaches will be required to increase the resilience of habitats to climate change. It will also be essential to limit non-climate related pressures, such as disturbance, to ensure that the birds have the greatest opportunities to breed successfully and survive the winter.You can read more about birds and climate change in the BTO’s Climate Change and the UK’s birds.