Celebrating World Wetlands Day: return of the cranes

Yesterday was World Wetlands Day. Held on 2 February every year since 1997, the Day aims to celebrate and raise global awareness about the vital role of wetlands for people and our planet. To the casual observer wetlands may not seem vital at all, but instead an inconvenient and undesirable quagmire of mud, mosquitoes and misery. The truth, however, is very different.

Wetlands take many forms, including rivers, lakes, ponds, marshes, fens, swamps, mangroves, estuaries, floodplains and lagoons. Why are they considered vital? To put it at its most basic, wetlands are all about water and so is life. The equation is very simple: no water equals no life. Whether we’re talking about drinking water, food production or storing carbon emissions, humankind needs healthy, thriving wetlands.

And so does the rest of life on Earth. Wetlands are vital for biodiversity: although freshwater wetlands cover less than 1% of the planet’s surface, 40% of all species rely on them.

But despite their importance, wetlands are in big trouble. The Wildfowl and Wetlands Trust (WWT) estimates that 87% of the world’s wetlands have been lost over the last 300 years, with vast swathes being drained for housing, industry and agriculture. Those wetlands that remain often suffer from serious pollution, and are also threatened by climate change.

Monty

The Ramsar Convention, which dates from 1971, seeks to secure international agreement and co-operation to protect wetlands. And yet, despite no fewer than 171 countries signing up to this intergovernmental treaty, the loss of – and damage to – wetlands across the globe continues unabated, with an impact on biodiversity that’s difficult to overstate. In this context, World Wetlands Day and similar initiatives – both large and small – are to be welcomed as a means of raising awareness of the continuing wetlands crisis.

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Mrs P and I are big fans of wetlands, which offer superb opportunities for birdwatching. We are lifetime members of the WWT, a UK-based conservation trust which seeks to “conserve, restore and create wetlands, and inspire everyone to value the amazing things healthy wetlands can do for us.”

Sadly we live around 90 miles (145km) from the nearest WWT reserve, so our visits aren’t as frequent as we’d wish. But every visit we’re able to manage is worth the effort, none more so than our 2014 trip to the Slimbridge reserve in Gloucestershire. Here we were able to witness first hand the positive impact of the Great Crane Project.

Eurasian cranes are unmistakeable birds, standing more than four feet (1.2m) high, with slate-grey plumage, a red crown and a bold white streak extending from the eye to the upper back. They were once common in British wetlands, and countless place names – like Cranford in West London, close to where I grew up – include the element ‘cran’ to signify a locality where these majestic birds were known to congregate.

But loss of habitat due to the drainage of wetlands led to a decline in numbers, and hunting made things even worse. For example, in 1251 King Henry III served 115 cranes at his Christmas dinner, while in 1465 a feast to celebrate the enthronement of George Neville as Archbishop of York involved the consumption of 204 cranes. I can only hope these medieval displays of unrestrained gluttony were followed by unrelieved bouts of chronic indigestion…serve the buggers right, I say!

Unsurprisingly, by around the year 1600 cranes had become extinct throughout Britain. They remained absent from the British landscape for nearly 400 years.

In 1979 a small number of cranes crossed the sea from continental Europe to settle in the Norfolk Broads. They began to breed three years later, but the location was kept secret to avoid the unwelcome attention of egg collectors. The population survives, and has crept into other parts of East Anglia and a few other isolated spots in eastern Britain. But cranes mature slowly and typically have poor breeding success, with the result that after around 40 years the descendants of the Norfolk population remain pitifully small in number.

Chris(tine)

With the prospect of cranes naturally recolonising other parts of their ancestral range being remote, conservationists needed an alternative strategy if the bird was to spread in reasonable numbers to wetlands in the west of Britain. And thus was born the Great Crane Project, with the aim of establishing a self-sustaining breeding population of 20 pairs on the Somerset Levels by 2025.

The project saw a coalition of conservation organisations (WWT, RSPB, the Pensthorpe Conservation Trust and Viridor Credits) join forces to work on this highly ambitious, ground-breaking project. Each year between 2010 and 2014, around 20 Eurasian crane eggs were taken under licence from Brandenburg in Germany to be hatched in the UK. In all, 93 chicks were carefully raised in captivity. Dedicated “human parents” hand-reared the youngsters, educating them in the ways of the world at “crane school” before releasing them into the wild on the RSPB reserve at West Sedgemoor on the Somerset Levels. Simultaneously, work was undertaken at some sites to restore and improve the habitat for cranes.

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When Mrs P and I visited Slimbridge WWT reserve in 2014, the prospect of seeing cranes never entered our heads. We’d previously enjoyed a couple of fleeting, distant views of cranes in East Anglia, but it seemed wildly improbable that any birds from the Great Crane Project would end up at Slimbridge, around 66 miles (106km) from where they were released.

And yet, amazingly, we were treated to fantastic views of a pair of cranes, strutting, preening and displaying just a few metres from where we were sitting. What a privilege, to spend an hour in such close proximity to majestic birds that once graced British wetlands in huge numbers, but which are now so scarce.

Monty

The coloured rings on the cranes’ legs make it possible to identify the individual birds we saw that day: the Great Crane Project website confirms them to be Monty and Chris(tine). Theirs was one of the first breeding attempts by any of the birds released as part of the Great Crane Project, but sadly they failed to raise any youngsters, either in 2014 or subsequent years.

The 2020 Annual Report, authored by Elizabeth Antliff-Clark and Damon Bridge from the RSPB, indicates that the cranes released between 2010 and 2014 have so far fledged 31 youngsters, of which 27 are still alive. Sadly 2020 was not a particularly good year for breeding success. The annual report tells us

“27 pairs of breeding age birds were observed in 2020 – two more than last year. Of these, all 27 pairs were thought to be holding territories. 15 pairs made confirmed or probable breeding attempts. Because monitoring activities were minimal on account of the Covid 19 restrictions, there were a higher proportion of pairs in the ‘possibly bred’ category than in previous years so it is likely that this confirmed/probable figure would have been higher in a ‘typical’ year. Nine of the 15 pairs successfully hatched chicks with four of these going on to fledge.

The 15 confirmed and probable nesting attempts this year were made on the Somerset Levels and Moors (7 prs); WWT Slimbridge Reserve Gloucestershire (5 prs); Oxfordshire (2 pr); Cambridgeshire (1 female).”


SOURCE: The Great Crane Project 2020 Report Public Version (section 4.1), published on Great Crane Project website, retrieved 28/01/21

The report goes on to suggest that the explanation for 2020’s poor success rate lies in the near-drought conditions experienced at the time, which led to the drying-out of nest-sites and an increase in predation. If this is correct then last year’s poor performance may be regarded as a blip, and improved breeding success can reasonably be anticipated in 2021.

Let’s hope so. Cranes are a welcome addition to the biodiversity of British wetlands. If the Great Crane Project succeeds in its ambitions the species will continue its slow recovery from nearly 400 years of local extinction, allowing many more birders – and ordinary members of the public – to marvel at the sight of these magnificent birds. Wouldn’t that be an achievement for wetlands conservation!

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STOP PRESS: Just as I was about schedule this post for publication I picked up a press release from the RSPB / Crane Working Group. It reports that “the latest common crane survey reveals a record-breaking 64 pairs of cranes in 2020, bringing the total population [across all of the UK] to over 200 birds.” This number includes the birds released as part of the Great Crane Project and their descendants, and the descendants of the birds that returned naturally to the Norfolk Broads in 1979. The 64 pairs produced a total of 23 chicks.

What brilliant, timely news! There are bound to be bumps along the road, such as the drought that coincided with the 2020 breeding season, but taken as a whole the prospects for cranes in the UK look better than at any time since the Middle Ages. Give Nature half a chance, and She WILL fight back.

World Curlew Day

Yesterday – 21 April – was World Curlew Day! It probably passed you by: let’s face it, the news media are concentrating pretty much all their attention on one topic right now, understandably focussing on Coronavirus rather than curlews. Environmental issues aren’t perceived as a priority today, but while we follow the life and death struggle of fellow citizens coping with the Covid-19 virus, this magnificent bird is engaged in a battle of its own. Curlews are in big trouble.

The curlew is the largest of all European waders, an unmistakable bird with a brown body, long legs and a diagnostic downward-curving bill. And then there’s its liquid, evocative and haunting call.

Curlews overwinter on tidal mudflats and saltmarshes, and this is where Mrs P and I mostly see them, during our winter birding breaks. They used to breed widely both in upland and lowland Britain, but changes in farming practices have massively reduced lowland breeding success.

There are reckoned to be around 65,000 breeding pairs of Eurasian Curlews in Britain. Sounds like a lot, doesn’t it, until you realise that this is a reduction of about 65% since 1970. And given that Britain accounts for around a quarter of the world breeding population of these birds, the decline here is bad news for the species as a whole.

In 2008, Eurasian Curlews were added to the IUCN’s (International Union for Conservation of Nature) Red List of birds deemed to be of global conservation concern, becoming officially classified as “Near Threatened.”

Ours is not the only species of curlew under threat. A century ago the world boasted eight species of these large, long-lived waders. Today there are only six, of which three are on the Red List. As a group, they are claimed to be among the most threatened migratory birds on Earth. In response to their plight the first World Curlew Day was announced in 2018.

World Curlew Day has been described as “a grassroots initiative supported by environmental organizations such as BirdLife International and Wetlands International. It is a one-day global event aiming to raise awareness about the plight of curlews and to encourage activities to help them.” This blog post is my own modest contribution to the World Curlew Day initiative.

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The RSPB (Royal Society for the Protection of Birds) website summarises what is believed to be behind the decline of the Eurasian Curlew, noting that “the evidence to date suggests declines are largely due to poor breeding success alongside the loss of breeding grounds.” It continues:

“Like many wading birds, curlews lay their eggs in a nest on the ground – known as a ‘scrape’. The parents incubate the eggs for about four weeks, before the young leave the nest and roam around with their parents for a further four weeks, until fledging

Studies from across Europe have found that in most cases breeding pairs are failing to raise enough young to maintain stable populations.
 
Egg predation by mammals and birds has emerged as a key factor behind poor breeding success. However, this abundance of predation is in itself associated with changes in land-use and management.
 
Farming is essential to maintain the mosaic of grassland and wetland habitats curlews need, but large-scale grassland improvement ultimately leads to the degradation and eventual loss of breeding habitat. Changes in grazing pressure can also have a more direct impact in the form of nest trampling by livestock.”

SOURCE: RSPB WEBSITE, retrieved 18 April 2020

Having identified the problem, the RSPB is now urgently seeking a solution. Its Curlew Recovery Programme is undertaking research to better understand the management practices required to reverse the decline in Eurasian Curlew numbers. At the heart of the programme is a Trial Management Project.

The Trial Management Project is carrying out work at sites across the four countries of the UK, looking at a range of possible interventions including habitat management and targeted predator control. Baseline monitoring at the six sites in Scotland, England, Wales and Northern Ireland was undertaken during the 2015 breeding season, and research to identify and develop appropriate “curlew-friendly” land management strategies is continuing.

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In a separate project, the WWT (Wildfowl and Wetland Trust) started work last year on a project to protect curlews in the Severn and Avon Vales.

“The plan is to throw everything we’ve got at the problem in the vale. Curlew protection will be driven by farmers, that’s the logical reality. If we can work with them to turn things around here, that’s a great start. But we also want the vale to be a test ground for ideas that could be rolled out elsewhere and, ultimately, incorporated into new government agri-environment policy, so that farmers can effectively be paid for curlew-friendly management.”

SOURCE: GEOFF HILTON, WWT’s Head of Conservation Evidence, quoted in Waterlife: The WWT Magazine, April/June 2020, page 36

When a curlew nest is located within the study area, the WWT researchers must weigh up carefully the risks and benefits of intervention. Approaching the nest may alert predators to its existence, or may disturb parent birds and cause them to abandon it. However if the risks of predation are high, the project team may decide that, on balance, the interest of the birds is best served by approaching to erect an electric fence around the nest in an effort to keep foxes and badgers at bay.

The scientists are also keen to collect data that will give them a better understanding of the challenges to be overcome in halting the decline in curlew numbers. To this end researchers may visit the nest briefly to weigh the eggs and deploy a temperature logging device; the data collected can provide valuable insights into laying and hatching dates, and incubation patterns. The nest may also be visited again, just before the chicks fledge, to ring and radio-tag the birds so that further information on their progress may be collected at a later date.

The WWT’s most drastic intervention of all is “headstarting,” where vulnerable eggs and chicks are removed from the wild to be raised in captivity, before being released in a more favourable location. The recent article in Waterlife magazine describes the removal of 50 curlew eggs from airfields in East Anglia, where they would have been destroyed to prevent airstrikes. After being hatched and raised by the WWT, the young birds were released in the safer surroundings of its Slimbridge Reserve. A good news story, if ever there was one!

In doing my research for this post I’ve been shocked at the plight of the curlew, which is worse than I’d realised. It’s a bird I love to watch, and the prospect of its becoming extinct is heart-breaking. However the levels of work currently underway to better understand the problems it faces, and to find appropriate solutions, give me cautious grounds for optimism. I wish the researchers every success in their endeavours.