Climate-hit wetlands lay bare Britain's biodiversity struggle

• Wetlands threatened by climate change and human activity
• Fish kill in The Broads National Park has worried anglers
• Concerns rising over biodiversity, conservation efforts

THE BROADS NATIONAL PARK, England - As seagulls circled above and tourists watched in confusion, Duncan Holmes steered his boat through thousands of dead fish bobbing at the surface of the River Thurne in east England.

Holmes, 48, a retired engineer turned fishing instructor, was out one day in September to document the severity of a fish kill that has amplified concerns about declining biodiversity and fragmented conservation efforts in The Broads National Park.

A local fishing group estimated that hundreds of thousands of freshwater fish, mollusks and key insects died after successive high tides trapped inland by strong onshore winds - and exacerbated by a months-long drought - caused high levels of saltwater from the North Sea to surge upriver.

For Holmes - whose family has lived in the region for generations - there was "despair that you're seeing it again and again," he said, referring to the fish kill last year.

"I don't know how many times I've seen it in my lifetime," said Holmes, a member of The Broads Angling Services Group (BASG), a civic organisation for anglers in the area, which is Britain's largest protected wetland and a major inland waterway.

Fish kills occur periodically in The Broads, caused by abnormally strong saltwater tides or toxic algae blooms.

However, local anglers, conservationists and officials say the kills are getting worse each time - an illustration of intensifying threats to the ecosystem due to climate change impacts, including sea level rise, as well as human activity from farming to homebuilding.

Britain is a member of the newly-signed U.N. Global Biodiversity Framework - which has a goal to protect 30% of the world's land and seas by 2030, known as 30-by-30.

It also recently set its own new legally-binding environmental targets. Experts say what happens in The Broads may illustrate how effectively both of those goals will be met.

The national park, which spans Norfolk and Suffolk counties, is home to a quarter of Britain's rarest animals and plants.

Yet Holmes described the latest fish kill as emblematic of the area's disjointed and dysfunctional governance, which he and other local citizens said has hampered coordinated conservation efforts and risks thwarting long-term sustainability solutions.

The myriad government agencies that oversee The Broads — five separate entities deal just with different causes of floods, for example — have been hamstrung by budget cuts, slowing the collection and modelling of environmental data, according to conservationists.

In the case of the saltwater surge last September, Britain's Environment Agency (EA) responded by manually moving thousands of fish to freshwater.

Groups such as BASG have questioned how effective this was, given that 100,000 fish died in the River Thurne alone, it estimated, and at least three other rivers were affected.

A spokesperson for the EA did not respond to a question about whether fish kills have increased in recent years but said "severe saline incursions are likely to become more frequent and of greater magnitude due to the effects of climate change".

This is of growing concern to conservationists and officials working in The Broads, as each saltwater incursion affects entire food chains from larvae to aquatic animals and birds.

'Engineering, not nature'

About 2,000 years ago, the eastern part of The Broads was saltwater marsh - formed in a massive estuary - which acted as a buffer between the sea and the freshwater environment.

In recent centuries, however, people have dug thousands of kilometres of drainage ditches and installed pumps to dry the land for grazing and farming. That has led the land to sink, worsening already frequent floods and saline incursions.

Matthew Philpot, area manager for The Broads Internal Drainage Board (IDB) - the agency responsible for controlling water levels on the land via the ditches - said the region is "not a landscape of nature, it's a landscape of engineering."

"It's a landscape of convenience, within which nature has flourished," he said, acknowledging that drainage ditches have created key freshwater biodiversity habitats in their own right.

Holmes of BASG said he would like to see the channels and pumps removed to allow the area to "go back to a natural environment".

"Let nature do its thing to keep the salt where it should be and the freshwater where it should be," he added.

Some officials agree.

Rick Southwood at Natural England - the government's conservation advisory body - said that if residents in eastern parts of The Broads were willing, changing land use to allow a saltier downriver floodplain to redevelop would be beneficial for biodiversity and climate adaptation.

One obstacle, though, is that the drainage ditches are key themselves habitats, especially for invertebrates like the Norfolk hawker dragonfly, said Andrea Kelly, environment policy adviser at the Broads Authority (BA), which administers the national park.

The BA's latest assessment of species identified for priority conservation, from 2011, showed that 52%, or more than 1,500 species, were vulnerable to any water level rise, and 63% of all species "require fully freshwater conditions" to survive.

For rare ditch-dwelling insects such as the dragonfly and the swallowtail butterfly, an influx of salty water would be fatal - but it would also be "absolutely catastrophic" for those species if ditches dried out due to drought, Kelly said.

Either scenario could massively reverse biodiversity gains, said the ecologist, much of whose work centers on rewetting some sections of lowland peat in the park that were drained over the centuries, releasing millions of tons of carbon dioxide.

A recent study in the journal Nature estimated that Britain has lost more than 75% of its wetlands over the last 300 years.

Environmentalists are also concerned about climate change impacts on the ecosystem with projected sea level rise, harsher droughts and stronger storms set to affect species conservation.

Southwood - who has lived and worked in The Broads for 45 years - said he has witnessed declining biodiversity in the region and knows that the situation will worsen.

"We know the losses are going to take place, but it's incredibly difficult to predict over what sort of timescale," he said.

"It is going to be hard to achieve (30x30 targets) long term," he added, noting that addressing conservation targets is a sensitive topic for the public as the goals can be at odds with food production, jobs and housing development in the area.

Conservation, tourism and farming?

How the hundreds of thousands of people living in The Broads - about 6,000 of whom reside within the national park boundary - should handle the changing ecosystem has spurred fierce debate.

Efforts to advance ecological protection and climate change adaptation have to compete with tourism and farming, each of which contribute billions of pounds in revenue to the economy.

For example, if proposals to allow the eastern Broads to revert to floodplain were to take shape, conservationists said, scores of small-scale farmers would have to be willing to move or adopt wetland agriculture techniques for different crops.

Local authorities intend to build tens of thousands of new homes in The Broads in the coming years. Southwood, of Natural England, said land development in the region is the biggest factor in habitat and species loss he has seen in his career.

Officials like Southwood and Philpot said public complaints about patchy inter-agency coordination to tackle problems from flooding to land use conflicts were well-founded.

Still, there is progress, even though it is slow, they said.

A multi-agency coalition in The Broads was formed in 2015 to study and manage future flood risk. As part of it, the Environment Agency is working with authorities and civic organisations such as BASG.

And at a national level, the government has developed grants for farmers interested in transitioning to wetland farming and peatland restoration, which conservationists say would help meet biodiversity goals and have been trialled in The Broads by the BA.

Rob Wise, environment adviser for the area's National Farmers' Union chapter, said economics will ultimately drive any such transition, and government payments will have to be "long term" to encourage land use change.

But failing to take meaningful action to protect biodiversity would effectively mean the end of "our lives, our way of life, and livelihoods," said Paul Rice, chairman of The Broads Society, a local civic environmental organisation.

"(Our) main industries ... agriculture and tourism ... will massively suffer unless we can adapt to and work with nature."

(Reporting by Rachel Parsons, Editing by Kieran Guilbert and Laurie Goering)