Lough Neagh: Ulster Angling Federation warns that apparent disappearance of infamous Lough Neagh fly could cause 'complete ecosystem collapse' for birds and fish

Visitors to Lough Neagh's shores from Spring to Autumn could traditionally have been plagued by swarms of the infamous Lough Neagh fly or Chironomid.

While unpleasant to meet in a swarm, the flies are harmless, as having no mouth they are unable to bite.

But to many species of birds and fish on the Lough they are their key source of food.

Gary Houston, Chairman of the Ulster Angling Federation, told the News Letter: "We are concerned by the apparent collapse of the Lough Neagh Non-biting midge (Chironomids) populations on Lough Neagh."

Sources have advised him that the Agri-Food and Biosciences Institute (AFBI) at Hillsborough have not collected data on the fly populations since 1990.

"The NI Environment Agency (NIEA), Department of Agriculture, Environment and Rural Affairs (DAERA) and AFBI should all be concerned about the situation as the fly is a key part of the food web and ecosystem that is in a state of collapse," he said.

"Commercial fishermen and anglers would be concerned as there is no food for fish in the lough as fly populations decline, bird populations such as swifts and swallows and ducks would also be impacted. We are looking at a complete ecosystem collapse, meanwhile NIEA/ DAERA and AFBINI are asleep at the wheel."

Declan Coney is a former commercial eel fisherman on the Lough, who is originally from Ardboe, on its western shore."I'm hoping I'm wrong but I feel we could have lost the Lough Neagh fly," he told the News Letter. "The population has been in noticeable decline for 12 years."

In his view the main problem is the invasive Zebra mussels. He says the flies' eggs, which normally hatch on the Lough bed, are hindered from doing so by the sheer volume of Zebra mussels on top of them.

"The entire ecology of the Lough depends on the fly."

It is key to the diet of migrating birds such as swallows as well as the tree sparrow. The Lough may already have lost its population of Pollan fish, he adds and other fish that feed on the larvae may be at risk.

The Lough Neagh eel - a delicacy around Europe - is also dependent on the fly. In turn some 500 jobs are dependent on the eel industry.

He concludes: "Lough neagh Partnership, NI Water, DAERA, NIEA, The Lough Neagh Partnership and The Lough Neagh Fisherman's Co Op all need to sit down around the table and sort this. At the minute all we are getting is false promises."

The News Letter invited DAERA and AFBI to respond.

An NIEA spokesperson responded the fly was “previously commonplace” but offered no specific plan to investigate the issue.

"That ecosystem is complex and not all interactions are fully understood, but it is clear that introduced species such as zebra mussels and roach are contributing to ecosystem change in conjunction with pressures such as nutrient enrichment and climate change,” it said.

Lough Neagh flies "were previously commonplace and are not a protected feature for that reason" it said, though it acknowledged that they are a key food in the Lough Neagh ecosystem.

Counting the changing population is "only one of potentially hundreds of parameters which could be monitored".

Dr Neil Reid, a Reader in Conservation Biology at QUB, suggested that Zebra mussels creating a physical barrier to midge egg deposition seems "implausible".

However he added that the mussels "certainly" alter ecosystems because their dead shells can accumulate as deposits which might change the value of Lough Neagh's bed for fly larvae.

Chris McCarney, Biodiversity Education Officer with ABC Council, confirmed there is a very real problem with the flies.

"The Biodiversity Team have observed a decline in the numbers of Lough Neagh flies this year,” he said.

“A few years ago, the swarms completely covered the walls of Lough Neagh Discovery Centre and when in flight the flies looked like clouds of smoke above the trees. This year there have been Lough Neagh Flies about but nothing like the natural phenomena it used to be.”