Missing Migratory Fish

7 Dec

Looking at the October 2019 Environment Agency fish pass numbers. There is undeniably serious cause for concern with regard to the number of migratory fish entering northern rivers. This not only applies to all North East and Yorkshire rivers but many Scottish rivers. Only a small number of rivers in the very far north of Scotland appear to have had a reasonable 2019 season.

The River Wear in particular has had a poor season. Over the last 10 years the number of migratory fish travelling through the two counters at Framwellgate Dam has averaged approximately 18,000 fish per annum. However over the last 5 years this has dropped to 16,000pa.

In 2018 the number counted totalled 8669 and this year the figure is unlikely to exceed 6,500 which will be an all time record low.

So just taking the last two years into account, the River Wear has lost approximately 19,000 migratory fish. Of course, with the very wet 2019 autumn some fish will have avoided the counters altogether, however 2018 was particularly dry so it seems very unlikely that a substantial number of the missing fish avoided the count.

The River Tyne to a certain extent has managed to maintain equilibrium over the last 10 years, but this year figures seem to be as equally alarming as the River Wear with only 275 being counted through Riding Mill in October. Projecting forward from the end of October it looks as if this years count will be close to 20,000 which will be the lowest figure since 2002.

One bright spot seems to be the River Coquet where anglers report a better year than past but of course any improvement from a historical low base seems a reason for hope. Unfortunately due to counter problems and consequential data shortages there is little opportunity to measure the improvement.

The River Till has also fished better, particularly for Sea-trout so it could be that both the Till and Coquet have benefited from the shortened T&J Net season. However, since the ‘ T net ‘ trial appears to have been a relative success, in taking Sea-trout but releasing Salmon, there is the imminent danger that the EA will revert to the traditional Sea-trout netting season of May until the end of August, putting further pressure on declining Sea -trout stocks. In which case all game anglers need to be on their guard and be proactive if the EA try to re-establish this programme.

So what’s behind this decline.? Well obviously no one knows, but everyone’s guessing.

Is it agricultural pesticides, run-off from commercial forestry, poor water quality, fish farming, netting and avian and inshore seal predation or is it a cyclical phenomenon?

Hopefully the ‘Missing Salmon Project will quickly tell us and enable swift action to be taken to counter the decline.

One interesting observation from the article ‘Missing Salmon’ posted below on 22nd of November 2019 refers to the loss of some 65% of smolts in one trial ‘ in river ‘ which will come as no surprise to anglers who watch our avian friends in action. Still better not to jump to hasty conclusions.

Speedy Salmon?

6 Nov

Fish speeds and ability to leap.

Ever wondered why some fish seem to disappear so quickly when spooked, then here’s your answer. The following Environment Agency chart gives the swimming abilities of the species named.

Interestingly the world record swimming speed for a human was set in 1990 in Nashville Tennessee by Tom Jager of the USA who recorded a time of 2.29m/s (equivalent to 5mph) over 50 meters. So by direct comparison, humans in water can be quite quick, but a fish out of water – well they’ve got no chance!

Durham Hydro – Update.

20 Oct

During the current season (2019) the number of migratory fish trying to enter the Archimedes screw chamber seems to have declined. This is in no small part due to the operators Durham County Council, to there credit, turning the screw revolutions down during the period May till the end of October. This has reduced the white water at the base of the screw providing less of an attraction to migrating fish. Although during periods of high water fish have still been using the Larinier fish pass at the side of the screw.

There does not appear to have been any significant fish mortalities this season and it is believed that the operators have still been able to generate sufficient energy to meet their needs.

The protective flaps over the chamber also appear to have worked and it is anticipated that these will be lengthened in due course as a further preventative measure.

Along with these measures the Environment Agency have commissioned an independent report from a company specialising in the design of fish passes. The report highlights flaws in most of the existing Framwellgate fish passes with recommendations and costs on how to rectify matters.

With the EA still under austerity controls, only limited funding is available and the EA have decided to bid for 2020 funding to improve fish access to the lower weir near to the Archimedes screw, one of the reports principal recommendations. This will entail using stop logs to reduce the flow through the central notch and diverting water to the notch in the weir adjoining the screw which will also be reduced in depth and widened to create easier access. At the same time work will be undertaken to the base of the Larinier fish pass to create more white water in an attempt to draw fish away from entering the screw chamber.

Everything depends on funding of course so let’s hope it happens.

Tees Barrage!

12 Oct

In 1995 a barrage was installed on the River Tees to combat industrial pollution and to also control flooding. However, for all the good the Tees Barrage has done in helping clean the river up and reducing flooding. The barrage causes a significant barrier to Atlantic Salmon & Sea trout from reaching their spawning grounds. Due to the design of the barrage gates this also creates a catastrophic amount of predation below the barrage as the migratory fish do not have a free flowing passage through the barrage.

There is currently a fish pass installed at the barrage, but this was an after thought during the initial design as the designers were led to believe there were no migratory fish in the Tees due to the pollution having killed of the majority of aquatic life.

A petition has been set up to have a fully functioning fish pass installed on Gate 1 that is available for 24 hrs a day, everyday, to allow the free movement of fish both upstream and downstream. Currently fish can only pass at very specific tide times and if they miss this window of opportunity they are then at extreme risk of predation.

The Tees is categorised by the Environment Agency as “at risk” due to it’s low returns. If nothing is done and done soon, we could loose this iconic species from the Tees altogether.

Please support the campaign to get the Tees back to the once great salmon river it used to be.

The petition link is :- http://chng.it/ZcH9z9s9yN