British Waterways claims to have zander ‘under control’ on itsnetwork of midlands canals but after a decade of trying, officialsadmit they may never manage to eradicate the alien predatorcompletely.
Illegal introductions helped zander to spread into the riversSevern and Warwickshire Avon in the 1970s.
From there the fish found their way into the network of Midlandscanals, where they first came to the attention of BW fisheriesofficers a little over 10 years ago.
Since then the fish have been removed and destroyed using electrofishing tactics. While the technique is reckoned to allow a highpercentage of larger fish to be removed, fry and fingerlings have ahigh escape rate.
Despite this fisheries officials believe the tactic is finallystarting to pay off along affected stretches of the Grand Union,Coventry and Ashby canals.
“We haven’t removed anything like as many this time, we took about1500 which is substantially down on recent years,” said regionalfisheries manager Keith Fisher.
“The average was around a pound or so, the biggest four to fivepounds, so the days of eight pounders are also over.”
Many specialist anglers would rather see the zander left in peace.They point to Fenland’s network of man-made drains and waterways asproof the fish will find their own level and live in balance withnative species given time to settle.
But Mr Fisher said the canals were a different kettle of fishaltogether to waters like Norfolk’s Middle Level and ReliefChannel.
“The canals are shallow and turbid with lots of small fish,because the invertebrates are kept down by the boat traffic,” hesaid. “There are a lot of fish here and very few big ones.”
The 2oz roach and skimmers in the average cut were ideal fodderfor smaller “schoolie” zander.
Elsewhere, scientists have noted zander causing a shift in preypopulations, with prey fish which survive growing to larger sizes inwaters capable of supporting them.
Fisheries officials argue the problem with canals is that theylack the natural food to enable prey species to grow big enough toavoid the zander’s predations, leaving the breeding stock of silverfish vulnerable.
Whichever way you see things, there’s no denying there’s atremendous waste going on.
Zander are simply killed and removed – despite the fact they are aprized eating fish on the menu of several upmarket Londonrestaurants.
“We’ve tried getting people up from Billingsgate before but itcosts us more to market them and it’s not worth the hassle by thetime we’ve graded them and sorted them all out,” Mr Fisher said. “We’re not allowed to transfer them alive either.”
Mr Fisher said declining returns on recent culls showed zanderpopulations were being kept down.
“We used to catch thousands and be up to our knees in them,” headded.
