Following a busy summer carrying out survey work on behalf of an environmental consultant I have a new found appreciation and respect, or lack of in some instances, for the management and treatment of freshwater courses in this country. Some of it boggles the mind and is incredibly worrying for those of us that take the time to delve a little deeper and take the time to appraise some of the ways that we, as a nation, regard and treat our national inland waterways. In some cases, the fact that fish, plants and insects still live in these watercourses is more an expression of the resilience of Nature rather than an endorsement of work that we as a nation have carried out and the attitudes towards the aquatic environment. But more on that at a later date; I have been fishing, catching and am generally in good spirits and would like to keep it that way. There are also some very encouraging positives that can be taken from Ireland and its freshwater fisheries in spite of our best efforts to eliminate them.
A few days on the water before getting back to college beckoned and the weather did not look good enough to risk a drive back to the east coast for tope so I took a couple of days on Galway Bay. Kayaks were launched and a couple of very good sessions were had. Plenty of pollock were caught with some of them just tiddlers ranging right up to some very nice individual fish indeed. Some of the other usual suspects appeared in the form of mackerel, scad and wrasse. Just fun fishing with lures and a great way to cap the ‘summer’ before we head back into a final year of college. The winds had slackened for the last couple of free days and it was wonderful to get afloat on flat water for a couple of sessions. I headed further west for one of the days on an unsuccessful ray hunt; better luck next time, I suppose.
With summer gone – I hear it will be on a Tuesday next year – the thoughts start to turn to the more realistic potential cold water captures and pike spring very much to the fore on that list. It would be fair to acknowledge that the poor pike has been very much on the receiving end of a raw deal in Ireland. Until recently they have been vilified in scientific reporting in Ireland in stark contrast to the reports compiled in more enlightened areas of the world. They have been persecuted with shooting, gill netting and illegal removals through poaching. Pike was a dirty word in this country for a long time. It still continues to be in certain areas despite recent studies showing that they are an indigenous fish and have been present in Irish waters for a lot longer than any of us have walked the face of the earth.
Times do change and we can only hope and pray that attitudes change with them, for to eliminate what could be a cash cow for Irish tourism seems reprehensible. To spend huge sums of money doing so is even worse. Whether to deliberately reduce their numbers through determined extermination programs or whether allowing their numbers to be reduced by allowing the wholesale removal of their numbers through illegal fish removal, we are letting a national resource and income generator to be plundered. We can only hope that somebody somewhere decides to take a look at some of the newer research papers available or to subscribe to some of the more modern ways of thinking when it comes to apex predators in their natural environment.
Explore the notion of trophic cascades; it was once thought that the amount of predators in an environment was directly dependant on the amount of prey items available. Trophic cascades occur when predators in a food web suppress the abundance or alter the behaviour of their prey, thereby releasing the next lower trophic level from predation (or herbivory if the intermediate trophic level is a herbivore). Essentially what this means is that an environment is enriched and enhanced by the presence of the apex predator. The apex predator keeps the numbers of prey below it in check; this allows species further down the chain to flourish and creates a far more diverse environment. Predators are also essential to keep genetic lines healthy by preying on the sick and weak. As I have mentioned before, apex predators are essential to their respective environments and their removal is folly and a gross misuse of hundreds of thousands of Euros. We spend money killing something that can make us money.
Excessive Plant Growth
I don’t believe that pike are the main danger to trout, I honestly do not. Pike and trout were able to thrive alongside each other for centuries before we took on the notion that we knew better than Nature. Other really worrying actions that happen ‘wholesale’ in Ireland is the spreading of phosphate fertilisers on our agricultural lands and forestry plantations. The spreading of these fertilisers usually sees at least some of it running off the land and into our rivers. According to studies done in Mayo, mass felling on forestry plantations has also been proven to cause huge spikes in phosphate levels running into our rivers. All these excess fertilisers still get to carry out their job but rather than fertilise the fields and crops they now fertilise in stream vegetation resulting in massive amounts of plants taking over the waterways. Excess plant growth may not seem like that big an issue but when submerged and emergent plant growth starts to choke up waters, we have a problem.
I have looked at quite a few rivers and streams that feed into some very well-known trout waters and there is no doubt that excess phosphates have created an explosion in plant growth within our waterways. An abundance of plant growth that takes over the feeder stream greatly reduces the ease with which fish can migrate upstream from the lakes to spawn. If they do manage to make the journey then the trout can find difficulty in locating a suitable spawning location; plants have to put down roots and these roots are usually binding suitable spawning substrates together making it very difficult for fish to cut redds for spawning. The problem is not exclusive to trout; any fish that migrates up rivers to spawn will encounter similar issues. In a bid to combat the streams becoming clogged up some try to remove the plants by dredging and digging out the water courses on their land. This act also goes a long way towards removing spawning habitat from our inland waterways which again is very damaging towards our aquatic environment.
Very Fast Growing Fish
So there you have it, a couple of paragraphs that may explain why trout/salmon numbers are dwindling in our lakes and rivers and it would appear that the problem, once again, is a totally man made one. And then we go and remove a large number of apex predators in the mistaken belief that our latest mistake may rectify the previous ones. As mentioned earlier, despite our bungling efforts Nature is resilient and an article that I saw in the Nenagh Guardian goes a long way to illustrating this point. The article opens with the regaling of the battle between Kevin Grimes and a fine pike that he had connected with while fishing on Lough Derg and weighing in at over 22lb she was a capture that most would be proud of. The size of the fish is not what was important about this capture though, more the speed that it attained that size.
As Kevin was landing the fish he noticed that there was a small tag attached to one of its fins. The tag stated that it was an Inland Fisheries Tag and Kevin recorded the number and then contacted his local IFI branch in Limerick to see if he could find out any other information regarding this fine pike. What he found out was a little surprising given that the tag had been placed on the fish just over six years ago. At the time of tagging the fish was recorded as weighing 3.5lbs which means that in just over six years the fish had gained 19lbs of weight. That is an incredibly fast growing fish and it has anglers speculating about what else may be in the lake and, if they were left alone, what truly staggering sizes could they attain? Derg is a rich lake with plenty of food for a pike to grow large in. Recent studies have shown Irish pike to be feeding preferentially on roach, followed by perch and then trout and the waters of Derg are able to provide for this diet. Derg is not the only water in Ireland that could be a truly outstanding mixed fishery capable of producing not only leviathan pike but huge salmonids and cyprinids too. Look at the examples of Chew and Llangorse in England and Wales. Both are perfect examples of how trout and pike anglers can effectively use the same sheet of water with great results.
With growth rates like that it can be very encouraging to envisage some species bouncing back even after the trouncing they have taken down through the years. The tagged pike reveals similarities in Irish growth rates that I read about many years ago in one of Dr. Ken Whelan’s angling book in Ireland. Unable to put my hands on a copy now I recall the writings that were penned in the seventies stating that a pike in Lake Windermere in the UK can take up to fifteen years to reach a weight of 15lb. The same species can attain that weight in Ireland in seven years. The earlier findings and the recent fish from Lough Derg gives an encouraging glimpse as to what could be. Can we get there?
It has been theorised that 80% of what we put onto the land ends up in the water. That really is food for thought but maybe if we left the pike alone and paid attention to what is happening on the land before it affects our inland waterways then we may take a huge step towards increasing salmonid numbers and creating a huge attraction for big pike hunters around the globe.