The Secret Angler

Like too many natural assets in this country, chalk stream fishing is heavily privatised, and owners of the best fishing rights can generate a substantial rentier income. Inevitably a class of middlemen have piggybacked this business, such as Simon Cooper and his company Fishing Breaks. Through his company you can buy yourself a day on rivers like the Test in return for a substantial sum (£400 plus in mayfly time). Given the investment, customers, the more mercantile ones anyway, expect to catch fish, preferably a lot of fish. So Cooper’s piece on catch and release in November’s Trout & Salmon magazine was not that surprising.

Under the magazine’s rather crass byline, dogma of do-gooders, he criticises the current preference for releasing trout instead of knocking them on the head. He rashly overstates his case by describing catch and release as an “Orwellian mantra” (perhaps he hasn’t read Orwell). His reasons have been put before and were never convincing then.  The first concerns the attitudes of hostile forces, the old argument that killing fish justifies the angling, whereas putting them back doesn’t. It’s a feeble point, if only because those who hate fishing don’t much care either way — it’s people fishing they can’t abide.

The second argument is commercial and therefore more understandable from his position. Fish caught and returned become more skilled at avoiding artificial flies, they become much harder to catch. This is certainly true, although I think fishing pressure has a similar effect, whether or not a fish is caught. Difficult fish make for unhappy clients, which is bad for business. Since the waters on Fishing Break’s inventory cannot be rested unless income is sacrificed, the implication is that Cooper would prefer to kill and restock. He extends the argument to wild trout fisheries by suggesting that taking 12-inch fish will not reduce the population because the trout won’t live much beyond that sort of age. This might be valid if the replacement rate were higher or at least equal to the harvest rate, but on the hammered waters that comprise his inventory this would be most unlikely.

Wild trout are under great pressure in the South through environmental damage as well as daily angling. At one time the welfare of trout populations was barely considered. Now at least we are aware of the value of the wild brown trout and we balk at killing them. Even if on certain blessed rivers this is not strictly necessary, it is better than the old philosophy of making a good basket. Commercial imperatives should have no bearing. Decades of stocking have completely changed the famous chalk rivers where the extant wild trout are swamped by the money-making interlopers. Wild fish need all the care we can give them.

Spend a little time out fishing, no matter where, lake or river, talking to other anglers, and soon enough the topic of cormorants will arise. Nearly always the view is the fishing was so much better a few years ago before the cormorants began eating all the fish. I’ve heard this said on numerous occasions, even on waters that have plenty of fish. Exaggeration is commonplace too. The claims of mighty catches a vague number of years ago is rarely plausible, especially when such boasts have been around well before cormorants were deemed to be a problem. The question also arises of whether fish declines, assuming they are occurring, are caused by cormorants or some of the many other factors we know affect the freshwater environment.

The cormorant that has appeared around many of UK waters over the last 30 years is the continental sinensis subspecies. This is not the same bird as that found around our coasts and the rise in its numbers has nothing to do with marine fish stocks. Cormorants in Europe were heavily persecuted up to the 1970s. Now they are protected the population has increased substantially and birds have migrated to the UK. Lobbying in Europe gained permission for selective control where it could be shown that fishery damage is occurring and where other control methods don’t work.

Now the Angling Trust has released a paper calling for cormorants to go on a general shooting licence, giving clubs and fishery owners the right to kill birds at will. The paper goes in for some hyperbole: ‘a massive and unsustainable increase in cormorant numbers…’, ‘decimated by cormorant predation’, etc. Perhaps unwisely it cites the Avon Roach Project, claiming an EA stock survey in 2005 showed roach stocks to be ‘perilously low’. In fact the EA data show nothing of the sort. Unless there is other data not included in this otherwise comprehensive set, the claim is exaggerated at best. Further, the person who started the ARP, refers to the cormorants as ‘not even British’. Not a good choice of words in today’s xenophobic climate.

The AT cites a number of academic research papers in support of its case. Notably very few concern research in this country. The majority are on work done in Denmark and other European countries, and one in Japan. Out of 26 references, only two are both in peer-reviewed journals and describe studies carried out in Britain. I wonder whether the authors of the AT paper have actually read these.

The Danish publications in particular do find that cormorants consume a significant quantity of fish. Others are ambivalent; some find that fish are not greatly impacted by cormorants, some find only certain species are affected. A general observation is that it depends on the kind of water and the local geography.

I’ve taken a look through the journal research papers published on the topic of fish predation and cormorants. Most are not available to the general public, unfortunately, although they are technical papers and not digestible reading. I found that surprisingly little research has been conducted on UK fisheries, and much of that is 20 years old or more. One useful review article by Catriona Harris et al in 2008 considers the impact of piscivorous birds in Scotland. The conclusion is important:

‘In summary, there have been few quantitative studies undertaken that have actually demonstrated reductions in [fish] population size or productivity as a result of cormorant predation in Scotland’

Stewart (2005), cited by Harris and also the AT, examined the effect of cormorants on Loch Leven. This amply demonstrates the difficulty with these studies. The area of water is so great that only rough estimates of fish population can be made, and these are very uncertain. Similarly the total number of fish taken by cormorants is also an estimate with large uncertainty. This leads to some perverse results in which upper estimates of predation exceed the fish population. It is still a viable fishery so we know not all the trout have gone. Quantifying impacts on fisheries is clearly extremely difficult.

Cormorant impact on natural waters is either uncertain or thought to be slight. But it may well be a different matter on waters which are created specifically for fisheries and are densely stocked. Ian Russell at Cefas in 2008 conducted an experimental study on fish refuges, comparing predation on two neighbouring experimental ponds, one with refuge cages. The control pond (without refuges) was heavily predated, removing the majority of stock, whereas the pond with refuges only lost around half. This shows, given the right conditions, cormorants will scoff with abandon. But one should take into account the artificiality of the arrangement, a control pond with no weed or debris, also clear and shallow — an ideal fish restaurant from the cormorants’ point of view. In an earlier paper, Kirby et al noted:

‘Indeed, the current diet of the cormorant appears to have been strongly influenced by man, who has altered the natural balance of fish stocks in many situations (e.g. trout stocking) and perceived problems are more frequent in such artificial situations.’

Overall there is little evidence to suggest cormorants are having an adverse impact on natural populations of fish, but some does point to problems with cormorants in artificial waters. The question is what to do in the latter cases. Anglers clamour to shoot them, but here the evidence for the effectiveness of culling is lacking. Rather than reducing bird populations, Chamberlain et al found that shooting caused them to grow. Cormorants killed are just replaced by others from the mobile population. They are opportunists and will fill any food-ready vacancy. The only way cormorant numbers could be reduced would be a return to persecution throughout the UK and Europe. And that isn’t going to happen.

So how will the AT’s representation and that of all other anglers to DEFRA be received? Given the lack of evidence of cormorant damage on the scale many anglers believe, and the evidence that shooting does nothing to reduce numbers, it is most unlikely that a general control licence will be granted. Cormorants, like otters, will have to be accommodated. That means adapting fisheries to minimise their impact. Wildlife experts say that cormorants, and all birds, need somewhere safe to rest between fishing dives. The further away from the water, the less likely the birds will choose that source of food. Dead trees are a cormorant favourite, as are islands or man-made objects in the water. Reducing these may reduce the cormorants. Natural weed growth, woody debris all help the fish avoid becoming a meal. And above all, lower fish densities make life harder for the birds.

The INTERCAFE project seeks to bring interested parties — anglers, fishery owners, scientists — together so that some resolution to the conflict between cormorants and fisheries might be found. This is probably the best way, perhaps the only way forward. We are going to have to live with cormorants.

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