I agree entirely with your last point Paul. For all the talk of the impact of otter predation over the the course of the last 10-15 years, anglers still haven't put together any sort of a case that could be used to influence policy makers into implementing any sort of control measures (lethal or non-lethal) or mitigation strategies. Anecdotal evidence simply won't cut the mustard with policy-makers, only thoroughly researched, hard empirical data will.
Look what the shooters did in the 60's and 70's when grey partridge numbers were on the floor and the lengths they went to to understand the ecology of the species, the habitat requirements and the impact of predation. In the space of a little over 10 years, one University alone (Southampton) had produced over twenty PhD theses related to grey partridge conservation. Central to all this work was late great Dick Potts of the GWCT, who identified three main causes of the partridge decline: reduced chick survival reduction in chick-food invertebrates (due to herbicides), lack of suitable nesting habitat, and poor nesting success due to predation. He brought them together in a computer model to predict their relative importance and synergistic interaction, and developed a theory known as the “three-legged stool”, if one leg failed, the partridge “stool” would collapse. A theory which has stood the test of time and made a hugely important role in the conservation of the species, and other farmland birds.
And for those that genuinely believe that otters are the primary cause of barbel decline, then simply resigning to the view Joe Public that thinks otters are cute (do they?) and that nothing can ever be done is a bit of a cop-out isn't it? There are plenty of examples of predator control right across the conservation sector. But generally, with the exception of badgers, most of these interventions are backed by the science.
