Fish are a renewable resource as are fishermen but fishermen are not the only consumers of the renewable resource they exploit for sustenance. This creates an imbalance in the renewability of the renewable resource. Since there are more consumers than fishermen which creates more fishermen than fishable regions (assuming the relocation of fishermen to new regions to prevent over-fishing) there is an imbalance of renewbility. Factor in the reduction of spawning grounds for various species (some to environmental pollution of waterways, seas and oceans, some to overfishing of streams and ponds, some to taking catch that is too young, pregnant or the wrong gender, some to the reduction of long-term gestation mammal-aquatics lumped under fishing) and the result is a rapidly reducing renewable resource.
We talk a lot about the need to reduce consumption while we increase our population density and reduce the environment in direct ratio to human expansion; the need to shift to renewable resources while we cut the renewable possibility out from underneath the resource and simultanously increase the consumption requirements through need (population), economics (price-wage-employment option of fishermen and all related jobs between ocean and fork) and want (now that it is renewable everyone thinks it's okay to switch to resource reliance that the resource was already unable to sustain to start with). Renewable resource takes a lot of factors to renew itself and if we consider one resource renewable but then prevent the other factors fom both doing their jobs of renewing their related resource(s) and successfully renewing themselves because we only identify "popularly recognized" renewable resources instead of realizing that all resources fall under the heading renewable resource and that consumption cannot be reduced when the population in question (ours) continues to renew itself at rates not in keeping with either its environment or the availability of renewable resources we see that we are sliding quickly down a slippery slope.
This doesn't even take into consideration the existence of other fish-eating creatures like bears or other fish or a whole list of mammals nearly invisible to us in their obscurity. When we make resources renewable then overtax them while undercutting them thus reducing their viability for the animal world as well as the human world and call this resource management we really endanger ourselves as a species.
Sticky situation. Food prices worldwide have gone up 40% since 2006. Starving third world countries are absorbing the initial impact but worldwide, we are all starting to feel the pinch. But we still think shark fin soup is a great idea: an overpriced bowl of soup with a fin cut from a shark that is in all other ways inedible and therefore unusable and the delicacy of a nation steeped in a long history of resource management (Japan). Hopefully, our learning curve improves soon.
Fish is going to be a nice by-product of a creating a permaculture landscape. I plan on building some ponds the old method way, then will stock them with fish to supply myself another source of meat. But I'm working from the uplands and creating vernal ponds first and slowly moving down the valley.
I can't taste much difference between cat fish and tilapia. they both require seasoning. Tilapia is excellent on the grill with a little cajun seasoning. I have stopped eating so much tilapia since the news about the reversed omega ratios, although I'm betting that is a result of the way they are fed in the farms. just as feed lot beef has bad ratios and grass fed doesn't as well as the eggs and milk from factory farms vs. grass fed operations. I'm sure I could grow catfish and several of the places we have looked at have ponds that I'm sure I could pull a few out of today.