August 28, 2019 at 11:01 am #195525Ron SheldonGuest
My assessment of global fish stocks on a scale of 1 healthy and 10 being in peril would be a 5. I arived at this number considering both abundance available for harvest and their role in the ecosystem following the perameters of the discussion assignment. I chose 5 because it is just on the upper end of the median of the scale. My reasoning is that I don’t believe there are any fish stocks that are both abundant for harvest and balanced in their role in the ecosystem. How do I know? Simply put I don’t, but I will try and explain how I came to this number.
Let’s start with abundance for harvest. There is a term used by ADF&G called “locally abundant”. Typically it is applied to wildlife and it means simply that there is alot of a rescourse in small pockets of prime habitat. The same applies to our fish rescources. There are healthy populations spread out along a vast landscape. In between, there are probably vast areas that have none and other areas that have populations that are in peril. The problem is we don’t harvest where there are none and we don’t have consistent global measurement systems to really know if the population we are targeting is healthy or not. For these reasons I have to rely on the good faith of the fishing community and scientists that they are getting it right at least 50% of the time.
Health measured by the balanced role in the ecosystem is slightly more problematic. Let’s agree for argument sake that everything eats salmon. Well, how many can we eat without hurting another stock. As seen through the colapse of herring fisheries and the decline of pacific salmon there are numerous species of fish and marine mamals that are in jepordy. But yet, we still have a “healthy” salmon fishery with a bumper year of Sockeye returns in central Alaska.August 28, 2019 at 8:31 pm #195584smoswald2Participant
You bring up the important point of fish being more abundant in certain places. It’s easy to fall into the trap of believing that stocks are healthy based on data from one area, where in reality that may not be the case as that place may just be an anomaly. Therefore, it is important to consider data from a range of places, but this gives way to further complications such as a massive amount of data needing to be processed. It’s very complicated.
- You must be logged in to reply to this topic.