So this paper estimates increases in metabolic activity of between 5 and 7 percent. I was curious about how big a deal this might be, and in the discussion they

So this paper estimates increases in metabolic activity of between 5 and 7 percent. I was curious about how big a deal this might be, and in the discussion they claim that southern otters are potentially energetically stressed, linking to a single 2016 paper which was based entirely on freshly washed up dead otters. There are a lot of studies involving marine associated organisms that rely on opportunistic carcasses, but I have a pretty consistent issue with all of them: you are selecting for the animals that died. The problems with this, especially when the topic is something like energetic stress, should be obvious. Southern seat otters are only present in a fraction of their historical range, and those places are among the most productive on the entire western coast. Food for otters is abundant, and studies have shown that otters eat a very wide range of foods (although individuals tend to specialize on only a subset). This is an interesting study, and I am even willing to believe them when they suggest that their estimates are likely to be lower bounds, but I'm not very convinced that the levels of disturbance are particularly ecologically relevant. When a population of apex predators is as dramatically reduced as otters are, in ways that affect the rest of the ecosystem to much lesser degrees, food and energy limitation are very rarely issues. I wouldn't go so far as to say that this is for sure not an issue, but I would want to see much stronger evidence than has been provided by the literature so far.