In a nutshell, the Unnatural History of the Sea is a great book, but pretty damn depressing.
Humankind has been fishing for centuries. Unfortunately, there aren’t many records of any sort from the early days of fishing, but there are a few journals. What Roberts has found boggles the mind – flora and fauna on an exponentially larger scale and abundance than that found today. He reports rivers that were more fish than water when it came time for fish to spawn, islands covered in sea turtles, and fish many times the size of those in existence today.
The history of the sea is a story of shifting baselines, the change in environmental norms as human generations pass. Those huge sea creatures in huge numbers declined as the populations were fished. See, fishing naturally selects the larger animals first – the bigger, fatter, and older the fish, the more valuable it is. As the larger fish are removed, people get used to seeing only smaller ones, and fewer of the fish in general. It becomes “normal” for only a few fish to be around when there used to be huge schools.
The advent of trawling is pointed to as a major event in the history of the sea. Trawling enables fishermen to pull the greatest number of fish from the ocean with the minimum effort (that is not to say that fishing is easy – everything I’ve seen indicates that it is brutally demanding work).
Naturally, removing the majority of fish from a population plays merry hell with the health of the population. As it turns out (this was news to me), the reproductive power of fish increases as they age. So the older, larger animals crank out more eggs/sperm than the smaller, younger animals. This means that the small fish that are able to escape the trawl’s netting aren’t as capable of restoring the population size as the larger fish. It’s a double-whammy for the population.
And that’s just regular trawling… bottom trawling is even more destructive to fish populations. The nets are weighted so they scrape along the bottom of the sea. Not only are animals removed from the environment, but the actual environment is torn to shreds in the process. Corals that take hundreds or thousands of years to grow are ripped up, as are the plants that fish and invertebrates depend on for food and shelter. Triple-whammy.
Most of the book can be summed up in the following statements – “Marine populations are in a nose-dive and many, if not most, might not be able to recover even if extreme measures are taken immediately. Human intervention in the ocean is the direct cause, particularly trawl-fishing.”
There is little hope in the book until the last few chapters. In those last few changes, Roberts has laid out what appears to be a very reasonable plan of action to save what we have left, help it recover, and still supply the world’s human population fish. The plan is multi-faceted, calling for changes in everything from the politics of fishing, to the act of fishing, to where fishermen are actually allowed to fish. The last bit is the most remarkable, and best explained.
Roberts calls for 20-40% of the ocean to be set aside as marine reserves. Marine research claims that these reserves will actually boost catches while protecting populations and keeping them healthy. There are a few marine reserves existing today, and apparently fishing near the reserve has rebounded to an astounding degree – in some cases, the population rebound happens in just a few short years, though the cases discussed in the book point out that the populations improve more as time goes on.
Naturally, a great deal of politics would be involved in getting his plan enacted, and a great deal of corruption would have to be wiped out. The political element makes me pretty skeptical that the needed changes will be made in time.
“Ghost fishing” is discussed (ghost fishing is the term for the death of animals caused by lost fishing gear), and the loss of marine life caused by litter (plastic in particular) are both discussed. I think most people are aware that a lot of plastic winds up in the ocean, where it poses a danger to sea turtles and adorable tap dancing penguins. What I was not aware of was the danger of tiny, microscopic bits of plastic – stuff that is put into facial scrubs or bits of plastic that have broken off larger bits. These bits enter the food web when they are consumed by plankton, which are in turn consumed by other animals, until the concentration can cause harm.
What isn’t discussed is chemical pollution. It’s just as well, I suppose. It was hard enough soak in the rest of the onslaught marine life is subjected to. I suppose it’s a testament to just how resilient life is… Still, I can’t help think that it’s probably time to quit pushing out luck and DO something about the oceans being emptied.
All in all, the Unnatural History of the Sea is a great read, especially when read in conjunction with The World Without Us. Still, have something light on hand. Something happy… ‘Cause this one is a downer.