July 26, 2010
By my estimation, seventy-five-year-old author Dr. Sylvia Earle has spent more than 1% of her life underwater. If her dives were connected in time, it would be as if she slipped into the ocean on New Year’s Day and did not re-emerge until some time after Labor Day.
Her book chronicles her experiences as a 1960s pioneer in underwater exploration, with stirring accounts of the inquisitive fish and mammals she met in the deep blue. Anthropomorphizing these animals would be an insult, given all the trouble humans have caused by overfishing, pollution, and acidification of the oceans. With these issues, she deftly takes an animal’s perspective in deconstructing our troubled oceans.
I once found an enterprising hermit crab with its vulnerable posterior neatly tucked into a discarded Bayer aspirin bottle, a modern, lightweight, durable substitute for a traditional snail shell. A decorator crab on a nearby reef had artfully placed a disposable fast-food ketchup envelope on its back along with bits of algae, hydroids and normal camouflaging elements. The ketchup container actually helped the crab blend in with other trash.
Over half of all humans live near the coast where impacts are felt from habitat destruction to overfishing. One report in the journal Nature found industrial fishing has removed 90% of all large fish from the ocean. As oceanic currents sweep away human litter, a convergence of garbage is amassing in the middle of the Pacific Ocean. To make a small dent in the trash issue, Earle tells of the Ocean Conservancy’s yearly coastal clean-up that in 2008 drew participants from 100 countries, collecting 6.8 million tons of trash with the top 10 offenders being: 1) cigarette butts; 2) plastic bags; 3) food containers; 4) caps and lids; 5) plastic bottles; 6) paper bags; 7) straws and stirrers; 8) cups, plates, eating utensils; 9) glass bottles; and 10) beverage cans. So many of these items are food related, which is a sign to me that our food system is in disrepair.
After seeing this list, I was imagining how short-circuiting the flow of trash into the oceans could have more than just environmental benefits. If we could phase out soda (and their bottles) from store shelves we would benefit the oceans and reduce obesity and type II diabetes rates associated with the consumption of sugar-sweetened beverages. Stop people from smoking cigarettes, the single largest cause of cancer mortality, and we would also remove the single largest type of trash polluting our coasts. This underscores the intricate linkages among our health, our food systems, and the health of the environment.
Earle jolts the senses with her outlook for the oceans and before the reader can get too depressed, she interjects just the right amount of wonder and amazement in the great opportunity to explore the oceans. We may know more about the moon than we do about deep-sea regions. For example, the Marianas Trench off the coast of Guam, the deepest known area of ocean, has been visited three times: 1960, 1995, and 2009. These areas are inhospitable to even the most intrepid explorers, and hold an amazing diversity of life.
After building a case for the oceans being in trouble, Earle provides solutions to save the oceans. She applauds “smart aquaculture” for providing sustainably farmed seafood products to meet human demands. She acknowledged both multi-trophic aquaculture, an integrated approach using fish at different levels of the food web in one system, and recirculating aquaculture, a closed system that reuses water and filters out waste, as ways forward.
Earle urges consumers to eat smaller fish and lower on the food chain. Eating large fish that are slow to mature, such as tuna, depletes the tuna population of its most fertile group—the only ones who have a chance to repopulate the ocean. Eating lower on the food chain means skipping over wild-caught carnivorous predators like swordfish, salmon, mahi-mahi, tuna and shark, and aquaculture-raised carnivores like Atlantic salmon. An analogy to land-based food webs would be eating herbivores instead of top-level carnivores like wolves, tigers, and grizzly bears.
The book concludes with recent advances in ocean conservation, noting that only 0.08% of all oceans were protected as of 2008, though her goal is to permanently protect 10-30% of the ocean from human exploitation. To help arouse public support for ocean conservation she worked with Google Earth director John Hanke to launch in early 2009 a global online map of the oceans. For her mapping and conservation efforts Earle received a 2009 TED prize, among a long list of accolades, for her continued work protecting the Blue world.