Underwater farms vs. climate change - Ayana Elizabeth Johnson and Megan Davis — Transcript

Full transcript

1. 0:06For 3 billion people around the world,
2. 0:08seafood provides a significant source of protein and nutrition.
3. 0:12But recent studies show that 33% of wild fisheries are overfished,
4. 0:16while another 60% are fished at their maximum capacity.
5. 0:20In fact, over half the seafood we eat–
6. 0:23from finfish and shellfish to seaweed and algae–
7. 0:26isn’t caught in the wild.
8. 0:27It’s grown through aquaculture, or aquatic farming.
9. 0:31Farmed seafood is one of the fastest-growing food industries,
10. 0:34expanding in volume by 5.8% each year.
11. 0:38But different methods of aquaculture come with different advantages and issues–
12. 0:42some of which echo the serious problems we’ve seen in industrial agriculture.
13. 0:46So how can we avoid repeating the mistakes we’ve made on land, at sea?
14. 0:51What aquaculture approaches are we currently using,
15. 0:53and what does a sustainable way to farm the ocean really look like?
16. 0:57One of the most common aquaculture methods involves large pens made of nets,
17. 1:02where fish are farmed offshore in floating cages roughly 1000 square meters in size.
18. 1:08Commonly employed off the coast of Chile and in the fjords of Norway,
19. 1:11these fish, like many industrially farmed animals,
20. 1:14occupy stressful, overcrowded pens.
21. 1:17They produce massive amounts of waste,
22. 1:19polluting the surrounding areas
23. 1:20and potentially spreading diseases to wild species.
24. 1:24Worse still, since the antibiotics employed to fight disease
25. 1:27aren’t fully absorbed by the fish,
26. 1:29they get excreted back into the environment.
27. 1:32Net pens are also susceptible to escapes,
28. 1:35unleashing huge numbers of fish which compete for resources
29. 1:39and weaken the local gene pool with genes adapted for captivity.
30. 1:43Escaped fish can even disrupt local ecosystems as invasive species.
31. 1:48Other techniques,
32. 1:49such as man-made coastal ponds commonly used for shrimp farming in Southeast Asia,
33. 1:54create additional environmental problems.
34. 1:56Just like net pens, these ponds are prone to spreading pollution and disease.
35. 2:01Their construction also frequently destroys important ecosystems
36. 2:04like mangroves and marshes,
37. 2:06which protect coastal areas from storms,
38. 2:08provide habitats, and absorb tons of greenhouse gases.
39. 2:13One way to solve these problems is to farm fish on land
40. 2:16in completely contained systems.
41. 2:18Tanks and raceways can recirculate and filter water to prevent pollution.
42. 2:23But even fully contained facilities still contend with another major hurdle:
43. 2:27fishmeal.
44. 2:29About 10% of the seafood caught globally is used to feed animals,
45. 2:32including carnivorous farmed fish.
46. 2:35Researchers are working on fish feed made of insects and plant-based proteins,
47. 2:40but for now many inland fish farms are connected to overfishing.
48. 2:44All these obstacles can make sustainable aquaculture feel a long way off,
49. 2:49but innovative farmers are finding new ways to responsibly farm the seas.
50. 2:54The most promising solution of all may be to look lower on the food chain.
51. 2:58Instead of cramming large, carnivorous fish into pens,
52. 3:01we can work with natural ocean systems
53. 3:04to produce huge amounts of shellfish and seaweeds.
54. 3:08These low-maintenance flora and fauna don’t need to be fed at all.
55. 3:12In fact, they naturally improve water quality,
56. 3:15filtering it as they feed off of sunlight and nutrients in the seawater.
57. 3:19By absorbing carbon through photosynthesis,
58. 3:22these farms help battle climate change,
59. 3:24and reduce local ocean acidification
60. 3:26while creating habitats for other species to thrive.
61. 3:30Shifting to restorative ocean farming
62. 3:32could provide good jobs for coastal communities,
63. 3:35and support healthy plant and shellfish-based diets
64. 3:38that have an incredibly low carbon footprint.
65. 3:41In just 5 months,
66. 3:424,000 square meters of ocean can produce 25 tons of seaweed
67. 3:47and 250,000 of shellfish.
68. 3:51With the right distribution network,
69. 3:52a series of small farms, collectively the size of Washington State
70. 3:56could feed the planet.
71. 3:58Farms like these are already popping up around the globe,
72. 4:01and a new generation of farmers is stepping up
73. 4:03to pursue a more sustainable future.
74. 4:06Done properly,
75. 4:07regenerative ocean farming could play a vital role in helping our oceans,
76. 4:11our climate, and ourselves.