Mey Akashah, "Sustainable Seas and Sustainable Seafood," Harvard School of Public Health, Harvard Medical School, and Harvard Extension School, May 1 2012.
Course: Human Health and Global Environmental Change
Scaling API-first – The story of a global engineering organization
Mey Akashah "Sustainable Seas and Seafood," Harvard
1. Sustainable Seas
&
Sustainable Seafood
Dr. Mey Akashah
Instructor, Harvard School of Public Health
Human Health and Global Environmental Change
May 1, 2012
Harvard School of Public Health (EH 278)
Harvard Medical School (HO703.0)
Harvard Extension School (ENVR E-165)
23. Overfishing
Overfishing refers to the removal of marine organisms from
the environment at a level that is not sustainable.
• Growth overfishing
– Biomass lost due to fishing greater than biomass gained due to
growth.
• Recruitment overfishing
– Spawning biomass of population reduced number of larvae
produced inadequate to replenish population.
• Ecosystem overfishing
– Rate of organism removal high enough to modify ecosystem
composition
• Often leads to system-wide detrimental effects.
• Economic overfishing
– Occurs when fishery resources are not being used in the most
efficient manner. Limit = cost of fishing > value of catch
26. Economic Impacts of
Overfishing
• 2006 study by Worm et al. examined the
sustainability of our current global fishing
industry
• Concluded that within 50 years, most of
the important fish species will be
economically extinct (Worm, 2006)
27. Magnuson-Stevens Fishery
Conservation and Management Act
• Primary law governing US marine fisheries
– Originated 1976; many amendments since
• Main purpose: promote optimal yield
• Mandates the use of annual catch limits
• Accountability measures to deter overfishing
• Calls for increased international cooperation.
• Criticisms – failure to stop overfishing,
minimize bycatch, promote accountability
28. Bycatch
• When fishermen are attempting to catch
target fish, many other marine animals are
inadvertently captured, such as:
– Sea Birds (albatross & petrels)
– Marine Mammals (dolphins, porpoises, &
whales)
– Sea Turtles (Kemps Ridley, leatherbacks, &
hawksbill)
– Non-Target Fish (undesirable species,
immature fish, females)
29. A ratio of 0 would reflect catching target species and nothing else (Harrington, 2005)
30.
31. Streamers tied to the long line floats which to serve to scare the birds away), they
require an investment of time and labor that fishers are not always willing to pay.
45. Good Vs. Bad: Seafood Choices
Check out:
• Oceans Alive
• Monterey Bay Aquarium
46. For information on marine
mammal/shark-friendly catch methods
and sustainable fish farming, go to:
http://www.montereybayaquarium.org/cr/
cr_seafoodwatch/sfw_gear.aspx#pole
70% from or modeled from natural sources30% from synthetics and vaccinesSlide care of Dr. Aaron Bernstein
Slide care of Dr. Aaron Bernstein
Refractory pain – resistant to treatment (often opiates) a non-addictive pain reliever 1000 times as powerful as morphinePreclinical trialsAlzheimer's diseaseParkinson's diseaseEpilepsySlide care of Dr. Aaron Bernstein
Extract of the horseshoe crab's blood is used by the medical industry to ensure that their products are free of bacterial contaminationIntravenous drugs, vaccines, and medical devicesTypical near-shore areas form the prime habitatseawater is a virtual "bacterial soup”can easily contain over one billion Gram-negative bacteria per milliliter of seawaterThus, the horseshoe crab is constantly threatened with infection.Unlike mammals,horseshoe crab lacks an immune systemit cannot develop antibodies to fight infectionHowever, does contain a number of compounds that will bind to and inactivate bacteria, fungi, and viruses.Slide care of Dr. Aaron Bernstein
Slide care of Dr. Aaron Bernstein
a neotenic salamanderclosely related to Tiger SalamanderNeoteny -juvenilization or pedomorphismthe retention, by adults in a species, of traits previously seen only in juvenilesLarvae fail to undergo metamorphosisadults remain aquatic and gilled. originates from numerous lakes, such as Lake Xochimilco underlying Mexico CityUsed in scientific research due to their ability to regenerate limbsSlide care of Dr. Aaron Bernstein
CLICK-THROUGH ANIMATION
Couldn’t go into discussion of fishing before talking about development Barrier Islands, like the key I grew up on, Manasota Key (add pic)Dynamic systems, act as a buffer to the mainland Migrating under the influence of changing sea levels, storms, waves, tides, and long-shore currents.
1ST IMAGECleary sea how it’s a barrier islandSea inlet on bottom rightBay and mainland to left2ND IMAGEAgain, you see the beaches on the right (the key is only wide enough for a sing road)On left, you see the bay and someone speed boating in it (this is where we have a lot of manatees, btw)Can see from at least the LEFT PIC, the transitory nature of these islands
Old Manasota Keywhere I grew upLittle developmentPlumbing, but no cable, things like thatWhat do you suppose development does to these areas?
Loss of sediment protection, loss of nursery and spawning habitat
NatGeoHow did you do on the fish quiz? What surprised you? (i.e, that China had greatest fisheries impact, that half of fish consumed is produced on fish farms, etc.) IF STUDENTS HAVN”T DONE IT, IT IS A QUICK AND INTERESTING GO THROUGH
Aerial hunting of tuna
Evidence that in some species, larger females can produce exponentially greater quantities of eggsThe BOFFF hypothesis, or Big Old Fat Fecund Female hypothesis, refers to this phenomenon.
Case Study:Collapse of Canadian Cod FisheriesOnce the largest cod fishery in the world, the northern cod industry off the eastern coast of Canada experienced a sudden collapse in population numbers in 1993. The specific cause was likely related to the local fishery scientists overestimating the numbers of new fish being hatched and entering the population (Myers, 1997).This failure of fishery managers and scientists to accurately estimate population sizes resulted in wide-spread social and economic disasters, ultimately costing the public billions of dollars in lost wages and social aid programs (Walters, 2004). The fishery has yet to reopen.
Similar to sea birds, endangered sea turtles can easily find themselves at the end of a hook after eating a scavenged fish. Once caught, the fishing gear holds the turtle under water until it drowns. Specifically, long-liners have been cited as taking as many as 200,000 loggerhead turtles and 50,000 leatherback turtles in the year 2000 (Lewison, 2004).
Bottom Trawlingfishing technique widely employed due to its high yield (despite its low efficiency), indiscriminately scrapes along the seafloor,effectively harvesting anything in its path (Kumar, 2006). The technique has been likened to the terrestrial process of clear-cutting forestry, and has similar impacts in that it has a tendency to leave the affected paths nearly devoid of life (Watling, 1998).
Small invertebrates living in the sediment, bottom dwelling fish, and other fauna in the benthic environment are uprooted, relocated, and often killed in the process.Sensitive corals that single-handedly create the foundation for entire ecosystems can be dredged up and killed much faster than they can replace themselves. This results in far-reaching impacts on organisms beyond the coral itself that makes its home in this habitat (Morgan, 2005).Finally, the delicate geochemical balance of the water can be disturbed due to re-suspension of minerals, chemicals, and organics stirred up during bottom trawling (Kumar, 2006).
If the turtle becomes entrapped in the net, it will drown if not promptly rescued.. In the 1980's, a device called a "turtle excluder device" became mandatory on shrimp fishing nets.The result was a nearly ten-fold increase in egg laying females in about ten years (NGS, 2003).However, as with any safety measure, it will only continue to be effective if use and enforcement continue.
One study, focused on trawl fishing off the western coast of Europe, found a high rate of marine mammal bycatch. In fact, the study found that the combined efforts of major fisheries in that area killed between 0.4 and 1.6 dolphins for every 100 hours of trawling. While the authors of the study did not cite how many hours of trawling typically occurred in this area per year, it was their assessment that this level of bycatch is biologically significant (Morizur, 1999). Many people will remember the large impacts that the tuna fishing industry had on dolphins in the late 1960's. Through customer focused campaigns, the fishery changed their techniques resulting in a large drop in dolphin deaths. More recent advances have focused on utilizing acoustics to ward off any dolphins that might become entangled in the net. (NGS, 2003)It is also interesting to note that there is some research demonstrating that dolphins intentionally come in close contact with nets. Extremely intelligent, they have been observed herding fish into pound nets in the western Atlantic, thereby making the fish easier to catch. Unfortunately, a small miscalculation or errant current can send the dolphin into the net entangling and drowning it.
The SLED (Sea Lion Exclusion Device) is designed to reduce the number of marine mammals such as seals and sea lions that are trapped in the trawl nets of squid-fishing boats.The device allows sea lions to escape through the top hatch, while squid pass through a metal grid and get caught at the end of the net.
North Pacific Trash Gyre (bottom-right)
Q: What’s this?A: A dead pelican with a stomach FULL of lighters, etc.