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Issues This Week
The marine environment; fisheries, ocean pollution. Resource economics.
Open Access Resources and why they get over-exploited What are some open access resources?
Depletable and Non-depletable resources Your use does / does not diminish my use Examples?
Tragedy of the Commons
There will be terminology and math-like stuff, do not PANIC
Marine Environmental Issues
Oceanography:
physical structure; seawater composition; currents, oceanic topography Marine Ecosystems
Biodiversity and food webs
Examples: coral, kelp, intertidal zone, marshes, mangroves Human Impacts
Pollution
Emptying the Oceans Conserving Ocean Resources
Lecture material will focus HERE
Announcements
Problem with test question answer key…?
http://www.coml.org/medres/hmap7a.htm
www.shiftingbaselines. org
The decline of marine life
The Pew Oceans
Commission
Several recent bodies,
governmental and private, have
focused on how to become
better stewards of the resources
of the earth’s oceans.
The goal is to reach sustainable
harvest of resources, protect
oceanic food webs, protect
species diversity, and reduce
pollution.
June 4, 2003
3 year, nationwide study
Bur first
Good News
Bad News
Chemical Spills in the Ocean
- Better Navigation
- Double-hulled ships.
Lebanese oil clean-up; BBC, Oct. 26, 2006
Lots of different types of Harmful Algal Blooms (HAB)
On the issue of Ocean pollution
(dilution is NOT the solution).
- A large fraction of the surface zone and pycnocline are near shore.
- Pollutants released near shore, often _stay near shore.
- Near shore is where we gain the vast majority of resources we use._
The local perspective: S.F. Bay
we often hear of pollution and habitat loss…
Each year, 88 million pounds of pesticides and
toxic chemicals drain into the Bay
Adults are recommended to limit their
consumption of sport fish to 2 meals per month.
30% of Bay has been filled in, 92% of tidal
wetlands lost.
Less than 50% of original freshwater input now
runs through the Bay.
Some oceanographic issues to bear in mind for the present section, later in the quarter, and life in general.
- Ocean currents have a very large effect on climate. Factors that affect these ocean currents are poorly understood or modeled.
Some oceanographic issues to bear in mind for the present section, later in the quarter, and life in general.
- Coastal winds drive surface temperatures; which drives inland climate
El Nino events
Warm oceanic surface waters drove 2005 to be the largest hurricane year on record (21 named storms; 13 hurricanes)
An Ocean
Food Web
Topic Shift: From physical environment to biotic environment
Marine Biodiversity
Marine biodiversity is very high
Not at the species level, but at a deeper level of taxonomy
Of 33 known phyla (eg, chordata, mollusca, arthropoda), 32 are found in the ocean (18 on land) and 15 are exclusively marine
Some marine environments rival tropical forests in terms of diversity Coral reefs Mud bottom bay in Maine: > 1000 species of invertebrates
Globally, fisheries production and demand continues to increase. Humans consume a pretty diverse array of ocean resources.
High harvest has raised global concern of SUSTAINABILITY
Some have argued that global
fisheries are in a state of collapse
Worm, et al. 2006. Impacts of Biodiversity Loss on Ocean Ecosystem Services. Science 314:787.
Species richness scale
Fisheries are
historically
characterized
by a series of
catastrophic
collapses
Some
economic,
some
ecological
Whaling
Virtually all whaling is banned by International Whaling Commission (51 member nations).
IWC, formed in 1946, called for complete moratorium on whaling in 1985.
Why were so valued?
Whale Oil
Lighting. Whale-oil burned slowly, without an offensive odor. It was considered one of the finest oils for illumination used in an oil lamp.
For lubricating : Whale-oil was processed into fine lubricating oils for industries such as clock making.
Other uses : soaps, varnish, cosmetics, paint, …. Whale bone - Baleen
Buggy whips, Carriage springs, Corset stays, Fishing rods, Hoops for women's skirts, Umbrella ribs and many other applications where nowadays plastic or steel would be used. Meat
Data indicate that we are saturating (or over-saturating) capacity.
Example #1. Caribbean Coral Reef:
a cascade of human exploitation
Top Predator: Monk seal (extinct)
Large herbivores:
Sea turtles: hawksbill, green, manatee
All nearly extinct
Sharks and large fish--declining
Small fish – now being exploited
From J.B.C. Jackson. 1997. Reefs since Columbus. Coral Reefs 16(s) 23-
Exploitation down the food chain
On the
abundance
of sea turtles
“….but in those twenty leagues, they saw very many more, for the sea was thick with them, and they were of the very largest, so numerous that it seemed that the ships would run aground on them….” > Bernaldez on Columbus’ 2 nd^ voyage in 1494
Jackson asserts that the biomass of turtles (~660 million) was likely as large as the biomass of ungulates on the Serengeti and kept the sea grass beds trimmed like a lawn
Georges
Bank
Cold storage long-range fleets
Northwest Atlantic Ocean Fisheries
FAO 1997
New England, Canadian Maritime Provinces
Northwest Atlantic
Ocean Fisheries
FAO 1997
This has been managed for sustainability since the 1950s
Economic Collapse
FOR SALE
The Newfoundland Cod
Collapse
“In 1992, the devastating collapse of the cod stocks off the east coast of Newfoundland forced the Canadian government to take drastic measures and close the fishery. Over 40, people lost their jobs. The communities are still struggling to recover. The marine ecosystem is still in a state of collapse.” Greenpeace statement
Northwest Atlantic Ocean Fisheries
FAO 1997
This has been managed for sustainability since the 1950s
Resource switching
Northeastern Atlantic Fisheries
FAO, 1997
Franz Fischler, EU, closes Baltic fishery on April 15, 2003
Eastern Indian Ocean
Mediterranean and Black Sea
Western Pacific (China)
Southwestern Pacific (Australia)
These numbers are suspect
