Sustaining Aquatic Biodiversity

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Transcript Sustaining Aquatic Biodiversity

Sustaining Aquatic
Questions for Today
 What are the major threats to aquatic
biodiversity (HIPPCO)?
 How can we protect and sustain marine
 How should we manage and sustain marine
 How can we protect and sustain wetlands?
 How can we protect and sustain freshwater
lakes, rivers, and fisheries?
 The greatest biodiversity occurs in coral
reefs, estuaries, and deep ocean floor.
 Biodiversity is higher near coasts because
of the greater variety of producers and
habitats in coastal areas.
 Biodiversity is greater in the bottom region
of the ocean because of habitats and food
HIPPCO – Acronym to Remember
Greatest Threats to Biodiversity
 H stands for Habitat Loss and
– 90% of fish living in the ocean spawn
in coral reefs, mangrove forests,
coastal wetlands, sea-grass beds, or
Restoring sea-grass beds in Galveston, tX
 The above areas are under intense
pressure from human activities.
(dredging, trawling, dams,
excessive water withdrawal)
 I stands for Invasive Species
 These bioinvaders can displace or cause
extinction of native species and disrupt
ecosystem services and human economies.
 USFW states that bioinvaders are blamed for
about 2/3 of fish extinctions in the US since
 84% of world’s coastal waters are being
colonized by invaders! (Water hyacinth, Asian
swamp eel, zebra mussel, Nile perch, are
some examples…p. 252 for details)
How do aquatic invaders spread?
 Many aquatic invaders are introduced
through ballast water that is stored in tanks
in large cargo ships to keep them stable and
then dumped into another bay.
 Example:
– The brown seaweed Unidaria or wakame that
was introduced along the California coast
– Chokes out native kelp forests that are habitat
for sea otters, fish, and others
Water Hyacinths
Zebra Mussels in the Great Lakes
Lionfish in Florida
 Lionfish were introduced to the Atlantic
through human actions, though the exact
mechanism is still being debated.
 Some believe they were dumped from
 Compete with native fishes such as grouper
and snapper for food
Common Carp
 The first P in HIPPCO is coastal Population
 More people moving to coastal areas
destroy habitat and increases pollution.
 U.N. Environment Programme (UNEP) in
2010 reported that about 80% of the world’s
people were living along or near the coasts
For more information visit:
 The second P is Pollution
– 2004, UNEP estimated that 80% of all pollution
comes from land-based activities.
 Humans have doubled the flow of nitrogen,
mostly from nitrate fertilizers since 1860. Similar
inputs of phosphorous have occurred. (They
cause eutrophication, which can lead to algal
blooms, fish die-offs, and degradation of
Pollution Continued
 Toxic pollutants from industrial and urban
areas can kill some forms of aquatic life by
poisoning them (i.e. Irrawaddy dolphins in
Mekong River at risk of extinction from DDT,
PCB’s, and mercury)
 Massive inputs of sediment and wastes
(plastics, sewage, etc) from land due to
construction of homes and recreation areas.
 The C in HIPPCO is for projected climate
 Sea levels rise
– Destroys coral reefs, swamp low-lying islands,
drown highly productive coastal wetlands, and
put many coastal cities such as New Orleans
under water.
 Mangrove forests that protect islands will be
destroyed or damaged.
 Industrialized fishing has depleted marine life at an
alarming rate.
 The “fishprint” is defined as the area of ocean
needed to sustain the consumption of an average
person, a nation, or the world.
– All the world’s nations together are overfishing the
global oceans by an unsustainable 157%!!!! 
 In most cases, this leads to commercial extinction.
 Fish species are also threatened with
biological extinction, mostly from
overfishing, water pollution, wetlands
destruction, and excessive removal of water
from rivers and lakes.
 Marine and freshwater species are
threatened with extinction by anthropogenic
activities more than any other group of
species!!! (OUR fault!)
Industrial Fish Harvesting Methods
 Trawlers (fishes and shellfish – shrimp,
flounder, scallops)
 Purse-seine (schooling fish - tuna, mackerel,
 Longlining (open-ocean fish – tuna, swordfish,
sharks, cod)
 Drift nets (leads to excess bycatch of
unwanted species such as turtles and seabirds)
– Bans on the length of driftnets have reduced use of
 Sonar and Spotter airplanes
Fish farming
in cage
Spotter airplane
Drift-net fishing
Long line
Float Buoy
lines with
Deep sea
aquaculture cage
Fish caught
by gills
Fig. 11-7, p. 256
Trawling Before and After
What can the government do?
There are different ways the government can
help the environment:
1. Pass Laws
1. Regulate people and fine those that break the law
2. Levy Taxes or subsidize for positive responses.
3. Educate the people
1. Community Outreach Organizations
2. Public Service Announcements
4. Create Reserves and Mitigate new land.
How Can We Protect and Sustain
Marine Biodiversity??
 CITES: 1975 Convention on International
Trade in Endangered Species
 The U.S. Marine Mammal Protection Act of
 The U.S. Endangered Species Act of 1973
 U.S. Whale Conservation and Protection Act
of 1976
 1995 International Convention on Biological
Wetlands are cool, K?
Wetlands are important because:
* they are natural filters
* they are breeding grounds for coastal wildlife
* they are very biologically diverse
How Should We Protect and Sustain
 Wetlands have been drained, filled in, or
covered over to create rice fields, crop land,
cities, and roads.
 Wetlands have been destroyed by
processes of extracting minerals and oil.
 AND to reduce breeding grounds of disease
causing insects.
 How to Preserve and Restore Wetlands??
– Mitigation banking: allows destruction as long
as an equal area is created or restored.
 Not the best idea though!
– Buy wetlands and restore them with help of
EPA or US Corps of Engineers
 Aside from HIPPCO, one way that humans
have destroyed freshwater ecosystems are
through the creation of Dams.
– Dams create different economic and
environmental benefits and problems.
– We will further discuss dams during our
renewable energy unit.