Transcript Chapter 11
Chapter 12 & 13
Sustaining
Biodiversity:
Terrestrial and Aquatic
Species
Core Case Study:
The Passenger Pigeon - Gone
Forever
Once
the most
numerous bird on earth.
In 1858, Passenger
Pigeon hunting became
a big business.
By 1900 they became
extinct from overharvest and habitat
loss.
Figure 12-1
SPECIES EXTINCTION
Species
OBJ 12.1
can become extinct:
Locally: A species is no longer found in an area
it once inhabited but is still found elsewhere in
the world.
Ecologically: Occurs when so few members of a
species are left they no longer play its ecological
role.
Globally (biologically): Species is no longer
found on the earth.
Global Extinction
Some
animals have become prematurely
extinct because of human activities.
Figure 12-2
OBJ 12.2
Endangered and Threatened
Species: Ecological Smoke Alarms
Endangered
species: so few individual
survivors that it could soon become extinct.
Threatened species: still abundant in its
natural range but is likely to become
endangered in the near future.
Figure 12-3
OBJ 12.3
SPECIES
EXTINCTION
Some
species
have
characteristics
that make them
vulnerable to
ecological and
biological
extinction.
Figure 12-4
SPECIES EXTINCTION
The International Union for the Conservation of
Nature and Natural Resources (IUCN) publishes
an annual Red List, listing the world’s threatened
species.
The 2010 Red List contains 18,351 species at
risk for extinction.
US – listed by the Fish and Wildlife Service
• www.fws.gov
Figure 11-5
SPECIES EXTINCTION
Percentage
of various species types
threatened with premature extinction from
human activities.
Figure 12-5
Overview of Aquatic Biodiversity
Little is actually know about biodiversity
of marine and freshwater systems; only
explored about 5% of global oceans
Most Aquatic Biodiversity: Found near
shorelines and deep parts of ocean
Coral reefs, wetlands, estuaries, coastal
areas and deep ocean floor
IMPORTANCE OF WILD SPECIES
We
should not cause the premature
extinction of species because of the
economic and ecological services they
provide.
Some
believe that each wild species has an
inherent right to exist. (intrinsic value)
Aquatic Ecological and
Economic Services
Globally,
6% of total protein for food
consumption comes from marine fish and
shellfish
Seaweed and other organisms provide
pharmaceuticals, cosmetics, food stabilizers
and preservatives (ie. carrageen in yogurts
and ice cream)
OBJ 12.5
WHY???
Conservation
biologists summarize the most
important causes of premature extinction as
“HIPPO”:
Habitat destruction, degradation, and
fragmentation
Invasive species
Population growth
Pollution
Overharvest
Human Impacts on Aquatic Biodiversity
Greatest threat is habitat
loss- destruction and
development of coastal
wetlands, coral reefs
(tourism), mangroves
(coastal development &
shrimp aquaculture) and
the ocean floor
(trawling/dredging)
Trawling
HABITAT LOSS, DEGRADATION,
AND FRAGMENTATION
Reduction
in
ranges of four
wildlife species,
mostly due to
habitat loss
and
overharvest.
Figure 12-7
Case Study:
A Disturbing Message from the Birds
Human
activities are causing serious declines
in the populations of many bird species.
Figure 12-8
Case Study:
A Disturbing Message from the Birds
The
majority of the
world’s bird species are
found in South
America.
Threatened with habitat
loss and invasive
species.
Flyways
Migration
pathways used by birds moving
from southern wintering ground to northern
breeding grounds.
Tend to follow 4 major pathways, along
coasts, mountain ranges, and major river
valleys.
Flyway City- major urban area located within
a flyway that breaks the connecting natural
habitats and can create impassable barriers.
Flyway Cities Coalition
Creating connected areas of habitat to help wildlife adjust to
habitat fragmentation
www.flywaycities.org
(creating landscapes that provide food, cover and water needed
for wildlife; ensuring native plants thrive)
Migratory Bird Hunting and Conservation Stamp Act (1934) The "Duck Stamp Act; requires each waterfowl hunter 16 years of
age or older to possess a valid Federal hunting stamp.
Human Impacts on Biodiversity
Introduction and invasion of
nonnative species
Most arrive to aquatic
areas in the ballast of
ships that discharged
water in arrival ports
*Solutions: discharge at
sea, sterilize or pump
nitrogen into ballast water
before dispersion
- Release of exotic pets
*Alligator and Burmese
python– Everglades
Lake Victoria, E. Africa - cichlids and Nile perch
Perch deliberately introduce to stimulate local
economy and fishing industry
* Declining cichlid pops. led to increase in
poverty and malnutrition (cichlids cheaper),
eutrophication of the lake algal blooms,
invasion of water hyacinth with block sunlight
and leads to oxygen deprivation
Perch– large,
carnivorous
Cichlids –
algae eaters
Characteristics of
Successful
Invader Species
• High reproductive rate,
short generation time
(r-selected species)
• Pioneer species
• Long lived
Characteristics of
Ecosystems Vulnerable
to Invader Species
• Climate similar to
habitat of invader
• Absence of predators
on invading species
• Early successional
systems
• High dispersal rate
• Release growth-inhibiting
chemicals into soil
• Low diversity of
native species
• Absence of fire
• Generalists
• High genetic variability
• Disturbed by human
activities
Fig. 11-13, p. 236
INVASIVE SPECIES
Many
Kudzu vine was introduced in
the southeastern U.S. to
control erosion. It has taken
over native species habitats.
OBJ 12.6
nonnative
species provide us
with food, medicine,
and other benefits
but a a few can wipe
out native species,
disrupt ecosystems,
and cause large
economic losses.
INVASIVE SPECIES
Many
invasive species have been introduced
intentionally.
OBJ 12.7
INVASIVE SPECIES
Many
invasive species have been introduced
unintentionally.
Great Lakes- zebra mussels (invasive species)
Interactive map showing progression of zebra mussel
populations from 1988-2008 (scroll over dates to see
distribution)
OBJ 12.8
INVASIVE
SPECIES
Prevention
is the
best way to reduce
threats from
invasive species,
because once they
arrive it is almost
impossible to slow
their spread.
Figure 11-13
Overharvesting
Loss of fish species due to
overfishing - ¾ of
commercially valuable
marine fish species are
overfished or fished near
limits
Commercial Extinctiondepletion of a commercially
valuable resource (ie. Specific
species of fish like N. Atlantic cod)
to a level at which it is no longer
valuable to harvest it and the pop.
may never recover.
Bycatch- non-targeted species caught on
fishing hooks and nets (ie. Long lining and sharks
or turtles)
1989: US enforces law that all
shrimp trawlers must include
turtle exclusion devices (TED’s)
Overharvesting/ Overexploitation
Some
protected species are killed for their
valuable parts or are sold live to collectors.
Killing predators and pests that bother us or
cause economic losses threatens some
species with premature extinction.
Legal and illegal trade in wildlife species
used as pets or for decorative purposes
threatens some species with extinction.
OVEREXPLOITATION
Rhinoceros
are often
killed for their horns
and sold illegally on
the black market for
decorative and
medicinal purposes.
Case Study:
Rising Demand for Bushmeat in
Africa
Bushmeat
hunting has
caused the local
extinction of
many animals in
West Africa.
Can spread
disease such as
HIV/AIDS and
ebola virus.
Endangered Species
Because of
scarcity of
inspectors,
probably no more
than 1/10th of the
illegal wildlife trade
in the U.S. is
discovered.
“Gorillas in the Mist”
The Story of Dian Fossey
POPULATION GROWTH,
POLLUTION, AND CLIMATE
CHANGE
Population
growth, affluenza, and
pollution have promoted the premature
extinction of some species.
Projected climate change threatens a number
of species with premature extinction.
Pollution
Each year
pesticides:
Example of biomagnification of
DDT in an aquatic food chain.
Kill about 1/5th of the
U.S. honeybee
colonies.
67 million birds.
6 -14 million fish.
Threaten 1/5th of the
U.S.’s endangered
and threatened
species.
Biomagnification video
OBJ 12.9
PROTECTING WILD SPECIES:
Solutions???
LEGAL AND ECONOMIC
APPROACHES
CITES.
International
treaties have helped reduce the
international trade of endangered and
threatened species, but enforcement is
difficult.
One of the most powerful is the 1975 Convention
on International Trade of Endangered Species
(CITES).
• Signed by 169 countries, lists 900 species that cannot
be commercially traded.
OBJ 12.10
The U.S. Endangered Species Act
One
of the world’s most far-reaching and
controversial environmental laws is the
1973 U.S. Endangered Species Act (ESA).
ESA forbids federal agencies (besides defense
department) to carry out / fund projects that
would jeopardize an endangered species.
ESA makes it illegal for Americans to engage in
commerce associated with or hunt / kill / collect
endangered or threatened species.
The U.S. Endangered Species Act
Biodiversity
hotspots in relation to the largest
concentrations of rare and potentially
endangered species in the U.S.
Lacey Act 1900
Prohibits
transporting live or dead animals or
their parts across state lines without a federal
permit. (US law)
PROTECTING WILD SPECIES:
THE SANCTUARY APPROACH
The
U.S. has set aside 544
federal refuges for wildlife,
but many refuges are
suffering from environmental
degradation.
Pelican Island was the
nation’s first wildlife refuge.
THE SANCTUARY APPROACH
Gene
banks, botanical gardens and using
farms to raise threatened species can help
prevent extinction, but these options lack
funding and storage space.
Zoos and aquariums can help protect
endangered animal species by preserving
some individuals with the long-term goal of
reintroduction, but suffer from lack of space
and money.
Protecting and Sustaining Marine
Biodiversity
Problems:
Jurisdiction in
regulation of open
seas?
Tragedy of the
Commons- much of
the damage is not
noticeable to most
people; ocean is an
inexhaustible resource
Solutions:
Establish laws and
international treaties
• CITES, EPA, US
Marine Mammal
Protection Act, US
Whale Conservation
and Protection Act, etc.
Education
U.S. Coastal Waters
Pew Oceans Commission conducted a 3 year study
which determined our coastal waters were in deep
trouble and laws needed to be reformed in order to
protect them.
Recommendations included:
1) Pass a Natl. Ocean Policy Act that commits the country to
sustain, protect, and restore oceans.
2) Double fed. Budget for ocean research
3) Fishery management based on preserving aquatic
ecosystems rather than catch limits for certain fish species.
4) set up a network of marine reserves (like terrestrial
biophere reserves) with protected corridors linking reserves
to help protect fish breeding and nursery grounds.
Commercial Whaling
Cetaceans (marine mammals ranging from 3-100
ft; toothed and baleen whales)
Intl. Whaling Commission (IWC- 1946) – 49
nations to regulate the whaling quotas to prevent
overharvesting
1970 : US banned whaling and imports of whale
products
1986: IWC imposed moratorium on commercial whaling;
some countries like Japan, Norway, and Iceland still hunt
specific species claiming they are used for “scientific
research” purposes.
Commercial Whaling industry
Info on Japanese whaling (IWC and scientific permits)
International Agreements
Coastal countries control up to 12 miles
offshore, fishing allowed up to 230 miles
(beyond any country jurisdiction is known as
High Seas)
Marine Protected Areas (MPA’s)- areas of the
ocean protected by some or all human
activities (1300 MPA’s provide protection for 0.2% of earth’s
total oceans)
Marine Reserves- fully protected areas and
no extraction of any living or nonliving
resource is allowed. (90 of 350 biosphere reserves are
coastal or marine habitats)
Marine Protected Areas
Marine Reserves
Integrated Coastal Management
Community
effort to develop and use coastal
resources more sustainably.
Goal is to increase zoning of marine reserves
and protected areas; Hard to enforce
Integrated Coastal Management
and Reconciliation Ecology
Red Sea Star Restaurant, Israel: restored coral
reef and tourist attraction! ($ and environmental
purpose!)
Protecting, Sustaining and Restoring
Wetlands
CERP (Comprehensive Everglades Restoration Plan)one of the world’s largest ecological restoration project
Flow maps
Surface Water Storage Reservoirs
Water Preserve Areas
Management of Lake Okeechobee as an
Ecological Resource
Improved Water Deliveries to the Estuaries
Underground Water Storage
Treatment Wetlands
Improved Water Deliveries to the Everglades
Removal of Barriers to Sheetflow
Storage of Water in Existing Quarries
Reuse of Wastewater
Improved Water Conservation
Additional Feasibility Studies
13-6 Protecting, Sustaining, and Restoring Lakes & Rivers
Pacific Salmon – construction of dams (Great animation of similar
human impacts on Atlantic salmon!)
Fish ladder- help reestablish salmon
migration path for breeding
Sustainability of Aquatic
Ecosystems
Increase
research of aquatic life
Expand efforts to protect and restore
(US National Wild and Scenic Rivers
System)
Incorporate more integrated ecological
management between terrestrial and
aquatic ecosystems
RECONCILIATION ECOLOGY
Reconciliation
ecology involves finding ways
to share places we dominate with other
species.
Replacing monoculture grasses with native
species.
Maintaining habitats for insect eating bats can
keep down unwanted insects.
Reduction and elimination of pesticides to protect
non-target organisms (such as vital insect
pollinators).
Using Reconciliation Ecology to
Protect Bluebirds
Putting
up bluebird
boxes with holes too
small for (nonnative)
competitors in areas
where trees have
been cut down have
helped reestablish
populations.