Environmental Unit 4
Protected area consisting of ones that vary in the amount of permissible human impact
Biosphere Reserve
iii. Describe ways to reverse these trends and prevent extinction.
1. Protection of endangered species through legislation 2. Habitat Protection(reserves, other areas) 3. Reduce invasive species introduction - inspection of goods entering countries, prohibition of wooden packing crates 4. Removal of invasive species
b. In recent times - Human-caused extinction i. List at least 4 ways humans cause extinctions. ii. Identify the most significant cause.
1. habitat alteration and destruction - most significant 2. hunting or harvesting 3. pollution of habitat 4. introduction of exotic species
spends most of its life in the sea and returns to freshwater to spawn
Anadromous Fish
Explain edge effect in relation to ecosystem boundaries and give an example.
At the border of one ecosystem, changes occur that affect not just the exact border, but have effects a distance into the ecosystem (border of a forest for example)
- International agreement signed by 80 countries that regulates the trade of species at risk including live animals and plants, and products used for food, leather, wood, curios, and medicines. - As of 2005 169 countries have at least accepted this treaty. - No enforceable powers
CITES (Convention on International Trade in Endangered Species)
specific geographic areas that contain features essential to the conservation of an endangered or threatened species and that may require special management and protection
Critical Habitat
Explain the decline in genetic diversity in both wild and domestic species and the consequences of each.
Decline in populations can lead to reductions in genetic diversity that cause inbreeding depression In domestic species, humans have focused on production and many varieties have disappeared
A particular location on Earth with interacting biotic and abiotic components
Ecosystem
Habitat that occurs where two different communities come together, typically forming an abrupt transition, such as where a grassy field meets a forest
Edge Habitat
- Adequate and appropriate habitat must be provided for each endangered species. - It is illegal to trade in endangered species or products made from them. - It is illegal to harass, harm, or capture an endangered species or destroy its habitat - Each endangered species must have a recovery plan
Endangered Species Act
A species that is in danger of extinction within the foreseeable future throughout all or a significant portion of its range
Endangered species
A species living outside its historical range
Exotic (or Alien) Species
The death of the last member of a species
Extinction
describing the complete process by which habitat loss results in the division of large, continuous habitats into a greater number of smaller patches of lower total area, isolated from each other by a matrix of dissimilar habitats
Habitat Fragmentation
International Union for Conservation of Nature
IUCN
A species that spreads rapidly across large areas
Invasive Species
Explain how invasive or exotic species lead to a loss of biodiversity
Invasive species can spread rapidly cause the loss of native species through competition, predation, or spread of disease
How does climate change affect species diversity?
It alters the environmental conditions, leaving species unable to move to more hospitable conditions.
- Required restoration of birds & game to areas where they are extinct. - Requires a federal permit to transport live or dead animals or their body parts across state borders
Lacey Act
How does the size and shape of a designated wilderness area affect the amount of edge effect?
Larger size with least edges has less edge effect
Species that are widespread and abundant
Least Concern Species
5. Discuss the ways habitat loss leads to decreasing biodiversity.
Loss of habitat leads to smaller populations, which can then suffer from genetic diversity. It can prevent migration and cause negative species interactions
- Prohibits the killing of all marine mammals in the U.S. - Prohibits the import or export of any marine mammal body parts
Marine Mammal Protection Act
Species that live in their historical range, typically where they have lived for thousands or millions of years
Native Species
. List the findings of the Convention on Biological Diversity
On average, species at risk of extinction have moved closer to extinction • ¼ of all plant species are still threatened with extinction • Natural habitats are becoming smaller and more fragmented • Genetic diversity of crops and livestock is still declining • There is widespread loss of ecosystem function • The causes of biodiversity loss have either stayed the same or increased in intensity • The ecological footprint of humans has increased
Marine harvest peaked in 1989 and has since declined. What is the main cause for the decline in the worldwide fish harvest?
Overfishing
Why aren't rats an endangered species? (What characteristics do species like rats have that make them less likely to become endangered?)
Rats seem to be able to adapt to different habitats and we seem to be creating excellent alternative habitats for rats, so they thrive, despite our attempts to eliminate them. There are few natural predators for rats in urban settings
A list of worldwide threatened species
Red List
List at least 4 practices that have caused a decline in the harvest of fish from coral reefs. (You may have to look beyond the textbook)
Reefs are torn apart by fishing nets (drag nets or by the chains that pull the drag nets) • Killing or stunning fish with dynamite has destroyed reefs • Deforestation has increased soil erosion and sediment deposition in the ocean, smothering the coral. • Overuse of the reef by people snorkeling and taking small samples of coral has destroyed the reef.
Any species that is likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range
Threatened species
Why does most fishing take place over or near continental shelves
Upwelling currents supply the waters over or near continental shelves with nutrients which forms the basis for marine food chains
What have been the major causes of extinction: a. Before people existed on Earth?
a) Variations in the physical and biological environment b) Variations in population sizes c) Genetic drift d) Mutations e) Reduced genetic variation
a. Identify one threatened or endangered species and explain why its population has declined
a. The black rhino species in endangered due to habitat loss and poaching.
b. Describe three characteristics of organisms that would make them particularly vulnerable to extinction
b. Population risk- random variation in pop. birth rates and death rates. Env. risk- random variation in physical or biological environmental factors such food sources, predators, weather, symbionts. Genetic risk- low genetic diversity
c. Present three arguments in favor of the maintenance of biodiversity.
c. They play an important role in their habitats and in countries like Namibia, rhinos are an important source of income from ecotourism. The protection of black rhinos creates large blocks of land for conservation purposes. This benefits many other species, including elephants.
d. Name and describe one United States federal law AND one international treaty that is intended to prevent the extinction of species.
d. The Endangered Species act is an Act to provide for the conservation of endangered and threatened species of fish, wildlife, and plants, and for other purposes. The Convention on International Trade in Endangered Species establishes a system of import/export regulations to prevent the over-exploitation of plants and animals listed in three appendices to the Convention
Explain the benefits of taking an ecosystem approach, as opposed to a single-species approach, to conserving biodiversity.
• Concern with the entire community of organisms and all the renewable resources, so that policies developed for one species are not wasteful of other resources. • Recognizes the benefit of preserving particular regions of the world before they are gone (biodiversity hotspots) • Maintenance of the ecosystem of which the wildlife are a part, minimizing risk of irreversible change and long-term adverse effects as a result of use. • Continual monitoring, analysis, and assessment of the protected areas is also part of it.
Evaluation of populations is essential to their conservation. Age-structure diagrams are helpful in assessing wildlife populations, often giving more information than just an overall population size. What could it mean if you saw fewer and fewer of the older cohorts of a species such as tuna (that is being harvested as a food source)? What could be done to improve the situation?
• This is an early sign of over-exploitation • Limit the catch of that species by quotas, education, etc. • Establish no-fish zones that would be effective for that species, allowing it to recover.
List at least 3 of the problem fisheries.
• swordfish • codfish • salmon • tuna, • sharks