biodiversity and hawaii

a case study examination

what is biodiversity?

•at ecosystem level: the number of biomes in a given region

•at organism level: the number of species in a given area

•in terms of genetics: number of alleles in a population

•can also be thought of in terms of evenness.

is biodiversity in danger?

• biodiversity is threatened by the disruptions to the natural ecosystem that limit the resources needed by an organism (light, food, water, space) or alter how that organism interacts with other organisms (predation, competition.)

• Disruptions of this sort are caused by two things:

• 1. establishment of exotic, or introduced

species.

• 2. habitat fragmentation

is biodiversity in danger?

• introduced species

• species brought to an area either intentionally or by accident that are not naturally part of the ecosystem

• most fail to survive, however, some...

• thrive and out-compete native species

• prey on native species

• transmit exotic diseases

• facilitate the spread of native diseases

• hybridize with natives

• alter habitats

is biodiversity in danger?

• habitat fragmentation

• when people alter natural areas through actions, like agricultural or urban sprawl, the habitats needed to sustain native species are often eliminated, and he remaining natural areas are left isolated.

• extremely concerning to conservation biologists; habitat fragmentation does not only result in a loss of habitat, but also genetic exchange amongst the broken up populations

•How do you measure biodiversity?

Indicator species and biotic indices (G.4.1)

Indicator species are extremely sensitive to environmental changes, and their populations fluctuate greatly depending on environmental changes; these prove to be good indicators of change. Frog populations are quite vulnerable to pollution and other forms of change, while sludge worms are good indicators of low oxygen concentration in waterways.

Biotic indices are calculated via the number of tolerant and intolerant species at a time. The numbers of these organisms in the indicator species populations are monitored over time directly so it is easy to keep track of them.

•Often times, new species are introduced to different areas for agricultural use (cows, goats, etc) , and it is not uncommon for these domesticated animals to become feral. Because of this, what role do humans play in the threat to biodiversity?

What leads to extinction?

(G.4.2)

• DODO BIRD (Origin: Mauritius)

• Eaten by Dutch sailors who first discovered them (1600s)

• Destruction of forest by settlers (loss of food supply)

• Dodo nests destroyed by sailor’s animals, including: rats, cats, and pigs

•What are humans doing to conserve biodiversity?

Biogeographical features promote conservation (G.4.3)

• Large nature reserves usually promote conservation of biodiversity more effectively than small ones. The ecology of the edges of ecosystems is different from the central areas due to edge effects and its increase for the risk of predation. An example of an edge effect is the egg-laying habits of the cowbird of the western United States. It feeds in open areas, but it lays its eggs in the nests of other birds near the edges of forests. Fragmentation of forests has led to a considerable increase in cowbird populations because of the increase in forest edge. Wildlife corridors allow organisms to move between different parts of a fragmented habitat, for example, tunnels under busy roads.

Active Management Techniques in Conservation

(G.4.4)• Active Management Techniques:

• Adaptive Management: A system used by large organizations to manage geographically and/or habitat diverse conservation projects. Includes digitization of records and the tracking of changes in human, animal, plant and weather activities and update central databases. The intention of adaptive management is to create conservation policies that have the largest impact on a multitude of issues by utilizing the most current data.

• Ecosystem Management: A conservation practice that lets conservations within a particular field compare and argue their conservation plans. Ideas are discussed in a forum-like setting; not all ecosystem will come to a consensus. The United States Forest Service has adopted ecosystem management practices as its official policy for managing national forests.

• Agroecosystems Analysis: Requires sustainable solutions that can merge with the conservation efforts of sustainable environmental, socio-economic, and urban development systems. This type of analysis attempts to classify agricultural activities by region and resource needs. Example: determining how a large farm and an urban center in close proximity can work together to conserve water and minimize their collective environmental impact.

• Soft Systems Analysis: A method of conservation that uses words, diagrams and images to explain complex conservation ideas and techniques across disciplines. This gives the multiple groups working together (government/private agencies) a common language in which management activities and goals can be discussed. Multiple perspectives are valued in this type of analysis since the more comprehensive and inclusive communication is, the more effective are the outcomes.

In situ Conservation

• In situ conservation: the conservation of species where they are found naturally.ie: Nature reserves and/or national parks

• Advantages include: Access to all of its familiar resources (will not have to adapt to new diet or fake environments), species will continue to evolve in their natural environment, more space, bigger breeding populations can be kept in situ, and it costs less to keep an organism in situ.

• Disadvantages: Difficult to control illegal exploitation and environment may need to be restored

Ex situ Conservation

•Ex situ: animals maintained in zoos or wild life parks, especially when not in original geographic zone.

•Captive Breeding of animals:

•captive breeding of endangered animals is a last resort; it is only used if a species has no chance of recovering in the wild.

•Works well for species that are bred easily in captivity, like geese and deer; however, more specialized species are difficult to maintain.

•Animals isolated in captivity do not evolve with their environment

•Small gene pool: inbreeding, invitro fertilization utilized.

•Possible to restore a population in captivity, however, it may have disappeared in the wild.

Ex situ Conservation

•Botanical Gardens:

•Limited range of species

•Distribution of botanical gardens reflects the distribution of colonial powers; Most found in Europe and North America. Plant diversity is greatest in the tropics.

•Seed Banks:

•Seeds can be maintained for decades or centuries in controlled conditions•Seeds need to be germinated regularly in order to renew stock; otherwise, seeds will lose viability

•Seed banks are at risk from power failure, natural disasters, and war.•Duplicate stocks can be maintained•Seeds that are kept in seed banks do not evolve with environment changes.

Sources

•http://www.pbs.org/wnet/nature/episodes/kilauea-mountain-of-fire/hawaiis-vulnerable-biodiversity/4838/

•http://www.amnh.org/exhibitions/expeditions/treasure_fossil/Treasures/Dodo/dodo.html?dinos

•http://www.ehow.com/list_6861965_active-management-techniques-conservation.html