Invasive Species and Biodiversity Notes

Species that are not native to an area and are often introduced by human transport.
Common attributes of invasive species:
  - Generalist species that are r-selected.
  - Lack of natural predators leading to uncontrolled population growth.
  - High biotic potential paired with low parental care.
  - Variety of habitat and food needs, showcasing adaptability.
  - Highly competitive nature, which includes aggressive feeding behaviors or rapid growth fostering resource competition.

Description: Aggressive filter feeders that exploit algae, crucial for many native species.
Impact:
  - Clogs intake pipes.
  - Reproduces at approximately 1 million eggs per year.
  - Originally planted to limit soil erosion in the southern U.S.
  - Detrimental to sunlight penetration for native species.
  - Lacks herbivore control in the U.S.

Impact:
- Rapid growth causing outcompeting of native vegetation for sunlight.
- Transported via ship ballast water leading to its spread.

Origin: Introduced to control algae in aquatic farms.
Impact:
- Escaped into the Mississippi River, where it now competes with native fish species for food and space.
- Results in decreased fishery production and economic value.

Origin: Released in Florida, initially kept as pets.
Impact:
- Larvae bore into tree bark, disrupting nutrient transport and ultimately killing trees.
- Spread via wood packing materials and firewood.

Cane Toad: Introduced to control cane beetles in Australia; became invasive due to high appetite, decimating mammal populations in the Everglades (90-95% decline).
Impact: Expanding range attributed to global warming with severe consequences for other amphibians and small reptiles.

Estimated cost to the U.S. economy is approximately $120 billion annually (as of 2005).

Control Strategies:
  - Laws are implemented to prevent transportation of invasive species (e.g., banning firewood transport to slow Emerald Ash Borer spread).
  - Removal methods include:
    - Elimination of host species (e.g., dead ash trees).
    - Introduction of biological controls as natural predators (e.g., Chinese wasps introduced to combat the emerald ash borer).
    - Maintenance of boating equipment which involves cleaning and inspecting boats to limit zebra mussel spread.
    - Physical removal methods like hunting invasive pythons, detaching zebra mussels, and cutting down invasive plants.

Human Influences:
  - Poaching for exotic goods (fur, tusks).
  - Removal from natural habitats for sale as pets.
  - Specific habitat or dietary requirements make species vulnerable.
Environmental Changes:
- Climate change causes habitat shifts, complicating migration and adaptation options.
- Agriculture and urbanization contribute to habitat fragmentation.
Invasive Species: Outcompete native species for resources, leading to declines (e.g., zebra mussels harming native mussels).

Preventing Poaching:
  - Employment of armed guards to deter poaching.
  - Legal protections through designated areas: national parks, wildlife preserves.
  - Laws aimed at reducing hunting and habitat destruction.
Wildlife Legislation:
- CITES provides guidelines for monitoring endangered species trade.
- The Endangered Species Act empowers the U.S. Fish and Wildlife Service (USFWS) to manage species at risk.

Endangerment by Taxon:
  - Amphibians: 41% at risk.
  - Mammals: 25% at risk.
  - Birds: 13% at risk.
Vulnerability Factors:
- Climate change impacts coral species.
- Threatened by disease and warming temperatures.

Specialists: Less likely to adapt to new conditions, prone to extinction under rapid changes.
Generalists: Better adaptability increases survival under various environmental changes, making them less threatened.

Interspecific Competition: Competition among different species can lead to threats, especially with general habitat loss. Example: Shenandoah salamander (endangered) versus red-backed salamander (least concern).

HIPPCO: Represents main factors affecting biodiversity:
- Habitat destruction, Invasive species, Population growth, Pollution, Climate change, Over-exploitation.

Causes: Construction (roads, pipelines), agricultural expansion, and logging activities.
Impacts: Fragmentation adversely affects ecosystems and species populations differently.

Warming temperatures can cause habitat shifts, impacting flora and fauna distribution. Changes in precipitation patterns may also lead to habitat loss.

Crops: Over-reliance on few species through selective breeding reduces overall genetic diversity, thereby increasing vulnerability.
Livestock Domestication: Leads to losses in genetic diversity among breeds, threatening agricultural resilience.

Creating protected areas like parks, wildlife preserves, and habitat corridors to facilitate species movement and reproduction.
Adopting sustainable agricultural practices to reduce habitat loss and biodiversity degradation.
Initiatives to restore lost habitats through replanting and other rehabilitation efforts.

FRQ 9.10: Discuss the pros and cons associated with preserving land as wildlife reserves.