6 Management

Management of Ecosystems

• Other factors that affect ecosystems

• Pest management

• Marine reserves

• Zoos

• Selective logging

Abiotic factors

• Temperature• Light• Substrate• Water currents• Trace elements• Pressure

Biotic

• Inter-specific relationships

• Intra-specific relationships

• Zonation• Straitifcation• Predator prey

relationships

Pest Management

• Biological control

• Physical methods

• Resistant strains

• Sterilisation

• Cultural control

• Introducing disease

• Chemical control

Biological Control

• Artificial control of pests or parasites using other organisms

• Must ensure only the target pest affected

• Will not wipe out a pest entirely

Physical Methods

• Traps• Homes built for

predators• Chop down invasive

creepers

Resistant Strains

• Breed plants resistant to rust and other fungi

• Graft plants onto resistant root stock

• Breed animals resistant to parasites

Sterilisation

• Male insects exposed to radiation

• Mate with female but no eggs develop

• Males caught in sticky trap, lured by female sex hormone

Cultural Control

• Alter feature of environment (destroy niche)– Drain swamp– Destroy crop

remains– Crop rotation

Introduce Disease

• Must be – Specific– transferable

• Often develop immunity

• Myxomatosis in rabbits

• Calcivirus in rabbits

Chemical Control

• Lay carrots or pellets of poison (1080, DDT, 2,4,5,T)

• Cyanide baits to kill rats, stoats, weasels

• Spray poisons (painted apple moth control)

Marine Reserves

• Areas of seabed and foreshore where no commercial fishing or shellfish gathering is allowed

• Managed by DOC• Contain viable

examples of ecosystems

• Large pristine natural areas

• Act as controls for measurement of management practices

• For scientific or recreational use

Reasons for Reserves

• Aesthetic• Recreational• Educational• Management• Breeding grounds• Protection of

species or habitat• Genetic

conservation

Zoo Breeding Programs

• Conservation of endangered species

• Raised to look after themselves then transferred to a predator free environment

Selective Logging

• Sustainable forest management

• Take only mature trees in such a way as the forest is as unaffected as possible