Intruders In An Ecosystem Flashcards
Why are New Zealand’s species unique compared to other parts of the world?
New Zealand became isolated from other land areas 66 million years ago, allowing unique species to develop.
What were the characteristics of native birds in New Zealand before humans arrived?
Many birds nested on the ground and had no predators to eat their eggs or young. Some, like the kiwi, couldn’t fly.
When did humans first arrive in New Zealand, and what species did they bring?
Humans arrived about 700 years ago, bringing animals like rats on boats and later introducing sheep, rabbits, and stoats.
How did introduced species affect New Zealand’s native birds?
Rats and stoats became predators, eating eggs, chicks, and even adult birds. This caused several bird species, such as the laughing owl, to go extinct.
Why were stoats introduced to New Zealand, and what has been their impact?
Stoats were introduced to control rabbits, but they became a threat, killing birds and eating 60% of kiwi chicks.
What challenges do New Zealanders face in eradicating stoats?
Stoats breed rapidly, making it very difficult to completely eliminate them. Controlling their population is the best option.
How many native bird species in New Zealand have gone extinct since humans arrived, and why?
53 species have gone extinct, mainly due to hunting and the introduction of invasive species like rats and stoats.
What is a native species?
A native species is an organism that naturally lives and thrives in a specific region or ecosystem without human introduction.
Why is it difficult to eradicate an introduced species once it settles in a new area?
Introduced species can adapt to the new environment, reproduce rapidly, and may lack natural predators to control their population.
Why are stoats a problem in New Zealand but not in their native habitat in Europe?
In New Zealand, stoats face fewer predators and have access to vulnerable prey like native birds, unlike in Europe, where they are part of a balanced ecosystem.
What is the name for a plant that grows in an ecosystem where it does not belong?
An invasive species.
What is buffelgrass, and how did it come to Arizona?
Buffelgrass is a plant native to Africa, Asia, and the Middle East. It was introduced to Arizona in the 1930s as cattle fodder and has since spread rapidly.
How does buffelgrass impact the Sonoran Desert ecosystem?
Buffelgrass grows in dense patches, taking water and nutrients from the soil, which could harm native species by outcompeting them for resources.
