Threats to Streams - Invasive Species - final exam questions

These flashcards cover major topics discussed in the lecture on threats to streams, focusing on invasive species and their impacts on freshwater biodiversity.

What are the five major threat categories to freshwater biodiversity?

Over-exploitation, Water pollution, Flow modification, Species invasion, Habitat degradation.

What is an invasive species?

A non-native or non-indigenous species that is abundant and causes harm to natural communities.

Why have exotic species become more common in freshwater environments?

Aquatic habitats have been highly modified, introductions have been frequent, and there is high connectivity.

What is the ballast water cycle?

The process of taking in and discharging water ballast during cargo transport, which can introduce non-native species.

What major factor influences a species' relationship with humans?

Whether the species is desirable or beneficial to humans.

What are some groups of fish that have a positive relationship with humans?

Cyprinidae (carps and minnows), Ictaluridae (catfish), Salmonidae (salmon, trout), Centrarchidae (sunfish), Cichlidae (tilapia, angelfish).

What traits influence the success of an invasive species?

The traits of the invading species and the traits of the environment.

What is the concern regarding the introduction of non-native fish?

They can have drastic impacts on local ecosystems and populations of native species.

What notable invasive species is highlighted in U.S. streams?

Dreissena polymorpha, also known as the zebra mussel.

What are the predicted consequences of increasing invasive species in native mussel populations?

Models predict large increases in extinctions of native mussels.

What historical context is presented about common carp in the U.S.?

Common carp was deemed useful and nutritious, being marketed in large quantities since its introduction.

Name some invasive carp species that are currently of most concern.

Silver carp (Hypophthalmichthys molitrix) and Bighead carp (Hypophthalmichthys nobilis).