What is nekton? Indicate the major taxonomic groups, and the stages of their life-history, that are commonly represented in marine nekton. Outline the trophic roles of marine nekton.

Question 1

What is meant by the term nekton?

Answer 1

Nekton- organisms living in the water column with swimming abilities that allow them to move actively through the water and against currents.

Question 2

What is the taxonomic composition of nekton?

Answer 2

• The nekton is strictly an animal group
• Mainly vertebrates (since they typically have relatively good mobility)
• Range of fishes and secondarily marine invertebrates
• Also includes the pelagic cephalopods
• Plus a range of other invertebrates that are borderline between nekton and plankton

Question 3

What are the main life stages of nekton?

Answer 3

• Mainly juveniles and adults
• Secondarily marine invertebrates- born or enter the water at a relatively advanced stage of development
• Pelagic sharks- give birth to live young at advanced stage of development
• Typically have complex life cycles, size and mobility of individuals increases during development, early life stages are planktonic/ later life stages are nekton

Question 4

What is the trophic role of nekton?

Answer 4

• Consumers

o Mainly carnivores and mainly predators (upper levels of the food web)