Power, et al 2023

Question 1

What is the name of this study?

Answer 1

Temporal shifts in the marine feeding of individual Atlantic salmon inferred from scale isotope ratios

Question 2

What is the citation of this paper?

Answer 2

Power, et al 2023

Question 3

What salmon were sampled in this study?

Answer 3

River Namsen salmon, Norway

Question 4

What were the main points of this study?

Answer 4

-As salmon increased in size, they reduced their feeding niche and specialised more
-Increased their dependency on higher tropic levels like fish
-Changes in isotopes showing consistent pattern of movement towards north and west between summer feeding periods

Question 5

What did study find out about the first fish to return?

Answer 5

They had the fastest specific growth rates at sea
-May be returning earlier to avoid being eaten by predators at sea

Question 6

Describe salmon feeding habits

Answer 6

-Huge diversity of feeding types
-Results in population resilience

Question 7

What role does diet play in salmon life cycles?

Answer 7

-Diet plasticity being linked to the ability of Atlantic salmon to survive and prosper in varying environments
-Differences in diets affect fitness-related traits such as body condition, parental quality and survival

Question 8

What type of feeders are Atlantic salmon?

Answer 8

-Are opportunistic feeders
-Prey dependent on spatial and temporal nature of feeding and body size

Question 9

What have differences in feeding been related to?

Answer 9

Linked to differences in migration timing

Question 10

What can stable isotopes in salmon scales reveal about their diet?

Answer 10

Vary in composition with variations in nutritional and maturation status

Question 11

How many salmon were sampled?

Answer 11

86

Question 12

What feeding shift is suggested?

Answer 12

That Atlantic salmon undergo a shift from generalist freshwater feeding to more specialized pelagic zone feeding in the marine environment

Question 13

What did 95% of the stomach contents of the returned fish?

Answer 13

-Sand eels
-Capelin
-Herring
-Haddock

Question 14

What behaviour do salmon participate in?

Answer 14

Feast and Famine
-Older groups had heavier stomach content that came at the expense of running empty more often.

Question 15

What did the study also find out in regards to smolts?

Answer 15

-Found that larger smolts did not feed at higher trophic levels compared to smaller smolts

Question 16

What do postsmolts mainly feed on?

Answer 16

-During early migration focus feeding on fish larvae and have diverse diet

Question 17

What journal published this paper?

Answer 17

Ecology and Evolution