Lilly, et al 2023

Question 1

What were the speeds of Atlantic salmon smolts migrating in the Irish sea?

Answer 1

Ranging from 14.03 to 38.56 km per day

Question 2

What was a strong indicator for migration success?

Answer 2

Strongly correlated with the distance they had to travel

Question 3

What is the citation for this paper?

Answer 3

Lilly, et al 2023

Question 4

What is the name of this paper?

Answer 4

Migration patterns and navigation cues of Atlantic salmon post-smolts migrating from 12 rivers through coastal zones around the Irish sea

Question 5

What journal published this paper?

Answer 5

Journal of Fish Biology

Question 6

What did the results of this study strongly indicate about post-smolts migrating though the coastal marine environment?

Answer 6

-Not simply migrating by current following
-They engage in active directional swimming
-Have an intrinsic sense of their migration direction
-Can use cues other than water current direction to orientate during this part of there migration

Question 7

What makes migration beneficial?

Answer 7

-Fitness benefits
-Chance of acquiring resources out weigh cost of migration

Question 8

What are some costs associated with migration?

Answer 8

-Exposure to natural and anthropogenic stressors
-Predators
-Diseases
-Parasites
-Navigation error leading to mortality

Question 9

How much is known about marine navigational cues?

Answer 9

Very little is known

Question 10

Describe salmon migration

Answer 10

Atlantic salmon is an anadromous salmonid that spawns in fresh water and migrates to the sea for access to better feeding opportunities’

Question 11

What are the assumed benefits for Atlantic salmon migration?

Answer 11

-Higher fecundity for females
-Greater mating success in males
-Larger body size
-Faster growth at sea compared to freshwater

Question 12

How long do salmon spend in their natal streams?

Answer 12

-Spend 1 - 7 years

Question 13

Describe the downstream migration of Atlantic salmon

Answer 13

-Tends to be nocturnal
-Rapid
-During periods of high river discharge

Question 14

Why is it believed that nocturnal migration is advantageous?

Answer 14

-Decreases visual risk from predators

Question 15

When do smolts form UK and Irish rivers enter the estuarine environment?

Answer 15

Late April and May

Question 16

What is a post-smolt?

Answer 16

After entry to sea, until December 31st of the same year

Question 17

Why is an understanding of migratory pathways important?

Answer 17

-For correct management of anthropogenic coastal activity

Question 18

How many wild and ranched salmon were captured for this study?

Answer 18

1008 wild
60 ranched

Question 19

How many acoustic tags were deployed?

Answer 19

183

Question 20

What did the study find out about success rate of migration between different rivers?

Answer 20

The minimum migration success differed between rivers

Question 21

Why might this study not be completely representative?

Answer 21

Tagging is restricted by fish size, smaller fish cannot be tagged so no representative data for them

Question 22

What was the main finding of this study?

Answer 22

Minimum rate of success was lower for smolt that had to travel further
-6% for Nith smolts (278 km)
62% for River Bann smolts (46 km)
-Through Irish sea to the North Atlantic

Question 23

Why do smolts switch from nocturnal migration to day and night migration in the sea?

Answer 23

-Post smolts are visual predators
-Must feed in early stages of marine migration to reach destination