Modes of Swimming: BCF + MPF

Question 1

Define anguilliform swimming. Give an example

Answer 1

• whole body flexion
• eels/lamprey/lungfish

Question 2

Anguilliform swimming is assumed inefficient but:

Answer 2

• eels have cost of transport 4-5x less than salmonids

Question 3

What kind of spawning migration do eels have? What other fish swim like this? when?

Answer 3

• 5k w/o eating (need to be efficient)
• sharks/teleosts at slow speeds

Question 4

define sub-carangiform swimming

Answer 4

• undulation of posterior 1/3-1/2 of body (caudal fin!)

Question 5

What fish use sub-carangiform swimming?

Answer 5

• rover-predators such as salmon + bass
• shallow undulatory movement

Question 6

What is the AR of fish that use sub-carangiform swimming?

Answer 6

• 1-3 in bass and trout
• relatively slow moving and fusiform

Question 7

Define carangiform swimming

Answer 7

• undulation of posterior 1/3 of body (caudal peduncle + fin)

Question 8

What fish use carangiform swimming?

Answer 8

• jacks, tuna, mackerel

Question 9

Amplitude of waves ____ anterior to tail in carangiform swimmers

Answer 9

• increases
  (rest of body stable)

Question 10

In carangiform swimmers, what do finlets do?

Answer 10

• decrease turbulence

Question 11

What does the narrow caudal peduncle act as in carangiform swimmers?

Answer 11

keel

Question 12

Lunate caudal fin has ____ AR. Why?

Answer 12

• high
• small SA : max propulsion force, less waste in lat movement (efficient)

Question 13

Define thunniform swimming

Answer 13

• oscillation of tail
• fast efficient cruising speeds

Question 14

What fish use thunniform swimming

Answer 14

• billfish and lamnid sharks (INDEPENDENT convergent evolution)

Question 15

What are the physical attributes of thunniform swimmers?

Answer 15

• low drag (high Re) - fast+large
• lunate caudal fin

Question 16

What does the lunate caudal fin do for thunniform swimmers?

Answer 16

• high AR = maximizes propulsion and minimizes vortex drag

Question 17

What is the AR of thunniform fish?

Answer 17

10

Question 18

Define ostraciform swimming

Answer 18

• sculling with caudal fin (low velocity swimming

Question 19

What kind of fish are ostraciform swimmers

Answer 19

• boxfish (poor/slow swimmers)

Question 20

What are the physical attributes of ostraciform swimmers

Answer 20

• isocercal caudal fin (low AR)
• slow -> rely on spines/armour for protection

Question 21

What does MPF mean?

Answer 21

median or paired fins

Question 22

Define labriform swimming

Answer 22

• rowing/flapping of pectoral fins (propulsion/maneuvering)

Question 23

What kind of fish use labriform swimming and where do they usually reside?

Answer 23

• parrotfish
• coral reefs, dense vegetation

Question 24

Define rajiform swimming

Answer 24

• undulatory waves using enlarged pectoral fins/medial fins

Question 25

What fish use rajiform pectoral swimming

Answer 25

• skates/rays

Question 26

What fish use rajiform medial fins?

Answer 26

• knife and triggerfish

Question 27

What rajiform fin is more efficient

Answer 27

medial fin, backward/fwd movement efficient

Question 28

What % of fish use BCF propulsion?

Answer 28

• 85%

Question 29

What % of fish use MPF propulsion?

Answer 29

• 15%

Question 30

MPF is used more for ___ and ____ than propulsion.

Answer 30

• maneuvering and stabilization