Lecture 13 & 14 - Marine Mammals

Question 1

Give six key points on marine mammals

Answer 1

> Veterbre, well developed CNS and brain + potential 2 way communication
Warm blooded - homoeostatic control, maintenance of core temp
Give birth to live young
Feeds young with milk from mammary glands (wheening)
Breath air (adaptations)
Epidermis with hair (may be reduced)

Question 2

Give four adaptations of marine mammals

Answer 2

> Swim, including diving for long peroids to depths
Control their core body temp
Come to the surface to breath air
Give birth to live young and suckle them

Adaptations between organisms vary greatly from mammal to mammal

Question 3

Give the four orders of marine mammals and some examples

Answer 3

> Pinnipeds - seal, fur seals, walruses
Carnivora - Polar bear, sea otter
Sirenians - Manatees and dugong
Ceatceans - Whales and Dolphins

Question 4

What is the name for seals in latin and of which family is it from? how many types are there

Answer 4

Name = Phocidae (seals)
Family = Pinnipeds
18 types

Question 5

4 key features of a Phocidae

Answer 5

> Internal ear with no external features
Clawed front flippers
Walk only on front flippers
Swim with hind flippers

Question 6

Explain the distributions of Phocidae and the two key environments and associated risks

Answer 6

Mainly polar!
>Arctic seals - have a greater range of threats from humans (fishing) and predation (killer whales)
>Antarctic seals - Reduced predation (leapord seal) and reduced effects from us (pollution reduced etc..)

Question 7

What are the two warm species of seals

Answer 7

Med monk seal

Hawian monk seal

Question 8

What are adaptations of phocidae to temperatures

Answer 8

> Blubber, high insulating and rich source of energy (wheening)
Caoillaries in blubber and skin constrict (vasoconstriction) to reduce blood flow to periphery

Question 9

Explain the diving ability of seals

Answer 9

Can hold their breath for ages due to high oxygen store in body tissues as well as Bradychardua - which is slowing of the heart, cardiac output reduced by 20%

Question 10

What is the important of lactate dehydrogenase

Answer 10

It stops of the build up of toxins due to lack of oxygen ( why muscles ache )

Question 11

Explain reproduction in phocidae

Answer 11

I stud can mate with 30/40 through sexual reproduction (nice). Give birth on land and young develop real quick. Feed young from mammary glad which is 40 -50% fat.

Question 12

How can wheening depend on other biotic factors

Answer 12

If they are prime pray for killer whale / leapord sea then they will wheen quicker

Question 13

Name the 6 types of Arctic seals (fuck the latin names)

Answer 13

Ringed
Bearded
Harp
Hooded
Spotted
Ribbon

Question 14

Name the 4 types of antartic seals (no latin names)

Answer 14

Crabeater
Weddell
Lepoard
Ross

Question 15

What do seals feed upon in the arctic

Answer 15

Mostly fish (mainly cod) shrimps and squid, bearded seal feeds on benthic organisms

Question 16

What do seals feed on in the antarctic

Answer 16

Apart from the leopard seal (apex) feed on krill. Lepoard seal feeds upon smaller seals and fish

Question 17

What is special to the crab eater seal

Answer 17

It has specially adapted teeth (most special in marine) which is a series of fine spites for sieving out krill

Question 18

What is the difference from fur seals to seals (3)

Answer 18

> Ears extend out of the head
Front flippers are longer and used for swimming
Can walk on land using both rear and front flippers

Question 19

What are the differences between sea lions and fur seals (2)

Answer 19

Sea lion = rounded snout, short fur

Fur Seals = Long snout, long fur