Marine Mammals Flashcards
1
Q
Give the kingdom phylum, and class of all marine mammals
A
kingdom animalia, phylum chordata, class mammalia
2
Q
What are the 6 things that define being a part of class mammalia?
A
- possess mammary glands (milk)
- warm blooded
- viviparous (baby develops internally with placenta and is born live to feed off mother)
- have body hair (exception of cetaceans)
- specialized teeth
- air breathing vertebrates
3
Q
How do marine mammals breathe?
A
- respiratory system designed for breathing atmospheric oxygen
- some have blowholes (1 - tooth whales, 2 - baleen whales);
> keeps body in the water and reduces exposure to air/predators
4
Q
How have marine mammals evolved over time?
A
- mammals evolved after dinosaurs died off
- too much competition for land food so they took to feeding in the water; eventually their legs modified into flippers
- e.g walking whale (ambulocetus natans)
5
Q
Examples of marine mammals in the order cetacea
A
- whales, dolphins, porpoises
- largest is blue whale (100ft)
- smallest is dolphin/porpoise (6ft)
6
Q
What classifies the sub-order odontoceti
A
- toothed whales
- peg/spade-like teeth for grabbing fish (swallow fish whole)
- eat squid, fish, and fast moving prey
- largest is sperm whale
- use echolocation:
> pulses or clicks to locate food or stun prey; low frequencies for general environment, high frequencies for details
> noise produced by nasal sacks and focused by melon (above upper jaw)
7
Q
Give and explain two animals in the sub-order odontoceti
A
- Sperm whale
> largest toothed animal (67ft)
> hunt giant squid at great depths
> stun prey with sonic blast (massive melon) - Narwhal
> 26ft long (males have a long spiral tusk up to 10 feet growing out of their upper jaw used to attract females and fend off rival males)
8
Q
What classifies the sub-order mysticeti
A
- baleen whales
> eg blue, humpback, finback
> overlapping plates of keratin that grow from upper jaw (giant comb/brush)
> gulp water and push it back out with tongue to filter and capture small organisms
9
Q
In the order carnivora, what classifies the sub-order pinnipedia?
A
- eg. seals, sea lions, walruses
- “feather footed”
- most return to shore to rest and breed
- functional hind limbs
- excellent swimmers due to strong fore or hind flippers
- largest is elephant seal 23ft
10
Q
Differences between seals and sea lions
A
- sea lions have long necks and seals have short necks
- sea lions hind flippers can be moved forward, and a seals cannot
- sea lions use their front flippers for swimming where seals use their hind flippers
- front flippers of a sea lion can support its body weight where a seals cannot
- sea lions have external ear flaps
- sea lions have external tested and seals have internal testes
11
Q
Name and give examples for the three families in the sub-order pinnipedia
A
- family otaridea
> sea lions, fur seals - family phocidae
> grey seals, harbor seals, elephant seals (true seals) - family odobenidae
> walrus (distinctive by tusks used for defense or to hold onto ice flows)
12
Q
what classifies the order sirenia
A
- front flippers but no rear flippers
- swim with up and down strokes of a paddle shaped tail
- padded with blubber and thick skin
- live in groups
- herbivores
- 4 species remaining (endangered by boats and jet skis)
13
Q
Describe the killer whale
A
- orcinus orca
- largest member of dolphin family; up to 8000lbs and 26ft long
- live in oceans near equator/north or south pole in groups called pods
- resident pods are less aggressive and occur in larger numbers
- transient pods are aggressive and smaller
- apex predator (top of food chain)
- feed on everything
14
Q
Protection of marine mammals
A
- IWC; regulates whale hunting and overfishing but missed key nations
- marine mammal protection act; bans hunting and killing of all marine mammals in us waters
