Marine Mammals - Aaron Purdy Flashcards
What groups comprise marine mammals – Aaron mentioned 5 ?
- Cetaceans (whales, dolphins, porpoises)
- Pinnipeds (otariids & phocids)
- Sirenian (sea cows)
- Ursids (polar bears)
- Mustelids (sea otters)
What does ‘galumph’ mean? (just a fun question)
To move around like a sea lion
How do you distinguish between a California versus Steller’s sealions based on colour, body shape, body size, vocalization?
California Sea Lion
- Darker
- Slender
- Smaller
- Bark
Stellar Sea Lion
- Lighter
- Chunkier
- Larger
- Roar
Who is the largest pinniped and what family do they belong to? Where do you see them typically?
Elephant seals – Phocidae.
Mexico??
What cues would you use to locate cetaceans (he mentioned at least five cues)?
- can identify species from size/shape of blow
- can identify by fluke shape, skin colour/texture, pectoral fin size, behavior, location
- can identify by auditory/olfactory cues
- can identify by other species (marine birds) indicate whales are present
What are some of the distinguishing characteristics of Odontocetes (same as question 4 of the notes)?
- Teeth
- One blowhole
- No ventral pleats
- Echolocation
- More social
- Non-migratory
Contrast the distinguishing characteristics of dolphins and porpoises (same as question 11 of the notes).
Dolphin
- 1.5 to 10 m long
- Forehead bulges, distinct beak, long rostrum
- Teeth cone shaped (unlobed)
- Curved dorsal fins
Porpoise
- 1.2 to 2.2 m (smaller)
- Blunt snout, no beak, short rostrum
- Teeth spade shaped (2-3 lobes)
- Fin is triangular (not curved)
How would you distinguish a harbour porpoise from a Dall’s porpoise (size, group size, colour patterns, which one associates with boats, where do they generally hang out (i.e., likelihood of seeing them)?
Harbour Porpoise
- 1.75 m
- 1-5 per group
- Shallow coastal waters
- Elusive
- special concern
- Counter shading
Dall’s Porpoise
- 2m
- 4-20 per group
- Coastal/oceanic
- Fast moving
- Not at risk
- White patch on sides & on dorsal fin
Characteristics of resident killer whales
Residents
- Fish eating
- SRKW: 73
- NRKW: 230 ish ?
- Do not interbreed
- Dorsal fin rounded with pointed trailing tip
- Very open saddle
- Males – tall dorsal (maybe slanted forward)
Characteristics of transient killer whales
Transient
- Mammal eaters
- Single male goes off and hunts and returns to mama
- Pointed dorsal
- Saddle extends past midline of dorsal fin
Characteristics of off-shore killer whales
Offshore
- Around 300
- Prey on fish & sharks
- Threatened
- Teeth ware down over time.
- Faint saddle
- Fin rounded at tip
- Silent when hunting
What are the characteristics of sperm whales: size, skin characteristics, teeth, prey, blowhole
- M: 18 m, F:14 m
- 15 – 30 individuals
- Deep long dives (1 hour, 1000 m)
- No teeth on top jaw
- Wrinkled skin, scrapes/scratches
- Not at risk
- Blowhole: off to left, shoots forward
- Tiny little dorsal fin
What are some of the distinguishing characteristics of Mysticetes (same as question 4 of the notes)?
- Baleen (no teeth)
- Two blowholes
- Ventral pleats
- No echolocation
- Generally solitary
- Migratory (arctic - equator)
Who is the smallest of the baleen whales?
Minke
What is the very distinct aspect of the minke whale – identification wise
White band on pectoral fin
