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Home , Marine otter

Bio 358 1st Edition Exam # 1 Study Guide Lectures: 1 - 8

Lecture 1 (January 13)

Definition of a Marine : a functional descriptor of a diverse assemblage of distantly related that spend some or all of their life in a marine (or aquatic) environment

Marine mammals are not an evolutionary valid grouping, they are not monophyletic as a whole and they are a FUNCTIONAL GROUPING

4 anatomical adaptations marine mammals have in common:  Body streamlining = minimum protuberances, fusiform body shape, genitalia internal  Reduced or modified appendages = pectorals (flippers), pelvic (reduced or absent in fully aquatic orders)  Insulation = or blubber  LARGE body size

3 physiological adaptations marine mammals have in common:  Enhanced breath holding capabilities – apnea  Specialized thermoregulatory capabilities and vascular structures –water sucks heat away 25x faster than air  Specialized sensory systems – light is attenuated in water

Humans have direct and indirect effects on marine mammals:  Direct = hunting/exploitation for oil, fur, meat  Indirect = global climate change, fishing, SONAR (louddd), toxins, habitat destruction, vessel strikes…

Lecture 2 (January 15)

Scientific Names to Know:

Eumetopias jubatus Stellar’s

Callorhinus ursinus Northern

Cystophora cristata

Leptonychotes weddelli Weddel seal

Mirounga leonine Southern Odobenus rosmarus

Enhydra lutris Sea

Ursus maritimus Polar

Dugong dugon Dugong

Trichechus manatus West Indian manatee

Hydrodamalis gigas Stellar’s sea cow

Eubalaena glacialis Northern right whale

Balaenoptera musculus Blue whale

Megaptera novaeangliae Humpback whale

Eschrichtius robustus Grey whale

Physeter macrocephalus Sperm whale

Tasmacetus shepherdi Shepherd’s beaked whale

Mesoplodon densirostris Blainsville’s beaked whale

Ziphius cavirostris Cuvier’s beaked whale

Tursiops truncatus Bottlenose dolphin

Grampus griseus Risso’s dolphin

Phocoena phocoena Harbor porpoise

Poceana sinus Vequita

Lipotes vexillifer Baji

Mirounga angustirostris Northern elephant seal

Monachus schauinslandi Hawaiian

Monachus tropicalis Caribbean monk seal of marine mammals to know:

Phylum = Chordota

Subphylum = Vertebrata

Class = Mammalia

3 Orders:

Order (5 families)

 Otariidae – sea lions and fur seals  Phocidae – true seals  Odebenidae –  Ursidae – polar bear  – marine and

Order Sirenia ( 2 families)

 Trichechidae - manatees  Dugongidae – dugong and stellars sea cow

Order Cetacea

Suborder Mysticeti

 Balaenidae – right whales  Balaeniopteridae – rorquals  Neobalaenidae – pygmy right whale  Eschrichtiidae – grey whale

Suborder Odontoceti:

 Physeteridae – sperm whale  Kogiidae – dwarf and pygmy sperm whales  Ziphiidae – beaked whales  Monodontidae – beluga, narwhal  Delphinidae – dolphins  Phocoenidae – porpoises  Platanistidae – Ganges and Indus river dolphins  Iniidae – Amazonian river dolphin (AKA boto)  Lipotidae – Yangtze river dolphin (AKA baiji)  Pontoporiidae –franciscana (AKA La Plata dolphin) – carnivora – “fin-footed” – fissipeds “split-footed”

All have: Large body size; Fur or blubber = insulation; Streamline body; Modified appendages = flippers; Enhanced diving; Enhanced thermoregulation; Enhanced sensory systems (for seeing/hearing/feeling in dark water); need hard substrate to breed = more vulnerable to human impact

Human effects: Direct = hunting for fur/oil and hunting as competitors in fisheries; indirect = competition for space, bicatch/injured in fisheries, pollution

As a whole they are a cosmopolitan group meaning you can find them all over; but no single species is cosmopolitan

3 Families: Otariidae, Phocidae, Odobenidae

Otariidae: 14 species; external pinnae; hind flippers CAN be brought under the body; wing like fore flippers for “flying” underwater; 4 teats; scrotal; live in marine habitats

Example species:

 Stellar’s Sea Lion (Eumetopias jubatus)- “broad forhead and mane”: largest otariids; sexually dimorphic; aggressive ; extremely exploited; threatened and endangered under MMPA in different part’s of its range; threatened by accidental and intentional fishery interactions and competition with humans for .  Galapagos Sea Lion: Walks on land using both fore and hind limbs; flying motion underwater with pec flippers for thrust; uses lift base thrust forces, entire stroke generates thrust.  California Sea Lion: only species with visible ears  (Callorhinus ursinus) –“beautifully furred bear”: discovered by Stellar and Pribiof in mid 1700’s; smaller than sea lions with pointed nose, unregulated hunting for 100 years = near extinction; 1911 North Pacific Fur Seal Convention = first international wildlife conservation movement = only subsistence hunting permitted.

Phocidae: 19 species, NO external pinnae; hind flippers CANNOT be brought under the body; foreflipper short and stubby = not for locomotion; locomotion with hind flippers; 2 teats; ascrotal; marine with a few freshwater;50-75 million individuals ~90% of all .

Example species:

 Ringed Seal: Smallest seal; Polar bear’s favorite dinner; Hide pups in “ice lairs” = little cave of ice.  Weddel Seal (Leptonychotes weddelli): Placid animal; Feeds on ;Great divers – 300 meters for 70 minutes; Not afraid of humans; remarkable divers – over 600 m; 70 minutes  Hooded seal (Cystophora cristata) “nose carries bladder”- shortest lactation of any mammal ~4 days; milk = 60% fat; pups gain ~15 lbs per day; bilobed nose pumped with blood = display for fighting and sex; secondary sex characteristic  Baikal Seal: Only live in 1 lake in Baikal Siberia; Exclusively freshwater.  : Live in the Antarctic; High endothermic vertebrate predator eat phocid pups and seals  -eater seal: Doesn’t eat ; most abundant pinniped; teeth form a sieve for catching krill; doing well - fell into a niche left open by human hunting of krill eating whales  Southern Elephant Seal (Mirounga leonine): Largest pinniped -5m long and up to 5,000 kg; Best diving record: 2 hours, 1500 meters  Northern Elephant Seal (Mirounga angustirostris): Second largest pinniped; deep diver; well studied; hunted to near extinction in 18,00’s (only 10-12 individuals); today over 110,000 individuals = success story.  Hawaiian Monk Seal (Monachus schauinslandi): Highly endangered ~1000 individuals; solitary ; endemic to Hawaii; low #’s =sensitive to disturbance; tame animals.  Carribean Monk Seal (Monachus tropicalis): discovered by Columbus in 1494;killed 100 per night for oil; Extinct in the 1950’s.

Odobenidae: 1 speceis; NO external ear pinnae; hind flippers CAN be brought under the body; foreflippers = shorter than otariids, used as stabilizers; swim mostly using hind flippers; 4 teats; ascrotal; marine

Example Species:

 Walrus (Odobenus rosmarus): Largest pinniped other than the elephant seal; Uses tusks to pull up on ice; only extant species in the genus and with tusks; exploited for oil, rough hide and ivory (tusks); threatened by global climate change.

Lecture 3 ( January 20)

 Family Mustelidae: includes , , polecats and ; 2 marine species; exploited in 1740’s for fur .5 million sea otters killed in 150 years until 1911; 1911 = north pacific fur seal convention, protected fur seals AND otters sea otter #’s rose after this; susceptible to oil spills, fur must be clean.

Species:  Sea otter (Enhydra lutris): largest otter; never seen on land; lies on its back and holds air in its large lungs and fur which makes it VERY BUOYANT; can hold rocks and abalones on its chest and still float; use hind flippers to produce lift-based thrust forces for high speed swimming link hind limbs and dorsal ventrally oscillate  Marine Otter: more terrestrial than a sea otter; most recent ancestor = bear; “sea cat”; found off the coast and ; poached for fur coats; less than 1,000 individuals alive.

Family Ursidae: Polar bear = only marine ursid

Species:

 Polar bear ( maritimus): most recently evolved bear (~5.1-1 million years ago); closely related to brown ; more streamlined than other bears; use drag based thrust i.e. putting an oar in H20 thrust NOT generated during entire stroke = least efficient swimming style; not as well adapted for marine life; eats endotherms (mostly seals); threatened may 2008; Dr. Ian sterling noticed decreased body condition and reproductive outcome over time; DEPENDANT ON ICE  Global Climate Change = BAD NEWS; not highly adapted to swimming long distances. Order Sirenia: Most closely related to elephants, hyraxes; restricted to warm subtropical and tropical waters (15 C,60 F); almost exclusively herbivorous (sometimes eat things living on grass); non-ruminant herbivores (“hind-gut digesters”); may eat 55-90 kg/day; teeth replaced throughout life (horizontal replacement) teeth emerge and reach the front and then fall out… like a conveyor belt ; slow-moving, placid disposition

Families:

 Family Trichiridae  Family Dugongidae

Species:

 West Indian Manatee (Trichechus manatus): Teat in axilla (arm pit); many killed by boat strike; ID = boat strike scar patterns; become dependent on warm water outfalls of power plants = conservation issue; COLD SHOCK happens very easily - manatees found in NC from may to October, if they are found in September they are dead (from the cold); Have HUGE tail flukes.  Dugong (Dugong dugon): Endangered; Found in the indo-pacific; better swimmer, cetacean like fluke; more streamline; lift base thrust for entire locomotion cycle