BIO 358 1st Edition Lecture 2Outline of Last Lecture I. Who are marine mammals?II. Anatomical SpecializationsIII. Physiological Specializations IV. Human impactA. IndirectB. DirectV. Current Events Outline of Current Lecture I. Characteristics of PinnipedsII. Pinniped BreedingIII. Human impacts on pinnipedsIV. indirectV. direct VI. Pinniped DistributionVII. 3 families of pinnipedsA. Family Otariidaei. Characteristicsii. Example speciesB. Family Phocidaei. Characteristicsii. Example speciesC. Family Odobenidae i. Example specie D. Fun words about scrotums… Current LecturePinnipeds:- Order Carnivora – pinnipeds (“fin-footed” carnivores) - Most are carnivorous - All are fissipeds wich means “Split footed” Characteristics of all “pinnipeds”:- Large body sizeThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.- Fur or blubber = insulationo Fur is only on fur seals- Streamline body- Modified appendages = flippers- Enhanced diving- Enhanced thermoregulation - Enhanced sensory systems (for seeing/hearing/feeling in dark water)Breeding: - Need hard substrate- Access to land is required (either continental fringes or islands) - Need to be able to move both in and out of water which makes them unique in the marine mammal world. Human impacts on Pinnipeds: - Direct Impacts:o Hunting for food, fur and blubber (oil)o Hunted by fishermen because they are competitors for fish - Indirect Impacts: o Physical space... beach houses o Death and injury due to fishing lines/bycatch o Pollution – debris, toxins, oil spills... Distribution:- Cosmopolitan species = are distributed world wide o No single species is cosmopolitan, just the order as a whole Three Families of Pinnipeds: Family Otariidae (Otariids) – sea lions and fur seals Some Otariids:- exemplified by Steller’s sea lion and Southern sea lions- maintain polygynous mating system (one male, many females)- Extreme large body size in males enhances their ability to defend territories and females. - Galapagos Sea Lion:o Walks on lando Walk on both for and hind limbso Underwater movement = flying motion to glide through water using pectoral flippers for thrust o Use lift base thrust forces – entire stroke generates thrust - California Sea Lion:o External pinnae (ears) o They are the only species with visible ears- Steller’s sea lion (Eumetopias jubatus): o “broad forhead and mane” o heavily exploited o both endangered and threatened by the Marine Mammal Protection Act (MMPA) in multiple parts of its range. o Population may not reboundo Direct Threats = kill by fishermeno Indirect = dead in fisheries equipment, outcompeted by humans for fish o Largest otariid species  Males = 3 m long and 1000 kg Females = 2 m long and 270kg Sexual dimorphismo Highly aggressive - Fur Seals: Northern fur seal (Callorhinus ursinus)o “Beautifully furred bear” o smaller than sea lions with sharper noseso rely on fur for insulation: even wet fur can insulate barely any blubber very dense furo Discovered in mid 1700’s by Steller and Pribilof o Unregulated hunting for 100 years – 250,000 individuals killed Near extinction 1911 North Pacific Fur Seal Convention = first international wildlife conservation movement Family Phocidae (Phocids) – true seals - 50-75 million individuals - 90% of all pinnipeds- Graceful and wind like lift based thrust in water- Awkward on land - No external ear pinnae Some Phociids: - Ringed Seal:o Smallest sealo Polar bear’s favorite dinner o Hide pups in “ice lairs” = little cave of iceo Sucks that they taste so good… - Baikal seal:o Only live in one lake!!!!!o Lake in Baikal Siberiao Exclusively freshwater- Hooded seal (Cystophora cristata) o Shortest lactation period of any mammal ~4 dayso 60% fat milk (human milk is about 4-6% fat)o pups gain 15 lbs per dayo “nose carries a bladder” – male nose looks like a clown nose  bilobed nasa cavity allows male to evert his nasal septum and sac… blood is pumped into it so it is bright read… display for mating and fighting secondary sex characteristico live on unstable ice (fringes and floes) - Leopard Seal:o Live in the Antarctic o High endothermic vertebrate predator… they eat lots of things watch out yo! Phocid pups and seals = yumm- Weddell Seal:o Placid animalo Feeds on fishes o Great divers – 300 meters for 70 minuteso Not afraid of humans- Crab-eater Seal: o Doesn’t eat crabs… uh?o Most abundant pinniped o Teeth form a sieve for catching krillo They are doing well. They fell into a niche left open by humans when they hunted krill eating whales- Southern Elephant Seal (Mirounga leonine)o Largest pinniped = 5m long and up to 5,000 kgo Diving record: 2 hours 1500 meters- Northern Elephant Seal (Mirounga agustirostris) o Second largest pinniped o Deep diver – large body size = good deep diving o One of the best studied animalso Hunted to near extinction in the 18,00’s – there were only 10-12 individuals left!!!!!!!! Now there are over 110,000 individuals Yay!- Hawaiin Monk Seal (Monachus schauinslandi) o Highly endangered ~1000 individuals Due to tropical distributiono Solitary animalso Endemic to Hawaiio Sensitive to disturbances because of their low numberso They are pretty tame- Caribbean monk seals (Monachus tropicalis) o Discovered by Columbus in 1494o Killed 100 per night for oil WHILE THEY WERE SLEEPING… Jerkso Extinct in the 1950’s Family Odobenidae – walruses (odobenids) Some Odobenids (oh wait theres only one!):- Walrus (Odobenus rosmarus): o Largest pinniped other than the elephant sealo Uses tusks to pull up on ice o Only extant species in the genuso Only extant species with tuskso Exploited for oil, rough hide and ivory (tusks) Some New Terms: - Ascrotal = No scrotum, it never descends out of the body wall- Scrotal = Yes scrotum, these species tend to be