Marine Mammalogy Introduction & Identification - Dalhousie University - Fall 2023 PDF

MARI 3090 – Marine Mammalogy Dalhousie University Dr. Amanda Babin Fall 2023 BMM 2012 Introduction & Identification What is a mammal? • Hair (most of the time) • Homeothermic • Nurse their young with milk animalfunnyfacts.blogspot.com • Air-breathing vertebrates What is a marine mammal? im...

MARI 3090 – Marine Mammalogy Dalhousie University Dr. Amanda Babin Fall 2023 BMM 2012 Introduction & Identification What is a mammal? • Hair (most of the time) • Homeothermic • Nurse their young with milk animalfunnyfacts.blogspot.com • Air-breathing vertebrates What is a marine mammal? imgcreative.net norwegianscitechnews.com • Not formal nomenclature • Informal aggregation of distantly related species • A mammal that inhabits the marine environment Blue whale The Marine Environment Heat Loss Weight Resistance Sound Light Air Water More Less More Far Less Surface Air Less More Less Near More = • Suborder: Mysticeti (Baleen whales) • Suborder: Odontoceti (Toothed whales) • Order: Carnivora • Clade: Pinnipedia (34+ species) • Family: Phocidae (True seals) • Family: Otariidae (Fur seals and Sea lions) • Family: Odobenidae (Walrus) elephantseal.org • Order: Cetartiodactyla • Infraorder: Cetacea (Whales, dolphins, and porpoises; 84+ species) elephantseal.org Taxonomic introduction • Order: Carnivora • Family: Mustelidae esa.org Taxonomic introduction footage.framepool • Sea otter, marine otter • Family: Ursidae • Polar bear • Order: Sirenia cetacea.de • Manatees and dugongs Cetaceans • Obligate aquatic environment • Horizontal fluke • Breathe through nostrils on top of head • Streamlined bodies (fusiform; convergent evolution with fish) • Mysticetes • Odontocetes • Baleen whales • 15 species • Toothed whales • 77 species ed101.bu Mysticete (baleen) vs. Odontocete (toothed) Mysticetes • Large body size • 2 blowholes • No melon • Symmetrical skull • Solid jaw bones • Elastic symphysis (flexible joint in chin to allow mouth to expand) Odontocetes • Variable body size • 1 blowhole • Melon • Asymmetrical skull • Hollow lower jaw bones • Symphyseal manible (joint fused for biting) • Baleen – keratin plates and bristles/fringes (sieve) • Feed on plankton and small fish • Large body size • Slight sexual dimorphism • More solitary museumvictoria.com.au Mysticetes • Variable number of teeth (zero – hundreds) • Feed on fish, squid, other marine mammals • Small to large body size • Sometimes strong sexual dimorphism • More social imagebacket.net Odontocetes Pinnipeds natgeomaps.com • Amphibious • Haul out on land/ice to birth and nurse Morphology • True seals • No external ear pinna • Hindlimbs cannot rotate forward • Generally spend more time at sea than otariids, dive deeper and longer • Northern phocids (10 species) • Southern phocids (6 species) • Monk seals (3 species) BMM 2012 Phocids Otariids • External ear pinna • Hindlimbs can rotate forward Fur seal Sea lion • Large forelimbs compared to phocids • Most species males have manes • Fur seal (9-10 species) • Smaller size, 2 layers of fur • Sea lions (5-6 species) • Larger size, 1 layer of fur coolantarctica.com eaglewingtours.com • Males 2-6x larger than females Odobenids • No external ear pinnae • Hindlimbs can rotate forward • Walrus (Odobenus rosmarus) Mustelids • Sea Otter (Engudra lutris) and marine otter (Lontra felina) Milo Burcham • Give birth, nurse, mate, molt, and forage in the water • Most dense fur of any animal – 150,000 hairs/square inch Ursid • Polar Bear (Ursus maritimus) animals.howstuffworks.com • Spends most of life on top of ice, gives birth on land • Preys on other marine mammals (seals) • Has blubber Sirenian • • • • • • Sea Cows Herbivorous Heavy bones Slow-moving Warm waters Thin blubber • Dugong (Dugong dugon) • Notched fluke • Marine • Manatees • Amazonian manatee (Trichechus inunguis) • West Indian manatee (Trichechus manatus) • West African manatee (Trichechus senegalensis) • Round fluke • Freshwater/Coastal Identification: Marine mammals of the Northwest Atlantic Minke whale newburyportwhalewatch Physical characteristics us.whales.org • Shape of blow (exhale) • Dorsal fin shape • Body length and shape • Head/rostrum shape • Colour pattern Orca teara.govt.nz The Blow Orca-Frederick-Sound-AK-07-24-05-234 Dorsal fin Broad-base Large falcate, mid-back Small falcate, posterior Triangular Tall Body length and shape Mike Nish commons.wikimedia.org • Mysticetes typically larger than odontocetes • Otariids typically larger than phocids Head/rostrum shape wdcs.org • Melon? • Beak? Harbour seal mysalishsea • Flat? Concave? Grey seal Harbour seal • Location of mustard colour pixdaus.com • Patterns whaleopedia Colour Atlantic white-sided dolphin Common dolphin • Shapes Jamie Watts • Chevron on fin whale • Eye patch, dorsal cape, and saddle on orca Other characteristics Minke whale ( Slice) Quoddy Link • Geographic location • Group size • Injuries (scars) • Age-related changes Beluga Reproduced with permission from Catherine Hood Blue Whale (Balaenoptera musculus) U-shaped head very large size blue-grey colour large size V-shaped head lower right lip and right baleen white dark colouration Reproduced with permission from Catherine Hood Fin whale (Balaenoptera physalus) greyish-white chevron distinctive ridge on head lower right lip is white Reproduced with permission from Catherine Hood Fin whale (Balaenoptera physalis) Humpback whale (Megaptera novaeangliae) dorsal fin sitting atop hump bushy blow flipper-waving group lunge feeding tubercles breaching lob-tailing Reproduced with permission from Catherine Hood timeturk.com Humpback behaviour narrow rostrum callosities Reproduced with permission from Catherine Hood bourlingueurs.com North Atlantic Right Whale (Eubalaena glacialis) arched cranium callosities long baleen Reproduced with permission from Catherine Hood North Atlantic Right Whale (Eubalaena glacialis) North Atlantic Right Whale (Eubalaena glacialis) V-shaped blow narrow, extremely pointed head white band on pectoral fins (Minke mittens) Reproduced with permission from Catherine Hood Minke Whale (Balaenoptera acutorostrata) Sperm Whale (Physeter macrocephalus) pxfuel.com large, square head low, bumpy dorsal fin wrinkled skin shobiklobik.com single blowhole on left distinct notch broad triangular flukes Reproduced with permission from Catherine Hood Sperm Whale (Physeter macrocephalus) rounded head & blunt beak white eye patch white chin Reproduced with permission from Catherine Hood pictures.blueplanetarchive.com Orca (Orcinus orca) large, erect dorsal fin (male) grey saddle patch Reproduced with permission from Catherine Hood Orca (Orcinus orca) white coloration (adult) small, bulbous head short beak, broad mouth-line robust body Reproduced with permission from Catherine Hood dfo-mpo.gc.ca Beluga (Delphinapterus leucas) black coloration rounded, bulbous head (pothead) merrinstitute.org Reproduced with permission from Catherine Hood marufkasim.blog.com Long-finned Pilot Whale (Globicephala melas) low, broad-based dorsal fin travels in groups us.whales.org Long-finned Pilot Whale (Globicephala melas) Common Dolphin (Delphinus delphis) leaps clear of the water large dorsal fin mustard patch anterior to dorsal fin hourglass pattern long pointed beak Atlantic White-Sided Dolphin (Lagenorhynchus acutus) mustard patch posterior tall falcate dorsal fin short beak white stripe below fin small, round beak-less head dark on top white belly Reproduced with permission from Catherine Hood Harbour Porpoise (Phocoena phocoena) Harbour Porpoise (Phocoena phocoena) triangular dorsal fin Erik Christensen dark on top “horsehead” shape darker pelage (male) lighter pelage (females) Reproduced with permission from Catherine Hood Grey Seal (Halichoerus grypus) Harbour Seal (Phoca vitulina) large eyes Reproduced with permission from Catherine Hood short muzzle V-shaped nostrils Grey seal vs. Harbour seal Harbour seal Quoddy Link July 25 2015 Grey seal Marine Mammal Identification Quiz racerock.com thetravelmagazine.net A. Babin Mingan Island Cetacean Study (MICS) Reproduced with permission from Catherine Hood Quoddy Link sciencefocus.com atvirukai.zebra.lt Quoddy Link Quoddy Link Answers 1. 2. 3. 4. 5. Harbour seal Humpback whale Orca Blue whale Fin whale 6. Minke whale 7. Sperm whale 8. Common dolphin 9. Harbour porpoise 10. Grey seal Take Home Messages • Marine mammals are not part of the same taxonomic group • Mysticetes have baleen, Odontocetes have teeth • Phocids do not have external ears and hind limbs do not rotate forward, Otariids have external ears and hind limbs rotate forward, Odobenids do not have external ears and hind limbs rotate forward • Identifying characteristics of species • V-shaped blow of the right whale, left-side blow of the sperm whale • Common dolphin mustard patch anterior to dorsal fin, Atlantic white-sided dolphin mustard patch posterior to dorsal fin Thank you!