An Introduction to Marine Mammals: with a Focus on India
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An Introduction to Marine Mammals: With a focus on India Mridula Srinivasan, Ph.D. Terra Marine Research Institute 2/14/2014 2013 Timi-Kurm Festival 1 Roadmap Marine Mammal Basics Why Marine Mammals are Unique Marine Mammal Types Cetaceans Cetaceans of India Studying Marine Mammals 2/14/2014 2 Mammals BASICS Nurse young Have hair Warm blooded Four-chambered heart Parental Care Lungs to breathe Same core body temperature 2/14/2014 3 Marine Mammal BASICS Nurse young Have hair Warm blooded Four-chambered heart Parental Care Lungs to breathe Same core body temperature 2/14/2014 4 Marine Mammal Basics Cont.… Gestation period range: 10-17.5 months 1 – 3 year birth interval breeding – migration (only whales) – feeding – calving – lactation – weaning – resting/playing 2/14/2014 5 Hippopotamus - Whales & Dolphins Bears - Seals Manatees & Dugongs - ELEPHANTS 2/14/2014 6 Whale Evolution VIDEO 2/14/2014 7 What makes marine mammals unique ? Breath holding (High Myoglobin) Live and reproduce for the most part in water Deep divers May drink salt water, get water from prey Longest migrations Blubber/fur (insulation) 2/14/2014 8 • Above and below water • No eyelashes • More rods then cones/some color vision http://2/14/2014cetus.ucsd.edu/voicesinthesea_org/videos/videos.html (VOICES OF THE SEA) 9 ~78 SPECIES OF WHALES, DOLPHINS, PORPOISES 2/14/2014 10 4 species (manatees and dugong) 2/14/2014 11 ~33 species of seals, sea lions, walrus 2/14/2014 12 Sea Otters Polar Bears Marine - related to weasels, Depend on ocean for food badgers,2/14/2014 river otters 13 Marine Mammals of the World – Classification Kingdom Animalia Phylum Chordata Class Mammalia Order – Cetacea – Whales and Dolphins Order – Sirenia – Manatees and Dugongs Order – Carnivora – Polar bear, seals, sea lions, otters 2/14/2014 14 Taxonomy – Family Whales, Dolphins, and Porpoises (Cetaceans) Seals, Sea Lions, and Balaenidae Walrus (Pinnipeds) Neobalaenidae Phocidae Eschrichtiidae Otariidae Balaenopteridae Odobenidae Physeteridae Kogiidae Manatees and Dugongs Platanistidae (Sirenia) Pontoporiidae Trichechidae Lipotidae Dugongidae Iniidae Polar Bears and Sea Monodontidae Otters (Carnivores) Phocoenidae Ursidae Delphinidae Mustelidae Ziphiidae2/14/2014 15 Cetaceans: Whales and Dolphins, and Porpoises Two Sub-Orders--- Odontocetes (Toothed Whales) Mysticetes (Baleen Whales) 2/14/2014 16 Marine Mammals of India • KNOWN 20-25 species found in India - Ganges River Dolphins - Indo-Pacific Humpback Dolphins - Irrawaddy Dolphins - Dwarf Sperm Whales - Bottlenose dolphins - Dugongs - Beaked whales - Finless Porpoise - Humpback Whales - Sperm Whales 2/14/2014 17 Baleen whales or Mysticetes Have 2 blow holes Females are larger than males Mostly solitary, but cooperate during feeding! Long migrations Use low frequency sounds (<10KHz)to communicate long distances 4 families with a total 2/14/2014 of 14 species 18 2/14/2014 19 Mysticete External Morphology 2/14/2014 20 Tooth brush or baleen!! 2/14/2014 21 Baleen size and feeding technique Gray whale – shortest baleen sediment or bottom feeding. Biggest reason for organic sediment turnover in the oceans. Right and bowhead whales – thickest and longest baleen – skim feeders Humpback and blue whales ( rorqual whales) – intermediate length baleen mid-water column feeding, gulp or lunge feeders 2/14/2014 22 2/14/2014 23 Know a whale from its blow! Right Whale Blow Characteristic V- shaped 2/14/2014 24 Family: Balaenopteridae Blue whale (Balaenoptera musculus • Rorquals (2 genera, 8 • 30-100 gular grooves species) • Short baleen plates, 200+ • 7 separated cervical per side vertebrae • Small dorsal fin behind 2/14/2014midline 25 Toothed Whales or Odontocetes One blowhole Killer whales sexually dimorphic Strong social bonds Known for their human/chimp equivalent Cognition and Intelligence Use echolocation to feed and communicate Use high frequency sounds to communicate 10kHz- 100KHz 10 families with at least 71 2/14/2014 species 26 Odontocete External Morphology 2/14/2014 27 Female (Lagenorhynchus obscurus) 2/14/2014 28 Male (Lagenorhynchus obscurus) 2/14/2014 29 Family: Physeteridae Produces ambergris – a valuable substance in perfumes. • Sperm whale (Physeter • All cervical vertebrae except macrocephalus): 1 species first are fused • Males 15-18 m; females up to • 18-25 conical teeth on lower jaw only 11 m • Dorsal hump; no fin • Feeds primarily on deep-water 2/14/2014 squid at depths of up to 600m30 Family: Kogiidae • Pygmy and dwarf sperm whales (1 genus, 2 species) • Blunt, shark-like head Pygmy sperm whale (Kogia breviceps) • Small, sub-terminal lower jaw • 24-32 conical teeth in lower jaw • Diet primarily deep-sea cephalopods and slow moving fish Breaching2/14/2014 Dwarf sperm whale (Kogia simus) 31 Family: Ziphiidae A rare photograph of Blainville’s beaked whale (Mesoplodon densirostris) Northern Bottlenose whale (Hyperoodon ampullatus) aboard a whaling ship • Beaked whales (6 genera, 20 • 1-2 pairs of teeth on lower known species) jaw in most species • Protruding rostrum with • Non-notched flukes arched jaws • Feeds primarily on deep- • Small dorsal fin past midline sea squid • Cuvier’s beaked whale – • Also has spermaceti Deepest diving record – 1,800 2/14/2014meters in 45 minutes 32 Family: Platanistidae Platanista gangetica India’s National Aquatic Animal Two captive Susus (Platanista sp.) • Indus (bhulan) & Ganges (susu)• Broad, paddle-like pectoral fins river dolphins (1 species) • 2-3 m in length • Long, narrow beak with no whiskers • Range limited to the Indus and Ganges river basins. • No dorsal fin; low dorsal hump • Small2/14/2014 eyes and poor vision 33 Family: Delphinidae • 36 species, 17 genera • Range from 1.5-10 m in length, 50-9000 kg • Conical, functional teeth in both jaws • All but genus Lissodelphis have Common dolphin dorsal fin (Delphinus delphis) 2/14/2014 34 Family: Phocoenidae • The porpoises: 3 genera with 6 species • Porpoises are distinguished from other Odontocetes by their small body size Finless porpoise (Neophocaena phocaenoides) • The porpoises are an elusive and relatively poorly known group. They feed on small pelagic and mesopelagic fish and squid. Their lifespans are relatively short (~20 years), and they usually spend their time in small, fluid social 2/14/2014 groups. 35 Harbor porpoise (Phocoena phocoena) Dolphin and Porpoise features Porpoise Features Dolphin Features spade shaped teeth cone shaped teeth triangular dorsal fin curved or hooked dorsal fin 2/14/2014 36 no beak often prominent beak What can we hope to see in waters near Karwar and Goa 2/14/2014 37 2/14/2014 38 What can we learn from studying dolphins and whales and how do we study them? 2/14/2014 39 Photo Identification • Identifying unique individuals by markings on their dorsal fin • Saddle-patches plus dorsal fin for killer whales 2/14/2014 40 Dorsal Fins Top Trailing edge chopped Unusual pigmentation/ Leading Edge Top Notch scars 2/14/2014 41 What can we use this for? • Movement patterns (migrations) • Habitat use and Distributions • Site fidelity • Population estimates and Abundance • Association patterns (social behavior) • Predation & Predator Effects • Behavior – Feeding, Mating, Social, Play • Behavioral Ecology • Environmental and Human Effects • Wildlife Management and Policy • Environmental Regulations LOCAL,2/14/2014 REGIONAL, NATIONAL, GLOBAL SCALES 42 Other Techniques • Biopsy • Radio Tracking and Satellite Tagging • Boat-based studies • Theodolite tracking (Hill-based) • Unmanned systems • Acoustic tracking – listening to whales • Aerial and Ship surveys • Modeling 2/14/2014 43 WHY SHOULD WE CARE? They are like “humans” Top of the food chain ‘TIGERS OF THE SEA’ Sentinels of Ocean Health and Climate Change They keep ecosystems in check National Aquatic Animal – Ganges River Dolphin 2/14/2014 44 The End Thank you! 2/14/2014 45 Back Up Slides 2/14/2014 46 WHOI CSI • http://csi.whoi.edu/interactive/harborporpois e2d (harbor porpoise body) • http://csi.whoi.edu/interactive/pinnipedskulld orsal2d (pinniped skull) • http://csi.whoi.edu/interactive/odontocetesku lllateral2d (dolphin skull lateral) 2/14/2014 47 .