DOCSLIB.ORG

What Is the Difference Between a Shark and a Dolphin?

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text

Load more

What is The Difference BetweenWhat a is the difference between a shark and a dolphin? Shark and a Dolphin? Blowhole to Horizontal tail fluke creates Dolphins are mammals and give birth breathe air. up and down propulsion to to live young. They nurse their calves swim. with milk that is very rich in fat. Sharks are fish. Most lay eggs and do not care for their young. Gills to extract oxygen from water. Mammary glands Flippers to produce milk for containing calves. bones similar to human hand bones. Vertical tail fin creates side Additional fins , Fin made of strong, to side propulsion to swim. second dorsal, flexible tissue pelvic and anal. called cartilage. What is The Difference BetweenWhat a is the difference between a whale and a dolphin? Shark and a Dolphin? Two blowholes Baleen Whale Baleen is the bristle like structure to breathe air. in a whale’s upper jaw which it uses to filter small fish or crustaceans from the water. Single blowhole to Many species we call whales breathe air. are more closely related to Throat pleats in some baleen dolphins. Generally scientists whales expand to fill with water Dolphin talk about baleen whales and small fish or crustaceans and and toothed then contract, pushing the water whales. Toothed whales back through the baleen. include sperm whales, beaked whales, and all Teeth on the upper and lower porpoises and dolphins. jaws to grab fish, squid or other Killer whales and pilot prey. They use echolocation to whales are actually dolphins. find their food. What is The Difference BetweenEcholocation a Shark and a Dolphin? Toothed whales (dolphins, porpoises and species like pilot Brain processes Nasal passage whales and killer whales) use echolocation to navigate and find signals to form an contains their food. They emit a series of soundwaves in the form of clicks image. organs that Melon (a fat filled and detect their reflections or echoes. produce clicks. organ) focuses outgoing soundwaves. Prey reflects soundwaves. Fat filled cavity in lower jaw receives reflected soundwaves. What is The Difference BetweenBaleen a Whale Filter Feeding Shark and a Dolphin? Baleen is the bristle like structure in a whale’s upper jaw which it uses to filter prey from the water. Small fish or crustaceans such Baleen whales feed on small as krill. fish and crustaceans such as krill. They take in prey with water, trapping their food on the inside of baleen plates, which are like bristles of a Throat pleats expand to fill with broom. Some species of baleen water and small fish or crustaceans whale don’t have throat pleats and then contract, pushing the 1 cm but still filter feed. water back through the baleen. What is The Difference BetweenMarine a Food Web Shark and a Dolphin? Top Predators Predators Filterers Detritivores (Feed on dead Herbivores organic matter) Producers Baleen Whale Anatomy Pelvic and leg bone Vertebrae (an evolutionary Lungs Liver Scapula (similar to remnant from human shoulder ancestors that had blade) legs) Intestine Anus Trachea Bladder Heart Reproductive tract Stomach Flipper Bones Kidney (similar to human hand bones) What is The Difference BetweenDolphin a Anatomy Shark and a Dolphin? Vertebrae Lungs Kidney Trachea Intestine Scapula (similar Bladder to human shoulder blade) Pelvic bone (an evolutionary remnant from ancestors that had legs) Anus Stomach Flipper Bones Heart Reproductive tract (similar to human hand bones) Liver Cetacean Habitats Many species have clear habitat preferences, determined by their feeding strategies. For example, sperm whales Bottlenose Dolphin Humpback Whale dive to great depths to Shore Killer Whale catch squid, while other Coastal species feed on fish and crustaceans in shallow, Species include: coastal waters. Other - Bottlenose Dolphin species target large - Humpback Dolphin schools of fish or - Atlantic Spotted Continental Shelf crustaceans on the Dolphin continental shelf. However, - Irrawaddy Dolphin Species include: some cetaceans, like - Humpback Whale Deep Sperm Whale bottlenose dolphins - Right Whale Water Some cetaceans also live in freshwater, - Minke Whale Including: and killer whales, can be such as Amazon river dolphins, Ganges - Common Dolphin - Risso’s found in almost any river dolphins and Irrawaddy dolphins. - Spinner Dolphin Dolphin marine environment. - Sperm Whale What is The Difference BetweenSome a threats to whales and dolphins Shark and a Dolphin? CLIMATE CHANGE causes the oceans to warm which can result in shifts and changes in food resources for whales and dolphins. SHIP STRIKES kill or injure large whales and sometimes smaller whales or dolphins. ENTANGLEMENT UNDER in fishing gear leads to immediate WATER death from asphyxiation or long- term injuries and inability to feed NOISE or reproduce. can damage hearing, mask POLLUTION communication and harmful and contaminants build up in echolocation, the food chain reaching and cause stress, high levels in top driving predators like dolphins cetaceans away and killer whales. MARINE from feeding or DEBRIS resting habitats. such as plastic is often found in stomachs of stranded cetaceans..
Recommended publications
  • DOLPHIN RESEARCH CENTER Legends & Myths & More!

    DOLPHIN RESEARCH CENTER Legends & Myths & More!

    DOLPHIN RESEARCH CENTER Legends & Myths & More! Grade Level: 3rd -5 th Objectives: Students will construct their own meaning from a variety of legends and myths about dolphins and then create their own dolphin legend or myth. Florida Sunshine State Standards: Language Arts LA.A.2.2.5 The student reads and organizes information for a variety of purposes, including making a report, conducting interviews, taking a test, and performing an authentic task. LA.B.1.2 The student uses the writing processes effectively. Social Studies SS.A.1.2.1: The student understands how individuals, ideas, decisions, and events can influence history. SS.B.2.2.4: The student understands how factors such as population growth, human migration, improved methods of transportation and communication, and economic development affect the use and conservation of natural resources. Science SC.G.1.2.2 The student knows that living things compete in a climatic region with other living things and that structural adaptations make them fit for an environment. National Science Education Standards: Content Standard C (K-4) - Characteristics of Organisms : Each plant or animal has different structures that serve different functions in growth, survival, and reproduction. For example, humans have distinct body structures for walking, holding, seeing, and talking. Content Standard C (5-8) - Diversity and adaptations of Organisms : Biological evolution accounts for the diversity of species developed through gradual processes over many generations. Species acquire many of their unique characteristics through biological adaptation, which involves the selection of naturally occurring variations in populations. Biological adaptations include changes in structures, behaviors, or physiology that enhance survival and reproductive success in a particular environment.
  • Toothed Vs. Baleen Whales Monday

    Toothed Vs. Baleen Whales Monday

    SPOT THE DIFFERENCE: TOOTHED VS. BALEEN WHALES MONDAY Their classifications help to give you the answer, so what do you think the most obvious difference is in a toothed whale versus a baleen whale? Your clues are in the close-up photos, below! PHOTO: TASLI SHAW PHOTO: CINDY HANSEN Answer: The most obvious difference between a toothed whale and a baleen whale is the way that they feed and what’s inside their mouth. Toothed whales (including all dolphins and porpoises) have teeth, like we do, and they actively hunt fish, squid, and other sea creatures. Their teeth help them capture, bite, and tear their food into smaller pieces before swallowing. Baleen whales have several hundred plates that hang from their upper jaw, instead of teeth. These plates are made of keratin, the same substance as our hair and fingernails, and are used to filter food from the water or the sediment. Once the food has been trapped in the baleen plates, the whales will use their massive tongues to scrape the food off and swallow it. SPOT THE DIFFERENCE: TOOTHED VS. BALEEN WHALES TUESDAY The photos provided show specific prey types for resident orcas and for the gray whales that stop to feed in Saratoga Passage in the spring. Besides being two different species, what is another difference between these prey types? Who eats what and what makes you think that? Answer: The photos show Chinook salmon and ghost shrimp. Other than being two different species, their main difference is size! A toothed whale, like a resident orca, uses their teeth to capture, bite, and tear Chinook salmon into smaller pieces to be shared with other orcas in their family.
  • Morphology and Distribution of the Spinner Dolphin, Stenella

    Morphology and Distribution of the Spinner Dolphin, Stenella

    J. CETACEAN RES. MANAGE. 1(2):167- 177 , 1999 167 Morphology and distribution of the spinner dolphin,Stenella longirostris, rough-toothed dolphin,Steno bredanensis and melon-headed whale,Peponocephala electra, from waters off the Sultanate of Oman1 Koen Van W aerebeek*, M ichael G allagheri Robert Baldwin Vassili Papastavrou§ and Samira M ustafa A l - L a w a t i 1 Contact e-mail: [email protected] ABSTRACT The morphology of three tropical delphinids from the Sultanate of Oman and their occurrence in the Arabian Sea are presented. Body lengths of four physically mature spinner dolphins (three males) ranged from 154-178.3cm (median 164.5cm), i.e. smaller than any known stock of spinner dolphins, except the dwarf forms from Thailand and Australia. Skulls of Oman spinner dolphins (n = 10) were practically indistinguishable from those of eastern spinner dolphins ( Stenella longirostris orientalis) from the eastern tropical Pacific, but were considerably smaller than skulls of populations of pantropical ( Stenella longirostris longirostris) and Central American spinner dolphins (Stenella longirostris centroamericana). Two colour morphs (CM) were observed. The most common (CM1) has the typical tripartite pattem of the pantropical spinner dolphin. A small morph (CM2), so far seen mostly off Muscat, is characterised by a dark dorsal overlay obscuring most of the tripartite pattern and by a pinkish or white ventral field and supragenital patch. Two skulls were linked to a CM1 colour morph, the others were undetermined. It is concluded that Oman spinner dolphins should be treated as a discrete population, morphologically distinct from all known spinner dolphin subspecies.
  • Marine Mammals of Hudson Strait the Following Marine Mammals Are Common to Hudson Strait, However, Other Species May Also Be Seen

    Marine Mammals of Hudson Strait the Following Marine Mammals Are Common to Hudson Strait, However, Other Species May Also Be Seen

    Marine Mammals of Hudson Strait The following marine mammals are common to Hudson Strait, however, other species may also be seen. It’s possible for marine mammals to venture outside of their common habitats and may be seen elsewhere. Bowhead Whale Length: 13-19 m Appearance: Stocky, with large head. Blue-black body with white markings on the chin, belly and just forward of the tail. No dorsal fin or ridge. Two blow holes, no teeth, has baleen. Behaviour: Blow is V-shaped and bushy, reaching 6 m in height. Often alone but sometimes in groups of 2-10. Habitat: Leads and cracks in pack ice during winter and in open water during summer. Status: Special concern Beluga Whale Length: 4-5 m Appearance: Adults are almost entirely white with a tough dorsal ridge and no dorsal fin. Young are grey. Behaviour: Blow is low and hardly visible. Not much of the body is visible out of the water. Found in small groups, but sometimes hundreds to thousands during annual migrations. Habitat: Found in open water year-round. Prefer shallow coastal water during summer and water near pack ice in winter. Killer Whale Status: Endangered Length: 8-9 m Appearance: Black body with white throat, belly and underside and white spot behind eye. Triangular dorsal fin in the middle of the back. Male dorsal fin can be up to 2 m in high. Behaviour: Blow is tall and column shaped; approximately 4 m in height. Narwhal Typically form groups of 2-25. Length: 4-5 m Habitat: Coastal water and open seas, often in water less than 200 m depth.
  • Cognitive Adaptations of Social Bonding in Birds Nathan J

    Cognitive Adaptations of Social Bonding in Birds Nathan J

    Phil. Trans. R. Soc. B (2007) 362, 489–505 doi:10.1098/rstb.2006.1991 Published online 24 January 2007 Cognitive adaptations of social bonding in birds Nathan J. Emery1,*, Amanda M. Seed2, Auguste M. P. von Bayern1 and Nicola S. Clayton2 1Sub-department of Animal Behaviour, University of Cambridge, Cambridge CB3 8AA, UK 2Department of Experimental Psychology, University of Cambridge, Cambridge CB2 3EB, UK The ‘social intelligence hypothesis’ was originally conceived to explain how primates may have evolved their superior intellect and large brains when compared with other animals. Although some birds such as corvids may be intellectually comparable to apes, the same relationship between sociality and brain size seen in primates has not been found for birds, possibly suggesting a role for other non-social factors. But bird sociality is different from primate sociality. Most monkeys and apes form stable groups, whereas most birds are monogamous, and only form large flocks outside of the breeding season. Some birds form lifelong pair bonds and these species tend to have the largest brains relative to body size. Some of these species are known for their intellectual abilities (e.g. corvids and parrots), while others are not (e.g. geese and albatrosses). Although socio-ecological factors may explain some of the differences in brain size and intelligence between corvids/parrots and geese/albatrosses, we predict that the type and quality of the bonded relationship is also critical. Indeed, we present empirical evidence that rook and jackdaw partnerships resemble primate and dolphin alliances. Although social interactions within a pair may seem simple on the surface, we argue that cognition may play an important role in the maintenance of long-term relationships, something we name as ‘relationship intelligence’.
  • Southern Resident Killer Whales (Orcinus Orca) Cover: Aerial Photograph of a Mother and New Calf in SRKW J-Pod, Taken in September 2020

    Southern Resident Killer Whales (Orcinus Orca) Cover: Aerial Photograph of a Mother and New Calf in SRKW J-Pod, Taken in September 2020

    SPECIES in the SPOTLIGHT Priority Actions 2021–2025 Southern Resident killer whales (Orcinus orca) Cover: Aerial photograph of a mother and new calf in SRKW J-pod, taken in September 2020. The photo was obtained using a non-invasive octocopter drone at >100 ft. Photo: Holly Fearnbach (SR3, SeaLife Response, Rehab and Research) and Dr. John Durban (SEA, Southall Environmental Associates); collected under NMFS research permit #19091. Species in the Spotlight: Southern Resident Killer Whales | PRIORITY ACTIONS: 2021–2025 Central California Coast coho salmon adult, Lagunitas Creek. Photo: Mt. Tamalpais Photos. Passengers aboard a Washington State Ferry view Southern Resident killer whales in Puget Sound, an example of low-impact whale watching. Photo: NWFSC. The Species in the Spotlight Initiative In 2015, the National Marine Fisheries Service (NOAA Fisheries) launched the Species in the Spotlight initiative to provide immediate, targeted efforts to halt declines and stabilize populations, focus resources within and outside of NOAA on the most at-risk species, guide agency actions where we have discretion to make investments, increase public awareness and support for these species, and expand partnerships. We have renewed the initiative for 2021–2025. U.S. Department of Commerce | National Oceanic and Atmospheric Administration | National Marine Fisheries Service 1 Species in the Spotlight: Southern Resident Killer Whales | PRIORITY ACTIONS: 2021–2025 The criteria for Species in the Spotlight are that they partnerships, and prioritizing funding—providing or are endangered, their populations are declining, and leveraging more than $113 million toward projects that they are considered a recovery priority #1C (84 FR will help stabilize these highly at-risk species.
  • Commonly Found Marine Mammals of Puget Sound

    Commonly Found Marine Mammals of Puget Sound

    Marine Mammals of Puget Sound Pinnipeds: Seals & Sea Lions Cetaceans: Pacific Harbor Seal Whales, Dolphins & Porpoise Phoca vitulina Adults mottled tan or blue-gray with dark spots Seal Pups Orca Male: 6'/300 lbs; Female: 5'/200 pounds Earless (internal ears, with externally visible hole) (or Killer Whale) Short fur-covered flippers, nails at end Drags rear flippers behind body Orcinus orca Vocalization: "maah" (pups only) Black body with white chin, Most common marine mammal in Puget Sound belly, and eyepatch Shy, but curious. Pupping occurs June/July in Average 23 - 26'/4 - 8 tons the Strait of Juan de Fuca and San Juan Islands Southern Resident orcas (salmon-eating) are Endangered, travel in larger pods Northern Elephant Seal If you see a seal pup Transient (marine mammal -eating) orcas alone on the beach travel in smaller pods Orcas are most often observed in inland waters Mirounga angustirostris DO NOT DISTURB - fall - spring; off San Juan Islands in summer Brownish-gray it’s the law! Dall's Porpoise Male: 10-12'/4,000-5,000 lbs Human encroachment can stress the pup Female: 8-9'/900-1,000 lbs. Phocoenoides dalli and scare the mother away. Internal ears (slight hole) For your safety and the health of the pup, Harbor Porpoise Black body/white belly and sides Short fur-covered flippers, nails at end leave the pup alone. Do not touch! White on dorsal fin trailing edge Drags rear flippers behind body Phocoena phocoena Average 6 - 7'/300 lbs. Vocalization: Guttural growl or belch Dark gray or black Travels alone or in groups of 2 - 20 or more Elephant seals are increasing in with lighter sides and belly Creates “rooster tail” spray, number in this region Average 5- 6'/120 lbs.
  • Cetacean Records Along a Coastal-Offshore Gradient in the Vitória

    Cetacean Records Along a Coastal-Offshore Gradient in the Vitória

    DOI: http://dx.doi.org/10.1590/1519-6984.21812 Cetacean records along a coastal-offshore gradient in the Vitória- Trindade Chain, western South Atlantic Ocean Wedekin, LL.a*, Rossi-Santos, MR.a, Baracho, C.a, Cypriano-Souza, AL.a,b and Simões-Lopes, PC.c aInstituto Baleia Jubarte, Rua Barão do Rio Branco, 125, CEP 45900-000, Caravelas, BA, Brazil bLaboratório de Biologia Genômica e Molecular, Faculdade de Biociências, Pontifícia Universidade Católica do Rio Grande do Sul – PUCRS, Avenida Ipiranga, 6681, CEP 90619-900, Porto Alegre, RS, Brazil cLaboratório de Mamíferos Aquáticos – LAMAQ, Departamento de Ecologia e Zoologia, Universidade Federal de Santa Catarina – UFSC, Campus Universitário, CP 5102, Trindade, CEP 88040-970, Florianópolis, SC, Brazil *e-mail: [email protected] Received: November 2, 2012 – Accepted: December 27, 2012 – Distributed: February 28, 2014 (With 2 figures) Abstract Oceanic waters are difficult to assess, and there are many gaps in knowledge regarding cetacean occurrence. To fill some of these gaps, this article provides important cetacean records obtained in the winter of 2010 during a dedicated expedition to collect visual and acoustic information in the Vitória-Trindade seamounts. We observed 19 groups of cetaceans along a 1300-km search trajectory, with six species being identified: the humpback whale Megaptera( novaeangliae, N = 9 groups), the fin whale (Balaenoptera physalus, N = 1), the Antarctic minke whale (Balaenoptera bonaerensis, N = 1), the rough-toothed dolphin (Steno bredanensis, N = 1), the bottlenose dolphin (Tursiops truncatus, N = 2), and the killer whale (Orcinus orca, N = 1). Most humpback whale groups (N = 7; 78%) were observed in the Vitória-Trindade seamounts, especially the mounts close to the Abrolhos Bank.
  • (Ziphius Cavirostris) at Isla Guadalupe, Mexico Therya, Vol

    (Ziphius Cavirostris) at Isla Guadalupe, Mexico Therya, Vol

    Therya E-ISSN: 2007-3364 [email protected] Asociación Mexicana de Mastozoología México Gallo-Reynoso, Juan Pablo; Hoyos-Padilla, Edgar Mauricio First stranding record of a Cuvier beaked whale (Ziphius cavirostris) at Isla Guadalupe, Mexico Therya, vol. 6, núm. 2, mayo, 2015, pp. 329-336 Asociación Mexicana de Mastozoología Baja California Sur, México Available in: http://www.redalyc.org/articulo.oa?id=402339248005 How to cite Complete issue Scientific Information System More information about this article Network of Scientific Journals from Latin America, the Caribbean, Spain and Portugal Journal's homepage in redalyc.org Non-profit academic project, developed under the open access initiative THERYA, 2015, Vol. 6 (2): 329-336 DOI: 10.12933/therya-15-272, ISSN 2007-3364 Primer registro de varamiento del Zifio de Cuvier (Ziphius cavirostris) en Isla Guadalupe, México First stranding record of a Cuvier beaked whale (Ziphius cavirostris) at Isla Guadalupe, Mexico Juan Pablo Gallo-Reynoso1* and Edgar Mauricio Hoyos-Padilla2 1Centro de Investigación en Alimentación y Desarrollo, A. C. Unidad Guaymas, Carretera al Varadero Nacional, km 6.6, Las Playitas, Guaymas, 85480, Sonora, México. E-mail: [email protected] (JPGR). 2Pelagios-Kakunjá A.C. Sinaloa 1540, 23070, La Paz, Baja California Sur, México. E-mail: [email protected] (EMHP). *Corresponding author. Introduction: A calf of a Cuvier beaked whale, Ziphius cavirostris, was found stranded at Isla Guadalupe, Mexico where this species have been observed before. Methods: A detailed necropsy was conducted to report the plausible stranding causes. The individual was measured. Results: The female calf was apparently a month old individual and was still suckling.
  • Download Independent Chucks Brochure

    Download Independent Chucks Brochure

    PRODUCT CATALOG www.buckchuck.com Table of Contents Technical Information Why a Buck? .................................................................................................................................................................................................................................................3 Manual Chuck Selection ......................................................................................................................................................................................................................5 Spindle Identification for Mounting Plates .................................................................................................................................................................................6 Obsolete Chuck Crossover ...............................................................................................................................................................................................................7 Parts Breakdown ......................................................................................................................................................................................................................................8 ATSC Manual Steel Body Scroll Chucks --- Ajust-Tru ® Style 3 and 6 Jaw - Forged Steel Body Scroll Chuck - Hardened Reversible Top Jaws .................................................................................................9 3 and 6 Jaw - Forged Steel Body Scroll Chuck - Hardened
  • Intelligence in Corvids and Apes: a Case of Convergent Evolution? Amanda Seed*, Nathan Emery & Nicola Claytonà

    Intelligence in Corvids and Apes: a Case of Convergent Evolution? Amanda Seed*, Nathan Emery & Nicola Claytonà

    Ethology CURRENT ISSUES – PERSPECTIVES AND REVIEWS Intelligence in Corvids and Apes: A Case of Convergent Evolution? Amanda Seed*, Nathan Emery & Nicola Claytonà * Department of Psychology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany School of Biological & Chemical Sciences, Queen Mary University of London, London, UK à Department of Experimental Psychology, University of Cambridge, Cambridge, UK (Invited Review) Correspondence Abstract Nicola Clayton, Department of Experimental Psychology, University of Cambridge, Downing Intelligence is suggested to have evolved in primates in response to com- Street, Cambridge CB23EB, UK. plexities in the environment faced by their ancestors. Corvids, a large- E-mail: [email protected] brained group of birds, have been suggested to have undergone a con- vergent evolution of intelligence [Emery & Clayton (2004) Science, Vol. Received: November 13, 2008 306, pp. 1903–1907]. Here we review evidence for the proposal from Initial acceptance: December 26, 2008 both ultimate and proximate perspectives. While we show that many of Final acceptance: February 15, 2009 (M. Taborsky) the proposed hypotheses for the evolutionary origin of great ape intelli- gence also apply to corvids, further study is needed to reveal the selec- doi: 10.1111/j.1439-0310.2009.01644.x tive pressures that resulted in the evolution of intelligent behaviour in both corvids and apes. For comparative proximate analyses we empha- size the need to be explicit about the level of analysis to reveal the type of convergence that has taken place. Although there is evidence that corvids and apes solve social and physical problems with similar speed and flexibility, there is a great deal more to be learned about the repre- sentations and algorithms underpinning these computations in both groups.
  • Balaenoptera Bonaerensis – Antarctic Minke Whale

    Balaenoptera Bonaerensis – Antarctic Minke Whale

    Balaenoptera bonaerensis – Antarctic Minke Whale compared to B. bonaerensis. This smaller form, termed the “Dwarf” Minke Whale, may be genetically different from B. bonaerensis, and more closely related to the North Pacific Minke Whales, and thus has been classified B. acutorostrata (Wada et al. 1991; IWC 2001). This taxonomic position, although somewhat controversial, has been accepted by the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), and the Convention on Migratory Species (CMS). Assessment Rationale The current IWC global estimate of abundance of Antarctic Dr. Meike Scheidat Minke Whales is about 500,000 individuals. The abundance estimates declined from about 700,000 for the second circumpolar set of abundance survey cruises Regional Red List status (2016) Least Concern* (1985/86 to 1990/91) to about 500,000 for the third National Red List status (2004) Least Concern (1991/92 to 2003/04). Although this decline was not statistically significant, the IWC Scientific Committee does Reasons for change No change consider these results to reflect a change. However, Global Red List status (2008) Data Deficient whether this change is genuine or attributed to greater proportions of pack ice limiting the survey extent, has not TOPS listing (NEMBA) (2007) None yet been determined. More detailed results from an CITES listing (1986) Appendix I assessment model are available for the mid-Indian to the mid-Pacific region, and suggest that the population Endemic No increased to a peak in 1970 and then declined, with it *Watch-list Data being unclear whether this decline has levelled off or is still continuing past 2000.