1Whale Trust, Makawao, Hawaii 96768 United States of America
2BALYENA.ORG, Barangay Pangdan, 6308, Philippines and National Museum of the Philippines, Zoology Division, Manila, 1000 Philippines
3Deep Blue Conservancy, Puerto Vallarta, Jalisco, CP 48328 Mexico
4Universidad Autonoma de Baja California Sur, Departamento de Ciencias Marinas y Costeras, La Paz, Mexico
5Ogasawara Club, Komagari, Chichi-jima, Ogasawara, Tokyo, Japan
© The Author(s) 2019
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