|Scientific Name:||Peponocephala electra|
|Species Authority:||(Gray, 1846)|
Electra electra (Gray, 1846)
Lagenorhynchus electra Gray, 1846
|Red List Category & Criteria:||Least Concern ver 3.1|
|Assessor(s):||Taylor, B.L., Baird, R., Barlow, J., Dawson, S.M., Ford, J., Mead, J.G., Notarbartolo di Sciara, G., Wade, P. & Pitman, R.L.|
|Reviewer(s):||Hammond, P.S. & Perrin, W.F. (Cetacean Red List Authority)|
Global trend or abundance data for this species are unavailable, however, abundance is at least 50,000. Threats that could cause widespread declines include high levels of anthropogenic sound, especially military sonar and seismic surveys, and localized competition with fisheries. The combination of the high global abundance and a large pan-tropical range with possible declines driven by more localized threats is believed sufficient to rule out a 30% global reduction over three generations (criterion A).
|Range Description:||Melon-headed whales have a pantropical distribution (Perryman 2002). The distribution coincides almost exactly with that of the pygmy killer whale in tropical/subtropical oceanic waters between about 40°N and 35°S (Jefferson and Barros 1997). A few high-latitude strandings are thought to be extralimital records, and are generally associated with incursions of warm water. These include specimens from Cornwall in England, Cape Province in South Africa, and Maryland, USA (Perryman et al. 1994; Rice 1998).|
Native:American Samoa (American Samoa); Anguilla; Antigua and Barbuda; Aruba; Australia; Bahamas; Bangladesh; Barbados; Belize; Benin; Bermuda; Bonaire, Sint Eustatius and Saba (Saba, Sint Eustatius); Brazil; Brunei Darussalam; Cambodia; Cameroon; Cayman Islands; Cocos (Keeling) Islands; Colombia; Congo; Congo, The Democratic Republic of the; Cook Islands; Costa Rica; Côte d'Ivoire; Cuba; Curaçao; Djibouti; Dominica; Dominican Republic; Ecuador; El Salvador; Equatorial Guinea; Fiji; French Guiana; French Polynesia; Gabon; Gambia; Ghana; Grenada; Guadeloupe; Guam; Guatemala; Guinea; Guinea-Bissau; Guyana; Haiti; Honduras; India; Indonesia; Iran, Islamic Republic of; Jamaica; Japan; Kenya; Kiribati; Liberia; Madagascar; Malaysia; Maldives; Marshall Islands; Martinique; Mauritania; Mayotte; Mexico; Micronesia, Federated States of ; Mozambique; Myanmar; Namibia; Nauru; New Caledonia; Nicaragua; Nigeria; Niue; Northern Mariana Islands; Oman; Pakistan; Palau; Panama; Papua New Guinea; Peru; Philippines; Pitcairn; Puerto Rico; Saint Kitts and Nevis; Saint Lucia; Saint Martin (French part); Saint Vincent and the Grenadines; Samoa; Senegal; Sierra Leone; Singapore; Sint Maarten (Dutch part); Solomon Islands; Somalia; South Africa; Sri Lanka; Suriname; Taiwan, Province of China; Tanzania, United Republic of; Thailand; Timor-Leste; Togo; Tonga; Trinidad and Tobago; United States; Vanuatu; Venezuela, Bolivarian Republic of; Viet Nam; Virgin Islands, British; Virgin Islands, U.S.; Wallis and Futuna; Western Sahara; Yemen
|FAO Marine Fishing Areas:||
Atlantic – eastern central; Atlantic – northwest; Atlantic – southeast; Atlantic – southwest; Atlantic – western central; Indian Ocean – eastern; Indian Ocean – western; Pacific – eastern central; Pacific – northwest; Pacific – southeast; Pacific – southwest; Pacific – western central
|Range Map:||Click here to open the map viewer and explore range.|
This species is relatively common in some areas of its range, such as parts of the Philippines, and is regularly seen in waters around the Hawaiian Islands and around some archipelagos in the western tropical Pacific (such as the Tuamotus-Marquesas Islands). Only a few abundance estimates are available, however.
There are estimates of 45,400 (CV=47%) animals in the eastern tropical Pacific (Wade and Gerrodette 1993); 3,451 (CV = 55%) in the Gulf of Mexico (Mullin and Fulling 2004); 2,947 animals (CV = 111%) in Hawaii (Barlow 2006); and 921 (CV = 80%) in the eastern Sulu Sea, Philippines (Dolar et al. 2006). Photo-identification data from the Hawaiian Islands indicate some site fidelity, with repeated re-sightings of individuals, although movements among the main Hawaiian Islands have been documented (Huggins et al. 2005; Baird pers. comm.).
There is no information on trends in the global abundance of this species.
|Habitat and Ecology:||
Most sightings are from the continental shelf seaward, and around oceanic islands; they are rarely found in temperate waters. However, they do occur in some nearshore areas where deep water approaches the coast (see Watkins et al. 1997; Wang et al. 2001a, b). In the eastern tropical Pacific, the distribution of reported sightings suggests that the oceanic habitat of this species is primarily in the upwelling modified and equatorial waters (Perryman et al. 1994).
Little is known of the diet of this species, though they are known to feed on several species of squid, shrimp and small fish.
Although there is considerable controversy regarding the absolute level of declines, there is good evidence of large-scale reductions in many predatory fish populations (e.g., Baum et al. 2003; Sibert et al. 2006) and over-fishing and collapse of several important “prey” fish stocks world-wide (e.g., Jackson et al. 2001). The effects of such fish population reductions and subsequent ecosystem changes on world-wide populations of melon-headed whales are unknown but could result in population declines.
Predicted impacts of global climate change on the marine environment may affect melon-headed whales, although the nature of impacts is unclear (Learmonth et al. 2006).
Although no regular, large hunts are known, this species is taken occasionally in the subsistence fishery for small cetaceans near the island of St. Vincent in the Caribbean, in Taiwan and in the Japanese dolphin drive fishery. They continue to be taken in a long-lived and well-established harpoon fishery for sperm whales and various small cetaceans near Lamalera, Indonesia. Four melon-headed whales were taken during the 1982 fishing season. Small-boat fisherman also occasionally harpoon or net this species near Sri Lanka and in the Philippines (Jefferson et al. 1993; Perryman et al. 1994). Dolar et al. (1994) investigated the fisheries for marine mammals in central and southern Visayas, northern Mindanao and Palawan, Philippines. Hunters at several sites took melon-headed whales for bait or human consumption. Whales are taken by hand harpoons or, increasingly, by togglehead harpoon shafts shot from modified, rubber-powered spear guns. Around 800 cetaceans of various species are taken annually by hunters at the seven sites, mostly during the inter-monsoonal period of February-May.
Mortality from incidental captures in the purse-seine fishery for yellowfin tuna in the eastern tropical Pacific will probably continue at a very low level (Perryman et al. 1994). Information is scant, but at least small numbers of these pelagic animals are known to be taken in nets throughout the tropics. Especially considering that bycatch of small cetaceans in general is a large and growing problem in Asia (Perrin et al. 2002), low numbers of reports may be misleading. However, no particular conservation problem has been identified.
This species, like other beaked whales, is likely to be vulnerable to loud anthropogenic sounds, such as those generated by navy sonar and seismic exploration (Cox et al. 2006). An anomalous movement of melon-headed whales into a bay in Hawaii was associated with military sonar (Southall et al. 2006), and the frequency of mass stranding events for this species have increased in the last 30 years (Brownell et al. 2006).
Evidence from stranded individuals of several similar species indicates that they have swallowed discarded plastic items, which may eventually lead to death (e.g. Scott et al. 2001); this species may also be at risk.
Predicted impacts of global climate change on the marine environment may affect this species of whale, although the nature of impacts is unclear (Learmonth et al. 2006).
|Conservation Actions:||The species is listed in Appendix II of CITES. Research is needed to assess the impacts of potential threatening processes.|
|Citation:||Taylor, B.L., Baird, R., Barlow, J., Dawson, S.M., Ford, J., Mead, J.G., Notarbartolo di Sciara, G., Wade, P. & Pitman, R.L. 2008. Peponocephala electra. The IUCN Red List of Threatened Species. Version 2014.3. <www.iucnredlist.org>. Downloaded on 30 May 2015.|