Short-finned Pilot Whale
Globicephala macrorhynchus
2025 Red list status
Regional Population Trend
Change compared
to 2016
Overview
Globicephala macrorhynchus – Gray, 1846
ANIMALIA – CHORDATA – MAMMALIA – ARTIODACTYLA – DELPHINIDAE – Globicephala – macrorhynchus
Common Names: Short-finned Pilot Whale, Pacific Pilot Whale (English), Kortvinloodswalvis (Afrikaans)
Synonyms: Globicephala macrorhynchus Gray, 1846; Globicephala scammoni Bailey, 1936
Taxonomic Note:
Two morphological forms of Short-finned Pilot Whales (Globicephala macrorhynchus) are found off northern and southern Japan, differing in external and cranial morphology (Kasuya et al. 1988, Van Cise et al. 2016). Although it has been suggested that these might represent two distinct subspecies (Oremus et al. 2009), evidence has not been marshalled to make this distinction official and no subspecies of Short-finned Pilot Whale are currently recognised (Van Cise et al. 2016, Committee on Taxonomy 2024).
Red List Status: LC – Least Concern, (IUCN version 3.1)
Assessment Information
Assessors: Penry, G.,1James, B.S.2 & da Silva, J.3
Reviewer: Purdon, J.4,5
Institutions: 1Nelson Mandela University, 2The Centre for Statistics in Ecology, the Environment and Conservation, University of Cape Town, 3South African National Biodiversity Institute, 4TUT Nature Conservation, 5The Whale Unit, University of Pretoria
Previous Assessors: Cockcroft, V. & Relton, C.
Previous Reviewer: Plön, S.
Previous Contributors: Atkins, S., Child, M.F., Elwen, S., Findlay, K., Meÿer, M. & Oosthuizen, H.
Assessment Rationale
Short-finned Pilot whales (Globicephala macrorhynchus) are a widely distributed species across the globe, where their offshore distribution patterns may overlap with major increasing threats such as long-line fishing, shipping lanes, and seismic exploration activities in the assessment region. Although this species is unstudied in the assessment region, based on strandings and opportunistic sightings data, they appear to be relatively common offshore; and, in other parts of the world, increases in population size have been documented. While the general threats outlined for pelagic species could also apply here, there are no known threats that could cause a range-wide decline. However, there are no population size and trend data for the region of assessment and the taxonomy is uncertain, thus this species will need to be re-assessed as new data emerge. Additionally, as this species is deep-diving, it may be increasingly threatened by the emerging threats of underwater marine noise and plastic pollution, the effects of which should be monitored. Currently, Short-finned Pilot Whales are not conservation priorities within the assessment region as they are globally abundant (for example, 589,000 in the tropical Pacific). Therefore, they are listed as Least Concern.
Regional population effects: Pilot whales presumably occur seasonally in South African waters, and although continued research into their seasonal distribution and movements is required, no barriers to dispersal are recognised, thus rescue effects are considered possible.
Reasons for Change
Reason(s) for Change in Red List Category from the Previous Assessment: No change
Red List Index
Red List Index: No change
Recommended citations: Penry G, James BS & da Silva JM. 2025. A conservation assessment of Globicephala macrorhynchus. In Patel T, Smith C, Roxburgh L, da Silva JM & Raimondo D, editors. The Red List of Mammals of South Africa, Eswatini and Lesotho. South African National Biodiversity Institute and Endangered Wildlife Trust, South Africa.
Regional Distribution and occurrence
Geographic Range
Short-finned Pilot whales are widely distributed with little geographic overlap in their range with Long-finned Pilot Whales (G. melas). The Short-finned Pilot Whales occur in the warm tropics and subtropics, predominantly in deep offshore waters of the North Atlantic, the Pacific and the Indian oceans (Reilly & Shane 1986; Olson 2018), but also commonly occur in northern Angolan waters (Weir 2011, 2019). Within the southern African subregion, they have been recorded from Gabon, Angola, possibly Namibia, South Africa, Madagascar, Réunion, the Comoro Islands, and the Seychelles (Best 2007).
Within the assessment region, van Bree et al. (1978) indicated that Short-finned Pilot Whales are generally restricted to the east coast of South Africa. They presumably range from the east coast of South Africa, southwards to Cape St Francis, Eastern Cape (van Bree 1971), although strandings at Sedgefield, and a skull found near Mossel Bay suggest a slight extension to this westerly limit, most likely due to the southern extension of the warm Agulhas Current on the east coast of southern Africa (Best 2007;Skinner & Chimimba 2005). The most reliable westerly record of G. macrorhyncus off South Africa is from Jeffrey’s Bay (25 °E) (Ross, 1984). This species typically occurs in waters deeper than 1,000 m, beyond the edge of the continental shelf.
Elevation / Depth / Depth Zones
Elevation Lower Limit (in metres above sea level): (Not specified)
Elevation Upper Limit (in metres above sea level): (Not specified)
Depth Lower Limit (in metres below sea level): (Not specified)
Depth Upper Limit (in metres below sea level): (Not specified)
Depth Zone: (Not specified)
Map
Figure 1. Distribution records for Short-finned Pilot Whale (Globicephala macrorhynchus) within the assessment region (South Africa, Eswatini and Lesotho). Note that distribution data is obtained from multiple sources and records have not all been individually verified.
Biogeographic Realms
Biogeographic Realm: Afrotropical, Australasian, Indomalayan, Nearctic, Neotropical, Oceanian, Palearctic
Occurrence
Countries of Occurrence
| Country | Presence | Origin | Formerly Bred | Seasonality |
| American Samoa | Extant | Native | – | Resident |
| Angola | Extant | Native | – | Resident |
| Anguilla | Extant | Native | – | Resident |
| Antigua and Barbuda | Extant | Native | – | Resident |
| Aruba | Extant | Native | – | Resident |
| Australia | Extant | Native | – | Resident |
| Bahamas | Extant | Native | – | Resident |
| Bangladesh | Extant | Native | – | Resident |
| Barbados | Extant | Native | – | Resident |
| Belize | Extant | Native | – | Resident |
| Benin | Extant | Native | – | Resident |
| Bermuda | Extant | Native | – | Resident |
| Bonaire, Sint Eustatius and Saba | Extant | Native | – | Resident |
| Brazil | Extant | Native | – | Resident |
| British Indian Ocean Territory | Presence Uncertain | Native | – | Seasonal Occurrence Uncertain |
| Brunei Darussalam | Extant | Native | – | Resident |
| Cabo Verde | Extant | Native | – | Resident |
| Cambodia | Extant | Native | – | Resident |
| Cameroon | Extant | Native | – | Resident |
| Canada | Extant | Native | – | Resident |
| Cayman Islands | Extant | Native | – | Resident |
| Chile | Extant | Native | – | Resident |
| China | Extant | Native | – | Resident |
| Christmas Island | Presence Uncertain | Native | – | Seasonal Occurrence Uncertain |
| Cocos (Keeling) Islands | Extant | Native | – | Resident |
| Colombia | Extant | Native | – | Resident |
| Comoros | Extant | Native | – | Resident |
| Congo | Extant | Native | – | Resident |
| Congo, The Democratic Republic of the | Extant | Native | – | Resident |
| Cook Islands | Extant | Native | – | Resident |
| Costa Rica | Extant | Native | – | Resident |
| Cuba | Extant | Native | – | Resident |
| Curaçao | Extant | Native | – | Resident |
| Côte d’Ivoire | Extant | Native | – | Resident |
| Djibouti | Extant | Native | – | Resident |
| Dominica | Extant | Native | – | Resident |
| Dominican Republic | Extant | Native | – | Resident |
| Ecuador | Extant | Native | – | Resident |
| El Salvador | Extant | Native | – | Resident |
| Equatorial Guinea | Extant | Native | – | Resident |
| Eritrea | Extant | Native | – | Resident |
| Fiji | Extant | Native | – | Resident |
| French Guiana | Extant | Native | – | Resident |
| French Polynesia | Extant | Native | – | Resident |
| Gabon | Extant | Native | – | Resident |
| Gambia | Extant | Native | – | Resident |
| Ghana | Extant | Native | – | Resident |
| Grenada | Extant | Native | – | Resident |
| Guadeloupe | Extant | Native | – | Resident |
| Guam | Extant | Native | – | Resident |
| Guatemala | Extant | Native | – | Resident |
| Guinea | Extant | Native | – | Resident |
| Guinea-Bissau | Extant | Native | – | Resident |
| Guyana | Extant | Native | – | Resident |
| Haiti | Extant | Native | – | Resident |
| Honduras | Extant | Native | – | Resident |
| Hong Kong | Presence Uncertain | Native | – | Seasonal Occurrence Uncertain |
| India | Extant | Native | – | Resident |
| Indonesia | Extant | Native | – | Resident |
| Iran, Islamic Republic of | Extant | Native | – | Resident |
| Jamaica | Extant | Native | – | Resident |
| Japan | Extant | Native | – | Resident |
| Kenya | Extant | Native | – | Resident |
| Kiribati | Extant | Native | – | Resident |
| Korea, Democratic People’s Republic of | Extant | Native | – | Resident |
| Korea, Republic of | Extant | Native | – | Resident |
| Liberia | Extant | Native | – | Resident |
| Macao | Presence Uncertain | Native | – | Seasonal Occurrence Uncertain |
| Madagascar | Extant | Native | – | Resident |
| Malaysia | Extant | Native | – | Resident |
| Malaysia -> Peninsular Malaysia | Extant | Native | – | Resident |
| Malaysia -> Sabah | Extant | Native | – | Resident |
| Malaysia -> Sarawak | Extant | Native | – | Resident |
| Maldives | Extant | Native | – | Resident |
| Marshall Islands | Extant | Native | – | Resident |
| Martinique | Extant | Native | – | Resident |
| Mauritania | Extant | Native | – | Resident |
| Mauritius | Extant | Native | – | Resident |
| Mayotte | Extant | Native | – | Resident |
| Mexico | Extant | Native | – | Resident |
| Micronesia, Federated States of | Extant | Native | – | Resident |
| Montserrat | Presence Uncertain | Native | – | Seasonal Occurrence Uncertain |
| Morocco | Extant | Native | – | Resident |
| Mozambique | Extant | Native | – | Resident |
| Myanmar | Extant | Native | – | Resident |
| Namibia | Extant | Native | – | Resident |
| Nauru | Extant | Native | – | Resident |
| New Caledonia | Extant | Native | – | Resident |
| New Zealand | Extant | Native | – | Resident |
| Nicaragua | Extant | Native | – | Resident |
| Nigeria | Extant | Native | – | Resident |
| Niue | Extant | Native | – | Resident |
| Norfolk Island | Presence Uncertain | Native | – | Seasonal Occurrence Uncertain |
| Northern Mariana Islands | Extant | Native | – | Resident |
| Oman | Extant | Native | – | Resident |
| Pakistan | Extant | Native | – | Resident |
| Palau | Extant | Native | – | Resident |
| Panama | Extant | Native | – | Resident |
| Papua New Guinea | Extant | Native | – | Resident |
| Peru | Extant | Native | – | Resident |
| Philippines | Extant | Native | – | Resident |
| Pitcairn | Extant | Native | – | Resident |
| Portugal | Extant | Native | – | Resident |
| Puerto Rico | Extant | Native | – | Resident |
| Russian Federation | Extant | Native | – | Resident |
| Réunion | Extant | Native | – | Resident |
| Saint Barthélemy | Extant | Native | – | Resident |
| Saint Helena, Ascension and Tristan da Cunha | Extant | Native | – | Resident |
| Saint Kitts and Nevis | Extant | Native | – | Resident |
| Saint Lucia | Extant | Native | – | Resident |
| Saint Martin (French part) | Extant | Native | – | Resident |
| Saint Vincent and the Grenadines | Extant | Native | – | Resident |
| Samoa | Extant | Native | – | Resident |
| Sao Tome and Principe | Extant | Native | – | Resident |
| Saudi Arabia | Extant | Native | – | Resident |
| Senegal | Extant | Native | – | Resident |
| Seychelles | Extant | Native | – | Resident |
| Sierra Leone | Extant | Native | – | Resident |
| Singapore | Extant | Native | – | Resident |
| Sint Maarten (Dutch part) | Extant | Native | – | Resident |
| Solomon Islands | Extant | Native | – | Resident |
| Somalia | Extant | Native | – | Resident |
| South Africa | Extant | Native | – | Resident |
| Spain | Extant | Native | – | Resident |
| Sri Lanka | Extant | Native | – | Resident |
| Suriname | Extant | Native | – | Resident |
| Taiwan, Province of China | Extant | Native | – | Resident |
| Tanzania, United Republic of | Extant | Native | – | Resident |
| Thailand | Extant | Native | – | Resident |
| Timor-Leste | Presence Uncertain | Native | – | Seasonal Occurrence Uncertain |
| Togo | Extant | Native | – | Resident |
| Tokelau | Presence Uncertain | Native | – | Seasonal Occurrence Uncertain |
| Tonga | Extant | Native | – | Resident |
| Trinidad and Tobago | Extant | Native | – | Resident |
| Turks and Caicos Islands | Extant | Native | – | Resident |
| Tuvalu | Extant | Native | – | Resident |
| United States of America | Extant | Native | – | Resident |
| Uruguay | Presence Uncertain | Native | – | Seasonal Occurrence Uncertain |
| Vanuatu | Extant | Native | – | Resident |
| Venezuela, Bolivarian Republic of | Extant | Native | – | Resident |
| Viet Nam | Extant | Native | – | Resident |
| Virgin Islands, British | Extant | Native | – | Resident |
| Virgin Islands, U.S. | Extant | Native | – | Resident |
| Wallis and Futuna | Extant | Native | – | Resident |
| Western Sahara | Extant | Native | – | Resident |
| Yemen | Extant | Native | – | Resident |
Large Marine Ecosystems (LME) Occurrence
Large Marine Ecosystems: (Agulhas Somali Current Large Marine Ecosystem (ASCLME); Benguela Current Large Marine Ecosystem (BCLME))
FAO Area Occurrence
| Presence | Origin | Formerly Bred | Seasonality | |
| 21. Atlantic – northwest | Extant | Native | – | – |
| 27. Atlantic – northeast | Extant | Native | – | – |
| 31. Atlantic – western central | Extant | Native | – | – |
| 34. Atlantic – eastern central | Extant | Native | – | – |
| 37. Mediterranean and Black Sea | Extant | Native | – | – |
| 41. Atlantic – southwest | Extant | Native | – | – |
| 47. Atlantic – southeast | Extant | Native | – | – |
| 51. Indian Ocean – western | Extant | Native | – | – |
| 57. Indian Ocean – eastern | Extant | Native | – | – |
| 61. Pacific – northwest | Extant | Native | – | – |
| 67. Pacific – northeast | Extant | Native | – | – |
| 71. Pacific – western central | Extant | Native | – | – |
| 77. Pacific – eastern central | Extant | Native | – | – |
| 81. Pacific – southwest | Extant | Native | – | – |
| 87. Pacific – southeast | Extant | Native | – | – |
Climate change
Although the impacts of climate change to Pilot Whales are largely unknown, it is likely that changes in water temperature and CO2 concentration will have cascading effects on Pilot Whale movements and feeding ecology. Learmonth et al. (2006) reported that in the Faroe Islands, where Long-finned Pilot Whales have been historically hunted, catch rates were positively correlated with occurrence of a popular prey species, Todarodes sagittatus. This pelagic squid is thought to be either directly influenced by water temperature and CO2 concentration, or possibly indirectly influenced by productivity (Bjørge 2002). Short-finned Pilot Whales are likely to be similarly affected. Additionally, environmental variation as a result of the 1982–1983 El Niño is likely to have indirectly caused the absence of Short-finned Pilot Whales, and their associated prey-species Loligo opalescens, in some regions.
Cetacean morbillivirus was responsible for the deaths of at least 60 Long-finned Pilot Whales in the Mediterranean (Bellière et al. 2011) with surviving individuals often exhibiting decreased long-term survival due to chronic infections and immunosuppression (Pons et al. 2022). Short-finned Pilot Whales have also been found to contract Cetacean morbillivirus (a family of approximately 30 viruses that affect marine mammals) and at least four individuals stranded off Brazil between July and October 2020 were positive for one of these viruses (Cost-Silva et al. 2023). Such incidents are likely to become more prevalent as the impacts of climate change, especially increasing sea surface temperatures (Sanderson and Alexander, 2020), and ship-avoidance behaviour increase, which may force both species into environments that expose them to new vectors of disease.
Population
No global estimates of abundance exist for Short-finned Pilot Whales; however, several regional population estimates indicate that in certain regions these species are relatively abundant, numbering from the thousands to hundreds of thousands. For example, Wade and Gerrodette (1993) estimated 160,200 Short-finned Pilot Whales in the eastern tropical Pacific, while more recently, Gerrodette and Forcada (2002) estimated 589,000 individuals in the same region. Indeed, Short-finned Pilot Whales have increased significantly in the eastern tropical Pacific from 1986–1990 to 1998–2000 (Gerrodette & Forcada 2002). In summer, south of the Antarctic Convergence, Waring et al. (2006) estimated approximately 200,000 Long-finned Pilot Whales, however this is expected to include some misidentified Short-finned Pilot Whales. No population estimates for Short-finned Pilot Whales are available for the assessment region. Model-based estimates of generation time are 23.5 years for Short-finned Pilot Whales (Taylor et al. 2007).
Current population trend: Increasing
Continuing decline in mature individuals: Unknown
Number of mature individuals in population: Unknown
Number of mature individuals in largest subpopulation: Unknown
Number of subpopulations: Unknown
Severely fragmented: No
Quantitative Analysis
Probability of extinction in the wild within 3 generations or 10 years, whichever is longer, maximum 100 years: (Not specified)
Probability of extinction in the wild within 5 generations or 20 years, whichever is longer, maximum 100 years: (Not specified)
Probability of extinction in the wild within 100 years: (Not specified)
Population Genetics
G. melas and G. macrorhyncus are genetically distinct at the species level, yet within species there are low levels of genetic (mtDNA) diversity reported (Oremus et al. 2009). Despite this evidence two distinct morphological forms have been identified within G. macrorhyncus based on stranded and hunted animals in Japan (Kasuyu et al. 1988; Oremus et al. 2009) – the “Shiho” form in the eastern Pacific Ocean and the “Naisa” form in the central/western Pacific and Indian Oceans as well as the Atlantic Ocean. However, a recent genetic study based on mitogenomes and SNP loci suggests there are three distinct subpopulations, with the Naisa form (or subspecies) actually separated into two diverging subpopulations: one in the Atlantic Ocean and the other in the western/central Pacific and Indian Oceans, separated by the Benguela Barrier off South Africa (Van Cise et al. 2019). As such, two genetically distinct subpopulations are known from the assessment region. Based on this information, the Convention on Biological Diversity’s Global Biodiversity Framework’s (GBF’s) complementary genetic indicator – proportion of populations maintained (PM) – would receive a value of 1.0 (all populations remaining). This is assuming no distinct subpopulations have gone extinct in the region.
While no global or regional population size estimates exist for Short-finned Pilot Whales, estimates from other regions suggest the species is relatively abundant, numbering from the thousands to hundreds of thousands (see Population section). The species would be considered genetically stable if approximately 5,000 individuals or more make up each of the two subpopulations, assuming a conversion ratio of Ne/Nc between 0.1-0.3 (i.e., ne > 500). In general, this is deemed to be feasible, especially considering both subpopulations are likely part of larger subpopulations within their respective waters with no additional barriers to gene flow likely to exist
Habitats and ecology
Short-finned Pilot Whales occur worldwide in tropical, subtropical and warm temperate waters and are present at highest densities over the continental shelf break, continental slope, and areas of high topographic relief. They are also found in deep, oceanographic environments. Although predominantly nomadic, resident populations are documented from the Canary Islands, Madeira Islands, coastal California, and the Hawaiian Islands. This species shows seasonal inshore/offshore movements reflecting that of its prey (squid and mackerel) and they have been recorded diving to depths over 1000 m (Reeves et al. 2003; Mintzer et al. 2008; Santos et al. 2014).
Cephalopods constitute a large proportion of the diet of Globicephala spp., and although fish are also consumed, they are predominantly adapted to a diet of squid. The stomach contents of four Short-finned Pilot Whales stranded at Port Elizabeth, South Africa were comprised of cephalopod remains including Loligo reynaudi and Oregoniateuthis (Ross 1984). Short-finned Pilot Whales perform deep dives, in the same depth range as Sperm and Beaked Whales, during the day and night off the Canary Islands, during which they produce click and buzz sounds associated with foraging (Aguilar de Soto et al. 2008). They also produce tonal and pulsed calls for social communication, with significant differences found between the two species. Short-finned Pilot Whales produce calls of a higher frequency and wider frequency range (mean 7879 Hz) than Long-finned (4480 Hz) and also have distinct group-specific repertoires (Olson 2018).
Pilot Whales are considered extremely gregarious, occurring in average group sizes of 20-90 individuals although some groups can comprise several hundred (Oremus et al. 2009). Short-finned Pilot Whales in southern Africa varied in group size from two to 200 (mean 31.7) (Best 2007). They form strong and stable cohesive bonds with close matrilineal associations that may be an influencing factor in the occurrence of mass stranding events (Perrin & Geraci 2002; Alves et al. 2013). Pilot Whales are frequently observed in mixed-species groups, most commonly in association with bottlenose dolphins (Tursiops spp.). Short-finned Pilot Whales are fairly slow swimmers, and large groups have been recorded stationary on the surface of the water (Mitchell 1975).
Although little is known about the reproductive biology of this species locally, in the northern hemisphere, breeding is seasonal, with births occurring in late summer (July/August) following a gestation period of 14.9 months (Skinner & Chimimba 2005). Female and male mature at an average length of 3.16 m (9 years old) and 4.14 m (16 years), respectively (Skinner & Chimimba 2005). Lactation periods vary greatly in Short-finned Pilot Whales (2 – 1 5 years) but are on average 3.5 -5.5 years (Best 2007). G. macrorhyncus shows a pronounced menopause (about 14 years), presumably driven by the sophisticated culture shown by the species, similarly to Killer Whales, Orcinus orca (Whitehead 2018). This allows for nonreproductive females to provide alloparental care (Kasuya, 1995). They are polygynous and it is thought that males move between female-led groups to mate during temporary aggregations comprising different family groups (Olson 2018)
Ecosystem and cultural services: Marine mammals integrate and reflect ecological variation across large spatial and long temporal scales, and therefore they are prime sentinels of marine ecosystem change (Moore 2008).
IUCN Habitats Classification Scheme
| Habitat | Season | Suitability | Major Importance? |
| 10.1. Marine Oceanic -> Marine Oceanic – Epipelagic (0-200m) | – | Marginal | – |
| 10.2. Marine Oceanic -> Marine Oceanic – Mesopelagic (200-1000m) | – | Suitable | Yes |
| 10.3. Marine Oceanic -> Marine Oceanic – Bathypelagic (1000-4000m) | – | Suitable | Yes |
Life History
(updated from Olsen 2018 & Best 2007)
Generation Length: 23.5 years
Age at Maturity: Female or unspecified: 9 years
Age at Maturity: Male: 17-18 years
Size at Maturity (in cms): Female: 316 cm; southern form
Size at Maturity (in cms): Male: 422 cm
Longevity: Females: 60 years; Males 35-45 years
Average Reproductive Age: (Not specified)
Maximum Size (in cms): Males: 520 cm; Females: 405 cm (Best 2007)
Size at Birth (in cms): 140-185 cm, 55 kg
Gestation Time: 14-16 months
Reproductive Periodicity: 5-7 years
Average Annual Fecundity or Litter Size: (Not specified)
Natural Mortality: (Not specified)
Does the species lay eggs? No
Does the species give birth to live young: Yes
Does the species exhibit parthenogenesis: No
Does the species have a free-living larval stage? No
Does the species require water for breeding? Yes
Movement Patterns
Movement Patterns: (Not specified)
Congregatory: (Not specified)
Systems
System: Marine
General Use and Trade Information
Although pilot whales in the northern hemisphere have been historically exploited for their oil, and are still hunted in regions such as Japan, there is no trade or use of this species within the assessment region.
| Subsistence: | Rationale: | Local Commercial: | Further detail including information on economic value if available: |
| No | – | – | – |
National Commercial Value: No
International Commercial Value: No
| End Use | Subsistence | National | International | Other (please specify) |
| 1. Food – human | – | true | – | – |
| 12. Handicrafts, jewellery, etc. | – | true | – | – |
Is there harvest from captive/cultivated sources of this species? (Not specified)
Harvest Trend Comments: (Not specified)
Threats
Due to their deep-water distribution, pilot whales within South African waters are not expected to experience any major threats that may severely impact their population status in the assessment region. However, additional research into the population status, taxonomy and seasonal movements of these species is needed, following which a reassessment of their conservation status may be necessary. A number of minor threats have been recognised:
Bycatch, particularly in long-line squid fisheries, is a threat to Short- and Long-finned Pilot Whales. There is also a potential emerging threat posed by a southern shift in the distribution of effort by the tuna purse-seine fisheries. It is also possible that there is direct competition between the Long-finned Pilot Whale and the squid fishery, which has been documented in other parts of its range (Minton et al. 2018b), with both species. widely reported to depredate on longline fisheries, removing fish from hooks during operations and losses to fisheries can be substantial (Werner et al. 2015). Pilot whales are particularly susceptible to entanglement in driftnets, but the population-level effect of this mortality is unknown. Although, there is no local information available, commercial squid fisheries are widespread in the western North Atlantic, and the target species for these fisheries are squids commonly eaten by pilot whales, raising the possibility of prey depletion. Bernard and Reilly (1999) suggest that bycatch of pilot whales is likely to be considerably more common than is currently reported.
Similar to beaked whales, both species of pilot whales are thought to be vulnerable to anthropogenic noise pollution, specifically those produced by seismic exploration and navy sonar (Cox et al. 2006; Weir 2008; Antunes et al. 2014) but also increasing levels of commercial shipping and marine construction. Although, the cause of pilot whale mass stranding events remains controversial in many regions, Short-finned Pilot Whales are thought to be frequently impacted by high levels of anthropogenic marine noise (Hohn et al. 2006). As the intensity of marine noise pollution is thought to be increasing within South African waters (Koper & Plön 2012), this potentially represents an emerging threat. Similar to other deep-diving species, marine plastic pollution may also represent an emerging threat, as it has been shown to cause fatalities in sperm whales.
In addition to noise pollution, pilot whales are affected by chemical pollutants; in the north Atlantic long-finned pilot whales were found to have high levels of organochlorine and organobromide contaminants, which may impair reproduction and reduce disease resilience. Being predators at the top of the food chain, pilot whales also accumulate heavy metals such as cadmium and mercury in their meat and blubber and in Japan and the Caribbean the levels were considered unsafe for human consumption (Gajdosechova et al. 2016; Simmonds et al. 2002, Fielding and Evans 2014).
Although the impacts of climate change to pilot whales are largely unknown, it is likely that changes in water temperature and CO2 concentration will have cascading effects on pilot whale movements and feeding ecology. Learmonth et al. (2006) reported that in the Faroe Islands, where Long-finned Pilot Whales have been historically hunted, catch rates were positively correlated with occurrence of a popular prey species, Todarodes sagittatus. This pelagic squid is thought to be either directly influenced by water temperature and CO2 concentration, or possibly indirectly influenced by productivity (Bjørge 2002). Additionally, environmental variation as a result of the 1982–1983 El Niño is likely to have indirectly caused the absence of Short-finned Pilot Whales, and their associated prey-species Loligo opalescens, in some regions.
Disease – The morbillivirus was responsible for the deaths of at least 60 G. melas in the Mediterranean (Bellière et al. 2011) and the impacts of climate change and ship-avoidance behaviour, may force the species into environments that expose them to other vectors of disease. Short-finned Pilot Whales are likely to be similarly affected.
Although pilot whales are hunted in some parts of their range (for example, Long-finned Pilot Whales are caught in “drive-kill fisheries” off Japan and the Faroe Islands, Minton et al. 2018b; Olson 2018), these species are not hunted within the assessment region, and the small-scale exploitation in the southern hemisphere is considered to be irregular (Skinner & Chimimba 2005).
Conservation
Both pilot whale species are listed in Appendix II of CITES and are protected in South Africa under the Threatened or Protected Species (TOPS) regulations that fall within the Marine Living Resources Act (Act 18 of 1998). No specific conservation measures can be recommended for these species within the assessment region until more information on population sizes, trends and threats are generated. As such, they would benefit from continued research into their population dynamics, distribution patterns and the impact of competition and bycatch with local squid fisheries. Globally, too, more research is needed to determine the impact of potential threats on pilot whales (Minton et al. 2018b).
Recommendations for managers and practitioners:
- Interactions between pilot whales and long-line fisheries require urgent investigation. The spatial distribution of squid fisheries and pilot whales should be mapped and overlaps identified. The impacts and severity of potential competition between the fisheries and the cetaceans should be quantified.
Research priorities:
- The severity and potential impacts of threats, specifically the impacts of squid fisheries, could affect the listings of pilot whales.
- It is recommended that population census surveys are undertaken in South African waters, and Marion Island could be used as a monitoring base for G. melas.
- Data pertaining to these species’ distribution patterns and taxonomy is required.
Encouraged citizen actions:
- Use information dispensed by the South African Sustainable Seafood Initiative to make good choices when buying fish in shops and restaurants, e.g. wwfsa.mobi, FishMS 0794998795.
- Save electricity and fuel to mitigate CO2 emissions and hence, the rate of climate change.
- Buy local products that have not been shipped.
- Sightings data from pelagic commercial tourism operators may be particularly valuable.
- Report any strandings to the relevant local authorities.
Bibliography
Aguilar de Soto, N., Johnson, M.P., Madsen, P.T., Díaz, F., Domínguez, I., Brito, A., and Tyack, P. 2008. Cheetahs of the deep sea: deep foraging sprints in short-finned pilot whales off Tenerife (Canary Islands). J. Anim. Ecol. 77, 936–947.
Alves, F., Quérouil, S., Dinis, A., Nicolau, C., Ribeiro, C., Freitas, L., Kaufmann, M., and Fortuna, C. 2013. Population structure of short-finned pilot whales in the oceanic archipelago of Madeira based on photo-identification and genetic analyses: implications for conservation. Aquat. Conserv. 23, 758–776.
Antunes, R., Kvadsheim, P.H., Lam, F.P.A., Tyack, P.L., Thomas, L., Wensveen, P.J., and Miller, P.J.O. 2014. High thresholds for avoidance of sonar by free-ranging long-finned pilot whales (Globicephala melas). Mar. Pollut. Bull. 83, 165–180.
Bellière, E.N., Esperón, F., Fernández, A., Arbelo, M., Muñoz, M.J., and Sánchez-Vizcaíno, J.M. 2011. Phylogenetic analysis of a new Cetacean morbillivirus from a short-finned pilot whale stranded in the Canary Islands. Res. Vet. Sci. 90, 324–328.
Best, P.B. 2007. Whales and Dolphins of the Southern African Subregion. Cambridge University Press.
Bernard, H. J. and Reilly, S. B. 1999. Pilot whales Globicephala Lesson, 1828. In: S. H. Ridgway and R. Harrison (eds), Handbook of marine mammals, Vol. 6: The second book of dolphins and the porpoises, pp. 245-279. Academic Press, San Diego, CA, USA.
Bjørge A. 2002. How persistent are marine mammal habitats in an ocean of variability? In: Raga JA (ed.), Marine Mammals: Biology and Conservation, pp. 63–91. Kluwer Academic/Plenum Publishers, New York, USA.
Committee on Taxonomy. 2024. List of marine mammal species and subspecies. Society for Marine Mammalogy, www.marinemammalscience.org, consulted on 20 February 2025.
Costa-Silva, S., Sacristan, C., Soares, R.M., Carvalho, V.L., Castilho, P.V., Cremer, M.J., Ewbank, A.C., Duarte-Benvenuto, A., Faita, T., Navas-Suarez, P.E., Vieira, J.V., Pereira, L.G., Alves, C.F., Souza, G.C., Lemos, G.G., Silvestre-Perez, N., Catao-Dias, J.L. and L.B. Keid. 2023. Short-finned Pilot Whales strandings associated with Pilot whale Morbillivirus, Brazil. Emerging Infectious Diseases Research Letters 29(1): 214-217
Cox, T.M., Ragen, T.J., Read, A.J., Vos, E., Baird, R.W., Balcomb, K., Barlow, J., Caldwell, J., Cranford, T., Crum, L., D’Amico, A., D’Spain, A., Fernández, J., Finneran, J., Gentry, R., Gerth, W., Gulland, F., Hildebrand, J., Houser, D., Hullar, T., Jepson, P.D., Ketten, D., Macleod, C.D., Miller, P., Moore, S., Mountain, D., Palka, D., Ponganis, P., Rommel, S., Rowles, T., Taylor, B., Tyack, P., Wartzok, D., Gisiner, R., Mead, J. and Benner, L. 2006. Understanding the impacts of anthropogenic sound on beaked whales. Journal of Cetacean Research and Management 7(3): 177-187.
Fielding, R. and Evans, D. W. 2014. Mercury in Caribbean dolphins (Stenella longirostris and Stenella frontalis) caught for human consumption off St. Vincent, West Indies. Marine Pollution Bulletin 89(1): 30-34.
Gajdosechova, Z., Brownlow, A., Cottin, N.T., Fernandes, M., Read, F.L., Urgast, D.S., Raab, A., Feldmann, J., and Krupp, E.M. 2016. Possible link between Hg and Cd accumulation in the brain of longfinned pilot whales (Globicephala melas). Sci. Total Environ. 545, 407–413.
Gerrodette, T. and Forcada, J. 2002. Estimates of abundance of western/southern spotted, whitebelly spinner and common dolphins, and pilot, sperm and Bryde’s whales in the eastern tropical Pacific. NOAA, National Marine Fisheries Service, Southwest Fisheries Center Administrative Report LJ-02-20.
Hohn, A.A., Rotstein, D.S., Harms, C.A. and Southall, B.L. 2006. Multispecies mass stranding of pilot whales (Globicephala macrorhynchus), minke whale (Balaenoptera acutorostrata), and dwarf sperm whales (Kogia sima) in North Carolina on 15-16 January 2005. NOAA Technical Memorandum NMFS-SEFSC-57.
Kasuya, T. 1995. Overview of cetacean life histories: An essay in their evolution. In “Developments in Marine Biology” (A.S. Blix, L. Walloe, and O. Ultang, Eds), vol. 4, pp. 481–497. Elsevier Science, Amsterdam.
Kasuya, T., Miyashita, T. and Kasamatsu, F. 1988. Segregation of two forms of short-finned pilot whales off the Pacific coast of Japan. Scientific Reports of the Whales Research Institute 39: 77–90.
Koper RP, Plön S. 2012. The potential impacts of anthropogenic noise on marine animals and recommendations for research in South Africa. EWT Research & Technical Paper No. 1. Endangered Wildlife Trust, South Africa.
Learmonth, J.A., Macleod, C.D., Santos, M.B., Pierce, G.J., Crick, H.Q.P. and Robinson, R.A. 2006. Potential effects of climate change on marine mammals. Oceanography and Marine Biology: An Annual Review 44: 431-464.
Minton, G., Reeves, R., Braulik, G. 2018a. Globicephala melas. IUCN Red List of Threatened Species. 2018. e.T9250A50356171. doidoi:10.2305/IUCN.UK.2018-2.RLTS.T9250A50356171.en. Retrieved 20 February 2025
Minton, G., Reeves, R., Braulik, G. 2018b. Globicephala macrorhyncus. IUCN Red List of Threatened Species. 2018. e.T9250A50356171. doi:10.2305/IUCN.UK.2018-2.RLTS.T9250A50356171.en. Retrieved 20 February 2025
Mintzer, V.J., Gannon, D.P., Barros, N.B., and Read, A.J. (2008). Stomach contents of mass-stranded short-finned pilot whales (Globicephala macrorhynchus) from North Carolina. Mar. Mamm. Sci. 24, 290–302.
Mitchell E. 1975. Report on the meeting on smaller cetaceans, Montreal. Journal of the Fisheries Research Board of Canada 32: 889-983.
Moore SE. 2008. Marine mammals as ecosystem sentinels. Journal of Mammalogy 89: 534-540.
Olson, P.A. 2018. Pilot whales Globicephala melas and G. macrorhynchus. In: B.Wursig, J.G.M. Thewissen, and K.T Kovacs (eds), Encyclopedia of Marine Mammals 3rd edition, pp. 701-704. Academic Press.
Oremus, M., Gales, R., Dalebout, M.L., Funahashi, N., Endo, T., Kage, T., Steel, D. and Baker, C.S. 2009. Worldwide mitochondrial DNA diversity and phylogeography of pilot whales (Globicephala spp.). Biological Journal of the Linnean Society 98: 729-744.
Perrin, W.F. and Geraci, J.R. 2002. Stranding. In: Perrin WF, Würsig B, Thewissen JGM. (ed.), Encyclopedia of Marine Mammals, pp. 1192–1197. Academic Press, San Diego, California, USA.
Reeves, R.R., Smith, B.D., Crespo, E.A. and Notarbartolo di Sciara, G. 2003. Dolphins, Whales and Porpoises: 2002-2010 Conservation Action Plan for the World’s Cetaceans. IUCN, Gland, Switzerland and Cambridge, UK.
Reilly, S. B. and Shane, S. H. 1986. Pilot whale. In: D. Haley (ed.), Marine mammals of the eastern North Pacific and Arctic waters, pp. 132-139. Pacific Search Press.
Ross GJ. 1984. Smaller cetaceans of the south east coast of southern Africa. Annals of the Cape Provincial Museums. Natural History 16: 309-319.
Santos, M.B., Monteiro, S.S., Vingada, J.V., Ferreira, M., López, A., Martinez Cedeira, J.A., Reid, R.J., Brownlow, A., and Pierce, G.J. (2014). Patterns and trends in the diet of long-finned pilot whales (Globicephala melas) in the northeast Atlantic. Mar. Mamm. Sci. 30, 1–19.
Simmonds, M., Haraguchi, K., Endo, T., Cipriano, F., Palumbi, S. and Troisi, G. 2002. Human health significance of organochlorine and mercury contaminants in Japanese whale meat. Journal of Toxicology and Environmental Health Part A 65(17): 1211-1235.
Skinner, J.D. and Chimimba, C.T. (eds). 2005. The Mammals of the Southern African Subregion. Cambridge University Press, United Kingdom, Cambridge.
Taylor, B.L., Chivers, S.J., Larese, J. and Perrin, W.F. 2007. Generation length and percent mature estimates for IUCN assessments of cetaceans. NOAA, Southwest Fisheries Science Center Administrative Report LJ-07-01. La Jolla, California.
Wade, P.R. and Gerrodette, T. 1993. Estimates of cetacean abundance and distribution in the eastern tropical Pacific. Reports of the International Whaling Commission 43: 477-493.
Waring, G.T., Josephson, E., Fairfield, C.P. and Maze-Foley, K. 2006. U.S. Atlantic and Gulf of Mexico marine mammal stock assessments – 2005. NOAA Technical Memorandum NMFS-NE-201. 346 p.
Weir CR. 2008. Short-finned pilot whales (Globicephala macrorhynchus) respond to an airgun ramp-up procedure off Gabon. Aquatic Mammals 34: 349–354.
Weir, C.R. 2011. Distribution and seasonality of cetaceans in tropical waters between Angola and the Gulf of Guinea. African Journal of Marine Science 33(1): 1-15.
Weir, C.R. 2019. The cetaceans (whales and dolphins) of Angola. In Biodiversity of Angola: Science & Conservation: A modern Synthesis. Eds B.J. Huntley, V. Russo, F. Lages, and N. Ferrand. Springer Nature, New York, N.Y. pp 445-470.
Werner, T., Northridge, S., McClellan Press, K., and Young, N. (2015). Mitigating bycatch and depredation of marine mammals in longline fisheries. ICES J. Mar. Sci. 72, 1576–1596.
van Bree PJH, Best PB, Ross GJB. 1978. Occurrence of the two species of pilot whales (genus Globicephala) on the coast of South Africa. In: F.A.O. Advisory Committee on the Marine Resources Research (ed.), Scientific consultation on Marine Mammals. Bergen.
van Bree PJH. 1971. On Globicephala seiboldi Gray, 1846, and other species of pilot whales (Notes on Cetacea, Delphinioidae III). Beaufortia 19: 79–87.
Van Cise, A.M., Baird, R.W., Baker, C.S., Cerchio, S., Claridge, D., Fielding, R., Hancock-Hanser, B., Marrero, J., Martien, K., Mignucci-Giannoni, A.A., Oleson, E.M., Poole, M.M., Rosel, P.E., Taylor, B.L. and P.A. Morin. 2019. Oceanographic barriers, divergence, and admixture: Phylogeography and taxonomy of two putative subspecies of short-finned pilot whales. Molecular Ecology 28(11): 2886-2902.