Small Cetaceans of the Small Cetaceans of the World:World:

An OverviewAn Overview

Thomas A. JeffersonThomas A. Jefferson

Clymene Enterprises/Cetos Clymene Enterprises/Cetos Research OrganizationResearch Organization

Small Cetaceans of the WorldSmall Cetaceans of the World

Family KogiidaeFamily Kogiidae ““Mini” sperm whales - 2Mini” sperm whales - 2

Family MonodontidaeFamily Monodontidae Arctic whales - 2Arctic whales - 2

Family ZiphiidaeFamily Ziphiidae Beaked whales - 21Beaked whales - 21

Family DelphinidaeFamily Delphinidae Ocean dolphins - 36Ocean dolphins - 36

Family PhocoenidaeFamily Phocoenidae Porpoises - 7Porpoises - 7

Family PlatanistidaeFamily Platanistidae S Asian river dolphin - 1S Asian river dolphin - 1

Family IniidaeFamily Iniidae Amazon River dolphin - 1Amazon River dolphin - 1

Family PontoporiidaeFamily Pontoporiidae Franciscana - 1Franciscana - 1

‘‘Mini’ Sperm WhalesMini’ Sperm Whales

2 species, with largely-overlapping distributions2 species, with largely-overlapping distributions Very poorly-known - most knowledge comes from Very poorly-known - most knowledge comes from

strandingsstrandings Very often confused and misidentifiedVery often confused and misidentified Commonly stranded in some areas of the worldCommonly stranded in some areas of the world

Beluga/NarwhalBeluga/Narwhal

2 species (Arctic only)2 species (Arctic only) Live among the ice floes (Climate change???)Live among the ice floes (Climate change???) Both species heavily hunted by nativesBoth species heavily hunted by natives

Beluga whaleBeluga whale - - DelphinapterusDelphinapterus

Single speciesSingle species Also known as white whale, though young are grayAlso known as white whale, though young are gray Another name is ‘sea canary’Another name is ‘sea canary’ Population in Cook Inlet is endangered and heavily Population in Cook Inlet is endangered and heavily

managed by NMFSmanaged by NMFS

NarwhalNarwhal - - MonodonMonodon

Single speciesSingle species Only species with protruding tuskOnly species with protruding tusk Source of the unicorn mythSource of the unicorn myth Maybe the first cetacean victim of global warmingMaybe the first cetacean victim of global warming

Beaked WhalesBeaked Whales

21 species21 species Most poorly-known group of large mammals in the worldMost poorly-known group of large mammals in the world Currently intensively studied (due to Navy impacts)Currently intensively studied (due to Navy impacts) But, still largely mysterious (due to inconspicuous, But, still largely mysterious (due to inconspicuous,

oceanic habits)oceanic habits)

Baird’s and Arnoux’s beaked Baird’s and Arnoux’s beaked whaleswhales - - BerardiusBerardius

2 species2 species Largest beaked whalesLargest beaked whales Occur in large, tight groupsOccur in large, tight groups Baird’s hunted in Japanese watersBaird’s hunted in Japanese waters Arnoux’s VERY poorly knownArnoux’s VERY poorly known

Bottlenose whalesBottlenose whales - -HyperoodonHyperoodon

2 species (northern and southern)2 species (northern and southern) Northern b w maybe best-studied beaked whaleNorthern b w maybe best-studied beaked whale Supported direct fisheries in E Canada and European Supported direct fisheries in E Canada and European

waterswaters First beaked whales to be subject of focal ecological First beaked whales to be subject of focal ecological

studiesstudies

‘‘Mesoplodonts’Mesoplodonts’ - - MesoplodonMesoplodon

14-15 species (very diverse)14-15 species (very diverse) Males use protruding tusks in competition for femalesMales use protruding tusks in competition for females Some species only known from a few specimensSome species only known from a few specimens Blainville’s b w is now reasonably well-studied (mostly HI Blainville’s b w is now reasonably well-studied (mostly HI

and Bahamas)and Bahamas)

Cuvier’s beaked whale - Cuvier’s beaked whale - ZiphiusZiphius

Single species (cosmopolitan)Single species (cosmopolitan) Known to be capable of very deep dives (at least Known to be capable of very deep dives (at least

87 min, 1,752 m)87 min, 1,752 m) Currently of great interest to US Navy, due to Currently of great interest to US Navy, due to

sonar impactssonar impacts

Longman’s & Shepherd’s beaked Longman’s & Shepherd’s beaked whales -whales - Indopacetus/TasmacetusIndopacetus/Tasmacetus

Single species in each genusSingle species in each genus Indo-Pacific (Longman’s) and Southern Hemisphere Indo-Pacific (Longman’s) and Southern Hemisphere

(Shepherd’s)(Shepherd’s) External appearance unknown until last few yearsExternal appearance unknown until last few years Shepherd’s b w is the only one with a mouth full of teethShepherd’s b w is the only one with a mouth full of teeth Longman’s b w occurs in fairly large schoolsLongman’s b w occurs in fairly large schools

Oceanic DolphinsOceanic Dolphins

36 species (very diverse)36 species (very diverse) Both long-beaked and blunt-headed speciesBoth long-beaked and blunt-headed species Mostly occur in medium to large schoolsMostly occur in medium to large schools Most species are oceanic, but some are coastalMost species are oceanic, but some are coastal

‘‘Snubfin’ DolphinsSnubfin’ Dolphins - - OrcaellaOrcaella

2 species (Irrawaddy and Aus snubfin dolphins)2 species (Irrawaddy and Aus snubfin dolphins) Found only in N Australia and E AsiaFound only in N Australia and E Asia Very coastal in natureVery coastal in nature Highly flexible neck (unusual for a cetacean)Highly flexible neck (unusual for a cetacean)

Killer whaleKiller whale - - OrcinusOrcinus

Single speciesSingle species But wait a minute… taxonomy about to explodeBut wait a minute… taxonomy about to explode Highly diverse, largely based around local prey Highly diverse, largely based around local prey

specializationspecialization Found virtually everywhere there is water connected to the Found virtually everywhere there is water connected to the

oceans (most cosmopolitan marine mammal)oceans (most cosmopolitan marine mammal)

Pilot whalesPilot whales - - GlobicephalaGlobicephala

2 species (short- and long-finned)2 species (short- and long-finned) One is antitropical and one is tropical/warm temperateOne is antitropical and one is tropical/warm temperate Unique body shape with globose head and dorsal fin Unique body shape with globose head and dorsal fin

near the headnear the head Most famous ‘mass strander’Most famous ‘mass strander’

False killer whaleFalse killer whale - - PseudorcaPseudorca

Single speciesSingle species Worldwide dist (not found in high latitudes)Worldwide dist (not found in high latitudes) Occasionally preys on other marine mammals (mostly Occasionally preys on other marine mammals (mostly

dolphins)dolphins) Hawaiian island-associated population recently listed as Hawaiian island-associated population recently listed as

Endangered on US ESLEndangered on US ESL

Pygmy and melon-headed Pygmy and melon-headed whaleswhales - - FeresaFeresa//PeponocephalaPeponocephala

2 species2 species Tropical, oceanic speciesTropical, oceanic species Very similar in external appearance, so much confusionVery similar in external appearance, so much confusion FeresaFeresa occur in small groups and occur in small groups and PeponocephalaPeponocephala in in

large oneslarge ones

Estuarine dolphinsEstuarine dolphins - - SotaliaSotalia

2 species (tucuxi and Guiana dolphins)2 species (tucuxi and Guiana dolphins) Recently split (tucuxi in Amazon River and Recently split (tucuxi in Amazon River and

Guiana dolphin in coastal waters of S America Guiana dolphin in coastal waters of S America [and Orinoco?])[and Orinoco?])

Look a bit like little bottlenose dolphinsLook a bit like little bottlenose dolphins

Humpback dolphinsHumpback dolphins - - SousaSousa

2 species currently (I-P and Atlantic)2 species currently (I-P and Atlantic) Taxonomy is confused - probably at least 4 speciesTaxonomy is confused - probably at least 4 species Found throughout the rim of the Indian Ocean and W Found throughout the rim of the Indian Ocean and W

Pacific, and off W AfricaPacific, and off W Africa Only reasonably well studied in S Africa and Chinese Only reasonably well studied in S Africa and Chinese

waterswaters

Rough-toothed dolphinRough-toothed dolphin - - StenoSteno

Single speciesSingle species Pantropical distributionPantropical distribution ‘‘Reptilean’ appearance, and sloping melonReptilean’ appearance, and sloping melon Probaby very deep diversProbaby very deep divers Appear to be highly intelligent and creativeAppear to be highly intelligent and creative

‘‘Plowshare-headed’ dolphinsPlowshare-headed’ dolphins - - LagenorhynchusLagenorhynchus

6 species (cold temperate waters - antitropical)6 species (cold temperate waters - antitropical) Best known are Pacific WS and dusky dolphinsBest known are Pacific WS and dusky dolphins All have very short beaks and robust bodiesAll have very short beaks and robust bodies Probably going to be split in the futureProbably going to be split in the future Most species not very well studiedMost species not very well studied

Bottlenose dolphins - Bottlenose dolphins - TursiopsTursiops

2 species (worldwide)2 species (worldwide) But there are probably other species as wellBut there are probably other species as well The best-known dolphin in the worldThe best-known dolphin in the world Highly diverse with many local adaptationsHighly diverse with many local adaptations Most common dolphin species in captivity and on TV/in Most common dolphin species in captivity and on TV/in

moviesmovies

Risso’s dolphinRisso’s dolphin - - GrampusGrampus

Single speciesSingle species Found in most areas, but prefer continental slope areaFound in most areas, but prefer continental slope area Adults are covered in scratches, scrapes, and scarsAdults are covered in scratches, scrapes, and scars Easily identifiable, but very few ecological studies have Easily identifiable, but very few ecological studies have

been donebeen done

‘‘Stenellids’Stenellids’ - - StenellaStenella

5 species (mostly tropical)5 species (mostly tropical) Another heterogeneous grouping?Another heterogeneous grouping? Spinner dolphins probably best-known species of genusSpinner dolphins probably best-known species of genus Millions of dolphins of this genus killed in ETP tuna Millions of dolphins of this genus killed in ETP tuna

fishery since 1960sfishery since 1960s

Common dolphinsCommon dolphins - - DelphinusDelphinus

2 species (short- and long-beaked)2 species (short- and long-beaked) Taxonomy split in 1994Taxonomy split in 1994 Mostly temperate, although they do occur in tropicsMostly temperate, although they do occur in tropics Not necessarily all that common in many areas of the Not necessarily all that common in many areas of the

world, esp. equatorial areasworld, esp. equatorial areas

Fraser’s dolphinFraser’s dolphin - - LagenodelphisLagenodelphis

Single speciesSingle species Recently discovered (1956) - external appearance only Recently discovered (1956) - external appearance only

described in 1973described in 1973 Short beak, and very small appendagesShort beak, and very small appendages Still very poorly-known speciesStill very poorly-known species

Right whale dolphinsRight whale dolphins--LissodelphisLissodelphis

2 species (N and S)2 species (N and S) Occur in cold temperate watersOccur in cold temperate waters Unique appearance (eel-like and no dorsal fin)Unique appearance (eel-like and no dorsal fin) Very poorly-known speciesVery poorly-known species One of Tom’s absolute favoritesOne of Tom’s absolute favorites

S HemisphereS Hemisphere dolphins - dolphins - CephalorhynchusCephalorhynchus

4 species (all coastal, restricted ranges)4 species (all coastal, restricted ranges) Smallest of the dolphinsSmallest of the dolphins Short beak, and robust bodiesShort beak, and robust bodies Several species/populations threatened (e.g., Hector’s, Several species/populations threatened (e.g., Hector’s,

Maui’s, Chilean, etc.)Maui’s, Chilean, etc.)

PorpoisesPorpoises

7 species (mostly in colder waters)7 species (mostly in colder waters) Tend to be shy and elusiveTend to be shy and elusive Small and not as social as dolphinsSmall and not as social as dolphins Suffer universal problems with gillnetsSuffer universal problems with gillnets

‘‘Common’ porpoisesCommon’ porpoises - - PhocoenaPhocoena

4 species (2 NH and 2 SH)4 species (2 NH and 2 SH) Mostly relatively coastalMostly relatively coastal Harbor porpoise is the best-known porpoise speciesHarbor porpoise is the best-known porpoise species Spectacled porpoise is the least…Spectacled porpoise is the least… Vaquita is the most endangered cetaceanVaquita is the most endangered cetacean

Dall’s porpoiseDall’s porpoise - - PhocoenoidesPhocoenoides

Single speciesSingle species N Pacific endemicN Pacific endemic Largest porpoise speciesLargest porpoise species Previously caught in N Pacific driftnet fisheriesPreviously caught in N Pacific driftnet fisheries Fast and energetic bowridersFast and energetic bowriders

Finless porpoisesFinless porpoises - - NeophocaenaNeophocaena

2 species2 species Indo-Pacific and narrow-ridged - recently splitIndo-Pacific and narrow-ridged - recently split Only found in Asian/Indian Ocean watersOnly found in Asian/Indian Ocean waters Almost completely unstudied in most areas of rangeAlmost completely unstudied in most areas of range Lots of local adaptation and many different populationsLots of local adaptation and many different populations

River DolphinsRiver Dolphins

3 living species (tropical/temperate regions)3 living species (tropical/temperate regions) 4th species (baiji) was declared extinct in 20064th species (baiji) was declared extinct in 2006 Represent several ancient lineages (not related)Represent several ancient lineages (not related) All have long beaks and lumpy bodiesAll have long beaks and lumpy bodies

South Asian River dolphin - South Asian River dolphin - PlatanistaPlatanista

Single species (but used to be two)Single species (but used to be two) Occur in Ganges/Brahmaputra and Indus basinsOccur in Ganges/Brahmaputra and Indus basins Very bizarre appearance (teeth protrude in old Very bizarre appearance (teeth protrude in old

individuals)individuals) Indus bhulan threatened with extinctionIndus bhulan threatened with extinction

BotoBoto - Inia - Inia

Single speciesSingle species South America (Amazon River)South America (Amazon River) Taxonomy currently being revisedTaxonomy currently being revised Forest dolphin, they can actually swim among treesForest dolphin, they can actually swim among trees Only dolphin with differentiated teeth (molar-like teeth)Only dolphin with differentiated teeth (molar-like teeth)

Franciscana -Franciscana - Pontoporia Pontoporia

Single speciesSingle species Found along E coast of S AmericaFound along E coast of S America Only ‘river dolphin’ that does not live in riversOnly ‘river dolphin’ that does not live in rivers Heavy gillnet mortality and some populations threatenedHeavy gillnet mortality and some populations threatened Subject of many recent studiesSubject of many recent studies

ConclusionsConclusions Wow… there sure are a heck of a lot of species Wow… there sure are a heck of a lot of species

of small cetaceans!!of small cetaceans!! The delphinids have become a taxonomic ‘trash The delphinids have become a taxonomic ‘trash

basket’ - lots of diverse species lumped basket’ - lots of diverse species lumped together.together.

Most of the World’s most endangered cetacean Most of the World’s most endangered cetacean species are small cetaceans, NOT great whales.species are small cetaceans, NOT great whales.

Many species and populations are trouble, often Many species and populations are trouble, often in large part due to lack of knowledge/interest.in large part due to lack of knowledge/interest.

We need to focus much more attention on these We need to focus much more attention on these animals to avoid serious losses of cetacean animals to avoid serious losses of cetacean biodiversity…biodiversity…

Bye bye……

Let’s not say good bye, just see you later……