Category: marine mammal

Manatees and the Dugong

Dogong credit Niklas Findt
Amazon manatee
West african manatee
West Indian Manatee

Dugong and Manatees

The family Sirenia consists of 2 genus, the Dugongidae (only extant species is the Dugong)  and  Trichechidae which contains the 3 Manatee species.

The Dugong is the species in the top left (if you cannot pick it out). The Steller sea cow was a close relation of the Dugong

The big difference, is that unlike Manatees with a paddle shaped tail, where as Dugongs have fluked tails.

As always, as links are made to help with tourism, these will either appear below, or each species will be spun off to have its own page. Ecotourism need not have a big impact on the species and its natural behaviour, however, by giving them financial value to the local population you greatly increase the liklihood of survival as well as increasing the standard of living for local people.

 Should you work in tourism dealing with these species, do get in touch, there is a link at the top of the home page, with a simple form.

Dugong– The only surviving Dugongidae after the stellers sea cow (described in 1741 and hunted to extinction by 1768 for hide meat and fat) was lost.

It is found in the waters of around 37 countries in the Indo-west Pacific. It has recently become functionally extinct in Chinese waters, and may well be lost entirely in the near future. Its thought that while their current range is highly fractured, it is probably still a similar limit to before. These countries between them, give around 140,000km of coastline, and this area maps with where the correct species of sea grasses grow. The worldwide population is thought to have declined 20% in the last 90 years, though this is pretty good compared to many other species.

There are currently thought to be 100,000, with its conservation status being Vulnerable

Amazonian Manatee-Found in parts of the Amazon basin, throughout parts of Brazil, Colombia Peru and Ecuador.

It is the smallest of the surviving Manatees. Weights fall between 7,5kg and 350kg, with a 75cm-225cm length.  Given that it is likely decreasing, it is going to be below this now.

They are exclusively herbivorous, feeding on water lettuce and hyacinth. During a day, they can consume around 8% of their bodyweight. This mostly occurs during the wet season, during the dry season they return to the main river and survive on their fat reserves. They have a prehensile snout (like a less developed trunk) for feeding

They are considered Vulnerable, with the last count giving an upper limit of 10,000, however, this was in 1997. 

West-Indian manatee- So named,  because they were first sighted amongst a group of Islands called the West-Indies in the Caribbean – it is no-where near India (as you can see).  They live in shallow coastal areas. They have a prehensile snout (like a less developed trunk) for feeding. Unlike elephants, they are not limited to 6 sets of teeth, but only having molars (24-36) it is a simpler layout. As their range includes Florida (well known from the Everglades) this species is well known in places. They are hard to count, living in murky water,

Listed as vulnerable, the whole population is not thought to be greater than 10,000. The 2 subspecies are the Florida manatee (around 2500) and the Antillean Manatee which is found off the Atlantic coast of Mexico and central south America (particularly in the waters of greater Antilles) potentially, historically found along the coast of Texas (and as far north as Dennis, Tennessee).

African Manatee- (or West African Manatee) Although found both on the coast and inland, there is no significant genetic difference between these populations. African Manatees can be found in West African regions which include a wide range of countries – requiring cross nation action to save them. Manatees are found in brackish waters to freshwater: in oceans, rivers, lakes, coastal estuaries, reservoirs, lagoons, and bays on the coast.

The areas with the highest manatee populations are Guinea-Bissau, the lagoons of Côte d’Ivoire, the southern portions of the Niger River in Nigeria, the Sanaga River in Cameroon, the coastal lagoons in Gabon, and the lower parts of the Congo River. Alone amongst manatee species, the African manatee is Omnivorous, eating clams and molluscs as well as fish found in nets (can make up 50% of diet). They are more adaptable than other manatees, being able to survive in salt water (though they need access to fresh water to drink).

They are nocturnal, but many countries, a dead manatee is worth a lot to hunters. They are listed on CITES Appendix 1 with a population under 10,000. Cote d’Ivoire has a population of 750-800. Some of the biggest populations still live in Gabon, status is unknown in many areas. There is much tourism potential – worth a lot in Florida.

 

Beaked whales

Beaked whales

Beaked whales are a fascinating wide-ranging family. There are 24 species, but they spend much of their time in the ocean depths, and are capable of holding their breath for up to 3 hours.

More amazingly, it appears that some species might only spend several minutes at the surface before returning to the depths. Now, while this 3 hours record dive is repeatable is a big question. Assuming the beaked whale was capable of repeating this 8 times in a 24 hour period, we would be talking about a species which spends only 1% of its time at the surface. Given their shape also allows them to keep an incredibly low profile, even at the surface – and we do not know how many of them there are, it makes it clear how hard it would be to spot one.

If you could sit in one place, in the ocean for 24 hours, and have a whale repeatedly return to the surface for 2 minutes, half a mile away, it would not be hard to miss the animal.

Please note, where I have found a video, it is in line with the correct image. Before you reach all these species, there is an amalgamated news section for all beaked whales.

We are eager to support tourism of these species, but given they are seen so rarely, there is not a great deal of tourism connected to them. However, we will happily list anyone who does work in tourism and sees one of these even once (we will also list you on pages for cetaceans that you see more regularly.

Arnoux beaked whale Genus Beradius

Also known as the southern 4 toothed whale, southern beaked whale, New Zealand beaked whale, southern giant bottlenose whale and southern porpoise whale is one of the species of Berardius. This species and the one below, is so similar that only genetic evidence and the huge distance between them convinced people they were separate species. 

Little is known about them, because they are encountered so rarely

Play Video

Baird Beaked whale Genus Beradius

Also known as the northern giant bottlenose whale, North Pacific bottlenose whale, giant four-toothed whale, northern four-toothed whale and the North Pacific four-toothed whale, is a species of whale from the genus Beradius. It is the second largest toothed whale after the Sperm Whale

Play Video

Sato Beaked whale Genus Beradius

This whale was only recognized as a separate species on the basis of mtDNA. Its beak is usually only around 4% of body length. The name comes from the researcher who defined it (from pictures on land.

They generally have many scars, which are easy to see, as their skin is dark and the scars light to white.

Its classed as near threatened, though its hard to know.

Subfamily Hyperodontinae, Genus Hyperoodon – bottlenose whales, northern bottlenose whale The northern bottlenose whale was hunted heavily by Norway and Britain in the 19th and 20th centuries. It is capable of diving incredibly deep, with recorded dives reaching 2339m, and has been timed staying under water for 130 minutes. The northern bottlenose whale is endemic to the North Atlantic Ocean< and populations are found in the deep (500 m) cold subarctic waters of the Davis Strait, Labrador Sea, Greenland Sea, Barents Sea, , but can range as far south as Newfoundland and Nova Scotia. As of 2017, the population in the North East Atlantic is estimated to be between 10,000 and 45,000.

Subfamily Hyperodontinae, Genus Hyperoodon – bottlenose whales, Southern bottlenose whale

The southern bottlenose whale is a species of whale, in the Ziphiid family, one of two members of the genus Hyperoodon. Seldom observed, the southern bottlenose whale is resident in Antarctic waters. The species was first described by English zoologist William Henry Flower in 1882, based on a water-worn skull from Lewis Island, in the Dampier Archipelago, Western Australia. They live in deep ocean waters over 1000 meters.

Gnerally their dives last 15-40 minutes, but it is unclear if they would be capable of diving for as long as the northern species. There are no population estimates, though they make up 90% of ziphiid sightings in Antarctic waters.

Subfamily Hyperodontinae, Genus Indopacetus, Tropical bottlenose whale

The tropical bottlenose whale, also known as the Indo-Pacific beaked whale or Longman’s beaked whale, was considered to be the world’s rarest cetacean until recently, but the spade-toothed whale now holds that position. As of 2010, the species is now known from nearly a dozen strandings and over 65 sightings. This is the only species in its genus.

Given how rarely they are sighted, they have not been hunted, though they have been killed accidently.

Andrews' beaked whale

Subfamily Hyperodontinae, Genus Mesoplodon, mesoplodont whales, Andrews Beaked whale

Subfamily Hyperodontinae, Genus Mesoplodon, mesoplodont whales Blainvilles beaked whale

Blainville's beaked whale

Subfamily Hyperodontinae, Genus Mesoplodon, mesoplodont whales Deraniyagala beaked whale

The Deraniyagala beaked whale is so rare, I have been unable to find a video to place here

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Subfamily Hyperodontinae, Genus Mesoplodon, mesoplodont whales, Gervaiss beaked whale

Gervais's beaked whale
Ginkgo-toothed beaked whale

Subfamily Hyperodontinae, Genus Mesoplodon, mesoplodont whales,

Ginkgo-toothed beaked whlae

Subfamily Hyperodontinae, Genus Mesoplodon, mesoplodont whales, grey beaked whale

grey beaked whale
Hector's beaked whale

Subfamily Hyperodontinae, Genus Mesoplodon, mesoplodont whales, Hectors beaked whale

Subfamily Hyperodontinae, Genus Mesoplodon, mesoplodont whales, Hubbs Beaked whale

Hubbs' beaked whale
Perrin's beaked whale

Subfamily Hyperodontinae, Genus Mesoplodon, mesoplodont whales, Perrins beaked whale

Subfamily Hyperodontinae, Genus Mesoplodon, mesoplodont whales, Pygmy beaked whale

Pygmy beaked whale
Ramari's beaked whale

Subfamily Hyperodontinae, Genus Mesoplodon, mesoplodont whales

Subfamily Hyperodontinae

Sowerby's beaked whale
Spade-toothed whale

Subfamily Hyperodontinae

Subfamily Hyperodontinae

Stejnegers beaked whale
Strap-toothed whale

Subfamily Hyperodontinae

Subfamily Hyperodontinae

True's beaked whale

Orca or Killer whales

Orca by Robert Pittman NOAA

Orca or Killer whale

As this species is a member of Cetacea, not carnivora. Never-the-less, this is the largest clear predator on the planet.

They are found in all of the worlds oceans. What is incredible, is that other apex predators, like the great white are rendered prey, simply be the arrival of Orcas on the scene.

One such example, is the arrival of the Orcas in South Africa. The great white sharks have vanished. While there are suggestions that they have not gone far (perhaps merely into the depths of the waters nearby)  it is clear that after a number were killed by the orcas they have given way.

They are not actually whales, being the largest member of the Oceanic Dolphin family, and as such appear to have the brainpower to defeat almost anything when they put their mind to it. As well as great white sharks, Orca will also hunt all of the baleen whales, including the blue whale which is the largest animal to ever roam the earth. They will also regularly hunt toothed whales such as false killer whales.

Each pod is lead by a dominant female, and these animals can live to be 50-90 years old. While this species eats a wide variety of fish, sharks, rays and marine mammals such as seals, other species of dolphins and whales, generally these animals specialize. Some generally eat fish, while others hunt mammals.

They have a wide range of hunting techniques, from polar orca working together to create waves to wash seals off icebergs, to intentionally beaching themselves in Argentina, to grab seals from the beach. Each group is capable of coming up with their own techniques which are taught to future generations.

Below you will find any articles from the blog, which mention the Killer whale (or Orca). Below that is a video of this species (it is a 50 minute documentary on this species). Below that, we will add any links which will allow you to try to see this species for yourself.

Southern right-whale dolphin

Southern right whale dolphin by Alcide Dessaines D' Orbigny

Southern right-whale dolphin

The southern right whale dolphin  is a small and slender species

 

 of cetacean, found in cool waters of the Southern Hemisphere. It is one of two species of right whale dolphin. This genus is characterized by the lack of a dorsal fin. The other species, the northern right whale dolphin, is found in deep oceans of the Northern Hemisphere and has a different pigmentation pattern than the southern right whale dolphin.

Southern right whale dolphins can be easily distinguished from other cetacean species within their range as they are the only dolphins without dorsal fins in the Southern Hemisphere. They have streamlined and graceful bodies, a single blowhole and a short and defined beak, possessing between 39 and 50 teeth per row.

A sharp dividing line separates the black dorsal part from the white ventral part of the body, running from the tail stock forward,  dipping down to the flipper insertion and sweeping back up, below the eyes, to cross the melon between the blowhole and snout crease. Younger individuals can be grey/brownish dorsally but develop adult coloration within the first year. The flippers of the southern right whale dolphins are small, recurved, predominantly white and located about one-quarter of the way back from the snout tip. Their flukes are small, have a white underside and dark grey upper side, with a notch in the middle and concave trailing edges.

There are no current global abundance and mortality estimates of the species although it is considered a fairly common and abundant species along its range, particularly in Chile. The very low sighting rate is most likely caused by a lack of sampling effort and due to the difficulties of sighting the animals in their offshore habitat.

Northern right-whale dolphin

Northern rhight whale dolphin

The northern right whale dolphin is a small, slender species of cetacean found in the cold and temperate waters of the North Pacific Ocean. Lacking a dorsal fin, and appearing superficially porpoise-like, it is one of the two species of right whale dolphin.

Northern right whale dolphins are fast swimmers. Their average swimming speed is around 26 km/h (16 mph) but they can reach speeds of up to 30–40 km/h (19-25 mph).
When travelling fast, a group looks as though they are bouncing along on the water, as they make low, graceful leaps together, sometimes travelling as far as 7 m in one leap. They can dive up to 200 m (660 ft) deep in search of squid and fish, especially lanternfish. Additionally,  also feeds on other prey items, such as Pacific hake, saury and mesopelagic fish.

It is estimated that a total of around 68,000 northern right whale dolphins inhabit the Pacific Ocean. Of those, around 26,000 (the geometric mean of their abundance estimates in US waters from 2008-2014) are placed into the California/ Oregon/ Washington stock for management purposes. Their minimum population estimate is around 18,600. Their abundances and distributions along the US coast do not only vary seasonally but also interannually, making the identification of population trends difficult.

Below is a list of any articles from this site, which mentions this species. Below that, is a video of the species in question. Below both of these we hope to add links which will help if you are looking to see this animal in the wild.

Hectors Dolphin

Hectors Dolphin photo by Avenue

Hectors Dolphin

Hector’s dolphin  is one of four dolphin species belonging to the genus Cephalorhynchus. Hector’s dolphin is the only cetacean endemic to New Zealand, and comprises two subspecies: C. h. hectori, the more numerous subspecies, also referred to as South Island Hector’s dolphin; and the critically endangered Māui dolphin (C. h. maui), found off the West Coast of the North Island.

It is the smallest dolphin species with adults length between 1.2 and 1.6m. The species’ range includes murky coastal waters out to 100 m (330 ft) depth, though almost all sightings are in waters shallower than 50 m (160 ft). Hector’s dolphins display a seasonal inshore-offshore movement; favouring shallow coastal waters during spring and summer, and moving offshore into deeper waters during autumn and winter. They have also been shown to return to the same location during consecutive summers, displaying high foraging site fidelity. The inshore-offshore movement of Hector’s dolphins are thought to relate to seasonal patterns of turbidity and the inshore movements of prey species during spring and summer.

There are 2 subspecies,

  • South Island Hectors dolphin – Threatened, and with a decreasing population, currently thought to number around 10,000
  •  Maui dolphin – critically endangered, population under 50.
These diverged 50,000-60,000

Below, you will see a list of articles on this subject, and below that, you will see a video on this species

Below both of these, we will add links and information (as we get it) so that you can see these dolphins if you are in the area.

Haviside Dolphin

Haviside dolphin by Joachim Huber

Haviside Dolphin

Heaviside’s dolphin is one of four dolphins in the genus Cephalorhynchus. The small cetacean is endemic to the Benguela ecosystem along the southwest coast of Africa. Heaviside’s are small and stocky with adults reaching a maximum length of 1.7m and weight of75 kg. The dolphin has a distinct black, grey and white body pattern, making it hard for it to be confused with any other dolphin found in the same waters. The head is cone shaped with a blunt beak. The dorsal fin is triangular in shape and centred in the middle of the back. The head and thorax are coloured light grey with darker patches around the eye. The dorsal fin,& fluke and dorsal cape are a dark grey to almost black with a band that extends forward from the dorsal fin to the blowhole. The underbelly is white, with bands that extend onto the lower rear of the body. Small white patches are located just behind the pectoral fins and a single white patch extends between these fins on the chest. Sexual dimorphism is minimal, however variation in the shape of the white patch covering the genital slit is distinct between genders. In males, the patch ends in a point, but in females widens out to cover the mammary slits.

Information on reproduction is limited for Heaviside’s dolphins, however they are thought to be comparable to Hector’s and Commerson’s dolphins. Females and males reach sexual maturity approximately between 5–9 years. Mating is thought to occur year-round, however individual females may only produce calves every 2–4 years. Gestation time is unknown. Maximum known lifespan is based on the oldest recorded individual at 26 years old. Levels of predation are unknown, however killer whales(Orcinus orca) are known predators and there is evidence of shark attack from body scars.
Heaviside’s have small home ranges of 50–80km as measured using satellite telemetry over 2–3 months and photographic resighting over up to 3 years.

 Some individuals have been resighted at the same location for up to 10 years. Prior to 2018, the “International Union for Conservation of Nature” International Union for Conservation of Nature (IUCN) listed the Heaviside’s as ‘Data Deficient’ however, as of 2017 the status was changed to ‘Near Threatened’, owing to improved knowledge on the species from multiple studies. Despite this, the overall population trend remains unknown, and there are many aspects of the species biology that remain to be studied. Heaviside’s dolphin is listed on Appendix II of the “Convention on the Conservation of Migratory Species of Wild Animals” Convention on the Conservation of Migratory Species of Wild Animals Memorandum of Understanding Concerning the Conservation of the Manatee and Small Cetaceans of Western Africa and Macaronesia. Memorandum of Understanding Concerning the Conservation of the Manatee and Small Cetaceans of Western Africa and Macaronesia. The Memorandum of Understanding was established in 2008 and aims to protect these species at a national, regional and global level.

Below here is a video of some of these dolphins, and below that is our usual list of articles on this species (we hope this number will increase in the near future).

Below this, we will add links for you to go and see these dolphins for yourself

Commerson Dolphin

Commison Dolphin

Commerson’s dolphin  (also known as  jacobita, skunk dolphin, piebald dolphin, panda dolphin, or tonina overa (in South America), is a small oceanic dolphin of the genus Cephalorhynchus. The dolphin takes its name from the  French naturalist Dr Philibert Commerson, who first described them in 1767 after sighting them in the Strait of Magellan. To the right of this is a map of the Primary subspecies, the secondary subspecies lives a large distance out into the Indian ocean.

There are two geographically-isolated but locally-common subspecies. The principal subspecies, C.c.commersonii, has sharply-delineated black-and-white patterning and is found around the tip of South America. The secondary subspecies, C.c.kerguelenensis, is larger than C.c.commersonii, has a less-sharply delineated dark and light grey patterning with a white ventral band, and is found around the Kerguelen Islands in the Indian Ocean.

Commerson’s dolphin is very active. It is often seen swimming rapidly on the surface and leaping from the water. It also spins and twists as it swims and may surf on breaking waves when very close to the shore. It will bow-ride and swim behind fast-moving boats. It is also known to swim upside-down, which is thought to improve the visibility of its prey.

This dolphin feeds on a mix of coastal and pelagic fish and squid. Those in the South American subpopulation supplement their diets with crustaceans Individuals have been recorded as entering the Santa Cruz River to forage there during low tide. They can be found in estuaries, especially during the breeding season.
The IUCN lists Commerson’s dolphin as Least Concern in its Red List of Threatened Species. The proximity of the dolphin to the shore makes accidental killing in Gillnet a common occurrence. The dolphin was killed for use as crab Bait (luring substance) by some Argentinian and Chilean fishermen in the 1970s and 1980s, but this practice has since been curtailed. The Commerson’s dolphin population of South America is listed on Appendix II of the “Convention on the Conservation of Migratory Species of Wild Animals” Convention on the Conservation of Migratory Species of Wild Animals. It is listed on Appendix II as it has an unfavourable conservation status or would benefit significantly from international co-operation organised by tailored agreements.

There are a few of these dolphins in captivity.

Below is a video (there are clearer captive videos do have a look) below that will be a list of any stories on this species

Below that, I will add any links to people who can help you see these species in the wild.

White-beaked dolphin

White beaked dolphin

The white-beaked dolphin  is a marine mammal belonging 

to the family Delphinidae (oceanic dolphins) in the sub order Odontoceti (toothed whales). Their distribution is shown in the map.

The white-beaked dolphin is endemic to the cold temperate and subarctic waters of the North Atlantic Ocean, most commonly in seas less than 1,000 m (3,300 ft) deep. Due to the fact they are not fully adapted to Arctic conditions, they are more vulnerable to predators, most notably polar bears. Within this wider region, white-beaked dolphins are most commonly found in four locales: on the Labrador Shelf close to southwestern Greenland, around Iceland, off the northern and eastern coasts of Britain, and off the coast of Norway. In the Faroe Islands between Iceland and the United Kingdom the White-beaked dolphin is at risk of being hunted during drive catches of the long-finned pilot whales. They may also be incidentally trapped in the purse-sein and trawl nets of the area. There are no recognised subspecies.

The dolphin may easily be misidentified as the Atlantic white-sided dolphin, although the white-beaked is commonly found further north. The white-beaked dolphin is also typically larger, and does not have yellow streaks on its side.

Below is a video (no sound) of them filmed under water off the coast of the UK. Northern parts of the UK have populations, including Lyme bay and areas around the hebrides.

They are thought to number 100,000, so are listed as least concern.

Pacific white-sided dolphin

Pacific white-sided dolphin

The Pacific white-sided dolphin, also called the hookfin porpoise, is an active dolphin found in the cool or temperate waters of the North Pacific Ocean.

The Pacific white-sided dolphin was named by Smithsonian mammalogist Theodore Nicholas Gill in 1865. It is morphologically similar to the dusky dolphin, which is found in the South Pacific.[6] Genetic analysis by Frank Cipriano suggests the two species diverged around two million years ago.

Though traditionally placed in the genus Lagenorhynchus. Molecular analyses indicate they are closer to dolphins of the genus Cephalorhynchus, in the Lissodelphininae subfamily, than to both the Atlantic white-sided dolphin and the White-beaked dolphin. It has therefore been proposed to move the Pacific white-sided dolphin to the resurrected genus Sagmatias together with other southern hemisphere species (hourglass dolphin, Dusky dolphin and Peale’s dolphin).  However, there is still some analysis to do, before this move can take place.  White-sided dolphins swim in groups of 10 to 100, and can often be seen bow-riding and doing somersaults. Members form a close-knit group and will often care for a sick or injured dolphin. Animals that live in such large social groups develop ways to keep in touch, with each dolphin identifying itself by a unique name-whistle. Young dolphins communicate with a touch of a flipper as they swim beside adults.

United Nations banned certain types of large fishing nets in 1933, many Pacific white-sided dolphins were killed in drift nets. Some animals are still killed each year by Japanese hunting drives

There are around 100 in dolphinarias in the USA and Japan. They are currently listed as least concern

Below is a list of any articles on the species, and below that a video of it. Under this, I will add any links that might help you see this species in the wild.

See Animals Wild