Tag: Sperm whale

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Sperm whales make direction decisions democratically

Researchers have found that sperm whales decide on which way to turn democratically. While these whales only socialize with members of their own clan. You might think that this might restrict them, but generally clans have 20,000 females, making these groups huge (one of the distinguishing marks of the clan is by vocal dialects – which may end up as symbolic markers of the clan identity).

When travelling in a group they can take over 1 hour to decide which way to turn. These groups can be extremely large, and yet decide things together. Decisions like direction and speed of travel and also when to feed. While it is not clear how they reach consensus or how they “speak” to each other, it is clear that decisions are made together.

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Sperm whales can take over an hour to decide together which way to go

Family of spermwhales underwater near water surface, shot from below photo credit italy sokol-dbw8sol

Generally, only spending time with their clan (numbering around 20,000), it seems that decisions about where to go, are made cooperatively in a democratic way.

Taking up to an hour to make the decision about the direction of travel, they can often travel in large groups making communal decisions about destination, route and speed, as well as when to feed and what to do about predators.

Some of these clans live over large areas, split by as much as thousands of kilometres, and it is thought to be akin to language forming in humans. Interestingly, these clans can share areas of the sea, but will only spend time with other members of their clan. Social units within clans, are based around the females, with each unit consisting of around 10 females with their offspring. These become very close, with other females babysitting young while their mothers make deep dives to feed – even suckling is done as a group.

The sperm whale has a brain which is thought to be larger than any other animal to ever live.

Over a million were killed for their very pure oil, between 1712 and 1982. There are thought to be around 300,000 in the worlds oceans, however, before whaling it is thought that there were 1.1 million.

Pygmy Sperm Whale

 The Pygmy sperm whale is one of just two species from the Superfamily Kogiidae, the other one being the Sperm whale. They are seen very rarely, with the majority of the knowledge about them, coming from carcasses that wash up on the beach. It was first described in 1834 based on a skull that washed up on the coast of france in 1784 (50 years earlier). While originally placed in the same genus as the sperm whale, it was moved to its own genus Kogia, as it is actually a species which is half way between the dolphins and the sperm whale.

They grow to around 3.5m, which is smaller than many dolphin species.

It has a far smaller brain than the sperm whale (even by comparison size) which my explain why it has such a lot more simple social life.

Pygmy sperm whales are found throughout the tropical and temperate waters of the Atlantic, Pacific, and Indian Oceans, though there are also seen regularly off Russia. Fossils in Japan, Italy South Africa have been found, suggesting that they were more widely spread. The problem is, that seen rarely at sea, and with most of what we know about coming from carcasses, we have little idea if dead and dying animals behave differently to healthy ones.

Seen rarely, I have been unable to find out how long they can hold their breath, though as the sperm whale can hold its breath for 90 minutes, so its likely that the pygmy sperm whale is also an impressive breath holder – this would explain why they are seen so rarely.

Whales, Dolphins and Porpoises family tree

Cetaceans -Whales, porpoise and dolphins

Few people can avoid stopping to watch, if they spot cetaceans from a cliff. While the family is wide and varied, they are all pretty interesting. From some of the largest and most intelligent hunters such as killer whales to the largest animal on earth the blue whale.

Whale and dolphin watching tourism is worth a lot of money – this can be essential, as in many places the extra money helps a community survive. 

I hope, overtime, to make this section of the website as large a list of places to view cetaceans and people who will help you in that quest.

As might perhaps be suspected, all of the mammal species which have returned permanently to the sea, and developed breathing holes located on their back (and therefore perfectly placed for taking quick breaths) are  related.

So what is the most closely related living land mammal? Perhaps obviously, it is a species which spends much time in the water – the hippopotamus.

As with all of these pages, as we create pages for each individual species, they will be linked to the photo below.

So the baleen whales are split into three families, these are not large as there are only 16 species of baleen whales in the world. At the current time, there are roughly 1.1 million baleen whales in the worlds oceans

Below is a family tree of the group

 

Baleen Whales

Baleenideae – the rhight whales

 

The first  living split is Baleenidae, this family is not huge. The north atlantic and north pacific are closest related, these species are closely related to the Southern pacific right whales. Their name is unfortunate – it is called right whale for 3 reasons, it swims slowly, floats when dead and carries a large amount of oil. This lead to all these species being hunted close to extinction.

North Atlantic right whale
North pacific right whale
Southern right whale
Bowhead whale

The other family is called Balaenopteroidea. Here species peel off slowly. I will list them in the order that they split.

The first split is the minke whale – of which there are 2 species, the common and southern minke whale, with the grey whale being the next most similar.

Brydes whale
Antarctic (Southern) Minke Whale
Grey whale
Common minke whale
Sei whale mother and calf Christin Khan NOAA

The next are the humpback whale and the fin whale followed by the Blue whale.

Underwater humpback whale jd forester
fin whale by Amila Tennakoon
Blue whale, taken by Australian Antarctic program

The last group of whales are from a group called the Brydes whales complex

Brydes whale
Edens whale
Omuras whale
Rice whale
Sei whale mother and calf Christin Khan NOAA

This completes the list of baleen whales. The other branch of the Cetaceans is known as the toothed whales

Toothed Whale

.I am going to look at them in 3 groups, though the third is not particularly closely related to each other

  • Delphinoidea: This includes
    • Monodontidaes – Belugas and narwhals
    • Phocoenidae – The family of Porpoises (7 species) such as harbour porpoises and Vanquita

 

bermeister porpoises
dalls porpoise Susan E Adams
Harbour Porpoise
Indo pacific (or east Asian) finless porpoise
Spectacled porpoise
Vaquita (Paula Olson NOAA)
Narrow Ridged finless porpoise (Yangtze finless porpoise by huangdan2060)
    • Delphininidae – these are the oceanic dolphins – 37 species split into several subfamilies which we will deal with one by one.
Subfamily Delphininae – 15 species (tamanend bottle nose dolphin only recognized as separate species, will build page for it at some point when photos are readily available.

Subfamily  Globcephalinae 11 species

Australian snubfin dolphin
False killerwhale by Adam U
Long-finned pilot whale nu Gailhampshire
Rough toothed dolphin
Melon-headed Dolphin by Cyril di Bisceglie
Pygmy killer whales (Feresa attenuata) off of Guam
Irrawaddy Dophin
Short-finned pilot whale by Martina Nolte
Risso’s dolphin

Subfamily incerta sedis (latin for “of uncertain placement” )6 species

Atlantic White-sided Dolphin
Dusky dolphin by AllenMoC
Hourglass dolphin by Lomvi2
Pacific white sided dolphin by NMFS southwest fisheries science center
Peales dolphin by fDrummondH
White beaked dolphin

Subfamily Lissodelphininae 6 sppecies

Black dolphins by Bobbyandck
Commerson's dolphin by Tonina1
Haviside dolphin by Joachim Huber
Hector dolphin by Avenue
Northern right whale dolphin
Southern right whale dolphin

Subfamily Orcininae

Orca by Robert Pittman NOAA
  • Inioidea : This includes 3 groups
    • Iniidae (only 1 of 5 genus remains -Inea (4 species: Araguaian river dolphin, Bolivian river dolphin  and Orinoco dolphin)
Amazon river dolphin by Oceancetaceen sometimes known as the Orinoco
Araguaian river dolphin by Rio Cicica
Bolivian river dolphin by Ramon and Suzanne Vargas
    • Lipotidae: which contains only one species: the Baiji or Chinese river dolphin
  • Pontoporiidae: which contains one species 
La plata dolpin

The next family is the beaked whales. There are 24 species, of which only 3-4 have been well studied. This is because they spend much of their time deep in the sea, it appears that each species does not have many members and they are incredibly reclusive in their habits.

One might ask how an air breathing animal can spend so much of its time deep in the ocean? Well the Curved beaked whale has had a dive timed at 138 minutes. More incredible, they only need around 2 minutes to catch their breathe before sinking back into the depths. This means that if required, they can spend just 20 minutes out of 24 hours at the surface – an incredible stunt.

There appear to be a great number of species that are extinct – these we will not list, but will mention each subfamily in passing.

Incertae sedis contains 5 extinct genus, Basal forms include 13 extinct genus

Subfamily Berardiinae contains 3 genus, 2 of which are extinct, but the third contains 3 living species (and one dead) .  

Genus Beradius

 

Arnoux's beaked whale
Baird beaked whale
Sato beaked whale

Next we cover the Bottlenose whales

Northern                                                                                                                     Southern and                                                        Tropical

northern bottlenose whale
Southern bottlenose whale
Tropical bottlenose whale

Subfamily Ziphiinae  contains 5 genus, 3 are extinct, but two have just one species in each

Genus Tasmacetus: Shepherds beaked whale Genus Ziphius: Cuviers beaked whale

Click on the image to see it in full

The most populous genus Mesoplodon – mesoplodont whales

As you can see, many of the pictures are of dead whales, or skulls or diagrams, or even just text. This is because sightings of many species are so rare that they have never had a photo taken

As you can see from the whale family tree, the sperm whales are separate from the rest. However, they are toothed whales so belong in this section of the page.

pygmy sperm whale
Sperm-whale-by-Gabriel-Barathieu
See Animals Wild