Tag: Blue whale

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New DNA tests have found that blue whales have been mating with fin whales

It appears that blue whales have been mating with fin whales far more frequently than previously thought. One of the things that is both exciting and alarming, is that it suggests that whales can interbreed more easily.

While they are currently listed as endangered, and are starting to recover, of the 4 subspecies, the one found in the north Atlantic and the north Pacific is the most at risk. In otherwards, this subspecies could become extinct as a result of hybridisation.

On average around 3.5% of the blue whale DNA, comes from the fin whale.

It is perhaps odd that these species would interbreed, as blue whales weigh around 85 tonnes more than fin whales.

It had been assumed that these occasional hybrids could not go on to produce fertile offspring, but this has been shown to not be the case. What appears interesting though, is that there does not appear to be any blue whale DNA in the fin whale population, suggesting that they offspring will only ever be able to breed with blue whales.

Fin Whale

Fin Whale

The fin whale which is also known as finback whale or common rorqual and formerly known as herring whale or razorback whale, is the second longest species of whale, with the largest species growing to a reported 27m, and weighing a maximum recorded weight of 74 tonnes, and a maximum estimated weight of 114 tonnes.

It is a fast swimmer, able to outpace the fastest steamships.

There are 2 recognized subspecies, in the northern and southern hemisphere. Around 725,000 southern fin whales were taken during whaling, and there are around 38,000 that roam the oceans as of 1997. Across the world around 112,000 roam the oceans.

Although the genetic differences between the fin whale and the blue whale are considered similar to that of humans and gorillas (they are thought to have been split for 3.5 million years) and hybrids have been recorded from time to time.

Average dives are around 6 minutes, with the longest dives recorded being around 17 minutes.

Found around the world, though not found close to the polar ice caps at either end of the globe. They appear to be clearly migratory, but it has not been possible to fully work out what this migration pattern might be.

 

 

Blue Whale

Blue whale

The largest species of whale, the largest species of mammal, indeed at almost 30m the largest species ever known to live on earth, they can weigh up to 200 tonnes. There are 4 subspecies with a possible 5 in contention.

Abundant in almost all of the worlds oceans until the 19th century, they were hunted close to extinction. In 1966 hunting of them were banned.

There are places around the world, where these animals can be watched, we hope to link to many of these below.

At their peak, before whaling, it was thought that their was around 350,000 in the world. Now there is between 10,000 and 25,000 around the world.

It is certainly not the time to allow them to be hunted again, far from it.

One recent suggestion, is that whales sink huge quantities of carbon down into the ocean, and that our current problems with global warming might have been tiny if we had not killed the vast majority of most species of Baleen whales.

Below is a small outtake from blue planet, the bbc series from 2001 which features a blue whale in the vastness of the ocean

I have included a second video clip, as this one give you an idea of the size and shape of a blue whale, in a way that little footage does.

Below this is any articles that have been written about blue whales on this website, and below that, we will add any links that might help you see blue whales in the wild.

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
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Orca have been documented killing and eating blue whales

Orca are generally regarded as the apex predator in the sea. There are obviously others that are good contenders, such as the great white shark – but when orca are nearby, great white sharks go very quiet in an attempt to not draw attention.

It would seem that nothing is too big to be food. Coordinated female lead pods of orca have been documented ramming the whale, and then eating its tongue before it dies.

It is, I suppose, not something that should be remotely surprising. Orca have developed ways of feeding on all sorts of food that would at first glance be out of reach. From rushing in towards a beach, allowing them to aquaplane up onto the beach to grab sea lions, to stunning fish with their tale – stopping them darting away, there is a fascinating range of hunting techniques that they employ.

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Previously unknown group of blue whales found

Given how large they are, you would have thought that we would know about all populations of the blue whale, but it would appear not.

A new population has been found living in the Indian ocean. It was discovered, when a researcher off the coast of Madagascar, recorded their song, and it did not match any of the known songs.

A blue whale in the Indian ocean
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