# Next biggest "non-whale" sea creature after the blue whale? **URL:** \ **Category:** Factual Questions\ **Created:** [February 21, 2012, 1:51pm UTC](https://boards.straightdope.com/t/next-biggest-non-whale-sea-creature-after-the-blue-whale/613524 "2012-02-21T13:51:17Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![gytalf2000](https://avatars.discourse-cdn.com/v4/letter/g/ac91a4/32.png) [@gytalf2000](https://boards.straightdope.com/u/gytalf2000)\ **Post date:** [February 21, 2012, 1:51pm UTC](https://boards.straightdope.com/t/next-biggest-non-whale-sea-creature-after-the-blue-whale/613524/1 "2012-02-21T13:51:17Z")
We all know that the blue whale is the biggest animal that has ever lived (at least, no bigger animal in the fossil record has yet been found). A few of the gigantic sauropod dinosaurs may have been longer, but could not match the blue whale’s massive bulk. Of course, they were land dwellers, and actually had to support their own weight, so this is really an “apples and oranges” type of comparison… My question is – what sea creature (that isn’t another whale) came the closest to the blue whale in length and/or bulk? I’m asking for current examples and also creatures from the fossil record. Any information would be appreciated. Thanks! ---
**Author:** ![jjimm](https://avatars.discourse-cdn.com/v4/letter/j/ba8739/32.png) [@jjimm](https://boards.straightdope.com/u/jjimm)\ **Post date:** [February 21, 2012, 1:53pm UTC](https://boards.straightdope.com/t/next-biggest-non-whale-sea-creature-after-the-blue-whale/613524/2 "2012-02-21T13:53:42Z")
Current: whale shark. ---
**Author:** ![Meurglys](https://avatars.discourse-cdn.com/v4/letter/m/258eb7/32.png) [@Meurglys](https://boards.straightdope.com/u/Meurglys)\ **Post date:** [February 21, 2012, 2:03pm UTC](https://boards.straightdope.com/t/next-biggest-non-whale-sea-creature-after-the-blue-whale/613524/3 "2012-02-21T14:03:56Z")
This Cretaceous period [mosasaur](http://www.bbc.co.uk/science/seamonsters/factfiles/giantmosasaur.shtml?img1) could reach over 50 feet in length and weigh up to 20 tonnes apparently. ---
**Author:** ![njtt](https://avatars.discourse-cdn.com/v4/letter/n/ecd19e/32.png) [@njtt](https://boards.straightdope.com/u/njtt)\ **Post date:** [February 21, 2012, 2:06pm UTC](https://boards.straightdope.com/t/next-biggest-non-whale-sea-creature-after-the-blue-whale/613524/4 "2012-02-21T14:06:01Z")
The [colossal squid](http://en.wikipedia.org/wiki/Colossal_squid) probably gets longer than the whale shark. Not so heavy, though, I don’t suppose. ---
**Author:** ![jjimm](https://avatars.discourse-cdn.com/v4/letter/j/ba8739/32.png) [@jjimm](https://boards.straightdope.com/u/jjimm)\ **Post date:** [February 21, 2012, 2:12pm UTC](https://boards.straightdope.com/t/next-biggest-non-whale-sea-creature-after-the-blue-whale/613524/5 "2012-02-21T14:12:11Z")
> [@Meurglys](#): > > This Cretaceous period [mosasaur](http://www.bbc.co.uk/science/seamonsters/factfiles/giantmosasaur.shtml?img1) could reach over 50 feet in length and weigh up to 20 tonnes apparently. Pah. I see your mossy sore and raise you a _land_ animal, the [amphicoelias fragillimus](http://en.wikipedia.org/wiki/Amphicoelias_fragillimus), which may have weighed 122 tonnes and may have been 60 metres (200 feet) long. Unfortunately the fossils have been lost. Quite how someone can lose the fossils of the largest land animal ever to have lived I don’t know - probably fallen down the back of the sofa or something. ETA: I was off topic I realise. I just got excited in a Ross Geller kind of way. Sorry, OP. More here: [Largest prehistoric organisms](http://en.wikipedia.org/wiki/Largest_prehistoric_organisms) at Wikipedia. ---
**Author:** ![Sailboat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sailboat/32/461_2.png) [@Sailboat](https://boards.straightdope.com/u/Sailboat)\ **Post date:** [February 21, 2012, 2:14pm UTC](https://boards.straightdope.com/t/next-biggest-non-whale-sea-creature-after-the-blue-whale/613524/6 "2012-02-21T14:14:56Z")
Agree the [Whale Shark](http://en.wikipedia.org/wiki/Whale_shark) is probably the most massive living sea creature aside from whales – one specimen reached 35.8 tonnes. For length, I’ll nominate the [Colossal Squid](http://en.wikipedia.org/wiki/Colossal_squid). Although much lighter in mass, current estimates put its maximum size at 12–14 meters (39–46 ft) long. For extinct animals, I’d nominate the various species of [Mosasuars](http://en.wikipedia.org/wiki/Mosasaur). The largest yet found, Hainosaurus, measured 17.5 meters (57 ft). A different extinct animal group, the [Pliosaurs](http://en.wikipedia.org/wiki/Pliosaur), was typically substantially shorter in length, but a couple of new specimens have been tentatively estimated at 49 and 52 feet in length. Since Pliosaurs tended to have more massive bodies than the snake-like Mosasaurs, that might make them candidates. D’oh – took too long typing, I see. ---
**Author:** ![Polycarp](https://avatars.discourse-cdn.com/v4/letter/p/82dd89/32.png) [@Polycarp](https://boards.straightdope.com/u/Polycarp)\ **Post date:** [February 21, 2012, 3:13pm UTC](https://boards.straightdope.com/t/next-biggest-non-whale-sea-creature-after-the-blue-whale/613524/7 "2012-02-21T15:13:50Z")
> [@jjimm](#): > > Pah. I see your mossy sore and raise you a _land_ animal, the [amphicoelias fragillimus](http://en.wikipedia.org/wiki/Amphicoelias_fragillimus), which may have weighed 122 tonnes and may have been 60 metres (200 feet) long. Unfortunately the fossils have been lost. Quite how someone can lose the fossils of the largest land animal ever to have lived I don’t know - probably fallen down the back of the sofa or something. ETA: I was off topic I realise. I just got excited in a Ross Geller kind of way. Sorry, OP. > > More here: [Largest prehistoric organisms](http://en.wikipedia.org/wiki/Largest_prehistoric_organisms) at Wikipedia. Apparently, it crumbled. There were two bones, one of which was a back vertebra. They were preserved in a crumbly mudstone, and the significance, in a time when new bigger dinosaurs were discovered seemingly every moth, was not realized at the time. ---
**Author:** ![Grendel\_s\_Father](https://avatars.discourse-cdn.com/v4/letter/g/b782af/32.png) [@Grendel\_s\_Father](https://boards.straightdope.com/u/Grendel_s_Father)\ **Post date:** [February 21, 2012, 4:25pm UTC](https://boards.straightdope.com/t/next-biggest-non-whale-sea-creature-after-the-blue-whale/613524/8 "2012-02-21T16:25:50Z")
A few notable giant prehistoric sea creatures not mentioned already include the fish \*[Leedsichthys problematicus](http://en.wikipedia.org/wiki/Leedsichthys) \* and a few giant ichthyosaurs _[Shastasaurus sikanniensis](http://en.wikipedia.org/wiki/Shastasaurus)_ and _[Shonisaurus popularis](http://en.wikipedia.org/wiki/Shonisaurus)_ (the latter hilariously proposed to have had their vertebrae torn apart and arranged into self-portraits by an [enormous cephalopod](http://www.wired.com/wiredscience/2011/10/the-giant-prehistoric-squid-that-ate-common-sense/)). ---
**Author:** ![heathen\_earthling](https://avatars.discourse-cdn.com/v4/letter/h/13edae/32.png) [@heathen\_earthling](https://boards.straightdope.com/u/heathen_earthling)\ **Post date:** [February 21, 2012, 4:32pm UTC](https://boards.straightdope.com/t/next-biggest-non-whale-sea-creature-after-the-blue-whale/613524/9 "2012-02-21T16:32:14Z")
> [@Polycarp](#): > > Apparently, it crumbled. There were two bones, one of which was a back vertebra. They were preserved in a crumbly mudstone, and the significance, in a time when new bigger dinosaurs were discovered seemingly every moth, was not realized at the time. If there was a second bone besides the giant dorsal vert, Cope didn’t mention or figure it in his description. Where did you hear about it? ---
**Author:** ![Grendel\_s\_Father](https://avatars.discourse-cdn.com/v4/letter/g/b782af/32.png) [@Grendel\_s\_Father](https://boards.straightdope.com/u/Grendel_s_Father)\ **Post date:** [February 21, 2012, 4:35pm UTC](https://boards.straightdope.com/t/next-biggest-non-whale-sea-creature-after-the-blue-whale/613524/10 "2012-02-21T16:35:47Z")
> [@heathen\_earthling](#): > > If there was a second bone besides the giant dorsal vert, Cope didn’t mention or figure it in his description. Where did you hear about it? It was mentioned in the recovered field notes of the collecting team, IIRC. Cope seems not to have received the specimen (probably crumbled during transport). It was a distal femur collected near the vertebra. Mentioned in Carpenter’s 2006 paper “Biggest of the big: a critical re-evaluation of the mega-sauropod _Amphicoelias fragillimus_.” ETA: Actually the femur is figured here: [File:Amphicoelias bones1.jpg - Wikipedia](http://en.wikipedia.org/wiki/File:Amphicoelias_bones1.jpg) Don’t know if that’s an original drawing, scale-up from _A. altus_, or what… ---
**Author:** ![DrDeth](https://avatars.discourse-cdn.com/v4/letter/d/b487fb/32.png) [@DrDeth](https://boards.straightdope.com/u/DrDeth)\ **Post date:** [February 21, 2012, 6:09pm UTC](https://boards.straightdope.com/t/next-biggest-non-whale-sea-creature-after-the-blue-whale/613524/11 "2012-02-21T18:09:23Z")
It’s the Megalodon, which at up to 100 tonnes, was in there with the whales and the largest “fish” ever to swim the seas. > **[Megalodon](https://en.wikipedia.org/wiki/Megalodon#Body_mass_estimates)** > > Megalodon (/ˈmɛɡələdɒn/ MEG-əl-ə-don; Otodus megalodon), meaning "big tooth", is an extinct species of mackerel shark that lived approximately 23 to 3.6 million years ago (Mya), from the Early Miocene to the Pliocene epochs. It was formerly thought to be a member of the family Lamnidae and a close relative of the great white shark (Carcharodon carcharias). However, it is now classified into the extinct family Otodontidae, which diverged from the great white shark during the Early Cretaceous.... ---
**Author:** ![gytalf2000](https://avatars.discourse-cdn.com/v4/letter/g/ac91a4/32.png) [@gytalf2000](https://boards.straightdope.com/u/gytalf2000)\ **Post date:** [February 21, 2012, 8:32pm UTC](https://boards.straightdope.com/t/next-biggest-non-whale-sea-creature-after-the-blue-whale/613524/12 "2012-02-21T20:32:35Z")
Fascinating info! Thanks for the replies. ---
**Author:** ![Sailboat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sailboat/32/461_2.png) [@Sailboat](https://boards.straightdope.com/u/Sailboat)\ **Post date:** [February 21, 2012, 8:53pm UTC](https://boards.straightdope.com/t/next-biggest-non-whale-sea-creature-after-the-blue-whale/613524/13 "2012-02-21T20:53:57Z")
> [@DrDeth](#): > > It’s the Megalodon, which at up to 100 tonnes, was in there with the whales and the largest “fish” ever to swim the seas. > > [Megalodon - Wikipedia](http://en.wikipedia.org/wiki/Megalodon#Body_mass_estimates) That article seems to settle on 50-55 feet for size estimates. Unless I skimmed too fast, the 103-tonne figure appears to be for a hypothetical 67-foot size not mentioned in the paragraphs discussing best size estimates. ---
**Author:** ![Otara](https://avatars.discourse-cdn.com/v4/letter/o/a88e4f/32.png) [@Otara](https://boards.straightdope.com/u/Otara)\ **Post date:** [February 21, 2012, 9:24pm UTC](https://boards.straightdope.com/t/next-biggest-non-whale-sea-creature-after-the-blue-whale/613524/14 "2012-02-21T21:24:57Z")
> **[Lion's mane jellyfish](https://en.wikipedia.org/wiki/Lion's_mane_jellyfish)** > > The lion's mane jellyfish (Cyanea capillata), also known as the giant jellyfish, arctic red jellyfish, or the hair jelly, is one of the largest known species of jellyfish. Its range is confined to cold, boreal waters of the Arctic, northern Atlantic, and northern Pacific Oceans. It is common in the English Channel, Irish Sea, North Sea, and in western Scandinavian waters south to Kattegat and Øresund. It may also drift into the southwestern part of the Baltic Sea (where it cannot breed due to ... Cheating perhaps? Can be longer than a blue whale. Otara ---
**Author:** ![DrDeth](https://avatars.discourse-cdn.com/v4/letter/d/b487fb/32.png) [@DrDeth](https://boards.straightdope.com/u/DrDeth)\ **Post date:** [February 21, 2012, 9:40pm UTC](https://boards.straightdope.com/t/next-biggest-non-whale-sea-creature-after-the-blue-whale/613524/15 "2012-02-21T21:40:58Z")
> [@Sailboat](#): > > That article seems to settle on 50-55 feet for size estimates. Unless I skimmed too fast, the 103-tonne figure appears to be for a hypothetical 67-foot size not mentioned in the paragraphs discussing best size estimates. Still bigger than the whale shark, however. ---
**Author:** ![gytalf2000](https://avatars.discourse-cdn.com/v4/letter/g/ac91a4/32.png) [@gytalf2000](https://boards.straightdope.com/u/gytalf2000)\ **Post date:** [February 21, 2012, 10:33pm UTC](https://boards.straightdope.com/t/next-biggest-non-whale-sea-creature-after-the-blue-whale/613524/16 "2012-02-21T22:33:02Z")
> [@Otara](#): > > [Lion's mane jellyfish - Wikipedia](http://en.wikipedia.org/wiki/Lion's_mane_jellyfish) > > Cheating perhaps? Can be longer than a blue whale. > > Otara I was aware that there was a jellyfish with tentacles longer than a blue whale, but I couldn’t remember which species it was. Thanks for the link! And I know that I said “sea creature” in the original post, but I really meant “vertebrates of substantial mass”. I didn’t specify that, though, so the Lion’s mane jellyfish deserves a mention! ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [February 21, 2012, 11:03pm UTC](https://boards.straightdope.com/t/next-biggest-non-whale-sea-creature-after-the-blue-whale/613524/17 "2012-02-21T23:03:02Z")
> [@](#): > > And I know that I said “sea creature” in the original post, but I really meant “vertebrates of substantial mass”. A very significant clarification, given that the giant squid is one of the contenders. ---
**Author:** ![cjepson](https://avatars.discourse-cdn.com/v4/letter/c/a9adbd/32.png) [@cjepson](https://boards.straightdope.com/u/cjepson)\ **Post date:** [February 22, 2012, 4:30pm UTC](https://boards.straightdope.com/t/next-biggest-non-whale-sea-creature-after-the-blue-whale/613524/18 "2012-02-22T16:30:27Z")
OK, this doesn’t count for a variety of reasons, but I decided to post it anyway because I thought people might be interested. It’s video of a [giant pyrosome,](http://www.youtube.com/watch?v=5EQGA_4BZ5s)which is actually a colony of thousands of small organisms. ---
**Author:** ![Sailboat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sailboat/32/461_2.png) [@Sailboat](https://boards.straightdope.com/u/Sailboat)\ **Post date:** [February 22, 2012, 5:10pm UTC](https://boards.straightdope.com/t/next-biggest-non-whale-sea-creature-after-the-blue-whale/613524/19 "2012-02-22T17:10:30Z")
> [@cjepson](#): > > OK, this doesn’t count for a variety of reasons, but I decided to post it anyway because I thought people might be interested. It’s video of a [giant pyrosome,](http://www.youtube.com/watch?v=5EQGA_4BZ5s)which is actually a colony of thousands of small organisms. While looking this up on Wikipedia, I was startled to learn that these things are _chordates_. It’s something of an oversimplification, but, despite their looks, pyrosomes are more closely related to humans than to jellyfish (Cnidaria)! ---
**Author:** ![Mahaloth](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mahaloth/32/1079_2.png) [@Mahaloth](https://boards.straightdope.com/u/Mahaloth)\ **Post date:** [February 22, 2012, 5:34pm UTC](https://boards.straightdope.com/t/next-biggest-non-whale-sea-creature-after-the-blue-whale/613524/20 "2012-02-22T17:34:08Z")
I came in to say Whale Shark as well, one of my favorite creatures in all existence. A shark so large is basically dwarfs all other sharks. A beautiful creature and I believe that despite its size, it does not even chow down on meat the way other sharks do. I think it just continually filters food through its mouth [Here is a 45 ft one.](http://www.youtube.com/watch?v=UMJMi88MfjI) [Next page](https://boards.straightdope.com/t/next-biggest-non-whale-sea-creature-after-the-blue-whale/613524.md?page=2)