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Post by creature386 on Oct 6, 2014 0:13:44 GMT 5
I admit that I repeated a lot, but I at least brought up some new material. Oh, and for the ones who are interested in support for my "this may explain why groups for smaller prey are larger than the ones for large prey" statement:  This is strange since the most famous account of attak on a blue whale involved 29 orcas individuals. I know this, I was more using it as evidence for the pods being larger when it comes to medium sized prey. Don't get irritated by the fact that I highlighted some words, this is because I used it in a different debate before. 7.hidemyass.com/ip-1/encoded/Oi8vY2Fybml2b3JhZm9ydW0uY29tL3RvcGljLzk2MDIwNzIvMTM%3D&f=norefer(I hope the proxy server makes it available to you) |
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Post by theropod on Oct 6, 2014 0:36:11 GMT 5
Fair enough then. I’ve never said that there is no overlap, it looked as if you were trying to say that orcas individually are comparable to great whites in terms of prey selection. Now you are misinterpreting what I wrote: While I consider the relying on "common knowledge" a bad habit in science, this has indeed been reported, I don’t deny that. Namely, this article: www.sharkresearchcommittee.com/predation.htm But note that these are once again northern elephant seals. That’s quite a difference in terms of size. Yes, that would be greatly appreciated. False killer whales are also relatively scarce: No estimates of worldwide population size are available, although false killer whales appear to be naturally uncommon throughout their range. Also false killer whales are poorly studied (which is far more important because it directly affects what gets documented), this seems to be noted in many of the research works I’ve come across (and obviously as a species they attract far less attention than great white sharks do), in stark contrast to great white sharks, further complicated by their pelagic habits, and indirect indications of attacks on larger prey may be confused with those of orcas (for example mentioned in Palacios & Mate 1996→). So that there is so much less research on false killer whales than there is on Great whites, and that their bite makrs can be easily confused with those of orcas certainly contributes to fewer predatory encounters being described. No, great whites also don’t regularly target large prey. the vast majority of prey they take is smaller pinnipeds. The first one is right (fish comparable to a lot of great white shark prey in size though). The second half of your sentence makes it sound like you know such accounts. It would be greatly appreciated if you could post them, and also explain how feats achieved in a group are not relevant to an animal’s trophic status. Producing the whole paper or at least giving others the chance to do it is important, it allows them to at least look up the references instead of having to blindly rely on a claim that is made. that’s debatable. Killer whales are able to exploit a food source (large baleen whales) that is completely inaccessible to either great whites or FKWs. Both of the latter at most take whale calves. |
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stomatopod
Junior Member
Gluttonous Auchenipterid
Posts: 182
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Post by stomatopod on Oct 6, 2014 0:39:21 GMT 5
Elosha,
There has been considerable progress on the taxonomy of the genus Orcinus in the last years. But splitting it into different species will be a magnum opus.
Here are some reasons:
- It has to be analysed which population is referred to in the origal description of O. orca. Most likely it refers to European fish hunting population. Alternatively it is a combination of European fish and whale hunters.
-A neotype needs to be proposed.
-We have to look of one of the current synonyms of O. orca refers to one of the New species.
-Some type specimens of those "Synonyms" are lost or never declared. Of the holotype of O. glacialis had not been destroyed of would most likely valid by now.
-We still need much more data on genetics to avoid para and polyphylies. And we need autosomal DNA
From what I have gathered and remember from prior conversations there will be at least 4 species:
A primarily whale rating species comprimising of Type A, European whale hunters(this clade has already been found to real) and most likely transients.
A species containing B and C types, though those could be up to three closely related species.
The C type most likely is a species on its own.
And them there is what might be your bread and butter orca, which could contain residents, off-shores and Northern Atlantic fish eaters. Again, might be more than one species.
I think this could take a few more years entangle.(Though if I would have a degree in biology I would write a quick paper about that matter and create those 4 species and them later clean up. For conservation purposes this might be essential.)
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Post by theropod on Oct 6, 2014 0:43:03 GMT 5
 If that was so easy. Taxa have been proposed in works of hundreds of pages, and yet are considered nomina dubia. |
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Post by Grey on Oct 6, 2014 1:11:35 GMT 5
What ? Could you be more clear ?
Cousteau books, various accounts of captured sharks...That's no extraordinary claim.
More regular than Pseudorca biggest preys. Individually, GWS target larger preys items, more often.
Flesh grazing is not exactly predation, more parasitism, it implies no killing.
Common enough for that random guys on boat caught it on cam. Probably more common than O. orca preying individually against an adult Megaptera...
I had already used this quote earlier and posted the references, I didn't know you'd need it again. Now, you should try to relax yourself.
Okay, so please give us an actual modern account of an individual orca engaging and killing prey several orders of magnitude larger.
Well, I'm not the one favoring a 140 years old account over modern scientific statements (i.e : that Pseudorca operates at lower trophic systems than Carcharodon/than it mostly preys on squids and fishes so is usually a lesser big game hunter than GWS).
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Post by theropod on Oct 6, 2014 2:10:26 GMT 5
what exactly was not clear enough?
Again, you are making a claim without bringing evidence!
Favouring what over what? These are two completely different things (one is a concrete albeit dated observation, the other a generalized claim on ecology), related to different animals (Orcinus orca as compared to C. carcharias and P. crassidens), relevant to two completely different subjects (maximum individual prey size of one animal vs alledged trophic relationship between two other animals)!
I don’t even doubt that Pseudorca typically targets smaller prey (mostly the cephalopod part), at least in some regions, as I wrote that’s related to their respective habitats, but it still shows prominent adaptions for hunting big prey, and a large part of its prey range overlaps with Carcharodon perfectly in terms of size composition.
If you can compile data (or find a study that does so), that demonstrates large prey is more rarely trageted by False killer whales than by great white sharks, or find evidence for the shark dominating in direct competition/confrontation, then we can talk*…
are you using binary numbers? Otherwise a humpback whale isn’t "several orders of magnitude" larger than a killer whale. Can you give me any account at all of an individual great white shark engaging and killing prey several orders of magnitude larger?
If not, then I think the situation is pretty clear: The killer whale takes larger prey than a great white shark, both individually and in groups, in perfect accordance with its larger size.
It’s more akin to predation if it involves attacking something.
That’s not the question, of course a solitary shark killing a dolphin at best subequal to itself in size is far more common than a typically pod-hunting orca killing a baleen whales a few times its own size on its own.
As commonly as the much larger, social and more macrophagous Pseudorca crassidens attacks dolphins? The latter taking dolphins is never once doubted in any paper I’ve read on it.
*See what I did there?
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Post by Grey on Oct 6, 2014 3:02:59 GMT 5
All your statement. I ask you to bring evidences too, that FKW kills big games as commonly as the GWS does. I ask you to bring evidence that Compagno claims are bullshits. www.nmfs.noaa.gov/pr/species/mammals/cetaceans/falsekillerwhale.htmDiet: fishes and cephalopodsThey feed during the day and at night on fishes and cephalopods, and they are known to attack smaller dolphins that are involved in the tuna purse-seine fishery in the Pacific Ocean.www.sci.tamucc.edu/tmmsn/29Species/falsekillerwhale.htmlDiet: Squid or octopus, fish, and occasionally mammalsseamap.env.duke.edu/species/180463/htmlFalse killer whales have a broad diet characterized by: Squid > fish. Although false killer whales eat primarily fish and cephalopods, they also have been known to attack small cetaceans and, on one occasion, even a humpback whale. They feed by seizing their prey.
Known prey species include:
Fish: Oncorhynchus sp., Sarda sp., Coryphaena sp., Thunnus albacares, Psuedosciana sp., Lateolabrax japonicus, Seriola lalandi, Tachysurus spp., Macruronus magellanicus, Micropogonias furnieri, Pogonias cromis, Genypterus blacodes
Invertebrates: Ommastrephes bartramii, Martialia hyadesi, Illex argentinus, Todarodes filippovae, Ocythoe sp., Moroteuthis ingens, Teuthowenia megalops, Octopoteuthis sp., Gonatus antarcticus, Mastigoteuthis sp., Lycoteuthis cf. diadema, Thysanoteuthis rhombus, Todarodes angolensis, Loligo v. reynaudii
STOMACH CONTENTS OF FALSE KILLER WHALES (PSEUDORCA CRASSIDENS) STRANDED ON THE COASTS OF THE STRAIT OF MAGELLAN, TIERRA DEL FUEGO We examined the stomachs of 25 false killer whales collected from a mass stranding of 181 animals along both coasts of the Strait of Magellan, Chile, in March 1989. The 21 stomachs (nine males and 12 females), with food remains contained 11 prey species (nine cephalopods and two fishes) with a total of 442 individuals. Except for one case, food remains were meager, indicating that the animals had not eaten for some time or through stress had vomited on the beach. Eleven of the 21 animals had mud (often with squid beaks) in the esophagus and first stomach. The prey were identified employing squid beaks, fish otoliths and bones, and their wet weights were estimated using regressions between hard parts and known weights of species. The most important prey were the oceanic and neritic-oceanic squids, Martialia byadesi and Illex argentinus, followed by the neritic fish, Macruronus magellanicus. Of less importance were the oceanic squid, Todaroes fillipovae, the oceanic and epipelagic octopus, Ocytboe sp., and the oceanic squid, Moroteuthis ingens. The rest of the prey were poorly represented and included four oceanic squids and one neritic fish. The prey species of these animals were subantarctic, with two antarctic species, abundant over the Patagonian shelf and adjacent oceanic waters around Tierra del Fuego.
No mammalian, cetacean, large-sized preys items in the stomach of these 25 individualsFKW mostly does not operate at the same trophic systems than GWS.
I highly question the reliability of an observation dating back 140 years old never documented again since whereas you use it as a solid data. But you try to challenge the claims of Compagno which are based on actual statements : Pseudorca typically targets smaller prey items than Carcharodon, hence operating at lower trophic systems. I point on your difference of treatment between one very old, strangely not documented since observation and a modern scientific claim. Pseudorca lives in the regions where it is most likely going to find its adequate preys items since the habitat is determined too by the feeding habits. The great white is a coastel predator because its preys are coastal. Yes FKW can hunt big preys, but that's more occasionnal than GWS. GWS big pinnipeds preys items overlaps with Orcinus, not with Pseudorca. An orca weighs 5-8 tonnes, a Megaptera weighs over 30 tons... My mistake, I meant one order of magnitude above, no need to use that mistake of mine to try to disqualify my post. That's all your evidence for claiming that orcas can prey and kill individually large baleen whales ? An account 140 years old that is not reported anywhere else and has never been documented since ? If you find a more recent case where an orca has attacked and killed a much larger prey than itself, then we can discuss, I'd be very interested if that's true and documented. The only case I've ever heard about from a sole orca attacking a much larger foe was from a french orca fangirl : allegedly, an individual had been spotted biting a large right whale, being dragged by the colossal animal on severals tens of yards before letting the prey escape. Never seen that case reported elsewhere. But I'd give certainly more credential than this old account of an orca killing by itself a large humpback. To be fair, I'm surprised that you take this account like if it was written in the stone and that you so fastly make a day "O. orca can kill much larger preys than GWS individually". You're questionning recent, documented, scientific cases of GWS plausibly attacking FKW but you use totally unverifiable old accounts, never seen again events to try to make your point correct. I really thought you had improved your objectivity in the treatment of information and research, it appears that's not yet the case. So instead of asking me evidences for my claims, which I've done, I ask you evidences and documented cases : - where it is demonstrated that O. orca individually kills much larger preys items. - where P. crassidens kills on a regular basis warm-blooded mammals comparable to sea lions in body mass, as much as adults GWS do. Actually I've clearly proven that Compagno's claim is accurate with the various sources above. |
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Post by theropod on Oct 6, 2014 16:31:12 GMT 5
That two animals have been known to overlap on a specific prey item doesn't mean they are on the same trophic level. African wild dogs, cheetahs and lions have all been recorded to prey on wildebeest, but that doesn't mean one of these could not prey on the others. But if two animals have largely overlapping prey, similar body size, and especially, perfectly comparable maximum prey size (i.e. predatory capabilities), that indicates something about their ecology which you cannot simply brush aside. There are populations of orcas almost exclusively feeding on fish, and many populations (as you correctly remarked), overlap great white sharks in parts of their diet (small-midsized pinnipeds), and yet it is not rocket science to determine which one is higher in the trophic systems–it’s the one that also kills large whales, the one that is far larger and that is presumed to displace, and occasionally prey upon, great whites themselves. Point on that as long as you want, it changes nothing. An observation of a specific event is a completely different thing from a generalized claim on an animal's ecology. The sources that Compagno gives (which I'm sure you haven't checked either) predate every single source on Pseudorca ecology posted in this thread so far (that includes the attack on sperm whales and also the source cited for the case of the humpback whale-calf), which actually makes them much more prone to being outdated. You shouldn't complain about the age of the account. An observation on the other hand doesn't get invalid just because of its age. Of course people like to hide between accusations of unreliable reporting, but lots of the sources cited here are far worse in that regard (everyone's favourite "evidence" of sharks supposedly killing FKWs for example). Why would you say is it that works by Owen, Marsh, Cope, Osborn etc. (or in this case, Eschricht) are still cited in the scientific literature, no matter how dated (and on many matters, outdated) they are? Because scientists are so biased as to accept works by scientists that lived a century ago? And then, what exactly do you find so difficult to believe about it? Many extant predators are known to kill prey items several times their size on their own (Wolf-Bison, Tiger-Gaur, Lion-Buffalo, Aquila-Caribou, Cougar-Horse). This is uncommon, but not extremely rare either, and its ocurrence in the world's apex macropredator shouldn's surprise you that much. What's actually rather odd is that this is has not been reported for great white sharks (correct me if I'm wrong) so far, because one would expect it to happen. Even more, what the hell is so difficult to swallow about Orcinus orca being able to kill larger prey individually than C. carcharias? Orcinus orca is roughly three times the size, it would be expected to be capable of doing that! You are acting as if that was an extraordinary claim that required extraordinary evidence, when it fact it is the default assumption! Why don't you come up with evidence that this is not the case? After all, what you demand from me is to bring up evidence that Carcharodon and Pseudorca have a similar torphic level, even though these two are actually similar in size and the prey they can take is similar too! And by the way, that account is "reported somewhere else", namely in Jefferson et al. 1991 (the link was posted several times on the last page by both creature386 and myself), which gives several other sources for the claim that orcas can bring down large baleen whales on their own or in small groups. Otherwise I wouldn't have found it in the first place: "Although not all attacks on large whales by large groups of Killer Whales (over five animals) were seen to be successful, most instances in which a kill or feeding took place involved relatively large groups of predators. There is some evidence, however (much of it from the whaling literature), to suggest that singles or groups of two or three Killer Whales can, at times, overcome and kill large baleen whales (Eschricht, 1866; Bullen, 1898; D.L. Kelly, unpubl.; Reeves & Mitchell, 1988). It is possible, however, that larger Killer Whale groups may have split up in some of these instances to feed on several whales." Jefferson et al. 1991→, p. 159 You might just have to get rid of the delusion that an orca as an individual doesn't have greater predatory capabilities than a shark several times smaller. You may have the opinion that sharks are more formidable at parity, but regardless of that, the above is plainly a ridiculous claim. "Recent, documented scientific cases"? You mean a single blog post devoting all of a single sentence to what in one of several possible scenarios could have been the unsuccessful attack of a great white shark on a small female Pseudorca? Again, that has nothing to do with it, and neither with their trophic levels or what would happen in a confrontation between the two. And do you see me doubting that they found a false killer whale with shark bite wounds that subsequently died? No, you won't, but you are jumping to conclusions regarding the inferences to take from it. You know what? Believe what you want, you already wanted to end this discussion anyway! |
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Post by elosha11 on Oct 6, 2014 18:42:46 GMT 5
Still got work deadlines, will have to catch up and respond to all of this when I have the time. But I would caution Grey and Theropod not to get too upset with each other. You're both making good points, and if you look closely at your posts, I think you'll actually see there's a large amount of agreement. It's just interpreting the fine print details, which makes all of us crazy sometimes...
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Post by creature386 on Oct 6, 2014 19:19:58 GMT 5
You're both making good points, and if you look closely at your posts, I think you'll actually see there's a large amount of agreement. It's just interpreting the fine print details, which makes all of us crazy sometimes... Yeah, I feel like this is extremely common in debates that go in detail and when both debaters are relatively intelligent. I have enough experience to say this. |
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stomatopod
Junior Member
Gluttonous Auchenipterid
Posts: 182
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Post by stomatopod on Oct 6, 2014 19:35:09 GMT 5
A few points:
GWS are Apex predators, the only documented predations on it are on juveniles/subadults.
If you dont think this is valid,(though there is no compelling reason why one should do so)
they are on top of the tertiary consumers.
Adult GWS eat mostly marine mammals, seals, dolphins, beaked whales, mysticete juveniles and tuna/other sharks.
On the old CF there even was a report of a single, juvenile orca beging killed.
FKW mostly eat squid and fish, very rarely dolphin and juvenile/neonate mysticetes.
Flesh-grazing is facultative parasitism, also practised by gulls.
Most variants of Orca mostly feed on small to medium sized fish. Mammal eating populations mostly feed on Seals and smaller cetaceans.
The largest prey taken regulary are minke whales and elephant seals. Minke whales are pretty small for a mysticete, offen smaller than the orcas themselves. Attacks tergetting adult mystecetes of larger sizes are pretty rare and a work of hours. Other marine predators usually are not capable of this because they are not capable to restrict the whale from fleeing. But we know what happened to that poor blue whale caught between reefs...
While I agree that type A orcas and co can target larger prey on their own than GWS this is not by much, maybe up to a factor of two, but likely even less
C. carcharias is more equipped towards macrophagy due to its dentition, where killer whales are more restricted(They aint Squalodon afterall ;-) )
They can partially make up for this with their cooperative behavior, though.
And FKW have a significatly smaller maximum weight than GWS 1.9 tons vs. 3.3 tons.
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Post by theropod on Oct 6, 2014 22:13:23 GMT 5
That’s only maximum size, average size doesn’t seem too different given that male FKWs mature at 500cm. And what they lack in maximum size they can arguably make up for with the help of the pod. Also it’s not sure whether the giant Cuban shark was actually weighed or whether the weight was just an estimate ( link→). Its true that Great white sharks would be expected to prey on proportionately larger prey than mammal eating orcas, but it doesn’t seem to be the case, the biggest that has been recorded is approximately the shark’s own size. As I noted, that’s a bit strange. EDIT: Perhaps that’s due to the still-underrated factor of ramming as a means of killing in odontocetes, Ford et al. (2005) report "repeated ramming" to be a common method of dispatching minke whales, but not biting. The shark in the account (Pyle et al. 1999) was estimated at 3-4m (thus probably already transitioned to a mammalivorous diet, if that’s what you are getting at), and was killed by a small, if adult, female Orca (estimates 4.7-5.3m long, typical adult size is 7m). Theres no reason to believe trophic interactions between more typical or large-sized orcas and great whites would be different. And just like other marine apex predators, they appear to mostly feed on comparatively small prey, that is pinnipeds in adults and fish in young sharks. Tricas & Mccosker (1984) compiled data on the diet of 33 great whites, and fish was the most common prey item, followed by pinnipeds (cetaceans being uncommon). In the 9 sharks from California (EDIT: from short of 2m to over 5m long btw) analyzed in the study, the stomach contents consisted entirely of fish. Its the young sharks that mostly prey on fish, while adults mostly take seals in most cases. But attacks on juvenile mysticetes ( Three cases→) and beaked whales (one successful here→, involving a juvenile cuvier’s whale) are still a rare ocurrence for any white shark, especially compared to the huge amount of data on their diets. Flesh-grazing can be parasitism, but seagulls don’t force sperm whales to form a marguerite formation, do they? Some forms of flesh-grazing are more akin to predation, namely those involving a full-on attack. Doing that on sperm whales is quite indicative of macropredatory habits, after all even orcas only rarely attack them.
References:Ford, J. K. B.; Ellis, G. M.; Matkin, D. R.; Balcomb, K. C.; Briggs, D.; Morton, A. B. : Killer Whale Attacks on Minke Whales: Prey Capture and antipredator Tactics. Marine Mammal Science, 21 (2005); 4; pp. 603–618 Pyle, P.; Schramm, M. J.; Keiper, C.; Anderson, S. D.: Predation on a White Shark (Carcharodon carcharias) by a Killer Whale (Orcinus orca) and a possible case of Competitive Displacement. Marine Mammal Science, Vol. 15 (1999); 2: pp. 563–568. Tricas, T. C.; McCosker, J. E.: Predatory Behaviour of the White Shark (Carcharodon carcharias) with notes on its biology. Proceedings of the California Academy of Sciences, Vol. 43 (1984); 14; pp.221-234 |
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Post by creature386 on Oct 7, 2014 0:16:31 GMT 5
So, what do we actually use for comparing the ecologic role? Haven't you once said that one should better not use the average size of a komodo dragon to determine its role in the ecosystem? I also favor average size, but it handicaps the slower growers a bit, so this is debatable.
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Post by theropod on Oct 7, 2014 0:38:57 GMT 5
Komodo dragons fulfill several different roles in their ecosystem, depending on their size. Something similar appears to be the case between growth stages of great white sharks (fisheater vs pinniped eater) and obviously ecotypes of orcas, however they are taxonomically distinct from each other.
I think we need further data on the size of false killer whales, my statement bases on a single figure in a single paper. But While some extraordinarily large great whites plausibly reach larger sizes (as the Cuba specimen demonstrates), on the whole they seem rather comparable. Now, of course it’s not the size of freak specimens that determines what trophic interactions between the two are likely to look like.
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Post by Grey on Oct 7, 2014 9:34:36 GMT 5
I agree with this but regarding Pseudorca, with GWS their diet does not largely overlap. The datas about FKW diet I've collected is just obvious, they are primarily squid and fishes eaters, adults great whites prey on larger, mostly warm-blooded preys items. Killing a the occasionnal smaller dolphin or a humpback calf (just based on the content of one FKW individual), presumably in pod, does not put the FKW on the same step than the GWS as apex predator.
The sources of Compagno predates the sources I've posted too, it does not change that the more recent observations just show that occasionnally FKW can target small cetaceans, have maybe on one instance eaten baleen whale calf and the practice flesh grazing on sperm whales, a paratici-like feeding style known among sharks too, including the cookiecutter. That does not change that FKW just do this less often, more occasionnally than adults GWS which are just made for this.
I highly question this observation because :
- it is old, and old observations, even scientific, are prone to vague interpretations and exagerations. 50 years ago, scientists seriously considered GWS to be cold man-eaters (Victor Copelson), do we need to rely on this at now ?
- I cannot found any reliable, recent documented case where a sole orca has been observed killing an adult baleen whale. But I'd be interested to see this.
The examples you cite involve terrestrial much smaller predators than both orca and GWS. I have the sheer impress, and that needs to be investigated, that the bigger is the predator, the less big are its preys items compared to it, individually. I just don't know any case where a lone orca attacked and killed a prey twice its size. That is certainly more difficult to verify since orcas normally hunt socially and that even if only one can kill a prey, all the pod is actually doing it.
GWS are reported to prey adult bull elephant seals, which can easily exceed the shark body mass, pilot whales which most species are usually larger than large GWS and right whales calves which are already extremely massive even for GWS standards. So I have data that GWS can at least attack preys as larger or larger than themselves. I don't have such data for orcas, possibly partly because they are social and all the time do the job in pods.
There's a misunderstanding here. I don't say that the orca cannot kill bigger game than GWS, of course it can in absolute termes given its much larger size. I ask evidences that it can kill individually larger prey items proportionnally to its size than GWS, if this ever happens as the orca is pack hunter and that even a smaller-sized minke whale is usually dispatched by the entire pod.
The prey size they can take is similar, but FKW does it (much) more rarely than GWS, which does it individually.
Beware with the meaning of "attack". A single orca has already been observed harrassing by its own cow sperm whales or baleen whales, in a tactical context. No, that's not what I refer, I'm asking an evidence where an orca individual has attacked, severely wounded and/or killed by its own a much larger prey item. And not one based on a 140 years old observation, at a time when scientists reported 18 m long anacondas in the Amazonian forest...
No my primary opinion is that a 3 tons orca and a 3 tons white shark would have, regardless of their physical and behavorial specificities, a similar individual predatory power and that the max prey size they could take might similar. I just don't think that a 8 tons orca can attack and kill a 35 tons humpback.
All what I say is that we have at least minor hints and suggestions that GWS perhaps, rarely, preys on FKW, whereas we have absolutely no indication of the other situation (FKW attacking/killing/feeding on GWS). But I do not count FKW as a prey for a GWS until something more solid comes about this interspecific relationship. But I don't consider the FKW as equal to the GWS as apex predators, they are primarily squids and fishes predators, mammalian preys only appear occasionnal.
I don't think the Cuba specimen is the typical record sized specimen after all, last time I've checked it was said to be 5.94 m. But seemed quite hefty for its size. The Malta and Kanga specimens are more serious candidates as largest specimens.
Because a pod of FKW certainly appears more theatening than seagulls. It doesn't change that FKW had no intention to kill the sperm whales, that's no effective predation. I think that flesh grazing has been suggested for GWS too on adults humpbacks.
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If that was so easy. Taxa have been proposed in works of hundreds of pages, and yet are considered nomina dubia.
