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Post by nocap on Sept 22, 2021 23:46:28 GMT -5
Orcas, also known as killer whales, are among the world’s most easily recognized marine mammals. The largest member of the dolphin family, orcas are highly intelligent and social animals, spending their lives in groups or pods where they hunt together and share responsibility for raising young and taking care of the sick or injured. Adult orcas have shiny black backs, white chests and patches of white above and behind their eyes. They have paddle-shaped pectoral fins and tall triangular dorsal fins. Their distinct coloring mean they are easy to identify and rarely confused with other dolphins or whales. Orcas vary in size depending on where they live. Adult males are larger than adult females, with males reaching 32 feet (10 meters) in length and females growing to 28 feet (8.5 meters).  |
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Post by nocap on Sept 22, 2021 23:48:48 GMT -5
Average size data by lengths (cm); the mean is 667.5cm, which would result in the average bull orca weighing ~6600kg.  |
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Post by Gorilla king on Sept 23, 2021 3:58:34 GMT -5
Great thread nocap. I basically have no idea about killer whales, never did any research on them, but very interesting animal for sure. Here are the different types:
“Why are there so many different types of killer whales?”
Killer whales are found in every ocean of the world. They are the most widespread mammals other than humans. While they are all technically the same species (stay tuned – there has been talk about reviewing species and subspecies distinctions), they are all separate breeding populations, each with their own language, social structure, food preference and hunting behaviours – essentially their own culture. This is passed on from the older generations to the younger ones the same way it is in humans. So while technically, the different ecotypes can interbreed and produce fertile offspring (thanks, SeaWorld, for proving that one [cough sarcastically]), in the wild, they don’t. Showing that they are much smarter than humans, they seem to have some sort of silent agreement that even though they may live in the same waters, since they’re not competing for the same resources, they generally just avoid each other. No fighting! No war! No genocide! Everyone wins.
It is likely that the different ecotypes evolved in different places (perhaps separated by glaciers, etc.), learning to feed on whatever prey was abundant in their area. By the time they found themselves in the proximity of other killer whales, they had been reproductively isolated for so long that the thought of interbreeding probably didn’t even occur to them. In BC, Bigg’s (or Transient) Killer Whales are thought to have diverged from other killer whale populations over 700,000 years ago. This is known as cultural divergence.
In the North Pacific, there are three distinct ecotypes: Resident (fish eaters who prefer Chinook salmon) and Bigg’s (or Transient) Killer Whales (connoisseurs of marine mammals) occur in the coastal waters of the North Pacific, and Offshore killer whales (with a preference for sharks) are mostly found, you guessed it, offshore. The same sort of distinctions occur in the North Atlantic: Type 1 Eastern North Atlantic prefer herring or mackerel, which are plentiful there, and Type 2 Eastern North Atlantic prefer marine mammals, mostly other whales and dolphins.
In the Southern hemisphere around Antarctica, there are at least 5 different ecotypes of killer whales. (We’ll forgive researchers for not being certain about this, as it is a rather harsh and inhospitable climate). Antarctic Type A killer whales tend to stay away from the ice and feed mostly on minke whales. Type B have recently been split into two groups: Pack Ice Killer Whales feed on seals around the outer pack ice, and smaller Gerlache Killer Whales (named after the Gerlache Strait on the Antarctic Peninsula in which they are often found) feed mainly on penguins. Type C or Ross Sea Killer Whales are piscivores, feeding mainly on fish and following channels or openings in the pack ice. Types B and C have a distinctive yellowish colour from diatoms on their skin, as well as a prominent dorsal cape. Type C is the smallest known killer whale ecotype. Last but not least is the Type D or Subantarctic Killer Whale, who with its tiny eyepatch and distinct shape, has been seen only a few times, usually stealing fish from longlines.
So there you have it. It is also important to note that while there are three ecotypes of killer whales in BC, they are further separated into distinct breeding populations. The endangered Southern Resident Killer Whale population, the best known in the world (thank you Center for Whale Research for 40 years of study, and Dr. Mike Bigg for pioneering the photo-identification techniques we still use today), contains only 83 animals. The Northern Residents, also fish-eaters, are a much larger population, numbering almost 300 animals. Bigg’s killer whales are also separated into several distinct breeding populations. So you see, conservation is not just about whether or not two animals can breed together to produce offspring; it is about ensuring the continuity of the culture, the language, the way of life… much as it is in humans. If the SRKW population continues to dwindle, would they eventually inter-breed with the Northern Residents? Observations of the AT1 population of Bigg’s killer whales in Alaska, who were severely affected by the Exxon Valdez oil spill, indicates that they won’t. But let’s hope we never have to find out.
www.eaglewingtours.com/articles/killer-whale-ecotypes-explained-nutshell/
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Post by Gorilla king on Sept 23, 2021 4:09:41 GMT -5
Killer whale ecotypes: Is there a global model?
Abstract and Figures
Killer whales, Orcinus orca, are top predators occupying key ecological roles in a variety of ecosystems and are one of the most widely distributed mammals on the planet. In consequence, there has been significant interest in understanding their basic biology and ecology. Long-term studies of Northern Hemisphere killer whales, particularly in the eastern North Pacific (ENP), have identified three ecologically distinct communities or ecotypes in that region. The success of these prominent ENP studies has led to similar efforts at clarifying the role of killer whale ecology in other regions, including Antarctica. In the Southern Hemisphere, killer whales present a range of behavioural, social and morphological characteristics to biologists, who often interpret this as evidence to categorize individuals or groups, and draw general ecological conclusions about these super-predators. Morphologically distinct forms (Type A, B, C, and D) occur in the Southern Ocean and studies of these different forms are often presented in conjunction with evidence for specialised ecology and behaviours. Here we review current knowledge of killer whale ecology and ecotyping globally and present a synthesis of existing knowledge. In particular, we highlight the complexity of killer whale ecology in the Southern Hemisphere and examine this in the context of comparatively well-studied Northern Hemisphere populations. We suggest that assigning erroneous or prefatory ecotypic status in the Southern Hemisphere could be detrimental to subsequent killer whale studies, because unsubstantiated characteristics may be assumed as a result of such classification. On this basis, we also recommend that ecotypic status classification for Southern Ocean killer whale morphotypes be reserved until more evidence-based ecological and taxonomic data are obtained.
Marion Island killer whales showing different morphological characteristics often used to delineate the Antarctic ecotypes. Note that male M005 has characteristics consistent with both Type A (medium sized eyepatch) and Type B (dorsal cape) ecotypes. (A) Male killer whale (M005)—note the faint dorsal cape. (B) Male killer whale (M005)—note the medium sized eyepatch. (C) Female killer whale (M014)—note the dorsal cape and medium to large eyepatch.
Type C killer whales in McMurdo Sound, Ross Sea showing variation in morphological features. Both have the angled eyepatches characteristic of the type; however (A) has a large eyepatch and no obvious dorsal cape, while (B) has a considerably smaller eyepatch and a prominent dorsal cape.
www.researchgate.net/publication/230654314_Killer_whale_ecotypes_Is_there_a_global_model
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Post by Gorilla king on Sept 25, 2021 15:38:42 GMT -5
Killer whales (Orcinus orca) attack and kill a Bryde's whale (Balaenoptera edeni)
Abstract
On 3 May 1988, we observed a group of killer whales that pursued, killed, and partially consumed a Bryde's whale in the northern Gulf of California, Mexico (31°01′N, 114°15′W). The attack was observed from 06:54 to 08:53 while circling in a single-engine aircraft at an altitude of 160 m. The group comprised about 15 killer whales, including two adult males and at least two calves. Females and (or) subadult males pressed the attack most intently. The killer whales tore skin and blubber from the right flank of the Bryde's whale, and on 11 occasions the killer whales swam onto the head or back of the Bryde's whale, which hindered its breathing. The respiration intervals of the Bryde's whale were short and irregular, and blow rates differed significantly from those of undisturbed Bryde's whales. Fatiguing the whale may have facilitated an easier kill by asphyxiation. After the death of the Bryde's whale, the two adult male killer whales surfaced slowly about 200–300 m away from the remainder of the group, which presumably fed on the submerged Bryde's whale carcass. Two days later, the drifting Bryde's whale carcass was located. A large wound was visible on the abdomen, and sections of the lower jaw had been removed. Like those of canids and some felids that hunt cooperatively when preying on ungulates, attacks by Orcinus orca exhibit coordination of activities and efficiency in dispatching prey.
www.researchgate.net/publication/238021609_Killer_whales_Orcinus_orca_attack_and_kill_a_Bryde's_whale_Balaenoptera_edeni
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Post by Gorilla king on Sept 25, 2021 15:50:38 GMT -5
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Post by nocap on Sept 25, 2021 16:33:13 GMT -5
Orcas often attack other types of orcas as they're smart enough to distinguish between say a transient orca and a resident orca - why does this happen? A rather controversial topic, but i believe this is because they have different cultures (yes, orcas are racists) and competition. Below i show an account of residents and transient orca conflict. This was one incident where about 13 residents attacked 3 transients. The author thinks that transients might avoid residents (and they apparently do this more often than vice versa) because the latter often outnumber the former, even though residents are specialized piscivores, it also suggests that residents prey upon juvenile transients.  Pictured - a female orca injured in combat  |
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Post by nocap on Sept 25, 2021 16:35:25 GMT -5
The differences between the dorsal fin in the three orca types:  |
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Post by nocap on Sept 25, 2021 16:47:42 GMT -5
Orca predation upon sperm whales: "But there are other observations that suggest that killer whale attacks on sperm whales are not all that rare, and perhaps not always unsuccessful. Shevchenko (1975) reported that 65% of sperm whales taken by whalers in Antarctica had killer whale teeth marks on them. Rice (1989) discredited this last report saying that it would be difficult to distinguish tooth marks of killer whales from those of other sperm whales, but Shevchenko (op, cit.) found the same tooth marks on fin, sei, and minke whales (Balaenoptera physalus, B. borealis, and B. acutorostrata, respectively). Also, it seems unlikely that an experienced cetologist like Shevchenko would mistake the very different tooth size and placement, and jaw configuration of a killer whale with that of a sperm whale"  But it remains true that orcas attack sperm whale bulls in rare cases only, as explained by pitman here:  From 8:42 Orcas actually steal kills of bull sperm whales AKA giant squids Orcas attempt predation on young sperm whale bull, who escapes through going under the boat Orca pod attacks group of 3 gigantic sperm whale bulls |
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Post by Gorilla king on Sept 25, 2021 18:19:57 GMT -5
Nice accounts and videos bro. So orcas are like lions and bears. Like lions because they run in pods, like bears because they steal kills from whales.
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Post by oldindigosilverback on Sept 25, 2021 22:36:50 GMT -5
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Post by oldindigosilverback on Sept 25, 2021 22:39:33 GMT -5
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Post by Gorilla king on Sept 26, 2021 0:52:02 GMT -5
Reply #10, great video, after watching just a few videos and accounts i can clearly see that orcas completely dominate. I cant even see a gws winning a one vs one fight to be honest, the orca is just too large. Am starting to like orcas.
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Post by Gorilla king on Sept 26, 2021 1:11:42 GMT -5
nocap What is the average weight of gws? I searched around but different sites state very diffefent weights. What is the most reliable figure?
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Post by nocap on Sept 26, 2021 2:00:46 GMT -5
nocap What is the average weight of gws? I searched around but different sites state very diffefent weights. What is the most reliable figure? Adult female great white sharks are generally 475cm in length; here's a chart from literature crafted by multiple experts using a reliable equation:  So based of this the average sized great white shark would weigh a little under 1000kg while the largest would weigh around 2000kg, an average sized orca would weigh around 6600kg while the largest would weigh a little over 10000kg. A size comparison showing how an orca bull would look next to a great white shark, and this isn't even antarctic type A bulls that average over 7000kg.  |
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Post by arctozilla on Sept 26, 2021 4:32:56 GMT -5
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Post by Gorilla king on Sept 26, 2021 9:02:42 GMT -5
Even if we take the largest gws, at around 2000 kg, how is it going to defeat an average sized orca at 6600 kg? Any account of a gws winning nocap ?
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Post by nocap on Sept 26, 2021 9:05:01 GMT -5
Even if we take the largest gws, at around 2000 kg, how is it going to defeat an average sized orca at 6600 kg? Any account of a gws winning nocap ? Yeah, it can't. There's no accounts of great whites killing orcas; they typically flee areas with orcas and do not return for a long time, they're terrified of orcas. |
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Post by Gorilla king on Sept 26, 2021 9:10:28 GMT -5
With good reason.
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Post by nocap on Sept 26, 2021 9:11:54 GMT -5
Yeah, you can't blame them; i myself would be terrified of a bunch of 6 ton bullies that hunt down whales weighing over 30 tonnes and roam in pods. And want to extract my liver and throw my dead body away. |
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