Orcas hunt in deadly pods, family groups of up to 40 individuals. There appear to be both resident and transient pod populations of orcas.
These different groups may prey on different animals and use different techniques to catch them. Resident pods tend to prefer fish, while transient pods target marine mammals. All pods use effective, cooperative hunting techniques that some liken to the behavior of wolf packs. Orcas are protective of their young, and other adolescent females often assist the mother in caring for them. Mothers give birth every three to ten years, after a month pregnancy.
They give birth to one baby at a time, which may nurse for up to two years. In most cases, the bond between juvenile and mother will eventually weaken, and the young orca will go its own way, but in some pods, the juvenile may stay with the pod it was born into its entire life. Orcas are highly intelligent, social mammals that have long been a part of marine park entertainment, performing shows for audiences.
However, it's become increasingly clear that orcas do not thrive in captivity. They have evolved to swim up to 40 miles a day, foraging for food and exercising. They dive to feet, several times a day, every day. Whether they're born in the wild or in captivity, all orcas born have the same innate drive to swim far and dive deep. Artificial enclosures in captivity cannon offer that kind of range to orcas, contributing to boredom and stress.
Orcas have been seen to develop stereotypies, also known as zoochosis—repetitive patterns of activity that have no obvious function, which range from self-mutilation to rocking and swaying. Usually related to stress and inappropriate habitats, stereotypic behavior has been documented in orcas in scientific research since the late s.
There are several drilled out teeth, teeth worn to the gums, and broken teeth in these three photos. There are many more such photos available on the Internet. While less than a handful of juvenile to adult captive killer whales suffer no wear or breakage, this is the exception rather than the rule. These three photos are representative of most captive killer whale teeth.
Killer whale teeth in the wild generally do not suffer severe wear at the tip and only very rarely exhibit breakage and when they do, this wear occurs at the population level and is associated with prey type e. Pacific transient ecotype teeth show slight wear, associated with feeding on other marine mammals Ford et al.
Generally mammal eaters show wear on the sides of the tooth more than on the tip Caldwell and Brown Northeastern Pacific resident and Type 2 North Atlantic teeth suffer no wear at the tip and only some on the sides Ford et al. Norwegian killer whales like to munch on Atlantic herring; it is their main prey. Herring is a small fish: 20 to 38 cm 8 to 15 in , covered in scales.
Killer whales have large mouths and between 40 and 56 interlocked teeth. Their sharp teeth are not made for chewing but for ripping and tear their prey before swallowing it in chunks. So how do Norwegian killer whales eat herring?
They suck it! Extreme tooth wear was not really observed in North Pacific resident killer whales because they feed mainly on larger fish like the chinook salmon 61 to 91 cm — 24 to 36 in , which they tear into large chunks before swallowing. Similarly, North Pacific transients and North Atlantic killer whales that feed on marine mammals have minimal tooth wear because they do not scrap scally prey against their teeth.
Unlike the toothed whale species baleen whales do not possess teeth but instead are born with baleen plates that have bristles attached to them. The bristles of baleen whales are often said to resemble the teeth found on a comb and can be very thin and fine depending on the species of whale. These whales capture their prey by swimming towards it with their mouth open engulfing large amounts of water along with fish , krill , squid and any other prey they are hunting.
They then expel the water out of their mouth using their tongue while leaving their prey trapped inside their baleen bristles. The bristles can also be thought of as a fence that keeps small animals from escaping but allows air to move in and out of it. Because baleen whales do not have teeth they usually end up swallowing their prey whole and almost always search for small prey that is easily digestible such as krill a common food for the blue whale which in most cases measures less than 2 inches in size.
Baleen whales are commonly refereed filter feeders because of the way they capture prey such as fish and krill and trap them in their baleen bristles while allowing water and other small sea sediments to escape through their baleen bristles, much like a filter. Regardless of the species most baleen whales are unable to swallow large prey due to their small throats and almost all species are incapable of eating other marine mammals with the exception of the killer whale and false killer which are both dolphins and belong to the toothed whale suborder, therefore the likelihood of a human ever being consumed by a whale remains extremely low.
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