AboutWhales: Whale

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Whale statistics - these are very variable. If you do any research on whales on the internet, or in books, you will find that there are wide differences in the recorded length and mass of the various species. Lengths are generally more reliable than weights as it easier to measure the length of a whale, from whalers records or from photographs against objects of known size. The weight on the other hand is very difficult to measure and is often based on some rough measurements and estimates from those measurements of whales caught by whalers.

Unlike other animals it is not possible to guide a whale onto a weigh bridge or to suspend it from a crane to measure the weight (or even take it to the whale-weigh station, arf!). The only time whales have been available in quantity for such statistics was during the old whaling days and then it was most important to get them processed as quickly as possible before the next one arrived, so weights are educated guesses at best.

Blue whales

The largest animals ever to have lived, dwarfing even the largest dinosaurs. All figures about blues are awesome. Their circulatory system pumps 10 tonnes of blood through its body using a heart the size of a small car. A child could crawl down the whales' main blood vessel, the aorta. In its development, a blue whale calf can drink 50 gallons of its mother's milk and gain 200lbs per day!

The largest individuals have been estimated at being 150-200 tonnes.

Blue whales are light grey/blue to dark grey while at the surface, but seen underwater they are a luminous aqua blue.

Right Whales

The name was given by the early whalers because they were the "right" whales to kill. They have large amounts of oil, blubber and baleen or whalebone, they are slow swimming (easy to catch), are often found close to shore and float when killed.

Right whales have a large bulbous head and lack the streamlined shape of other whales. The head has large callosities that are home to a whole colony of whale barnacles, parasitic worms and whale lice.

Sei whales

These are among the more elusive of the larger whales, not coming very close to land at any time and not forming large groups or "schools". Sei is pronounced "Say"

They are found like many whales in both Northern and Southern hemispheres following the best feeding at different times of year. Only the larger older individuals tend to go very far south, they are relatively rare in Antarctica

Humpback whales

So called because of the habit of raising and bending the back in preparation for a dive, accentuating the hump in front of the dorsal fin.

Probably the best known of the large whales as they often collect in groups near to land and draw attention to themselves by their behaviour. Breaching, lob-tailing and flipper-slap are common and often occur several times in a row.

They are slow swimmers (allows tourist boats - and whalers - to get close). Males at breeding time sing the longest and most complex songs in the animal kingdom.

Minke whales

One of the smallest baleen or filter feeding whales. Minke numbers are still quite healthy due to whalers concentrating on larger, more profitable species.

Minkes are still hunted for "scientific" reasons by Japan, and large quantities of the meat turns up in expensive restaurants.

Fin whales

The second largest after the blue whale, the fastest swimming of all the large whales (sometimes called the greyhound of the seas) and the commonest large whale.

Fin whales can produce sounds of 75-80dB at around 100Hz which is very loud for an animal source. In pre-propeller oceans this sound could travel for well over a hundred kilometres.

Sperm whales

The name comes from the enormous bulbous spermaceti organ in the head.

Only males are found in Antarctic waters. Sperm whales are toothed whales rather than filter feeders and are the deepest and longest of all whale divers catching giant squid in the dark ocean depths.

Unlike baleen whales, which form only temporary bonds, sperm whales live in extended family units that for the females are lifelong associations.

Killer whales

Also known as Orcas from their Latin name. They are one of the most well known types of whales thanks to their being held captive in marine aquariums where they are taught to perform tricks.

Killer whales are toothed whales and top carnivores in their food chain. Sometimes referred to as "sea-wolves", they frequently hunt in packs or "pods". Their tastes are wide ranging from krill and fish to penguins, seals and even much larger baleen whales.

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A comparison of the size of baleen whales, the bowhead and grey whales are not species found in Antarctica

At Monterey - In what is probably the first time such an event has been witnessed and recorded, humpback whales appeared to try to intervene when a pod of killer whales attacked a baby gray whale.

Spring is a dynamic time for whale watching in Monterey Bay, California – gray whales are migrating north with calves in tow, blue whales move into the area to feed, and humpback whales return from their winter migration. Transient orcas (killer whales) are also present, as this eco-type of orca utilizes other marine mammals as a primary food source.

Humpback Whales follow in Killerwhale Attack on GrayWhale 1

Skilled at killing even large whales, they regularly take the calves of gray whales – hard as it is to witness, this is a normal predator/prey relationship. But what occurred on May 3rd, 2012 in full view of whale watchers was nothing short of remarkable.

Humpback Whales follow in Killerwhale Attack on GrayWhale 2

Gray Whale Calf: this calf was completely exhausted, under attack by the orcas for at least 30 minutes. Its mother is holding it up.

Through the hazy overcast skies, the Monterey Bay Whale Watch boat captain John Mayer on the SeaWolf ll, spotted the whales in the distance and knew something unusual was going on. As the boat drew closer to the scene, whale watchers were stunned by what they saw. A pod of approximately nine transient orcas was in the process of trying to separate a new calf from its mother, but what amazed even the seasoned captain and crew was the presence of two large humpback whales which may have been trying to intervene.

Humpback Whales follow in Killerwhale Attack on GrayWhale 3

Two humpbacks were present throughout the attack, and were joined shortly after the attack ended by five more.

The mother gray whale struggled valiantly to save her calf, lifting it out of the water to breathe, but she was no match for the coordinated attack as the orcas repeatedly grabbed the fatigued calf and flipped it upside down to prevent it from breathing. During the half hour that the first group of whale watchers observed the contest for survival, the two humpbacks splashed, ‘trumpeted’, and moved in as close as a body length from the grey whale mother and her calf.

At this point, whale researchers Alisa Schulman-Janiger and Nancy Black arrived on the scene in Monterey Bay Whale Watch boat Pt. Sur Clipper, and continued to observe the unusual encounter for nearly seven hours. Shortly after their arrival the baby whale was killed, and the mother took temporary refuge by their boat before heading towards shore.

Schulman-Janiger said that first two, then three more humpbacks joined the original pair, and the seven humpbacks “repeatedly followed the orcas, trumpet blowing, tail slashing, rolling, and head raising. They kept returning to the area of the carcass where the orcas were ripping into the blubber of the dead calf”.

Humpback Whales follow in Killerwhale Attack on GrayWhale 5

A humpback whale follows a subgroup of orcas. This was the most common orientation seen: humpbacks following the orcas (rather than the reverse), sometimes at increased speeds.

Researcher Nancy Black speculated that these humpback whales may have been protecting the carcass, making it more difficult for the orcas to feed, but without underwater cameras it is difficult to be certain.

“What we do know”, said Schulman-Janiger, “is that these humpback whales seemed EXTREMELY distressed: nearly every surfacing over the entire observation period was accompanied by trumpet blows. They even put themselves into potential harm’s way by diving right next to the gray whale mom – where her calf was under attack”. She noted that humpback whales were documented to have rescued a seal from orcas in the Antarctic, and underscored the importance of continuing to protect these whales while we gain more understanding.

Dr. Lori Marino, senior lecturer in neuroscience at Emory University in Atlanta, is a renowned expert in the cognitive ability of whales and dolphins and she shared her opinion of this remarkable event:

This is apparently a case of humpback whales trying to help a member of another cetacean species. This shows that they are capable of tremendous behavioral flexibility, giving even more credence to reports of cetaceans coming to the aid of human beings. They seem to have the capacity to generalize from one situation to another and from one kind of being to another. Moreover, they seem to sympathize with members of other species and have the motivation to help.

One reason may be that humpback whales, and many other cetaceans, have specialized cells in their brains called Von Economo neurons (“spindle cells”) and these are shared with humans, great apes, and elephants. The exact function of these elongated neurons is still unknown but they are found in exactly the same locations in all mammal brains for the species that have them.

What is intriguing is that these parts of the mammal brain are thought to be responsible for social organization, empathy, speech, intuition about the feelings of others, and rapid “gut” reactions. So the presence of these cells is neurological support for the idea that cetaceans are capable of empathy and higher-order thinking and feeling.

In either case these whales are apparently demonstrating a high level of sensitivity and concern (morality, if you will) that is laudable in any species.

Humpback Whales follow in Killerwhale Attack on GrayWhale 4

Killer whales Description

Weight: males can weigh up to 22,000 pounds (10,000 kg); females can weigh up to 16,500 pounds (7,500 kg)

Length: males can reach 32 feet (10 m); females can reach 28 feet (8.5 m)

Appearance: black on top with white undersides and white patches near their eyes; highly variable gray or white saddle behind the dorsal fin; these markings are unique across individuals and populations

Lifespan: up to 50-100 years: males typically live for about 30 years, but can live as long as 50-60 years; females typically live about 50 years, but can live as long as 100 years

Diet: varies (diet is often geographic or population specific), can include fish, marine mammals, sharks, and sea birds

Behavior: highly social animals, living within matriarchal societies; rely on underwater sound for orientation, feeding, and communication; produce whistles and pulsed calls, used for communication and maintaining group cohesion

Killer Whale Ecotypes and Forms poster

Credit: NOAA Southwest Fisheries Science Center

Killer whales most widely distributed marine mammals, found in all parts of the oceans; most abundant in colder waters, including Antarctica, the North Atlantic and Pacific Oceans. They also occur, though at lower densities, in tropical, subtropical, and offshore waters.

Killer whales are generally considered monotypic (belonging to one species). However, genetic studies and morphological evidence have led many cetacean biologists to now consider the existence of multiple species or subspecies of killer whales worldwide.1

The species shows considerable size "dimorphism". Adult males develop larger pectoral flippers, dorsal fins, tail flukes, and girths than females.

Female killer whales reach sexual maturity when they grow to about 15-18 feet (4.6 m-5.4 m) long, depending on geographic region. The gestation period for killer whales varies from 15-18 months. Birth may take place in any month--there is no distinct calving season. Calves are nursed for at least 1 year, and may be weaned between 1-2 years old. The birth rate for killer whales is not well understood, but, in some populations, is estimated as every 5 years for an average period of 25 years.

Killer whales are highly social animals that occur primarily in relatively stable social groups that often range in size from 2 to 15 animals. Larger groups (rarely as large as several hundred individuals) occasionally form, but are usually considered temporary groupings of smaller social units that probably congregate for seasonal concentrations of prey, social interaction, or mating. Single whales, usually adult males, also occur in Bigg's killer whale populations (as discussed below). Differences in spatial distribution, abundance, behavior, and availability of food resources probably account for much of the variation in group size among killer whale populations.

Populations and Social Organization

Scientific studies have revealed many different populations--or even potentially different species or subspecies--of killer whales worldwide. These different populations of killer whales may exhibit different dietary needs, behavior patterns, social structures, and habitat preferences. Therefore, interbreeding is not expected to occur between different populations, in spite of the overlap between home ranges.

The most well-studied killer whale populations occur in the eastern North Pacific Ocean. Three distinct forms, or ecotypes, of killer whales are recognized:2

Resident
Transient, or Bigg's
Offshore

The three types differ in morphology, ecology, behavior, and genetics. A recent genetic study3 suggests the transient type has been separated from all other killer whales for approximately 750,000 years and might represent a separate species or subspecies, known among researchers as Bigg’s killer whales. All three types of killer whales share at least part of a home range, yet they are not known to intermix with one another. The resident and transient types both have multiple populations within their range.

Source: http://www.nmfs.noaa.gov/pr/

Péos, Mininos, Cécil, Teha, and Amtan are performing dolphins at the Planète Sauvage dolphinarium in Port-Saint-Père, France. Every day, as music and sounds of the sea play in the background, they show off their swimming, jumping, and ball-catching skills for an adoring audience and squawk and whistle just like dolphins should. But at night, they make strange noises that researchers believe are imitations of humpback whale songs included in the performance soundtrack. If so, the identification of this unexpected repertoire would mark the first time that dolphins have been heard to rehearse new sounds hours after hearing them rather than right away, providing insights into how they store and process memories.

Researchers discovered the dolphins' midnight melodies by accident. Ethologist Martine Hausberger of the University of Rennes 1 in France and her colleagues had hung underwater microphones in the tank because little is known about what dolphins sound like at night. One night, they suddenly heard 25 new sounds (see below) that the dolphins had never made before, although they weren't sure which of the five animals was talking. Because dolphins are known for mimicry, the researchers examined their complex daytime environment to determine where the noises might be coming from. They finally zeroed in on the new soundtrack that Planète Sauvage was playing during performances, which included music, sea gulls' calls, the dolphins' own whistles, and humpback whale calls.

When the researchers used a computer program to compare auditory recordings of the whale calls with the mysterious nighttime noises, it showed that the two sounds were very similar. And because the dolphins had been captive their entire lives, they couldn't have picked them up from real whales.

To get a second opinion, the team asked 20 human volunteers to listen to humpback whale sounds and wild dolphin sounds. Then the researchers played the nighttime vocalizations and asked the volunteers whether the sounds came from a whale or a dolphin. About 76% of the time, the volunteers classified the imitations as sounds from real whales, the researchers reported online in December in Frontiers in Comparative Psychology. Until now, dolphins have been known to mimic sounds (including whale sounds) only right after hearing them. Because the dolphins didn't make these noises during the show, the finding suggests that they waited to practice the sounds hours later.

So why would dolphins want to mimic whales? Hausberger believes that it might be because the shows prime the animals to learn and remember information. "The shows are a really special time in the day," she says, because the dolphins get rewards for performing well. During the rest of the day, the park is open and people can view the tank, chatter, and applaud. "There are lots of things they could mimic but don't. ... It's really remarkable the only mimicry [we] found was this one." She wants to find out whether the dolphins are asleep and dreaming when they mimic, which might mean that dreams help dolphins etch new information into their memories, just like in humans. She plans to capture electroencephalogram recordings of the dolphins' brains at night, which would show whether this is the case.

Peter Tyack, a biologist at the University of St. Andrews in the United Kingdom who studies animal vocalization, says that the idea that dolphins might delay their rehearsals for hours is intriguing. But he isn't convinced from the small number of recordings that the researchers obtained that the dolphins were imitating whales. "I have heard sounds in the field that sound quite a bit like the [whalelike sounds]," he says. In addition, he says, dolphins make so many different sounds that it's difficult to pin down one as an imitation of a particular source. But songbirds rehearse their imitations of other noises at night, so he thinks it's not unlikely that dolphins might do the same.

Types of whales in the world.

Humpback Whales follow in Killerwhales Attack on Gray Whale Calf

Killer whales description and social organization.

Can dolphin speak whale voice?

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