INFORMATION AND CHARACTERISTICS.

The Long-finned pilot whale is a cetacean member of the Delphinidae family, and one of the largest members of this group. Although it is commonly called “whale,” it is not a whale of the suborder Mysticeti. However, this colloquial name comes from its size and behavior.

The first word of its scientific name means something like “balloon head” as the Latin word “globus” means “balloon or ball” and “cephalas” means “head.”

Order: Cetacea
Family: Delphinidae
Genus: Globicephala

HOW DO THEY LOOK? PHYSICAL CHARACTERISTICS.

Morphology.
It is a relatively large animal with a robust body. It has a head with a bulbous forehead product of the bulging melon. Its beak is very short, and the long and curved line of the mouth gives it a face of a perpetual smile. The pectoral flippers are very long and correspond to a fifth of the total length of its body.

Weight and size.
The female is about 5.8 meters long. There is sexual dimorphism consisting of a bigger growth of the male, which reaches 7.6 meters in length. The female has a body mass of about 1,300 kilograms while the male weighs up to 2,300 kilos.

Skin Coloration.
The skin has a dark gray or black color in the upper dorsal area. The lower ventral region has a long, light gray, anchor-shaped patch that starts from the chest and ends around the genital slits. Behind the dorsal fin lies a small, light, saddle-shaped patch.

Physical characteristics.
It is a little difficult to distinguish this species from the short-finned pilot whale (Globicephala macrorhynchus) except for the length of the pectoral flippers which are larger in Globicephala melas than those of its relative.

WHERE DO THEY LIVE? DISTRIBUTION AND HABITAT.

The Long-finned pilot whale is distributed in the temperate and sub-polar zones of the southern hemisphere and the northern hemisphere and is absent from the tropical areas and the regions near the equator. In the North Atlantic is present in coastal waters and deep waters that include the Mediterranean, Barents and the North Seas and the Gulf of St. Lawrence. It is presumed extinct in the northern Pacific Ocean, but the western part may still be populated. Northern Scotland, Ireland, and Great Britain also have this dolphin.

In the southern hemisphere, it extends as far as the Antarctic Convergence at latitude 68° S in the south part of the Atlantic and Pacific Oceans, mainly near Australia and New Zealand.

Countries and regions whose waters are home to the Long-finned pilot whale are Canada, Denmark, United States, United Kingdom, Greenland, New Zealand, Australia, South Africa, Spain, Sweden, Libya, Italy, Ireland, Iceland, Argentina, Belgium, France, Germany, Falkland Islands, Portugal and Isle of Man.

Their habitat is variable. Some individuals seem to prefer staying close to the coasts while others are always in high seas. The areas where they dwell have high ridges or are on the edge of the continental shelf. The temperature of the waters that this dolphin inhabits is between 0° and 25° Celsius.

WHAT DO THEY EAT? DIET AND EATING HABITS.

The Long-finned pilot whale maintains a diet strictly carnivorous, in its menu excel fish like herring, cod, mackerel, turbot, dogfish and Hake, and cephalopods like the squids of the genus Gonatus and the species Todarodes sagittatus. Populations living in the northeast areas of the Atlantic Ocean eat mainly squid.

A Long-finned pilot whale consumes about 34 kilograms of food per day. Their favorite time to hunt is during the night. They do it submerging 200-600 meters deep to detect prey with the help of its senses, mainly echolocation.

It does not have a good reputation among the fishermen since it takes advantage of the moments in which the boats catch fish to obtain food the easy way.

HOW DO THEY BEHAVE? BEHAVIOR.

Like most dolphins, the Long-finned pilot whale is a very sociable species that form groups of 20-100 and up to 1,000 individuals or more. It seems that family groups are more delimited and not so fluid, that is, there are not many movements between groups and they can stay in their natal pod until all their life.

The family groups are composed of breeding females with inbreeding relationship, their offspring and some males that are not the fathers of their offspring. This behavior suggests a temporary membership to mate with the available females. The social ties are incredibly strong, and some believe that this is the reason for the massive stranding on the beaches: if the theory is correct, the members of a herd follow the one or those who stranded first.

Clicks, whistles, and pulsed sounds are standard in their communication processes.

HOW DO THEY REPRODUCE? MATING AND REPRODUCTION.

The polygamy of the Long-finned pilot whale is evident when a male goes to a pod different from his own in search of a receptive female to mate. The male reaches sexual maturity at around 12 years of age and females approximately at six years.

The courtship process is not very “kind,” on the contrary, the male exhibits an aggressive behavior consisting of blows with his melon to his partner’s melon. If it is successful then it mates, this can happen during any time of the year but more frequently in spring and summer.

15 or 16 months after mating, the female gives birth to 1 offspring of 1.2 to 2 meters in length which is the subject of exclusive maternal care for at least two years.

WHAT IS THEIR CONSERVATION STATUS? THREATS AND CONSERVATION.

Conservation Status: “Data Deficient.”

While humans keep destroying nature, species like the Long-finned pilot whale fear for their survival on Earth. Since the nineteenth century, this and other cetaceans were hunted in the waters of Newfoundland, Greenland, Denmark, Iceland, Norway, Scotland and other countries for their meat, fat, and oil. Over time, overfishing led to the gradual disappearance of the Long-finned pilot whale in the North Atlantic.

Nowadays the practice no longer has the same importance that once but is still realized in the Faroe Islands. Direct hunting has ceded its position as the leading threat to the species to bycatch, but other dangers menace this cetacean: the contamination of its habitat with chemical substances and heavy metals as well as the strandings that occur when fishing boats lead the Long-finned pilot whale towards the beaches.

The Red List of the International Union for the Conservation of Nature (IUCN) does not have enough data to assess its conservation status. In this regard, the UK Biodiversity Action Plan considers the protection of the species to be of paramount importance, and the Wildlife and Field Act 1981 declares the illegality of its capture, killing or any other activity that could be harmful to the life of whales and dolphins in the waters of the United Kingdom.

Conservation efforts should include ensuring the protection of the species from the entanglement they suffer in several kinds of fishing nets.

References

Mediterranean Marine Mammal Ecology and Conservation. Academic Press, 2016.

William F. Perrin, Bernd Würsig, J.G.M. ‘Hans’ Thewissen. Encyclopedia of Marine Mammals. Academic Press, 2009. Page 847.

http://www.cms.int/reports/small_cetaceans/data/G_melas/g_melas.htm

http://www.fisheries.noaa.gov/pr/species/mammals/whales/long-finned-pilot-whale.html

(Orcinus Orca)

INFORMATION AND CHARACTERISTICS.

Although it is commonly named “killer whale,” environmentalist are trying to change this name because there are two inaccuracies in it: it is not a whale, and much less a killer. The Orca is a toothed cetacean member of the genus Delphinidae, so it is the largest dolphin in the world.

Although it is also a powerful predator that even attacks sharks, it is not a human killer. Attacks have occurred but only from specimens in captivity victims of stress and confusion.

Order: Cetacea
Family: Delphinidae
Genus: Orcinus

HOW DO THEY LOOK? PHYSICAL CHARACTERISTICS.

Orcas are considered monotypic, that is, they belong to a single species although in recent years some scientists think that the smaller orcas of Antarctic waters are a subspecies. There are several ecotypes result of one of the largest distribution of all mammals, in fact, just after humans.

Weight and size.
Orcas exhibit sexual dimorphism since males are larger than females. Adult males reach a length of 6 to 8 meters and weigh about 6 tons; while females have a length about 5-7 meters and weigh about 3 to 4 tons. The maximum registered length in an orca is 9.8 meters.

Morphology.
It is a huge and bulky cetacean that has a shape similar to the other dolphin species. It has a strong skeleton and the skin covered with collagen fibers. Both genders have a round head with a big forehead and pectoral flippers similar to paddles. Its dorsal fin is also large: in males can measure up to 1.8 meters while that of females reaches between 70 and 80 centimeters and is more curved. The caudal fin has two flukes and measures 1.8 meters wide.

It has 10 centimeters long teeth covered with enamel; those in the front can lean forward when the orca holds a prey. Orcas have excellent senses of sight, hearing and touch.

It is the largest mammal predator and feeds on a wide variety of large or small animals.

Skin Coloration.
An Orca is easily recognizable by its black and white color pattern. The dorsal area is black but changes to white from the lower jaw passing through all the ventral part up to the anus. Above the eyes, it has a white patch. Its flippers are also black, and it has a gray saddle patch in the dorsal area just behind the dorsal fin. Orcas show this coloration pattern after one year of age.

Distinctive features.
The color pattern is unique to each specimen. Also, the gray patch behind the dorsal fin called “saddle” got this name because of its apparent resemblance to such supportive structure.

Orcas – Orcinus orca.

WHERE DO THEY LIVE? HABITAT AND DISTRIBUTION.

The orca distribution is incredibly broad, ranging from the polar waters to the equator in the open ocean or closed systems such as the Gulf of Mexico, the Gulf of California, the Persian Gulf, the Mediterranean Sea and the Red Sea. They are distributed in all the oceans of the world although they have a preference for cold regions. They live in waters with depths of 20 to 60 meters, and occasionally there are sightings along the coasts. After humans, killer whales are the most distributed mammals on the Earth.

The list of countries they inhabit is very long but includes:
Canada, France, Greenland, Portugal, Iceland, Ireland, Italy, Oman, Pakistan, India, Vietnam, Yemen, Bangladesh, Benin, Brunei, Cambodia, United Arab Emirates Uruguay, Venezuela, Mexico, Costa Rica, Dominican Republic, Singapore, Saint Vincent and the Grenadines, China, Japan, Philippines, Jamaica, Honduras, Ecuador, Colombia, Antigua and Barbuda, Russia, Papua New Guinea, Madagascar, Haiti and Brazil.

Orcas can inhabit deep or shallow waters as well as visit bays, estuaries, and even rivers. They dwell in all kind of marine aquatic habitats.

WHAT DO THEY EAT? DIET AND EATING HABITS.

It is the largest mammal predator and feeds on a wide variety of large or small species, warm-blooded or cold-blooded, whether dangerous or not. Orcas do not discriminate. A daily intake of 45 kilograms may include seals, sea lions, fishes, squids, turtles, birds (even penguins), sea otters and even animals considered as predators like sharks. Killer whales even prey on baleen whales or dolphins.

When orcas consume small prey, they swallow it completely, but they have to split the large ones into smaller pieces before ingesting them, which usually do it by shaking the victim violently. They have several hunting strategies depending on the type of prey and the region they inhabit. For example, in the North Pacific, they feed on some fish, seabirds, and sharks.

Cooperative hunting is a demonstration of their sociability and their intelligence. First, a group of orcas follow a prey and corner it. When the prey is exhausted, the orcas give the victims powerful blows with their tail before eating them.

Orcas in the wild.

HOW DO THEY REPRODUCE? MATING AND REPRODUCTION.

Killer whales have a polygamous reproduction system, and both genders mate with multiple individuals throughout their life. Females are sexually mature at an age ranging from 6 to ten years, and males between 10 and 13 years. Both can mate at any time of the year although in the northern hemisphere this occurs more frequently during October and March.

After a gestation period of 14-18 months, the mother gives birth to one calf; this happens one time every 3-8 years until the female turns 40 years old. A mother provides dedicated maternal care because the breeding depends entirely on her for feeding and protection. When the calf is 1 or 2 years old, it is weaned but continues in its native pod.

HOW DO THEY BEHAVE? BEHAVIOR.

It is a sociable species with a complex social structure. They live, reproduce and feed in pods of up to 40 or 50 members forming temporal superpods with more members sometimes. In general, these pods have 20 percent of mature males, 20 percent of offspring and 60 percent of females and young males. Orcas always stay in the mother’s group.

In some cases, an elementary unit may consist of a mature female, her adult offspring and the offspring of her daughters. Sometimes, some pods have a small number of members but with no close links.

On the other hand, killer whales can communicate through various sounds that other orcas in the pod recognize even though they are several kilometers away. Jaw claps, pulsed calls, pops, and whistles, are part of their communication sounds as well as echolocation clicks.

WHAT IS THEIR CONSERVATION STATUS? THREATS AND CONSERVATION.

State of conservation: Data deficient.
* But the population of some regions is in danger of extinction.

For centuries, orcas have frequently been hunted for oil and meat. Now, commercial fishing is not a significant hazard, but bycatch is. Also, they are very vulnerable to the contamination of their habitat as nocive chemicals can penetrate their skin and tissues; Consequently, this affects their reproductive and survival capabilities.

While there isn’t an assessment of the conservation status of the entire species, the population of some regions is in danger of extinction, such as that of British Columbia and Washington, in the United States. For this reason, CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora) has included the species in Appendix II of the species whose trade is controlled. The IUCN Red List does not have enough data to establish it in a category.

In 2008, NOAA (National Oceanic and Atmospheric Administration) through the National Marine Fisheries Service announced a Recovery Plan for Southern Resident Orcas to improve the living conditions of these cetaceans.

References

http://www.iucnredlist.org/details/15421/0

http://www.nmfs.noaa.gov/pr/species/mammals/whales/killer-whale.html

William F. Perrin, Bernd Würsig, J.G.M. ‘Hans’ Thewissen. Encyclopedia of Marine Mammals. Academic Press, 2009. Page 650.

Ford, Ellis, Balcomb. Killer Whales: The Natural History and Genealogy of Orcinus Orca in British Columbia and Washington. UBC Press, 2000.

(Lagenodelphis hosei)

 INFORMATION AND CHARACTERISTICS.

It is one of the most recently recognized cetaceans. The Fraser’s dolphin was scientifically described for the first time in 1956 Although the first specimen analyzed was in Borneo in 1895. During the first half of the twentieth century, the knowledge about this species came only from some bones until 1971 when scientist rediscovered the species thanks to the sighting of a live specimen in 1970.

The name of this dolphin is in honor of Francis Fraser, its discoverer in 1956.

Order: Cetacea
Family: Delphinidae
Genus: Lagenodelphis

HOW DO THEY LOOK? PHYSICAL CHARACTERISTICS.

This little-known dolphin is a medium-sized cetacean with a very distinctive appearance.

Weight and size.
The adult male is slightly larger than the female, so there is sexual dimorphism in the species. While females reach a maximum length of 2.6 meters, males can reach up to 2.7 meters in length. It weighs about 200 kilograms.

Morphology.
The Fraser’s dolphin body is robust and fusiform, with a postanal hump and a small beak. The pectoral flippers and the flukes of the caudal fin are triangular and pointy. The dorsal fin located in the middle of the dorsum is small, triangular and slightly curved.

Skin Coloration.
The color pattern of its body is unique to this species although it has a stripe that starts in the eyes and ends towards the anus present in other species. This band is very visible in young specimens, and it gets darker when the dolphin is older. It varies according to the habitat and the gender, and is similar to a raccoon “mask.”

The background color of the skin is bluish gray in the upper dorsal area and white or light pink in the lower ventral region.

Distinctive characteristics.
Along the lower jaw begins another light stripe that extends to the sides of the body.

WHERE DO THEY LIVE? DISTRIBUTION AND HABITAT.

It has a pantropical distribution (tropical regions of all the continents). The Fraser’s dolphin dwells between the latitudes 30° north and 30° south in the Pacific, Atlantic, and Indian oceans but it reaches places outside of its range of distribution in Australia, France, Scotland, and Uruguay, perhaps due to climate change.

It is present in Australia, Thailand, China, Brazil, Costa Rica, Dominica, Ecuador, Senegal, Solomon Islands, Cape Verde, Taiwan, Venezuela, Argentina, Angola, Comoros Islands, Japan, Kiribati, Madagascar, South Africa, Spain, Costa Rica, Oman, Palau, French Polynesia, Panama, Micronesia, Philippines, Sri Lanka and Saint Vincent and the Grenadines.

It inhabits tropical and subtropical waters with depths greater than 1,000 meters in areas near the coasts, or areas of the continental shelf.

WHAT DO THEY EAT? DIET AND EATING HABITS.

Their diet is composed of mesopelagic fish, cuttlefish, squid and shrimp. It prefers to feed in deep areas (250-500 meters deep) and very rarely on the surface, so their food can also be benthic. It always looks for the biggest prey available.

HOW DO THEY REPRODUCE? MATING AND REPRODUCTION.

Both genders reach sexual maturity at about seven years of age, but possibly females can be mature a little earlier. This cetacean is polygamous, and the mothers can give birth once every two years.

Mating appears to occur during the summer months. There is no knowledge about possible courtship processes among the couple. The gestation period lasts between 10 and 12.5 months, after which the female gives birth in spring or summer to a single offspring that measures about 1 meter in length.

The life expectancy of this dolphin is approximately 16 or 17 years although in Japan an individual of 17 years and a half was found.

HOW DO THEY BEHAVE? BEHAVIOR.

It is a marine mammal that shows high sociability. The pods of this dolphin are made of 10 to 100 individuals, and sometimes they create larger groups up to 1,000 dolphins. They have no problem in associating with other species of dolphins or cetaceans, such as the melon-headed whale (Peponocephala electra) and the Short-finned pilot whale (Globicephala macrorhynchus). Seagulls can also associate with this dolphin to feed themselves.

The pods move fast, and a single Fraser’s dolphin swims in a manner described as “ostentatious” and “aggressive,” leaving a trail of foam in its wake. Pods seldom follow boats and may be timid and playful although in some areas they prove to be more accessible.

WHAT IS THEIR CONSERVATION STATUS? THREATS AND CONSERVATION.

Conservation Status: “Least Concern.”

This species has a conservation status as “Least Concern” on the Red List of the International Union for the Conservation of Nature (IUCN). However, it continually faces the danger of bycatch. In the eastern Pacific Ocean, this dolphin often gets entangled in nets targeting tuna, but in regions near the Philippines, more than 800 dolphins are captured annually to use their meat or as bait for other species.

This dolphin does not have any known natural predator, but some think that killer whales and sharks can attack them, as in the case of other cetaceans.

Despite the threats, Fraser’s dolphins are still abundant in their range of distribution. There are no specific research or conservation strategies, but the species is in Appendix II of CITES, in the group of species which its commercial fishing requires control.

References

http://www.iucnredlist.org/details/11140/0

http://www.cms.int/reports/small_cetaceans/data/L_hosei/L_hosei.htm

http://www.nmfs.noaa.gov/pr/species/mammals/cetaceans/frasersdolphin.htm

https://en.wikipedia.org/wiki/Fraser%27s_dolphin

]]> https://www.dolphins-world.com/pilot-whale/ Thu, 27 Apr 2017 05:27:30 +0000 http://www.dolphins-world.com/?p=100 Pilot Whale Facts

Globicephala macrorhynchus

INFORMATION AND CHARACTERISTICS.

The Short-finned pilot whale is the name of the second largest species of dolphin, only surpassed by the orca (Orcinus orca).

Order: Cetacea
Family: Delphinidae
Genus: Globicephala

HOW DO THEY LOOK? PHYSICAL CHARACTERISTICS.

This species is commonly called whale, without being one, because of its large size and its behavior similar to that of whales. It has the following characteristics:

Morphology.
From the body of the Short-finned pilot whale stands out a bulbous head, big and prominent that in the male is more notorious and in some old individuals hangs slightly above the mouth. The beak is missing from the head, and instead, it has a short snout. It has short pectoral fins and a sickle-shaped dorsal fin located near the head.

Weight and size.
Males are longer and heavier than females, so sexual dimorphism is present in the species. It measures about 5.5 meters while the opposite sex reaches a length of 3.7 meters. The weight of adults is 1,000-3,000 kilograms.

Skin Coloration.
Its skin has a dark gray or black color in most parts which contrast with a light gray or white stripes on the chest and neck. In the bottom of the chin, there is a light patch with anchor shape. Above the eye, it has a stripe running down the dorsum and extending backward from the dorsal fin. A white or light gray patch with a saddle shape is behind its dorsal fin.

Distinctive characteristics.
It is very similar to the Long-finned pilot whale and is often confused. The difference between them lies in the length of the pectoral flippers, which in this case are smaller.

WHERE DO THEY LIVE? DISTRIBUTION AND HABITAT.

It inhabits tropical, subtropical and warm waters of the world. Native to the Atlantic, Pacific, and Indian oceans, it does not venture beyond the latitudes 50° North and 40° South. Many individuals dwell in areas north of the Atlantic Ocean, the Western Pacific and the southern hemisphere.

There are populations from the Gulf of Alaska to Guatemala, from Eastern Europe to Africa, the Sea of ​​Japan, the Red Sea, Hawaii and the Strait of Gibraltar.

It is common in deep offshore areas near the continental shelf or deep underwater canyons. Sometimes it reaches coastal regions. It inhabits at waters with depths of 600-1,000 meters.

WHAT DO THEY EAT? DIET AND EATING HABITS.

The primary food of the Short-finned pilot whale is not precisely fish, but cephalopods, mostly octopus, and squid. The 45 kilograms of food they eat per day also contain some small fish species and probably other marine mammals. Surprisingly, this cetacean sometimes chases sperm whales and other dolphins, although there is not conclusive evidence that is hunting them, it is thought to consume warm-blooded animals.

Their favorite feeding species are the following:
– Cape Hope squid (Loligo reynaudii).
– “Wonderful Lamp” squid (Lycoteuthis).
– European flying squid (Todarodes sagittatus).
– Squid (Eucleoteuthis luminosa).
– California market squid (Loligo opalescens).
– Neon flying squid (Ommastrephes bartrami).
– Giant Pacific Octopus (Enteroctopus dofleini).
– Glass squid of the genus Cranchia.

This dolphin looks for food at dawn and dusk. When it is time, it does very deep dives, of more than 600 meters, and can travel more than 1 kilometer of distance between its starting point and the final zone of feeding.

In this regard, the availability of prey occasionally makes them perform coastal movements and change their habits. Their dives relate with the ascension of their usual benthic prey to the upper water column. Another clear example: when the squid comes to spawn near the coasts, the calderón follows the trail and also resides there for a short time.

HOW DO THEY BEHAVE? BEHAVIOR.

It is a social animal that gathers in pods composed of 10-60 members and sometimes hundreds and usually is not alone. The base of its society is the group of females with their offspring, and from them, the non-breeding females are considered a “database” that stores information about the pod.

In any case, the bonds between individuals are very close and intense, similar to that of the long-finned pilot whales (Globicephala melas). Cooperation is essential in the group, and even a female can provide care for a calf that is not her own.

It is mainly nocturnal and relegates its rest and its travels to the day. While there is no sun, it dives to hunt and socialize with its mates.

It always travels from one place to another, but there is no information about the migration patterns that follows. The short-finned pilot whale goes to other locations depending on the movements of its prey or the changes in water temperature.

HOW DO THEY REPRODUCE? MATING AND REPRODUCTION.

The Short-finned pilot whale is polygamous. There is one male for every eight mature females which facilitates the mating opportunity to the former, but also the females mate with multiple males throughout their life. The interval between each delivery is 5-8 years.

The female matures between 7 and 12 years of age and the male between 7 and 17 years. However, the average maturation age of female and male is 9 and 14.6 years, respectively. The existence of a defined breeding season is unknown, but they can reproduce at any time of the year although most births occur during the spring, autumn and winter months.

Males join different pods and manage to mate with a female. Once it is pregnant, it moves to the group of mothers with calves and waits for 15 months the birth of its offspring. The calf receives care from its mother and other females of the pod and is weaned at about two years old.

During its lifetime, a female has 4 or 5 offspring, until she is about 40 years old. The last offspring of a female can feed with breast milk from the mother for up to 15 years!

WHAT IS THEIR CONSERVATION STATUS? THREATS AND CONSERVATION.

Conservation Status: “Data Deficient.”

In Japan, they eat several dishes prepared with Short-finned pilot whales.

The Short-finned pilot whale is in danger as a result of bycatch with gillnets, trawls and longlines, collisions with boats of any type, massive strandings and loud sounds that disturb their environment.

It is necessary to emphasize that humans have much responsibility for the deaths of these cetaceans. In Japan, the large number of catches are because the Short-finned pilot whale, like other cetaceans, is consumed in various Asian dishes.

This dolphin has a conservation status of “Data Deficient” on the Red List od the International Union for the Conservation of Nature. The Pacific Offshore Cetacean Take Reduction Plan implemented by the NMFS (National Marine Fisheries Service) regulates the use of fishing devices to reduce the numbers of deaths caused by the incidental catch of these dolphins.

References

http://www.iucnredlist.org/details/9249/0

http://www.cms.int/reports/small_cetaceans/data/G_macrorhynchus/g_macrorhynchus.htm

http://animaldiversity.org/accounts/Globicephala_macrorhynchus/

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