Globicephala Lesson 1828

Qrind (lat. Globicephala) — Delfinlər sinfinə daxil olan heyvan cinsi. Cinsə iki növ daxildir: Adi qrind (Globicephala melas) və Qısaüzgəc qrind (Globicephala macrorhynchus). «Qrind» sözü Farer dilindən götürülmüşdür.

Xüsusiyyət

Qrindlərin uzunluqları 3,6 - 8,5 metr arasında dəyişir. Çəkiləri 800 kq olsada bəzən 3 tonu keçə bilir. Ağ ləkələr istisna demək olar ki, qara rəngdə olur. Hər iki növ bir birindən əsasən üzgəclərinə görə fərqlənirlər. Qısaüzgəc qrindlərdə hər çənədə 14-18 diş, Adi qrindlərdə isə hər çənədə 16-26 arası diş olur. Osa və Qısaüzgəc qrindlər nadir məməlilərdəndir ki (insanda daxil), dişiləri Menopauza dövrü keçirir və bu uzun on illiklər boyu təkrarlanır^[1][2].

Qrindlər açıq dəniz sahələrini xoşlayırlar və nadir hallarda sahilə yaxınlaşırlar. Qısaüzgəc qrindlər tropik, subtropik qurşaqların dənizlərində yayılmışlar. Adi qrindlər isə hətta Şimali Avropaya belə yayıla bilirlır.

5-10 dəqiqə sualtında qala bilirlər. 600 metr sualtına enirlər. Başıayaqlılar və balıqlarla qidalanırlar. Onların Kaşalotlara hücumu müşahidə edilmişdir^[3]. Qrindlər 20 başdan ibarət qruplarda birləşirlər. Bəzən qruplarda delfinlərin sayı 100-ə çatır.

Qrindlərin insanlara hücumu yalnız bir halda müşahidə edilmişdir. 12 may 1991-ci ildə qrind Lizu Kastellonun ayağından yapışaraq onu 10 metr dərinliyə aparmışdır. Sonradan isə qadını suyun səthinə çıxarmışdır. Qadın yalız kiçik zədələrlə qurtulmuşdur. Delfin onu yemək istəməmişdir. Hadisə onu deməyə əsas verir ki, vəhşi canlılarla ehtiyatlı olmaq lazımdır^[4].

Şəkilləri

• İnsana olan nisbəti

• Qrind qrupu

• Qrindlər

• Qrind

Ədəbiyyat

• Ronald M. Nowak: Walker’s Mammals of the World. Johns Hopkins University Press 1999, ISBN 0-8018-5789-9

İstinadlar

1. ↑ Bowden, D.M.; Williams, D.D. (1985). "Aging". Adv.Vet.Sci.Comp.Med. 28: 306–341.
2. ↑ Physiological Basis of Aging and Geriatrics, Fourth Edition, Paola S. Timiras, CRC Press, 2013, page 161
3. ↑ Serial «BBC: Dəniz nəhəngləri», 3-cü bölüm
4. ↑ видео

Els caps d'olla negres (Globicephala) són un gènere de dues espècies de cetacis. El gènere forma part de la família dels delfínids, o dofins oceànics, tot i que el seu comportament s'assembla més al de les balenes, més grans. Les dues espècies són el cap d'olla negre d'aleta llarga (G. melas) i el cap d'olla negre d'aleta curta (G. macrorhynchus). Les dues espècies costen de distingir a alta mar.

Característiques

Les dues espècies del gènere són delfínids de grans dimensions (de 5 a 7 metres de longitud i d'1 a 3 tones de pes), que es caracteritzen pel seu front bombat i per la presència de l'òrgan anomenat meló. Globicephala melas es distingeix pel seu cap gros, per la seva aleta dorsal ganxuda i pel seu color negre. Animal molt gregari, formant grans grups amb dofins i altres cetacis. Qualsevol objecte, per exemple el cadàver d'un rorqual o un banc de peixos, pot concentrar-los en gran nombre. L'altre cap d'olla negre és més petit i té les aletes més curtes. Ambdues espècies estan catalogades a la Llista Vermella de la UICN com a espècies amb dades insuficients per establir el risc.

Taxonomia

• G. macrorhynchus
• G. melas

Referències

• Wilson, Don; Reeder, DeeAnn, eds (2005). Mammal Species of the World (3a edició). Baltimore: Johns Hopkins University Press, 2 vols. (2142 pp.). ISBN 978-0-8018-8221-0. http://www.bucknell.edu/msw3/browse.asp?id=14300050.

Enllaços externs

En altres projectes de Wikimedia: Commons Viquiespècies

• Globicephala (como Globicephalus) a "Fauna ibèrica; mamífers". Ángel Cabrera Latorre. Any 1914. Facsímil electrònic.

Viccionari

Grindehvaler (Globicephala) er en slægt i familien delfiner med to arter, langluffet og kortluffet grindehval. De to arter er svære at adskille til havs, og undersøgelse af kraniet er den bedste måde til artsbestemmelse.^[1] Til sammen er de to arter udbredt over næsten hele Jorden, med de langluffede grindehvaler i koldere egne end de kortluffede, der lever i tropiske og subtropiske havområder. Grindehvaler er blandt de største i delfinfamilien, kun overgået af spækhuggeren.

Grindehvaler lever primært af blæksprutter, men også af fisk. De er meget sociale og undersøgelser tyder på, at både hanner og hunner forbliver i samme flok hele livet, hvilket er usædvanligt blandt pattedyr.^[2] Hanner forlader kun midlertidigt flokken for at parre sig med hunner fra andre flokke.^[3] Grindehvaler er kendt for deres strandinger.

Kilder

Die Grindwale oder Pilotwale (Globicephala) im engeren Sinn sind eine Walgattung aus der Familie der Delfine (Delphinidae) mit zwei Arten, dem

• Gewöhnlichen oder Langflossen-Grindwal (Globicephala melas) und dem
• Kurzflossen-Grindwal (Globicephala macrorhynchus).

Im weiteren Sinn werden mehrere kurzschnäuzige Delfinarten (wie der Zwerggrindwal, der Rundkopfdelfin und der Breitschnabeldelfin) unter dieser Bezeichnung zusammengefasst. Die Bezeichnung grind stammt aus dem Färöischen.

Merkmale

Grindwale erreichen eine Länge von 3,6 bis 8,5 Metern und ein Gewicht von durchschnittlich 800 Kilogramm (in Ausnahmefällen bis zu knapp 3000 Kilogramm). Der Körper ist zylindrisch, der wie eine Kugel geformte Kopf kaum vom Rumpf abgesetzt, die Melone überragt die sehr kurze Schnauze der Tiere. Mit Ausnahme eines weißen Flecks unterhalb des Kinns sind sie schwarz gefärbt. Die beiden Arten unterscheiden sich in der namensgebenden Länge der Flipper sowie in der Anzahl der Zähne – Kurzflossen-Grindwale haben sieben bis neun Zähne pro Kieferhälfte und damit weniger als der Gewöhnliche Grindwal (8 bis 13 pro Kieferhälfte).

Lebensweise

Grindwale bevorzugen das offene Meer und sind nur selten in Küstennähe zu finden. Während der Kurzflossen-Grindwal tropische und subtropische Meere bevorzugt, ist der Gewöhnliche Grindwal häufiger in gemäßigten und kühlen Regionen anzutreffen, so auch in europäischen Gewässern.

Grindwale schlafen am Tag und gehen in der Nacht auf Nahrungssuche. Ihre Tauchgänge sind 5 bis 10 Minuten lang, dabei erreichen sie Tiefen von bis zu 600 Metern. Ihre Nahrung setzt sich vorwiegend aus Kopffüßern zusammen, in geringem Ausmaß erbeuten sie auch Fische. Diese Tiere leben in Gruppen (Schulen) von durchschnittlich 20 Tieren. Eine Schule folgt einem Leittier, daher der Name Pilotwale. Das Sozialverhalten dieser Tiere ist hoch entwickelt.

Systematik

Delphinidae

andere Delphinidae

Orcaella

Globicephalinae

Rundkopfdelfin (Grampus griseus)

Kleiner Schwertwal (Pseudorca crassidens)

Zwerggrindwal (Feresa attenuata)

Breitschnabeldelfin (Peponocephala electra)

Grindwale (Globicephala)

Kurzschnauzendelfine (Lagenorhynchus)

Schwarz-Weiß-Delfine (Cephalorhynchus)

Großer Schwertwal (Orcinus orca)

Vorlage:Klade/Wartung/Style

Genetische Untersuchungen zeigen die Grindwale als Schwestergruppe zu einem Taxon aus Zwerggrindwal (Feresa attenuata) und Breitschnabeldelfin (Peponocephala electra).^[1] Gemeinsam bilden diese Arten mit dem Kleinen Schwertwal (Pseudorca crassidens) und dem Rundkopfdelfin (Grampus griseus) die Unterfamilie Globicephalinae innerhalb der Delfine und werden den beiden Arten der Gattung Orcaella gegenübergestellt.^[1]

Belege

1. ↑ ^{a b c} José L. Horreo: New insights into the phylogenetic relationships among the oceanic dolphins (Cetacea: Delphinidae). Journal of Zoological Systematics and Evolutionary Research 57 (2), Mai 2019; S. 476–480. doi:10.1111/jzs.12255

Literatur

• Ronald M. Nowak: Walker's Mammals of the World. Johns Hopkins University Press 1999, ISBN 0-8018-5789-9

Weblinks

Grindahvalurin er eitt av størstu djórunum í springarafamiljuni. Hann er ein ímynd av føroyskari mentan og hevur hjálpt føroyingum at yvirliva í fleiri øldir. Grindahvalir liva í familjubólkum, sum eru samansettir av honum, ungum teirra og av eldri hvalum. Ein vanligur bólkur hevur næstan 70% hondjór, og fyri at sleppa undan innannøring makast hesar bert við hannum úr øðrum bólkum. Líknandi familjubólkar, har honirnar hava avgerandi leiklutin, eru óvanligir í djóraheiminum.

Grindahvalur er ikki friðaður. Einstakar grindir verða dripnir í Grønlandi, men annars verður grindahvalur nú á døgum bara hildin til í Føroyum.

Sí eisini

• Grindadráp

Lodan Pilot ya iku cetaceans sing kalebu génus Globicephala. Loro spésies sing isih urip ya iku lodan pilot akèpèt dawa (G. melas) lan cendhak (G. macrorhynchus). Leloroné angèl dibedakaké nalika ana ing segara mula analisis sing paling apik kanggo mbédakaké kaloroné ya iku analisis cumplung. Lodan Pilot akèpèt dawa urip ing segara sing luwih atis lan lodan pilot akèpèt cendhak urip ing segara tropikal lan subtropikall. Kéwan iki kapitung lodan gedhé dhéwé ing jinis lumba-lumba segara, sing luwih gedhé manèh ya iku lodan pangisas. Lodan pilot lan lumba-lumba gedhé liyané asring disebat blackfish.

Lodan pilot mligi makan iwak nus, lan uga iwak. Lodan iki kalebu kéwan sing sosial banget, lan ana kajian sing mratélakaké manawa lodan lanang lan wadon panggah ing sak baboné, sipat sing ora lumrah ing antarané mamalia, nanging uga tinemu ing kumpulan lodan pangisas. Lodan pilot akèpèt cendhak iku salah siji spésies mamalia sing wadoné nemahi luwas getih, lan kéwan wadon sing ngliwati mangsa réproduktif bisa nyengkuyung uripé lodan enom ing njero saké. Kéwan iki kaciri saka patrapané sing seneng ngandhasaké awaké ning pasisir saéngga kéwan iki dadi salah siji cetacean sing seneng ngandhasaké. Sawetara téyori wis diserat saperlu ngandharaké patrapan iki. Status konservasi spésies iki durung ditemtokaké, nanging kéwan iki dadi bedhagané para pedhagan. Pedhagan lodan ing sawenèh nagara terus mbedhag lodan pilot iki.

Тоголок баштар (лат. Globicephala) — делфиндердин бир уруусу, буларга төмөнкү түрлөр кирет: кадимки тоголок баш (лат. G. melaena), чоң тумшук тоголок баш (G. macrorhynchus), кара тоголок баш (G. seammoni).

Колдонулган адабияттар

• А. А. Алдашев. Биология терминдеринин жана айбанат аттарынын орусча-кыргызча сөздүгү. - Бишкек, 1998. ISBN 9967-11-027-9

Pilot whales are cetaceans belonging to the genus Globicephala. The two extant species are the long-finned pilot whale (G. melas) and the short-finned pilot whale (G. macrorhynchus). The two are not readily distinguishable at sea, and analysis of the skulls is the best way to distinguish between the species. Between the two species, they range nearly worldwide, with long-finned pilot whales living in colder waters and short-finned pilot whales living in tropical and subtropical waters. Pilot whales are among the largest of the oceanic dolphins, exceeded in size only by the orca. They and other large members of the dolphin family are also known as blackfish.

Pilot whales feed primarily on squid, but will also hunt large demersal fish such as cod and turbot. They are highly social and may remain with their birth pod throughout their lifetime. Short-finned pilot whales are one of the few mammal species in which females go through menopause, and postreproductive females continue to contribute to their pod. Pilot whales are notorious for stranding themselves on beaches, but the reason behind this is not fully understood, although marine biologists have shed light on the discovery it is due to the mammals inner ear (their principal navigational sonar) being damaged from noise-pollution in the ocean, such as from cargo ships or military exercises.^[2] The conservation status of short-finned and long-finned pilot whales has been determined to be least concern.

Naming

The animals were named "pilot whales" because pods were believed to be "piloted" by a leader.^[3][4] They are also called "pothead whales" and "blackfish". The genus name is a combination of the Latin word globus ("round ball" or "globe") and the Greek word Kephale ("head").^[3][4]

Taxonomy and evolution

Pilot whales are classified into two species; the long-finned pilot whale (Globicephala melas) and the short-finned pilot whale (G. macrorhynchus) The short-finned pilot whale was described, from skeletal materials only, by John Edward Gray in 1846. He presumed from the skeleton that the whale had a large beak. The long-finned pilot whale was first classified by Thomas Stewart Traill in 1809 as Delphinus melas.^[5] Its scientific name was eventually changed to Globicephala melaena. Since 1986, the specific name of the long-finned pilot whale was changed to its original form melas.^[6] Other species classifications have been proposed but only two have been accepted.^[7] There exist geographic forms of short-finned pilot whales off the east coast of Japan,^[8] which comprise genetically isolated stocks.^[9]

Fossils of an extinct relative, Globicephala baereckeii, have been found in Pleistocene deposits in Florida.^[3] Another Globicephala dolphin was discovered in Pliocene strata in Tuscany, Italy, and was named G. etruriae.^[3] Evolution of Tappanaga, the endemic, larger form of short-finned pilots found in northern Japan, with similar characteristics to the whales found along Vancouver Island and northern USA coasts,^[10] have been indicated that the geniture of this form could be caused by the extinction of long-finned pilots in north Pacific in the 12th century where Magondou, the smaller, southern type possibly filled the former niches of long-finned pilots, adapting and colonizing into colder waters.^[11]

Description

Pilot whales are mostly dark grey, brown, or black, but have some light areas such as a grey saddle patch behind the dorsal fin.^[4] Other light areas are an anchor-shaped patch under the chin, a faint blaze marking behind the eye, a large marking on the belly, and a genital patch.^[4] The dorsal fin is set forward on the back and sweeps backwards. A pilot whale is more robust than most dolphins, and has a distinctive large, bulbous melon.^[4] Pilot whales' long, sickle-shaped flippers and tail stocks are flattened from side to side.^[4] Male long-finned pilot whales develop more circular melons than females,^[4] although this does not seem to be the case for short-finned pilot whales off the Pacific coast of Japan.^[12]

Long-finned and short-finned pilot whales are so similar, it is difficult to tell the two species apart.^[3] They were traditionally differentiated by the length of the pectoral flippers relative to total body length and the number of teeth.^[7] The long-finned pilot whale was thought to have 9–12 teeth in each row and flippers one-fifth of total body length, compared to the short-finned pilot whale with its 7–9 teeth in each row and flippers one-sixth of total body length.^[4] Studies of whales in the Atlantic showed much overlap in these characteristics between the species, making them clines instead of distinctive features.^[4] Thus, biologists have since used skull differences to distinguish the two species.^[3][4]

The size and weight depend on the species, as long-finned pilot whales are generally larger than short-finned pilot whales.^[12][13] Their lifespans are about 45 years in males and 60 years in females for both species. Both species exhibit sexual dimorphism. Adult long-finned pilot whales reach a body length of approximately 6.5 m, with males being 1 m longer than females.^[14] Their body mass reaches up to 1,300 kg in females and up to 2,300 kg in males.^[15] For short-finned pilot whales, adult females reach a body length of about 5.5 m, while males reach 7.2 m and may weigh up to 3,200 kg.^[15]

Distribution and habitat

Pilot whales can be found in oceans nearly worldwide, but data about current population sizes is deficient. The long-finned pilot whale prefers slightly cooler waters than the short-finned, and is divided into two populations. The smaller group is found in a circumpolar band in the Southern Ocean from about 20 to 65°S. It may be sighted off the coasts of Chile, Argentina, South Africa, Australia, and New Zealand.^[16] An estimated more than 200,000 individuals were in this population in 2006. The second, much larger, population inhabits the North Atlantic Ocean, in a band from South Carolina in the United States across to the Azores and Morocco at its southern edge and from Newfoundland to Greenland, Iceland, and northern Norway at its northern limit. This population was estimated at 778,000 individuals in 1989. It is also present in the western half of the Mediterranean Sea.^[16]

The short-finned pilot whale is less populous. It is found in temperate and tropical waters of the Indian, Atlantic and Pacific Oceans.^[17] Its population overlaps slightly with the long-finned pilot whale in the temperate waters of the North Atlantic and Southern Oceans.^[3] About 150,000 individuals are found in the eastern tropical Pacific Ocean. More than 30,000 animals are estimated in the western Pacific, off the coast of Japan. Pilot whales are generally nomadic, but some populations stay year-round in places such as Hawaii and parts of California.^[3] They prefer the waters of the shelf break and slope.^[3] Once commonly seen off of Southern California, short-finned pilot whales disappeared from the area after a strong El Niño year in the early 1980s, according to the National Oceanic and Atmospheric Administration.^[18] In October 2014, crew and passengers on several boats spotted a pod of 50–200 off Dana Point, California.^[18]

Behavior and life history

Foraging and parasites

Although pilot whales are not known to have many predators, possible threats come from humans and killer whales. Both species eat primarily squid.^[19] The whales make seasonal inshore and offshore movements in response to the dispersal of their prey.^[3] Fish that are consumed include Atlantic cod, Greenland turbot, Atlantic mackerel, Atlantic herring, hake, and spiny dogfish in the northwest Atlantic.^[3] In the Faroe Islands, whales mostly eat squid, but will also eat fish species such as greater argentine and blue whiting. However, Faroe whales do not seem to feed on cod, herring, or mackerel even when they are abundant.^[20]

Pilot whales generally take several breaths before diving for a few minutes. Feeding dives may last over ten minutes. They are capable of diving to depths of 600 meters, but most dives are to a depth of 30–60 m. Shallow dives tend to take place during the day, while deeper ones take place at night. When making deep dives, pilot whales often make fast sprints to catch fast-moving prey such as squid.^[21] Compared to sperm whales and beaked whales, foraging short-finned pilot whales are more energetic at the same depth. When they reach the end of their dives, pilot whales will sprint, possibly to catch prey, and then make a few buzzes.^[21] This is unusual considering deep-diving, breath-holding animals would be expected to swim slowly to conserve oxygen. The animal's high metabolism possibly allows it to sprint at deep depths, which would also give it shorter diving periods than some other marine mammals.^[21] This may also be the case for long-finned pilot whales.^[22]

Pilot whales are often infested with whale lice, cestodes, and nematodes.^[4] They also can be hosts to various pathogenic bacteria and viruses, such as Streptococcus, Pseudomonas, Escherichia, Staphylococcus, and influenza.^[4] One sample of Newfoundland pilot whales found the most common illness was an upper respiratory tract infection.^[23]

Social structure

Both species live in groups of 10–30, but some groups may number 100 or more. Data suggest the social structures of pilot whale pods are similar to those of "resident" killer whales. The pods are highly stable and the members have close matrilineal relationships.^[3] Pod members are of various age and sex classes, although adult females tend to outnumber adult males. They have been observed making various kin-directed behaviors, such as providing food.^[24] Numerous pods will temporarily gather, perhaps to allow individuals from different pods to interact and mate,^[4] as well as provide protection.^[13]

Both species are loosely polygynous.^[13] Data suggest both males and females remain in their mother's pod for life; despite this, inbreeding within a pod does not seem to occur.^[4] During aggregations, males will temporarily leave their pods to mate with females from other pods.^[25] Male reproductive dominance or competition for mates does not seem to exist.^[26] After mating, a male pilot whale usually spends only a few months with a female, and an individual may sire several offspring in the same pod.^[27] Males return to their own pods when the aggregations disband, and their presence may contribute to the survival of the other pod members.^[25] No evidence of "bachelor" groups has been found.^[13][25]

Pilot whale pods off southern California have been observed in three different groups: traveling/hunting groups, feeding groups and loafing groups.^[28] In traveling/hunting groups, individuals position themselves in chorus lines stretching two miles long, with only a few whales underneath.^[29] Sexual and age-class segregation apparently occurs in these groups.^[28] In feeding groups, individuals are very loosely associated, but may move in the same direction.^[28] In loafing groups, whales number between 12 and 30 individuals resting. Mating and other behaviors may take place.^[28]

Reproduction and lifecycle

Pilot whales have one of the longest birth intervals of the cetaceans,^[3] calving once every three to five years. Most matings and calvings occur during the summer for long-finned pilot whales.^[30] For short-finned pilot whales of the Southern Hemisphere, births are at their highest in spring and autumn, while in Northern Hemisphere, the time in which calving peaks can vary by population.^[30] For long-finned pilot whales, gestation lasts 12–16 months, and short-finned pilot whales have a 15-month gestation period.^[3]

The calf nurses for 36–42 months, allowing for extensive mother-calf bonds.^[3] Young pilot whales will take milk until as old as 13–15 years of age. Short-finned pilot whale females will go through menopause,^[31] but this is not as common in females of long-finned pilot whales.^[32] Postreproductive females possibly play important roles in the survival of the young.^[24][33] Postreproductive females will continue to lactate and nurse young. Since they can no longer bear young of their own, these females invest in the current young, allowing them to feed even though they are not their own.^[3] Short-finned pilot whales grow more slowly than long-finned pilot whales. For the short-finned pilot whale, females become sexually mature at 9 years old and males at about 13–16 years.^[3] For the long-finned pilot whale, females reach maturity at around eight years and males at around 12 years.^[3]

Vocalizations

Pilot whales emit echolocation clicks for foraging and whistles and burst pulses as social signals (e.g. to keep contact with members of their pod). With active behavior, vocalizations are more complex, while less-active behavior is accompanied by simple vocalizations. Differences have been found in the calls of the two species.^[34] Compared with short-finned pilot whales, long-finned pilot whales have relatively low-frequency calls with narrow frequency ranges.^[34] In one study of North Atlantic long-finned pilot whales, certain vocalizations were heard to accompany certain behaviors.^[35] When resting or "milling", simple whistles are emitted.^[35] Surfacing behavior is accompanied by more complex whistles and pulsed sounds.^[35] The number of whistles made increases with the number of subgroups and the distance in which the whales are spread apart.^[35]

A study of short-finned pilot whales off the southwest coast of Tenerife in the Canary Islands has found the members of a pod maintained contact with each other through call repertoires unique to their pod.^[36] A later study found, when foraging at around 800 m deep, short-finned pilot whales make tonal calls.^[37] The number and length of the calls seem to decrease with depth despite being farther away from conspecifics at the surface. As such, the surrounding water pressure affects the energy of the calls, but it does not appear to affect the frequency levels.^[37]

When in stressful situations, pilot whales produce "shrills" or "plaintive cries", which are variations of their whistles.^[38] To elude predators, long-finned pilot whales off the southern coast of Australia have been observed to mimic the calls of orcas while scavenging for food. This behaviour is thought to deter orca pods from approaching the pilot whales.^[39]

Antagonistic interactions with other species

Pilot whales have been occasionally observed mobbing or chasing other species of cetaceans. In several parts of the world, including off Iceland, long-finned pilot whales have been frequently documented chasing killer whales.^[40] The reasons for these chases are unknown, but it has been proposed that they might be due to either competition for prey or an anti-predation strategy. In 2021 an adult female killer whale with a newborn pilot whale travelling alongside her was observed off Western Iceland, leading scientists to question whether the relationship between these species might be far more complex than previously suggested.^[41] It is not known whether the newborn was adopted or abducted, but this same female killer whale was seen a year later interacting with a larger group of pilot whales.

Stranding

Of the cetaceans, pilot whales are among the most common stranders.^[42] Because of their strong social bonds, whole groups of pilot whales will strand. Single stranders have been recorded and these are usually diseased.^[3] Group stranding tends to be of mostly healthy individuals. Several hypotheses have been proposed to explain group strandings.^[3] When using magnetic fields for navigation, the whales have been suggested to get perplexed by geomagnetic anomalies or they may be following a sick member of their group that got stranded.^[3] The pod also may be following a member of high importance that got stranded and a secondary social response makes them keep returning.^[4] Researchers from New Zealand have successfully used secondary social responses to keep a stranding pod of long-finned pilot whales from returning to the beach.^[43] In addition, the young members of the pod were taken offshore to buoys, and their distress calls lured the older whales back out to sea.^[43]

In September 2022, nearly 200 pilot whales died after becoming stranded on Ocean Beach, part of Tasmania's west coast. Authorities said only about 35 survived of the 230 that were stranded.^[44]

Human interaction

The IUCN lists long-finned pilot whales as "least concern" in the Red List of Threatened Species. Long-finned pilot whales in the North and Baltic Seas are listed in Appendix II of the Convention on the Conservation of Migratory Species of Wild Animals (CMS). Those from northwest and northeast Atlantic may also need to be included to Appendix II of CMS.^[16] The short-finned pilot whale is listed on Appendix II of CITES.^[17]

Hunting

The long-finned pilot whale has traditionally been hunted by "driving", which involves many hunters and boats gathering in a semicircle behind a pod of whales close to shore, and slowly driving them towards a bay, where they become stranded and are then slaughtered. This practice was common in both the 19th and 20th centuries. The whales were hunted for bone, meat, oil, and fertilizer. In the Faroe Islands, pilot whale hunting started at least in the 16th century,^[4] and continued into modern times, with thousands being killed during the 1970s and 1980s.^[45][46] In other parts of the North Atlantic, such as Norway, West Greenland, Ireland and Cape Cod, pilot whales have also been hunted, but to a lesser extent.^[47][48] One fishery at Cape Cod harvested 2,000–3,000 whales per year during the late 19th and early 20th centuries.^[49] Newfoundland's long-finned pilot whale fishery was at its highest in 1956, but declined shortly after^[45] and is now defunct. In the Southern Hemisphere, exploitation of long-finned pilot whales has been sporadic and low.^[45] Currently, long-finned pilot whales are only hunted at the Faroe Islands and Greenland.^[16]

According to the IUCN the harvesting of this species for food in the Faroe Islands and Greenland has not resulted in any detectable declines in abundance.^[50]

The short-finned pilot whale has also been hunted for many centuries, particularly by Japanese whalers. Between 1948 and 1980, hundreds of whales were exploited at Hokkaido and Sanriku in the north and Taiji, Izu, and Okinawa in the south.^[13] These fisheries were at their highest in the late 1940s and early 1950s;^[13] 2,326 short-finned pilot whales were harvested in the mid- to late 1980s.^[17] This had decreased to about 400 per year by the 1990s.

Pilot whales have also fallen victim to bycatches. In one year, around 30 short-finned pilot whales were caught by the squid round-haul fishery in southern California.^[51] Likewise, California's drift gill net fishery took around 20 whales a year in the mid-1990s.^[4] In 1988, 141 whales caught on the east coast of the U.S. were taken by the foreign Atlantic mackerel fishery, which forced it to be shut down.^[4]

Pollution

As with other marine mammals, pilot whales are susceptible to certain pollutants. Off the Faroes, France, the UK, and the eastern US, pilot whales were found to have been contaminated with high amounts of DDT and PCB.^[4] Pollutants such as DDT and mercury can be passed from mothers to their babies during gestation and lactation.^[52] The Faroes whales have also been contaminated with cadmium and mercury.^[53] However, pilot whales from Newfoundland and Tasmania were found to have had very low levels of DDT.^[4] Short-finned pilot whales off the west coast of the US have had high amounts of DDT and PCB in contrast to the low amounts found in whales from Japan and the Antilles.^[4]

Cuisine

Pilot whale meat is available for consumption in very few areas of Japan, mainly along the central Pacific coast, and also in other areas of the world, such as the Faroe Islands. The meat is high in protein (higher than beef) and low in fat.^[54] Because a whale's fat is contained in the layer of blubber beneath the skin, and the muscle is high in myoglobin, the meat is a dark shade of red.^[54][55] In Japan, where pilot whale meat can be found in certain restaurants and izakayas, the meat is sometimes served raw, as sashimi, but just as often pilot whale steaks are marinated, cut into small chunks, and grilled.^[55] When grilled, the meat is slightly flaky and quite flavorful, somewhat gamey, though similar to a quality cut of beef, with distinct yet subtle undertones recalling its marine origin.^[54][55][56]

In both Japan and the Faroe Islands, the meat is contaminated with mercury and cadmium, causing a health risk for those who frequently eat it, especially children and pregnant women.^[57] In November 2008, an article in New Scientist reported that research done on the Faroe Islands resulted in two chief medical officers recommending against the consumption of pilot whale meat, considering it to be too toxic.^[58] In 2008, the local authorities recommended that pilot whale meat should no longer be eaten due to the contamination. This has resulted in reduced consumption, according to a senior Faroese health official.^[59]

Captivity

Pilot whales, mostly short-finned pilot whales, have been kept in captivity in various marine parks, arguably starting in the late 1940s.^[60] Since 1973, some long-finned pilot whales from New England waters were taken and temporarily kept in captivity.^[61] Short-finned pilot whales off southern California, Hawaii and Japan have been kept in aquariums and oceanariums. Several pilot whales from southern California and Hawaii were taken into captivity during the 1960s and early 1970s,^[61][62] two of which were placed at SeaWorld San Diego. During the 1970s and early 1980s, six pilot whales were captured alive by drive hunts and taken for public display.^[4]

Pilot whales have historically had low survival rates in captivity, with the average annual survival being 0.51 years during the mid-1960s to early 1970s.^[62] There have been a few exceptions to the rule. Bubbles, a female short-finned pilot whale, who was displayed in Marineland of the Pacific and eventually at Sea World California, lived to be somewhere in her 50s when she eventually died on 12 June 2016.^[63] In 1968, a pilot whale was captured, given the name Morgan, and trained by the U.S. Navy's Deep Ops to retrieve deeper-attached objects from the ocean floor. He dove a record depth of 1654 feet and was used for training until 1971.^[64]

Films

There are two documentaries entirely dedicated to the pilot whales.

• Full-length Cheetahs of the deep (49’, 2014, directed by Rafa Herrero Massieu^[65]) — tells about the way of life, features of social interaction, the subtleties of hunting, games and breeding on the example of a group of non-migrating short-finned pilot whales living between the Islands of Tenerife and La Gomera of the Canary archipelago. A curious feature of the film is that: “all marine mammals filmed in freediving”.

• Short film My Pilot, Whale (28’, 2014, directed by Alexander and Nicole Gratovsky^[66]) demonstrates the possibility of interaction between humans and free-living pilot whales, offering the viewer a number of philosophical questions related to cetaceans: about their attitude to the world, what we have in common, what we — humans — can learn from them, and so on. The film has received a number awards of international film festivals.^[67][68]

See also

• Unihemispheric slow-wave sleep

References

Retrieved from "https://en.wikipedia.org/w/index.php?title=Pilot_whale&oldid=1157524295"

Sphaerocephalus es un género de musgos hepáticas de la familia Aulacomniaceae. Comprende 81 especies descritas y de estas, solo 4 aceptadas.^[1]​

Taxonomía

El género fue descrito por Neck. ex Lindb. y publicado en Utkast till en Naturlig Gruppering af Europas Bladmossor 37. 1878.^[2]​

Especies aceptadas

A continuación se brinda un listado de las especies del género Sphaerocephalus aceptadas hasta diciembre de 2014, ordenadas alfabéticamente. Para cada una se indica el nombre binomial seguido del autor, abreviado según las convenciones y usos.

• Sphaerocephalus acuminatum Lindb. & Arnell
• Sphaerocephalus heterostichus (Hedw.) E. Britton
• Sphaerocephalus palustris (Hedw.) Lindb.
• Sphaerocephalus turgidus (Wahlenb.) Lindb.

Referencias

Grinda (Globicephala) on delfiinlaste sugukonda kuuluv veeimetajate perekond.

Perekonda kuulub kaks liiki: tavagrinda (Globicephala melas) ja troopikagrinda (Globicephala macrorhynchus).

Nad toituvad peamiselt väikestest kaladest ja taimedest.

Grindad kuuluvad väheste menopausiga imetajate hulka.

Globicephala generoko zetazeoak Delphinidae familiaren parte dira. Muturrik gabeko itsas-ugaztunak dira eta pilotu-izurde edo kalderoi ere esaten zaie.

Bizkaiko golkoan, euskal kostaldean, pilotu-izurde hegaluzea ibili ohi da.

Espeziak

• Globicephala macrorhynchus
• Globicephala melas (pilotu-izurde hegaluzea)

Grindvalaat^[2] (Globicephala) on valaiden lahkoon ja delfiinien heimoon kuuluva nisäkässuku. Siihen kuuluu kaksi lajia:^[1]

• Pitkäeväpallopää^[3] eli pallopäävalas^[3][4], ehdotettu nimeä eväpallopää^[2] (Globicephala melas, synon. Globicephala melaena)
• Lyhyteväpallopää^[3], ehdotettu nimeä pallopää^[2] (Globicephala macrorhynchus).

Nisäkäsnimistötoimikunta on ehdottanut, että suvun suomenkieliseksi nimeksi vaihdettaisiin pallopäävalaat.^[2] Kyseinen nimi tarkoitti aiemmin Globicephalidae-heimoa, johon luettiin grindvalaiden lisäksi melonipäävalas (Peponocephala electra), kääpiömiekkavalas (Feresa attenuata), pikkumiekkavalas (Pseudorca crassidens) ja miekkavalas (Orcinus orca).^[3] Nykyisen luokittelun mukaan kaikki edellä mainitut lajit kuuluvat delfiinien heimoon (Delphinidae), jolle nimitys "Globicephalidae" on synonyymi.^[5]

Ulkonäkö

Pitkäevä- ja lyhyteväpallopäät eroavat toisistaan vain vähän. Yleensä lajeja ei voi erottaa toisistaan merellä niiden yhteisillä esiintymisalueilla.

Grindvalaat ovat väritykseltään mustia tai tummanharmaita. Täysikasvuiset urosvalaat voivat kasvaa 6,1 metriä pitkiksi ja painaa 3 tonnia, ja täysikasvuiset naaraat voivat kasvaa 4,9 metriä pitkiksi ja painaa 1,5 tonnia.

Esiintymisalue

Grindvalaita esiintyy trooppisissa ja lauhkeissa vesissä sekä pohjoisella että eteläisellä pallonpuoliskolla. Lyhytevä- ja pitkäeväpallopäiden esiintymisalueet ovat yhteisiä joillain alueilla, mutta useimmiten esiintymisalueet ovat erillisiä.

Lyhyteväpallopäävalaat elävät lämpimämmissä vesissä kuin pitkäeväpallopäävalaat, niitä esiintyy päiväntasaajan molemmin puolin sijaitsevalla leveällä vyöhykkeellä. Pitkäeväpallopäitä elää pohjois-Atlantilla ja Eteläisellä jäämerellä. Pohjois-Atlantilla, suunnilleen Espanjan leveysasteilta Kanariansaarten leveysasteille, on yhteinen esiintymisalue.

Elintavat

Uroksien elinikä on noin 45 vuotta ja naaraiden 60 vuotta. Grindvalaat saalistavat pääasiassa kalmareita.

Saalistustapa

Syvällä sukeltavia valaita pidetään yleensä hitaasti liikkuvina ja energiaa säästävinä eläiminä. Kansainvälinen tutkijaryhmä on tarkkaillut Kanariansaarten vesillä eläviä lyhyteväpallopäitä niihin kiinnitettyjen antureiden avulla. Anturit rekisteröivät valaiden nopeutta, syvyyttä ja suuntaa, ja valaiden ääntelyä ja valaiden kuulemia ääniä.

Lyhyteväpallopäiden on havaittu saalistaessaan uivan jopa nopeudella 32 km/h. Valaat voivat pitää nopeutta yllä noin 200 metrin matkan, jonka jälkeen ne joko saavat saaliin kiinni tai luovuttavat. Valaat saalistavat pilkkopimeässä yli 800 metrin syvyydessä kaikuluotaimensa avulla.

Lyhyteväpallopäiden saalistustapa muistuttaa gepardien saalistustapaa, jossa suurella nopeudella suoritetussa sprintissä kulutetaan paljon energiaa ja happea. Gepardit yli kaksinkertaistavat hengitystiheytensä sprintin aikana, mutta lyhyteväpallopäät saalistavat kuluttaen happea joka on sisäänhengitetty pinnalla.

Tutkijat ovat saaneet epäsuoria todisteita siitä, että valaat saalistavat muun muassa jättiläiskalmareita.

Lähteet

• Whales are 'cheetahs of the deep' 25. kesäkuuta 2008. BBC.
• Pilot whale American Cetacean Society. Viitattu 6. elokuuta 2008. Esiintymisalue-osio

Viitteet

Les globicéphales (Globicephala) sont un genre de cétacés odontocètes de la famille des delphinidés (les dauphins océaniques). Ils sont parfois appelés « dauphins-pilotes » car on les voit fréquemment dans le sillage ou à l’étrave des navires (en anglais finned pilot whale). Dauphins au melon frontal fortement développé, ce sont des animaux sociaux qui se déplacent le plus souvent en bandes pouvant aller d'une dizaine à plusieurs centaines d'individus^[1].

Classification

Liste des espèces actuelles

Selon ITIS (10 février 2017)^[2] et Mammal Species of the World (version 3, 2005) (10 février 2017)^[3]:

• Globicephala macrorhynchus Gray, 1846 - le Globicéphale tropical
• Globicephala melas (Traill, 1809) - le Globicéphale noir

• Globicephala macrorhynchus

• Globicephala melas

Liste des espèces éteintes

Selon Paleobiology Database (février 2017)^[4]:

• † Globicephala etruriae Pilleri, 1987
• † Globicephalus karsteni Olfers, 1839
• † Globicephala uncidens Lankester, 1864

Notes et références

Voir aussi

Ainmhí mara mór is ea an píolótach. Céiticeach atá ann, ball den ghéineas Globicephala.

Is síol é an t-alt seo. Cuir leis, chun cuidiú leis an Vicipéid.
Má tá alt níos forbartha le fáil i dteanga eile, is féidir leat aistriúchán Gaeilge a dhéanamh.

Globicephala é un xénero de cetáceos odontocetos da familia dos delfínidos catacterizados sobre todo poque o seu melón frontal está moi desenvolvido, o que fai que teñan a cabeza bulbosa, máis pronuciada nos machos adultos,^[4] e ao que alude o nome do xénero, Globicephala, literalmente "os de cabeza en forma de globo", e que en galego coñécense como caldeiróns.^[5]

Son animais sociais que se desprazan frecuentemente en grupos que oscilan entre unha decena e varios centos de individuos.^[4]

Taxonomía

Descrición

O xénero Globicephala foi creado por Lesson en 1828, aparecendo por primeira vez en Compl. Oeuvres Buffon Hist. Nat., 1: 441, tomando como especie tipo a Delphinus globiceps Cuvier, 1812 (= Delphinus melas Traill, 1809).^[6]

Sinonimia

Ao longo do temmpo, o xénero foi coñecido polos sinónimos seguites:^[6]

• Cetus Wagler, 1830
• Globiceps Flower, 1884
• Sphaerocephalus Gray, 1864

Clasificación

O xénero comprende dúas especies,^[3] unha delas con dúas subespecies:^[6]

• Globicephala macrorhynchus (Gray, 1846) – caldeirón tropical
• Globicephala melas (Traill, 1809) – caldeirón propiamente dito, ou caldeirón común.
  • Globicephala melas melas – no Atlántico norte.
  • Globicephala melas edwardii – no Hemisferio sur.

Nota taxonómica

Segundo van Bree (1971), antigamente a especie denominábase Globicephala melaena, pero segundo o artigo 31b da terceira edición do Código internacional de nomenclatura zoolóxica (1985), da Comisión Internacional de Nomenclatura Zoolóxica, modificouse en melas, como exemplo dun adxectivo grego que non cambia a súa terminación cando se transfire dun xénero no que previamente figuraba a outro posterior (sen modificar, por tanto, a concordancia gramatical entre nome xenérico e específico.^[6]

Estado das poboacións

En 2008, a Unión Internacional para a Conservación da Natureza cualificou o estado de conservación das poboacións de ambas as especies como "DD" (datos insuficientes).

No caso de Globicephala melas, en primeiro lugar, porque é tratada como unha soa especie, aínda que puidera tratarse de dúas ou máis (do que non hai de momento probas) e, se así fora, algunhas destas poboacións poderían xustificar o seu listado en categorías superiores de risco.^[1]

As principais ameazas que poderían causar caídas importantes das súas poboacións son actuacións antropoxénicas, como o aumento dos ruídos dos sonares, especielmente dos militares e os empregados nas prospeccións sísmicas, e as captutras accidentais na pesca, especialmente na de luras,^[1] calculándose que podería reducir a súa poboación global nun 30 % ao longo de tres xeracións.^[7]

En canto a Globicephala macrorhynchus, as razóns aducidas pola UICN son as mesmas que para a especie anterior.^[2]

Notas

Véxase tamén

Bibliografia

• Carwardine, Mark (1995): Ballenas, delfines y marsopas. Barcelona: Ediciones Omega. ISBN 84-282-1037-3.
• Perrin, William F., Bernd Würsig & J. G. M. Thewissen (eds.) (2002): Encyclopedia of Marine Mammals. 2ª ed. San Diego: Academic Press. ISBN 978-0-12-373553-9
• Wilson, D. E. & Reeder, D. M. (eds.) (2005): Mammal Species of the World. A Taxonomic and Geographic Reference. Third edition. ISBN 0-8018-8221-4.

Outros artigos

• Cetáceos
• Odontocetos
• Delfínidos
• Grampus griseus

Paus pilot adalah cetacean yang masuk dalam genus Globicephala. Dua spesies yang masih hidup yakni Paus-pilot sirip-pendek (G. macrorhynchus) dan Paus-pilot sirip-panjang (G. melas). Kedua spesies sulit dibedakan di laut, dan analisis tengkorak adalah cara yang paling baik untuk melihat perbedaannya.

Referensi

Grindhvalir (eða grind, en einnig nefnd marsvín) er ættkvísl tannhvala af höfrungaætt og er mjög algengur við Íslandsstrendur. Grindhvalirnir eru í aðalatriðum líkir höfrungum, en mun stærri og höfuðsvipurinn allur annar. Ennið er mjög kúpt og snjáldrið mjög stutt og ekki afmarkað frá enninu.

Tengt efni

• Grindadráp

Globicephala Lesson, 1828 è un genere di cetacei odontoceti cui appartengono due specie. Il genere fa parte della famiglia dei Delphinidae, sebbene il loro comportamento sia più vicino a quello delle grandi balene. Le due specie sono il globicefalo (Globicephala melas) e il globicefalo di Gray (Globicephala macrorhynchus). In mare non sono facilmente distinguibili l'una dall'altra e vengono chiamate solo semplicemente globicefali o calderón, in spagnolo.

Descrizione

Sono di colore completamente nero o grigio molto scuro. La pinna dorsale è situata piuttosto avanti sul dorso ed è rivolta all'indietro. La pinna dorsale dei cuccioli è flessibile alla nascita, così da facilitare il processo del parto. Il corpo è allungato ma robusto e si restringe notevolmente nei pressi della pinna caudale.

Le differenze nell'aspetto delle due specie sono molto sottili e dove i loro areali si sovrappongono è generalmente impossibile in mare capire di quale specie si tratta. A terra gli esemplari si possono distinguere dalla lunghezza delle pinne pettorali, dal numero dei denti e dalla forma del cranio: il G. melas, soprattutto i maschi più vecchi, ha una testa più bulbosa; il G macrorhynchus l'ha squadrata e la fronte oltrepassa sensibilmente la bocca. G. macrorhynchus venne descritto, sulla base solamente di materiali scheletrici, da John Edward Gray nel 1846. Dallo scheletro presunse che il cetaceo avesse un grosso rostro ("macrorhynchus", in latino).

Il peso dei piccoli alla nascita si aggira intorno ai 100 kg. I maschi adulti possono raggiungere i 6,1 m e pesare fino a 3 tonnellate. Le femmine adulte misurano fino a 4,9 m di lunghezza e pesano fino a 1,5 tonnellate. La vita media è di circa 45 anni nei maschi e 60 anni nelle femmine di entrambe le specie.

Entrambe le specie vivono in gruppi in media di circa 10-30 esemplari, ma alcuni gruppi possono anche raggiungere i 100 o più. Sono abbastanza attive e spesso sbattono la coda sulla superficie delle onde, mettono la testa fuori dall'acqua e si avvicinano alle imbarcazioni.

Si nutrono principalmente di calamari. Rispetto agli altri odontoceti imparentati con loro hanno molti meno denti; solamente 30-40, rispetto ai 120 del tursiope. Questo si pensa che sia un adattamento ad una dieta a base di calamari.

Popolazione e distribuzione

Sono tra i mammiferi marini dell'ordine dei cetacei più comuni e largamente distribuiti.

G. melas preferisce acque leggermente più fredde di G. macrorhynchus e si divide in due popolazioni. Il gruppo più grande si trova in una fascia circumpolare nell'oceano Meridionale che va approssimativamente dai 20° S ai 65° S. Può essere avvistata al largo delle coste di Cile, Argentina, Sudafrica, Australia e Nuova Zelanda. La popolazione di questo gruppo viene stimata in oltre 200.000 individui. La seconda popolazione è molto più piccola e abita l'oceano Atlantico settentrionale, in una fascia che va dalla Carolina del Sud negli Stati Uniti alle Azzorre e al Marocco a sud e da Terranova e dalla Groenlandia all'Islanda e alla Norvegia settentrionale a nord. È presente anche nella metà occidentale del mar Mediterraneo.

La popolazione di G. macrorhynchus è più numerosa. Si trova nelle acque temperate e tropicali degli oceani Indiano, Atlantico e Pacifico. La popolazione nell'Atlantico occidentale si sovrappone leggermente a quella di G. melas. Nell'oceano Pacifico orientale tropicale sono presenti 150.000 individui. Nel Pacifico occidentale si stima che vivano più di 30.000 animali, al largo delle coste del Giappone.

Entrambe le specie preferiscono le acque profonde.

Interazioni con l'uomo

La prospettiva di una sopravvivenza a lungo termine per entrambe le specie è ben assicurata. Infatti nella sua Lista Rossa delle Specie Minacciate la IUCN classifica entrambe le specie a "basso rischio; dipendenti dalla conservazione".

G. melas è stata tradizionalmente cacciata dai balenieri con la cosiddetta tattica della "guida" - in cui molti pescatori e imbarcazioni circondavano un gruppo di balene per poi spingerle lentamente a riva, dove le uccidevano. Questa pratica è stata comune sia nel diciannovesimo che nel ventesimo secolo, declinando solamente negli anni novanta. Negli anni ottanta in questa maniera venivano uccisi ogni anno circa 2500 individui. Attualmente questo tipo di caccia, chiamata Grindadráp, viene effettuata solo sulle Isole Fær Øer - dove vengono uccisi ogni anno circa 1000 animali.

Anche G. macrorhynchus è stato cacciato per molti secoli, soprattutto dai balenieri giapponesi. A metà degli anni '80 i giapponesi uccidevano 2300 animali all'anno. Questo numero è sceso a 400 all'anno negli anni '90. Le uccisioni con l'arpione sono ancora relativamente comuni nelle Piccole Antille, in Indonesia e nello Sri Lanka. Dal momento che queste catture non vengono registrate non sappiamo con esattezza quante catture vengano effettuate ogni anno e l'effetto che hanno sulla popolazione locale.

Entrambe le specie rimangono uccise ogni anno a centinaia o forse a migliaia lungo la linea costiera e nelle reti d'altura.

Bibliografia

• National Audubon Society Guide to Marine Mammals of the World ISBN 0-375-41141-0
• Encyclopedia of Marine Mammals ISBN 0-12-551340-2
• Whales, Dolphins and Porpoises, Mark Carwardine, ISBN 0-7513-2781-6

De grienden (Globicephala) vormen een geslacht uit de familie der dolfijnen (Delphinidae). Tot dit geslacht behoren twee soorten, de gewone griend (Globicephala melas) en de kleinere Indische griend (Globicephala macrorhynchus), en ze behoren tot de grootste soorten dolfijnen. Grienden behoren samen met enkele andere grotere dolfijnen tot de onderfamilie der zwartvissen (Globicephalinae).

Kenmerken

De kop is bolvormig met een lichtelijk uitstekende bovenlip. De rest van het lichaam is stevig. De grienden zijn zwart op de rug en de flanken. De buik van de griend is grijs, die van de Indische griend voornamelijk zwart. Op de kin zit een ankervormige, grijze vlek. De flippers zijn lang en sikkelvormig en de rugvin is vrij laag met een brede basis. De gewone griend heeft ietwat langere flippers dan de Indische griend. Ook heeft de gewone griend meer tanden. Mannetjes in dit geslacht worden groter dan vrouwtjes. Mannetjes worden 4,5 tot 7,6 meter lang en 2500 tot 3500 kilogram zwaar, vrouwtjes 3,3 tot 5,6 meter lang en 1300 tot 2500 kilogram zwaar.

Leefwijze

Grienden komen voor in alle subpolaire tot tropische zeeën. Er is veel overlap tussen de verspreidingsgebieden van beide soorten. Ze leven voornamelijk in grote familiegroepen op open zee. De belangrijkste prooi is pijlinktvis en schoolvissen. Ze springen slechts zelden op uit het water. Volwassen mannetjes kunnen zeer agressief zijn tegenover andere mannetjes, en veel mannetjes hebben meerdere littekens over het lichaam.

Voortplanting

Na een draagtijd van ongeveer vijftien maanden wordt één jong geboren van tussen de 140 en 180 centimeter lang. De zoogtijd duurt meer dan een jaar.

Er werd aangetoond dat de beide soorten van dit geslacht kunnen hybridiseren.^[1]

Bronnen, noten en/of referenties

Grindhvaler (Globicephala), i noen grad også kalt pilothvaler, er ei slekt med delfiner som består av to arter med tannhvaler.

Arter og tilhørighet

• Globicephalinae (grindhvaler og melonhodedelfiner)
  • Globicephala (grindhvaler)
    • Globicephala macrorhynchus (kortfinnegrindhval)
    • Globicephala melas (grindhval)

Eksterne lenker

• (sv) grindhvaler og melonhodedelfiner hos Dyntaxa
• (en) grindhvaler og melonhodedelfiner – oversikt og omtale av artene i WORMS-databasen
• (en) grindhvaler og melonhodedelfiner i Encyclopedia of Life
• (en) grindhvaler og melonhodedelfiner i Global Biodiversity Information Facility
• (en) grindhvaler og melonhodedelfiner hos Fossilworks
• (en) grindhvaler og melonhodedelfiner hos NCBI
• (en) grindhvaler og melonhodedelfiner hos ITIS
• (en) Kategori:Globicephala – bilder, video eller lyd på Wikimedia Commons
• Globicephala – detaljert informasjon på Wikispecies

Multimedia w Wikimedia Commons

Grindwal^[6] (Globicephala) – rodzaj ssaka z rodziny delfinowatych (Delphinidae).

Występowanie

Rodzaj obejmuje gatunki występujące we wszystkich oceanach i morzach świata^[7].

Systematyka

Nazewnictwo

Nazwa rodzajowa jest połączeniem łacińskiego słowa globus – „piłka, kula” oraz greckiego słowa κεφαλη kephalē – „głowa”^[8].

Gatunek typowy

Delphinus globiceps Cuvier, 1812 (= Delphinus melas Traill, 1809)

Podział systematyczny

Do rodzaju należą następujące gatunki^[6][7]:

• Globicephala macrorhynchus – grindwal krótkopłetwy
• Globicephala melas – grindwal długopłetwy

Uwagi

Przypisy

O termo baleia-piloto é a designação comum aos mamíferos cetáceos do gênero Globicephala, que ocorrem nos oceanos de todo o mundo. Tais mamíferos chegam a medir até 8,5 metros de comprimento, de coloração negra, cabeça em forma de globo sem bico definido e dentes presentes. Também são chamados de globicéfalo, caldeirão e golfinho-piloto.

Espécies

• Baleia-piloto-de-peitorais-longas (Globicephala melas)
• Baleia-piloto-de-peitorais-curtas (Globicephala macrorhynchus)

Globicephala^[1] är ett släkte av däggdjur som beskrevs av René-Primevère Lesson 1828. Globicephala ingår i familjen delfiner.^[1][2]

Arter enligt Catalogue of Life^[1], Dyntaxa^[2] och Wilson & Reeder (2005)^[3]:

• Kortfenad grindval (Globicephala macrorhynchus)
• Långfenad grindval (Globicephala melas)

Källor

1. ^ [a b c] Bisby F.A., Roskov Y.R., Orrell T.M., Nicolson D., Paglinawan L.E., Bailly N., Kirk P.M., Bourgoin T., Baillargeon G., Ouvrard D. (red.) (28 april 2011). ”Species 2000 & ITIS Catalogue of Life: 2011 Annual Checklist.”. Species 2000: Reading, UK. Arkiverad från originalet den 18 juni 2012. https://web.archive.org/web/20120618223324/http://www.catalogueoflife.org/services/res/2011AC_26July.zip. Läst 24 september 2012.
2. ^ [a b] Dyntaxa Globicephala
3. ^ Wilson & Reeder, red (2005). ”Globicephala” (på engelska). Mammal Species of the World. Baltimore: Johns Hopkins University Press. ISBN 0-8018-8221-4

Externa länkar

• Wikimedia Commons har media som rör Globicephala.
  Bilder & media
• Wikispecies har information om Globicephala.
  Artförteckning

? Pilot balina Bilimsel sınıflandırma Âlem: Animalia Şube: Chordata Sınıf: Mammalia Takım: Cetacea Familya: Delphinidae
Cins: Globiceohala
Tür: Globicephala melaena
Gray, 1846 Dağılım haritası Pilot balinanın yaşam alanları...

Morfoloji

Pilot balinalar; gri, kahverengi veya siyah renkelere sahiptirler. Göç etmeyen alt türler daha koyu bir renktedir. Erkeklerin boyu 8,5 metre, dişilerin boyu ise 6 metreye varabilir. Ağırlıkları erkek bireyler için azami 3,5 ton, dişiler için ise 2,5 tondur. Kafası köşeli ve dar bir yapıdadır. Ağzı küçüktür. Boğazı ve alt kısmı diğer yerlerinden daha açıktır. Üst çenesinde 13, alt çenesinde 8 diş bulunur.

Beslenme

Pilot balinaların ana besini mürekkep balığıdır. Bu besini bulamadığı zamanlarda daha küçük balıklarla beslenir. Beslenme gibi bir sorunu yoktur. İhtiyacını bir şekilde giderir.

Coğrafya ve habitat

Pilot balinalar dondurucu bir soğukluğa sahip suları tercih ederler veya sıcaklığın 0-25 °C olduğu sularda yüzerler. Bunlar da genelde okyanuslardır.

Beslenmek için sığ suları tercih ederler. Yaz aylarında Batı Kanada'ya göç ederler.

Hareket biçimi

Tipik bir pilot balina sürüsü 50 - 100 bireyden oluşur. Akrobatik değillerdir. Yüzeyde durmaya ve yavaş yüzmeye dikkat ederler. Kendi aralarında iletişim kurmak için çıkarttıkları sesler vardır.

Davranış

Balıkçılar bu balina türünü su altında ringa bulmak amacıyla kullanırlardı. Bu yüzden bu balinaya "pilot balina" adını verdiler.

Pilot balinaların güçlü sosyal bağları vardır. Grubun bir üyesi herhangi bir nedenden dolayı yaralanır veya hastalanırsa diğerleri onu korumak için çevresini sararlar. Adeta etten bir duvar örerler. Pilot balinaların yaşam süreleri 40-50 yıl arasında değişir. Balinalar göç esnasında liderlerini takip ederler. Bu sayede bireyler sürüden ayrılmaz.

İnsanla ilişkileri

1888 yılında 100 tane pilot balina yakalanmış ve avlanmaları bugüne kadar süregelmiştir. Kıyılara yakın olduklarından dolayı yakalanmaları oldukça kolaydır. İnsanlar yüzyıllardır bu türü avlamak için Kuzey Atlantik'te ava çıkmışlardır. 1936-1978 yılları arasında yılda ortalama 1552 tane pilot balina avlanmıştır. 1941 yılında beklenmedik bir şekilde Faroe Adaları'nda 4325 adet pilot balina yakalanmıştır. Tüm protestolara rağmen Faroe Adaları'daki avlanma devam etmekte ve denizlerde hala kan akmaktadır. Bu avın yapılma sebebi yöresel bir yemek olan Grind Og Spik yemeğini yapmak içindir.

Dış Kaynaklar

• Ege Üniversitesi

• 1 Опис
• 2 Спосіб життя
• 3 Галерея
• 4 Література
• 5 Посилання

Chi Cá voi hoa tiêu (danh pháp khoa học: Globicephala) là một chi thuộc Họ Cá heo đại dương. Chi này có hai loài đang tồn tại. Hai loài này là không dễ dàng phân biệt trên biển và phân tích của hộp sọ là cách tốt nhất để biết sự khác biệt giữa chúng. Giữa hai loài, cá voi hoa tiêu có phạm vi phân bố trong vùng biển gần với cá voi hoa tiêu vây dài sống ở vùng nước lạnh và cá voi hoa tiêu vây ngắn sống ở vùng biển nhiệt đới và cận nhiệt đới trên toàn thế giới. Cá voi hoa tiêu là một trong những loài cá voi lớn nhất, vượt quá kích thước của cá voi sát thủ.

Cá voi hoa tiêu chủ yếu ăn cá mực, nhưng cũng ăn cá. Chúng có tính xã hội cao và nghiên cứu cho rằng cả con đực và con cái vẫn còn trong tốp của các bà mẹ, một đặc điểm bất thường giữa các động vật có vú, cũng được tìm thấy trong một số cộng đồng cá voi sát thủ. Cá voi hoa tiêu vây ngắn cũng là một trong vài loài động vật có vú nơi phụ nữ đi qua thời kỳ mãn kinh,

Các loài

• Globicephala macrorhynchus: cá voi hoa tiêu vây ngắn
• Globicephala melas: cá voi hoa tiêu vây dài

Chú thích

Tham khảo

Царство: Животные

Подцарство: Эуметазои

Без ранга: Двусторонне-симметричные

Без ранга: Вторичноротые

Тип: Хордовые

Подтип: Позвоночные

Инфратип: Челюстноротые

Надкласс: Четвероногие

Класс: Млекопитающие

Подкласс: Звери

Инфракласс: Плацентарные

Надотряд: Лавразиотерии

Отряд: Китообразные

Подотряд: Зубатые киты

Семейство: Дельфиновые

Род: Гринды

• Cetus Wagler, 1830
• Globiceps Flower, 1884
• Sphaerocephalus Gray, 1864^[1]

• Короткоплавниковая гринда

(G. macrorhynchus)

• Обыкновенная гринда (G. melas)

Globicephala macrorhynchus Globicephala melas Оба вида

У этого термина существуют и другие значения, см. Чёрный дельфин (значения).

• 1 Описание
• 2 Галерея
• 3 См. также
• 4 Примечания
• 5 Литература

В Викисловаре есть статья «гринда»

綠色：長肢領航鯨的分佈地
藍色：短肢領航鯨的分佈地

種

• 短肢領航鯨 G. macrorhynchus
• 長肢領航鯨 G. melas

領航鯨是圓頭鯨屬下的兩個物種，圓頭鯨亞科又名領航鯨亞科、圓頭鯨屬又名領航鯨屬，即長肢領航鯨及短肢領航鯨。雖然牠們的行為很像鯨魚，但卻是屬於海豚科的。

特徵

領航鯨呈黑色或非常深的灰色。背鰭位於背部較前位置，並向後彎。初生的領航鯨背鰭非常柔軟，以方便生殖。牠們的身體粗壯，並向尾巴收窄。

雌性的體型比雄性的薄。長肢領航鯨及短肢領航鯨的分別很少，在重疊的分佈地一般很難在海中分辨。牠們的分別在於腹鰭的長度、牙齒的數目及頭顱骨的形狀。短肢領航鯨的頭較圓，而長肢領航鯨的頭則較方。

出生時的領航鯨體重約為100公斤。成年雄鯨可以長達6.1米及重3噸。成年雌鯨則長4.9米及重1.5噸。^[1]雄鯨壽命約為45歲，而雌鯨的則為60歲。

兩種領航鯨都是群居的，成員約有10-30隻，有些甚至多達100隻或以上。牠們較為活躍，經常會拍尾、跳躍及游近船隻。

領航鯨喜歡吃烏賊。牠們只有30-40顆牙齒，與其他有齒的鯨類比較很少。這相信是牠們對覓食烏賊的適應性有關。

數量及分佈

領航鯨是鯨目中最為普遍及分佈最廣的之一。長肢領航鯨喜歡較冷的海域及分為兩個群落。較大群的數目估計超過20萬隻，分佈在南冰洋的繞極帶，由南緯20°-65°。在智利、阿根廷、南非、澳洲及新西蘭對出海岸可以見到牠們。另一群的數量較少及分佈在北大西洋，由美國南卡羅萊納州向南橫跨至亞速爾群島及摩洛哥，及北面由紐芬蘭島至格陵蘭、冰島及挪威北部。牠們也分佈在地中海的西半。

短肢領航鯨較為稠密。牠們分佈在印度洋、大西洋及太平洋的溫帶及熱帶水域。西大西洋是牠們與長肢領航鯨重疊的分佈地。在熱帶東太平洋估計牠們的數量就有達15萬隻；而在日本對出的西太平洋就估計有多達3萬隻。

領航鯨較為喜歡深水的水域。

捕鯨

長肢領航鯨會被捕鯨船形成的半圓所圍捕。當牠們在近岸被發現時，就會慢慢被逼入海灣中。漁民會拋石到水中，逼使牠們走上海灘上擱淺及被殺。這種捕鯨法於19世紀及20世紀甚是普遍。現時則只有法羅群島仍採用此方法捕鯨。研究指於1980年代開始，每年就有約1500條長肢領航鯨被殺；於1990年代就下降至只有少於1000條。

短肢領航鯨也被獵殺了多個世紀，尤其是在日本。於1980年代中葉，日本漁民每年就殺死約2300條短肢領航鯨。到了1990年代就下降至約400條。在小安的列斯群島及斯里蘭卡仍有使用魚叉捕獵的方法。

參考

• National Audubon Society Guide to Marine Mammals of the World ISBN 0-375-41141-0
• Encyclopedia of Marine Mammals ISBN 0-12-551340-2
• Whales, Dolphins and Porpoises, Mark Carwardine, ISBN 0-7513-2781-6

外部連結

• Short-finned Pilot Whales in Hawaii

取自“https://zh.wikipedia.org/w/index.php?title=領航鯨&oldid=52459648”

ゴンドウクジラ属 分類 界 : 動物界 Animalia 門 : 脊索動物門 Chordata 亜門 : 脊椎動物亜門 Vertebrata 綱 : 哺乳綱 Mammalia 亜綱 : 獣亜綱 Theria 目 : 鯨偶蹄目 Cetartiodactyla 亜目 : ハクジラ亜目 Odontoceti 上科 : マイルカ上科 Delphinoidea 科 : マイルカ科 Delphinidae 属 : ゴンドウクジラ属 Globicephala 学名 Globicephala
(Lesson, 1828) 種

• ヒレナガゴンドウ G. melas
• コビレゴンドウ G. macrorhynchus

本文参照

ゴンドウクジラ属（ゴンドウクジラぞく、巨頭鯨属、学名：Globicephala）は、鯨偶蹄目ハクジラ亜目マイルカ科に属する属の1つ。ヒレナガゴンドウ（英: Long-finned Pilot Whale, 学名：G. melas）とコビレゴンドウ（英: Short-finned Pilot Whale, 学名：G. macrorhynchus）の2種で構成される。

ゴンドウクジラ属はイルカとして扱われる種が多く属するマイルカ科に分類されるが、その形態は、口吻が額のメロンより先にあまり長く突出しておらず、いわゆるイルカらしい顔つきをしていない。そのため、体の大きさや系統分類学的位置からは十分イルカとして扱われておかしくないにもかかわらず、慣習的にイルカとしては扱われず、クジラとして扱われることが多い。ゴンドウイルカと呼ばれることもある。

分類[編集]

• ゴンドウクジラ属 Globicephala (Lesson, 1828)
  • ヒレナガゴンドウ Globicephala melas (Traill, 1809)
  • コビレゴンドウ Globicephala macrorhyncus Gray, 1846
    • マゴンドウ（亜種）
    • シオゴンドウ（タッパナガ）（亜種）

ヒレナガゴンドウとコビレゴンドウ[編集]

ゴンドウクジラ属の体表は真っ黒かあるいは濃い灰色である。頭部が丸く、若干ずんぐりむっくりしている。

ヒレナガゴンドウとコビレゴンドウはかなり良く似ている。分布が重なっている海域ではこれらを区別することは困難であるが、胸びれの長さ、歯の本数、頭の形などにより判別することが可能である。コビレゴンドウ、特に年を取った雄の頭は丸い。ヒレナガゴンドウはコビレゴンドウよりも若干頭が四角く、額が口よりも前にせり出している。

出産直後の体重は60kg程度である。成体の体長は4-7m、体重は1,000-3,000kgである。寿命は雄が45歳、雌が60歳程度である。

共に10頭から30頭程度の群れを成して行動する。非常に活発に行動し、人間のボートに近づくこともしばしばある。

主食はイカである。またゴンドウクジラとマグロはしばしば同じ海域で見られる。これはゴンドウクジラがマグロを食べるからではなく^[1]、共にイカを食べるからであると考えられている（えびす#多様な神格とその由来も参照）。

ゴンドウクジラは他のクジラに比べて、海岸に乗り上げてしまうことが多い。これは、海岸近くで産卵するイカを追いかけて海岸まで来てしまうのだろうと考えられている（ただし、座礁には様々な説がある）。 オーストラリア南西部の海岸の例では、1996年にヒレナガゴンドウが約320頭、2018年にはコビレゴンドウが約150頭が打ち上げられている^[2]。

コビレゴンドウは日本近海に形態が異なる2タイプの亜種が生息している。通常マゴンドウとよばれるタイプと、一回り大きく形態が異なるタッパナガと呼ばれるタイプであるであり、両種は寒流と暖流の潮目である銚子付近を境に別個分布している。タッパナガはシオゴンドウとも呼ばれコビレゴンドウと別種とする説も一部にある。

また、ヒレナガゴンドウは北太平洋では見られないが、日本国内（北海道礼文島や千葉県）の遺跡からの発掘調査で部分的骨格が発見され、かつては少なくとも日本沿岸に生息していた事が確認されている。一説には、ヒレナガゴンドウの地方絶滅が今日のタッパナガとよばれる北方形態の誕生を促したとされている。^[3]　失われたヒレナガゴンドウのニッチにコビレゴンドウが入り込み進化適応したという原理である。

日本における展示飼育[編集]

日本における初のコビレゴンドウの展示飼育は、1936年（昭和11年）、阪神水族館による^[4][5][6]。これは和歌山県東牟婁郡太地町で捕獲された4頭を約660m²の楕円形の屋外プールで飼育したものであり、簡単な芸も披露するまでになった^[5]。鈴木は水族館におけるクジラ類の飼育としては世界でも最初期の事例であろうと指摘している^[7]。

神奈川県の江の島水族館においては、開館以来、太地町で捕獲されたコビレゴンドウを度々飼育していた。コビレゴンドウを沿岸捕鯨で捕っている和歌山県太地町のくじらの博物館では継続飼育を行っている。殆どの施設で飼育されるコビレゴンドウはマゴンドウであるが、八景島シーパラダイスではタッパナガが飼育されている。

人間との関り[編集]

食料として見た場合、コビレゴンドウの体内に含まれる微量の水銀に妊婦は注意する必要がある。 厚生労働省は、コビレゴンドウを妊婦が摂食量を注意すべき魚介類の一つとして挙げており、2005年11月2日の発表では、1回に食べる量を約80gとした場合、コビレゴンドウの摂食は2週間に1回まで（1週間当たり40g程度）を目安としている^[8]。

脚注[編集]

「https://ja.wikipedia.org/w/index.php?title=ゴンドウクジラ属&oldid=67860658」から取得

거두고래속(Globicephala)은 참돌고랫과에 속하는 이빨고래의 한 속이다.^[1] 참거두고래와 들쇠고래의 두 종을 포함한다.

각주