North Atlantic Right Whale (북대서양참고래)

 

북대서양참고래(Eubalaena glacialis)

영명 : North Atlantic Right Whale, Northern Right Whale

 

 

몸길이 : 13.5~17m, 몸무게 : 40∼80t. 몸빛깔은 검은색이며, 배꼽 부근에 불규칙한 흰 얼룩이 있는 개체가 많다. 머리는 커서 몸길이의 4분의 1이나 된다. 몸통은 길이에 비해 나비가 넓다. 허리둘레도 상당히 길어 몸길이의 약 60％ 이상이다.
위턱은 가늘고 길게 앞을 향해 아치형으로 자라고, 입 속에는 약 230개의 긴 고래수염이 있다. 고래수염은 회갈색 또는 검은색으로 최대 길이 약 3m이다. 수염은 매우 가늘어 작은 먹이를 걸러 먹는 데에 알맞다. 분기공은 2개이며 넓게 분리되어 있고 공기를 내뿜을 때에는 V자 모양으로 높이 4∼8m에 이른다.  

등지느러미는 없고, 가슴지느러미와 꼬리지느러미는 크다. 위턱은 활 모양으로 가늘고 앞부분에 사마귀 같은 피부 돌기가 있다. 몸의 색깔은 흑색이며 배꼽 부근에 불규칙한 흰 반점이 있다. 복부 주름은 없다. 고래수염은 길고 흑색이다. 머리부위에 혹 모양의 융기가 있다. 머리 부분의 피부에는 경결(티눈)이 곳곳에 흩어져 있어 여기에 따개비 등이 붙어 있다. 그 중 가장 큰 경결이 분수공의 앞쪽에 있다. 피부의 지방층 두께는 최대 40cm로 두꺼운 편이다. 등지느러미는 없으며 가슴지느러미는 넓고 끝이 체처럼 넓적하다. 꼬리지느러미의 나비는 몸길이의 약 1/3이며 가운데에 V자 모양의 큰 벤자리가 있다.

짝짓기 시기가 되면 암컷 1마리를 상대로 여러 마리의 수컷이 경쟁하며 많은 양의 정액을 방출해서 다른 수컷을 쫓는다. 3∼4년에 1회 출산하며 임신기간은 10∼12개월이다. 갓 태어난 새끼의 몸길이는 4.5∼5m이고, 몸길이가 14.5∼15.5m가 되어야 성적으로 성숙한다.

 

살이 쪄서 둥근 몸매를 하고 있으며, 대개 느린 속도로 헤엄치면서 표층 부근에 모인 먹이를 입을 벌린 채 바닷물과 함께 들이켜 먹이를 걸러먹는다. 주로 작은 갑각류를 먹는다. 이동할 때에는 12마리 이하, 주로 1∼2마리씩 무리를 이루어 헤엄친다. 헤엄치는 속도가 별로 빠르지 않은데다 옛날부터 포경의 주요 대상이었기 때문에 그 수가 절멸의 위기에 처할 만큼 크게 줄어 국제조약에 의해 포획이 금지되었다.

 

북반구의 온난수역, 북대서양에 서식한다. 여름철 추운 연안에 분포한다. 우리 나라 제주도 부근과 동해에 서식하였으나 최근에는 오호츠크해에서 관찰된다.

◈ 북대서양 (서부) : 300~500 마리. 

 

 

   

 

  

 

 

 

 

 

               

 

               

 

                   

 

Description
The northern right whale is the most endangered of the great whales. This species received its name from whalers who considered it to be the 'right' whale to hunt; they swim slowly, float when dead and contain high quantities of oil and baleen. The northern right whale is a bulky species, black in colour with patches of white on the chin and underside, and a large head relative to the body. A number of 'callosities' (thickened rough patches of skin) occur at various points on the body, and these are covered in whale lice (Cyamus spp.) so that they appear whitish yellow. These callosities tend to be larger in males than females, and on the head and jaw the pattern is unique, allowing individuals to be identified. Females are larger than males, and juveniles are usually bluish in colour, becoming darker as they age. From a distance the species can be identified by the characteristic v-shaped blow, which can reach up to 5m in height.

 

Range
The majority of northern right whales are found in the western North Atlantic, off the coasts of Canada and North America, with a worldwide population estimated at less than 320. Only a few individuals are thought to remain in the eastern North Atlantic and North Pacific Oceans.

 

Habitat
Inhabits temperate and sub-polar waters and calves in shallow waters close to the shore. Poorly understood migrations take place between northern feeding grounds and southern calving sites.

 

Biology
The callosities on the body are infested with parasitic whale lice. The function of these patches is unknown, but one theory is that males use them in competing for females. This whale produces a variety of low-frequency sounds; contact calls between individuals separated by a large distance and calls that females use to attract mates have both been studied. The northern right whale feeds by filtering small crustaceans from the water using the baleen plates. Individuals swim through a swarm of prey with the head slightly above water and the mouth open. When the prey has been filtered through the baleen the water is driven out. This species can dive to depths of 50m for 15~20 minutes. Females give birth every 2 to 4 years, between February and April after a gestation period of about a year. Infants measure around 5.5m at birth, and are nursed for 6 to 7months, they stay close to their mother, who may occasionally roll onto her back and hold the calf in her flippers. This species tends to occur in small groups of around six individuals. In winter, individuals migrate to the breeding and mating grounds in warmer seas to the south, and return to the colder food-rich feeding grounds in summer, but few precise details of the migratory behaviour of the species are known.

 

Threats
The main threat to the northern right whale has been hunting, which was once a lucrative industry. Whales were hunted for oil and 'whalebone' (from the baleen), which was used in whips, umbrellas, corsets and skirts. This species was almost hunted to extinction by 1800; after years of protection the population still numbers less than a few hundred amd the species remains at risk. Their preference for coastal waters renders these whales particularly vulnerable to mortality caused by fishing gear and collisions with ships.

 

Conservation
The northern right whale has been protected internationally since 1935, but has not recovered from earlier persecution. The United States has taken measures following the production of a Recovery Plan, these include fishing area closures, and modifications to fishing gear. The southeast of the United States, Cape Cod Bay and the Great South Channel have been designated as critical right whale habitat, and a number of key areas off Canada are now seasonal conservation areas. Furthermore a 70,000 square mile area of the Bering Sea has recently been identified as critical habitat in the North Pacific, and may receive protection as a result.

Status : CITES - Appendix I. IUCN ; Endangered