Sperm Whales and Monodonts

Cetacean Family

  • Physeteridae
  • Monodontidae
     

Families and Species within this grouping

  • Physeteridae:  Sperm Whale (Physeter macrocephalus)
  • Monodontidae:  Beluga (Delphinapterus leucas), Narwhal (Monodon monoceros)
     

Physeteridae Defining Characteristics

  • Square assymetrical head (takes us 1/3 of body length)
  • Males can reach 60ft (18.3m) and weigh 125,000lbs (56,699kg). 
  • Females average 36 ft (11 m), 33,000 lbs (14,967 kg)
  • 36 – 50 large cone-shaped teeth in lower jaw, mainly in males
  • Blubber is nearly 14” thick
  • Hunt and navigate by echolocation
  • Eat squid, smaller squid, fish, sharks, crabs, octopus
  • Color ranges from dark gray, black, white (albino)
  • Communicate with patterned clicks
     
Sperm Whale
Sperm Whale
 
 
 
 
 
 
 
 
 
 
 
 
 

Interesting Facts

  • Dive depths of more than a mile
  • Can stay underwater for more than an hour
  • Pregnancy lasts 14 – 16 months
  • Interval between births is 5 – 7 years
  • Dive deeper than any other whale
  • Females do not dive as deep as males
  • The strongest social ties are between mothers and calves
  • Teeth don’t emerge until approximately 10 years of age
     

Habitat Range

  • Found in oceans worldwide
     

Threats to Survival

  • Humans
  • Entanglement
  • Collisions with boats
     

Life Expectancy

  • Maximum estimated expectancy is 77 years
     

Monotontidae Defining Characteristics
(Belugas and Narwhals)

  • Medium sized animals 13 – 19 ft (4 – 6m) in length
  • Weigh up to 3500 lbs (1600 kg)
  • No dorsal fin
  • Found in high latitudes
  • Travel in groups
  • Feed near the bottom
  • Feed on fish, squid, crustaceans, octopi, worms
  • White to white – gray coloring
  • Very vocal with others of their species
  • Approximately 5 ft (1.3m) at birth
     
“Two Views, Narwhal and Shark”
William Scoresby. NBWM Kendall Collection
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Habitat Range

  • Arctic Ocean
  • Freshwater rivers that empty into the Arctic
     

Threats to Survival

  • Orcas
  • Polar Bears
  • Pollution
  • Humans
     

Life Expectancy

  • Estimated 25 – 50 years
     

Beluga (Delphinapterus leucas)
Interesting Facts

  • Tiny eyes
  • Rounded melon
  • Thick blubber
  • Well-defined neck
  • No neck vertebrae are fused together
  • Wide, deeply notched flukes
  • Short, round, wide flippers
  • Have 34 teeth designed to grab and tear prey
  • Teeth are found in upper and lower jaws
  • Belugas do well in captivity/being observed by humans
  • Usually dive about 3-15 minutes while diving for food
  • Can dive a depth of about 1,300 – 2,100 feet (396 – 640 m)
  • Make clicks, squeals, chirps, grunts, screeches and whistles
  • Pregnancy lasts 14 – 16 months
  • Births take place every 2-3 years
     
 
 
 
 
 
 
 
 

 
Photo by latimesblogs.latimes.com
 
 
 
 
 

 

 

 

 

 

Narwhal (Monodon monoceros)
Interesting Facts

  • White with green and brown spotting
  • Become white in old age
  • All narwhals have 2 teeth in their upper jaw
  • After the first year of a male narwhal's life, its left tooth grows outward, spirally, through the face
  • Tooth can be 7-10 feet (2-3 m) long
  • Tusk used for males to fight and show dominance
  • 3% of males will have two tusks
  • 3% of females will grow a tusk
  • Some groups consist of just one sex and others contain both sexes
  • Many pods may travel together, forming very large groups
  • Rely on sound production and reception to navigate, communicate, locate breathing holes, and hunt in dark or murky waters
  • Make squeals, clucks, mews, chirps, trills, and bell-like tones
  • Can dive down to 1500 m deep
  • Duration of a narwhal dive is from 7-25 minutes
  • Pregnancy lasts 10 – 16 months
  • Births take place every 3 years
     
Narwhal
 
 
 

 

 

 

 

 

Narwhal

 

 

 

 

 

 

Cited Sources

  • http://www.enchantedlearning.com/subjects/whales/species/Beluga.shtml
  • http://www.vanaqua.org/learn/aquafacts/cetaceans/belugas
  • http://jason-parent.suite101.com/the-alaskan-beluga-whale-an-endangered-species-a147568
  • http://library.thinkquest.org/3500/Narwhal.html
  • http://www.enchantedlearning.com/subjects/whales/species/Narwhal.shtml
  • http://www.enchantedlearning.com/ngifs/Narwhal_bw.GIF
  • Cox, Vic. Whales & Dolphins. S.l.: Book People, 1990. Print.
 
Researched and written by Sharmaine Flint, NBWM Apprentice, March 2012