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

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
   

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.