Do Now #6 What are some of the behaviors that you have seen cetaceans do? What parts of their bodies allow them to do those behaviors?

Cetacean Anatomy & Behavior EQ: What adaptations do cetaceans have?

Anatomy

Adaptations Large, steam-lined body Almost entirely hairless Contain a thick layer of fat called blubber Blowhole on top of head for air exchange – Connects directly to the lungs – Muscles control when it opens and closes Drink salt water

Adaptations Some species make very deep dives in search of food – Use oxygen more efficiently & have more red blood cells to hold it – Decrease heart rate & redistribute blood – Most will only stay under for min but can stay under for ~40 min – Sperm whales can dive to depths over 1000m for hours Fast swimmers – Powerful muscles running nose to tail – Orca is the fastest at 30 mph

Sensory Abilities Large brains – Brain-to-body size second only to humans Use sound communication – Produce unique whistles with pod dialects based on geographic location Some species use sound to identify objects known as echolocation Eye sight is as good underwater as out of the water DolphinHuman

Echolocation Evolved for toothed whales in murky waters A series of high frequency clicks are made in the airway below the blow hole Bounce the sound off their mouth bones and focus them using their melon Receive sound through their lower jaw

Intelligence Social structure revolves around groups called pods – Communicate, have hierarchies, work together to hunt & raise young Play – Jumping, bubble rings & surfing Creativity – Develop new, unusual responses to changing situations Tool Use – Use sponges to protect noses while foraging in the sand Cross-species Cooperation – Have helped other whale species as well as humans – Learn behaviors from humans

Intelligence

Migrations Only done by some whales Seasonal move from areas of cold (summer) to warm water (winter) to to mate & give birth Cold waters have abundant food Warm waters are more conducive to raising young Gray whales migrate the longest traveling 10,000-12,000 miles round-trip Use ‘sonar’, currents & magnetic field to guide migrations

Reproduction Reproduce every 2-7 years depending on species All reproductive organs are internal until needed – Helps them stay streamlined Often male competition for breeding partners Give birth to a single, live young after a year gestation Care for their young for several months to several years

Populations Whales live from years – Dolphins: years – Humpbacks: ~40 years – Fin & Blue: 80+ years Many population numbers are rebounding from depletion by whalers – Toothed whales are least endangered – Most baleen whales are endangered – River dolphin are most endangered – Some are so rare to see we cannot accurately count their numbers

Whales of NJ Most commonly seen are: – Humpback – Finback – Bottlenosed dolphin Other species include sperm, sei, blue, and right whales and Atlantic white sided, common and Risso’s dolphins

Test Tomorrow! Cram sheet due tomorrow Notebooks: 6 Do Nows Salinity Notes – Salinity – Changes in Seawater Cetacean Notes – Classification & Evolution – Anatomy & Behavior