Characteristics of Marine Mammals

Class Mammalia Give birth to live young Give birth to live young Fur/hair Fur/hair Produce milk to feed young Produce milk to feed young Warm blooded Warm blooded

Categorization 1. Order Sirenia – manatees and dugongs 2. Order Carnivora – sea otter and polar bear 3. Order Pinnipedia – seals and sea lions 4. Order Cetacea – whales/dolphins

Marine Mammals Categorized by time spent in the water Categorized by time spent in the water All very streamlined All very streamlined Modified for water movement Modified for water movement

Approximately how much time does a mammal need to spend in the water to be classified as marine? A. 25% B. 50% C. 75% D. 100%

Which of the following are reasons that mammals can be classified as marine? A. Rely on the ocean for prey B. Rely on the ocean for reproduction C. Anatomy adapted to fit a marine lifestyle D. All of the above

Swimming and Diving Pinnipeds move by flippers Pinnipeds move by flippers Cetaceans and Sirineans use tail fluke Cetaceans and Sirineans use tail fluke UP AND DOWN!!! UP AND DOWN!!!

Which order that includes marine mammals is least adapted to a marine lifestyle? A. Sirenia B. Carnivora C. Pinnipedia D. Cetacea

Adaptations for Diving 1. ↑ concentration of hemoglobin  ↑ absorption O 2 2. Hyperventilate before dive/ some exhale 3. Slow heart rate/cut off blood flow nonessentials 4. Thicker veins/arteries 5. Collapsible lungs

Behavior Highly social w/ complex group organization and dynamics Highly social w/ complex group organization and dynamics Pair bonds, hierarchy, changing dynamics Pair bonds, hierarchy, changing dynamics Relationships may last days or years Relationships may last days or years

“Play”/Exploratory Behavior Use objects – food, branches, toys, garbage Use objects – food, branches, toys, garbage Breaching Breaching Spyhopping Spyhopping Bow riding Bow riding Corralling Corralling Intimidation/rough-housing Intimidation/rough-housing Kidnapping Kidnapping Rape Rape

Behavior Bubble feeding Bubble feeding Example - humpbacks Example - humpbacks Hunting coordination Hunting coordination Example - orcas Example - orcas Hunt as a pack – coordinate/use vocalizations Hunt as a pack – coordinate/use vocalizations Lower frequency than Lower frequency than prey hearing prey hearing

Behavior Stranding/beaching Stranding/beaching Accidental Accidental Disease/confusion/disorientation Disease/confusion/disorientation Purposeful Purposeful Hunting – dolphins/orcas Hunting – dolphins/orcas

Migration Thousands of miles Thousands of miles Usually between Usually between breeding grounds and breeding grounds and hunting grounds hunting grounds Gray whale is the Gray whale is the longest migration longest migration Populations remain Populations remain distinct distinct

Human Impact Current research Current research Missing tons info Missing tons info Negative impact populations – whaling/hunting Negative impact populations – whaling/hunting Use as behaviorists – Use as behaviorists – Navy, rescue diving, object retrieval

Which of the following behaviors are related to finding food? A. Bubble feeding B. Bow riding C. corraling D. breaching

Which of the following behaviors demonstrates the strength of relationships between individuals? A. corralling B. breaching C. Playing with toys D. Bubble feeding

Why do marine mammals migrate? A. To find food B. To give birth C. Both a and b D. Neither a and b