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Dolphins,
Porpoises and
Whales are included in the Order
Cetacea. They are mammals fully adapted to marine life and are divided
into two suborders, Mysticet (baleen whales: including blue,
humpback, gray, bowhead, minke and right whales) and Odontoceti
(toothed whales: including killer whales or orcas, beluga whales,
narwhales, sperm whales, dolphins and porpoises). There are 81
known species, 12 of which are on the Endangered Species list (see
thumbnailed images above). Cetaceans are
relatively large animals, characterized by fusiform, streamlined bodies
that glide easily through the water. They are nearly hairless and are
insulated from cold water by a thick layer of blubber.
Dolphins and Porpoises
belong to the families Delphinidae and Phocoenidae, with the dolphins
the largest and most diverse family, one that includes 26 species.
They possess a distinct beak and most species of dolphins are larger
than porpoises. Porpoises belong to a rather small family which consists
of only six species. They have no distinct beak and their foreheads
slope uniformly to the tip of their snout. Both types of cetaceans are
carnivores, and their sleek streamlined shapes are perfectly adapted to
high speeds in the ocean. Bursts of up to 25 miles per hour have been
recorded. Dolphins and porpoises are able to achieve such high speeds
by leaping from the water in a series of dives and spending as little
time as possible under the water, a technique known as "running".
The life cycle of dolphins
and porpoises is similar to that of other cetaceans, and they bear their
young alive. Nursing lasts between one and a half to two years,
and the mother will remain with her calf for a period between three and
eight years. Most species tend to bear one calf every other year,
and dolphins and porpoises have an average life expectancy of
around thirty years.
Dolphin and porpoise brains
are about the same size as humans, and they possess an amazing ability
to learn and imitate. Much has been written about their intelligence and
the consensus in the scientific community is that have a level of
intelligence compare to humans. In hunting for prey, dolphins and
porpoises use their developed sense of hearing in a very
sophisticated way known as echolocation, a process whereby they
emit a steady series of rapid "clicks" through their blowholes. These
outgoing clicks bounce off objects, similar to radar, and a
portion of the signal is reflected back to the dolphin for analysis.
Through this process, they are able to determine the distance to a
school of fish or other prey by measuring the time between emitting and
returning clicks. This allows these amazing animals to hunt prey over
great ranges in which visibility is limited. Dolphins feed mainly
on schools of prey and as a result most species have developed
cooperative hunting practices which are much more efficient than hunting
alone.
Another phenomena associated with many
whales, especially the Blue Whale and the Humpback Whale, are the
haunting songs they sing. Researchers are not sure why whales sing,
although it is thought their singing is associated with breeding, and
keeping in contact with each other over vast ocean distances.
Whales are the
largest animals that have ever lived on earth, including the dinosaurs.
The largest is the blue whale, which can grow to almost 100 feet in
length, the height of a 9-story building. These enormous animals eat
about 4 tons of tiny krill each day, obtained by filter feeding through
their baleen. The
smallest is the dwarf sperm whale which grows only to just over 8 feet
long.
Whales exhibit a number of
unusual and characteristic behaviors -breaching, spyhopping, lobtailing and
logging. Breaching is jumping high out of the water and then slapping
the water as they reenter. Occasionally they twirl around while
doing this spectacular move. In spyhopping the whale pokes its head out of the water and
turns around, perhaps to look. Some whales also stick their tails out of
the water, swing it around and then slap the water's surface with it.
This is known as lobtailing. It may be done as a warming to the rest of
the whale group, or pod, as a warming. Logging is resting on the surface
of the water, with the tail hanging beneath. While floating motionless
like this, part of the whale's head, dorsal fin and back are exposed.
Cetaceans exhibit very
strong social ties, with the strongest being between the mother and
calf. A social group of whales is referred to as a pod. Mysticet (baleen whales)
travel alone or in small pods, and Odontoceti (toothed whales,
which include dolphins and porpoises) travel in large, frequently stable
pods. These toothed whales also hunt their prey in groups, migrate
together and share care of the young.
The links below will take you to
some great websites about cetaceans.
The best sites to start for general information are marked with a
star
 .
If you have a site that you think should be listed,
please
email me.
Official, Scientific & Governmental Sites
Endangered
Species Organizations
Cetacea
Conservation Groups
Other
Countries
Cetacea
Species
Cetacea
Observation & Eco-Tours
Commercial
& Research Facilities
Miscellaneous
Personal
Websites
Mass Extinction of Species
The Alliance of Marine Mammal Parks and Aquariums
The
Alliance of Marine Mammal Parks and Aquariums is an international
association representing marine life parks, aquariums, zoos, research
facilities, and professional organizations dedicated to the highest
standards of care for marine mammals and to their conservation in the
wild through public education, scientific study, and wildlife
presentations.
Discovering Whales
General information
website with pages on different whale species.
Marine Mammal Commission
The Marine Mammal Commission is an
independent agency of the U.S. Government, established under Title II of
the Marine Mammal Protection Act. It was created to provide independent
oversight of the marine mammal conservation policies and programs being
carried out by the federal regulatory agencies.
National Marine Mammal Laboratory: Whales, Dolphins and Porpoises
General information on cetaceans
NOAA's Office of Protected Species: Whales, Dolphins and Porpoises
General information
WDCS Whale and Dolphin Conservation Society
WDCS, established in 1987, the
Whale and Dolphin Conservation Society is the world's most active
charity dedicated to the conservation and welfare of all whales,
dolphins and porpoises.
Welcome To The Watery World Of Whales
General information
Whale Center of New England
Their mission is to
contribute to the conservation and protection of marine mammals and
their habitats.
WhaleNet
Wheelock College interactive educational website
that focuses on whales and marine
research.
Whales Online
Whales-online is an information
site dedicated to the conservation of whales, dolphins and porpoises in
the Southern Hemisphere.
Wild Animal Watch: Dolphins
Scholastic website for educators on dolphins
ICUN World Conservation Union
The World Conservation
Union is the world’s largest and most important conservation network.
The Union brings together 82 States, 111 government agencies, more than
800 non-governmental organizations (NGOs), and some 10,000 scientists
and experts from 181 countries in a unique worldwide partnership. The
Union’s mission is to influence, encourage and assist societies
throughout the world to conserve the integrity and diversity of nature
and to ensure that any use of natural resources is equitable and
ecologically sustainable.
United Nations Environment Programme World Conservation
Monitoring Centre
The
United Nations Environment Programme
World Conservation Monitoring Centre (UNEP-WCMC) is the
biodiversity assessment and policy implementation arm of the United
Nations Environment Programme (UNEP), the world's foremost
intergovernmental environmental organization.
US Fish & Wildlife Webpages on Endangered Species
The American endangered
species list maintained by the US Fish & Wildlife Service
Word Conservation Union ICUN Red List of Endangered Species
IUCN
- The World Conservation Union, through its Species Survival Commission
(SSC) has for four decades been assessing the conservation status of
species, subspecies, varieties and even selected subpopulations on a
global scale in order to highlight species threatened with extinction,
and therefore promote their conservation.
ANON -Act Now For Ocean Natives
Dedicated to protecting
whales and other cetacea in our oceans.
American Cetacean Society
The ACS protects whales, dolphins,
porpoises and their habitats through public education , research grants
and conservation actions. Founded in 1987, the American Cetacean Society
is the oldest whale conservation group in the world.
Cetacean Society International
CSI is an all volunteer,
non-profit conservation, education, and research organization based in
the USA, with volunteer representatives in 26 countries around the
world. The goal of the Cetacean Society International is to achieve on a
global basis the "optimum utilization of cetacean resources"
through benign utilization and the elimination of all killing and
captive display of whales, dolphins, and porpoises.
Save The Whales
Save The Whales,
founded in 1977, is dedicated to educating children and adults about
marine mammals, their environment and their preservation.
Surfers For Cetaceans
Surfers For Cetaceans is
a call to surfers everywhere in the world to take action on behalf of
the whales and dolphins of the world, of Mother Ocean.
The Oceania Project: Caring For Whales, Dolphins & The Oceans
The Oceania Project, established
in 1988, is a not-for-profit, research and education organization
dedicated to raising awareness about Cetacea and the ocean environment.
The Original Dolphin Project
Founded on Earth Day
1970, for over 30 years The Dolphin Project has worked to stop the
capture and confinement of dolphins worldwide.
CANADA, BRITISH COLUMBIA
Wild Whales
A project of the
Vancouver Aquarium's Marine Science Center. Focus on British Columbian
whales.
IRELAND
Irish Dolphins.com
Irish Dolphins.com is dedicated to
giving accurate information about 'friendly' or sociable wild dolphins
(and whales) around the coastal waters of Ireland.
BOTTLENOSE
DOLPHINS:
Seaworld
Seaworld website that focuses on Bottlenose dolphins.
HUMPBACK WHALES:
Nature.org:
Humpback whales
PINK RIVER
DOLPHIN:
Pink River Dolphin
Personal journal website
about the Amazon River pink dolphins
Aquatic Adventures
Worldwide
expeditions for swimming with whales and dolphins
Whale Watch.com
Commercial whale
watching company out of Rhode Island. General information and
links, excellent resource site for whale watching.
Whale Watching Web
Links to whale
watching websites all over the world. A great whale watching site.
Dolphins Plus
Dolphins Plus is a dolphin
research and education facility in Key Largo, Florida. Dolphins Plus
houses 14 Atlantic Bottlenose Dolphins and 2 California Sea Lions.
Dolphin Research Center
The Dolphin Research
Center, located in the Florida Keys, is not-for-profit research and
facility, home to Atlantic Bottlenose dolphins and California sea lions.
Aqua Thought Foundation
Private research
site dedicated to the exploration of human-dolphin interaction.
Charlotte, The Vermont Whale
Interesting website dealing with
the bones of a whale found in a Vermont.
Dolphins and Man......Equals?
Online article by
Regina Blackstock that examines dolphin intelligence.
Earthtrust Hawaii's Marine Wildlife: Dolphins
Educational website geared for HS
and MS students.
Marine Mammal Stranding Center
Dedicated to the rescue,
rehabilitation and release of marine mammals and sea turtles.
NOAA's Office of Protected Species: Protect Dolphins Campaign
NOAA Fisheries website
-general information about dolphin protection for general public.
Songs of the Whale
Some excellent sound recordings
Whale Songs
Educational resource
site with focus on whale songs.
David's Whale & Dolphin Watch
Personal website
with very large collection of whale and dolphin photographs>
William A. Levinson's Marine Mammals: Dolphins and Whales
General information
American Museum of Natural History Statement
The IUCN Red List of Endangered Species
Professor David Ulansey's Website -Mass Extinction Underway
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