denise
08-12-2008, 04:58 PM
Dolphins are the most recognized, well known, and well loved, of all marine creatures. There are almost 40 species worldwide. As mammals (like us), dolphins are air breathers, and use their single blowhole on top of their head to exchange gases with. During each breathe, dolphins exchange more than 80% of its lung air, this is much more efficient than humans, who exchange only about 15% of their lung air with each breath. Dolphins need to breathe every 2 minutes, but can hold their breath for up to several minutes if necessary. However they can dive deeper in search of food, to more than 1200 feet! Dolphins have special physiological adaptations to allow them to dive deep successfully. Their heartbeat slows down significantly while they are diving. Blood is shunted away from non-essential tissues, out to essential organs such as the heart, lungs, and brain, where oxygen is needed.
http://www.dayo.com/images/forum/dolphinsdebbie_3.jpg
Photo by Debbie Buck
As excellent swimmers, home is anywhere in the shallow seas of the continental shelf, where they feed on an ample diet of fish and squid. Dolphins use echolocation, to sense and track prey, they emit a series of high-pitched clicks and use the rebounding click to tell them where objects are. Dolphins live in small groups called pods.They are very social and intelligent animals, exhibiting a friendly appearance and playful attitude.
http://www.scubadiver.cc/fishid/dolphinpod_1.jpg
Dolphins have few natural enemies because of their bulk and size. For some smaller species of dolphins, larger sharks are a risk, especially to calves. Despite their endearing and trusting nature, dolphins have suffered at the hands of humans. Habitat degradation and pollution are serious concerns, notably from pesticides, heavy metals, and oil. Injuries and deaths due to collisions with boats, are also common. Large numbers of dolphins are killed as bycatch, from the indiscriminate use of drift and gill nets. Up until recently dolphins were/are still killed for meat and oil. The Amazon River Dolphin, and the Ganges and Yangtze River Dolphin are now seriously endangered.
Worldwide, there are a large number of rescue organizations and sanctuaries for the care and rehabilitation of sick, wounded, stranded or orphaned dolphins. These play a very important role in dolphin conservation and welfare. These organizations do very good work, and receive lots of public attention and finances, and recent conservation efforts have greatly reduced the number of dolphin mortalities. However it is important to remember that dolphins are not the only endangered species crying out for help, many other less endearing, but equally in need species, are in dire need of help.
Several dolphin species occur in Florida coastal waters. The most common of these is the bottle-nosed dolphin Tursiops truncatus. Around Florida, bottlenose dolphins usually live in coastal waters to a depth of 15 to 150 ft. Due to their proximity to land, they are especially affected by pollution, heavy boat traffic, habitat destruction, and competition with fisheries.
http://www.scubadiver.cc/fishid/adolphin.jpg
Bottlenose Dolphin, Tursiops truncatus, Florida
http://www.scubadiver.cc/fishid/dolphinsfreedigitalphotos_1.jpg
Bottlenose dolphins
Photo by Jay (http://www.freephotos.com/index.php?action=view_member_photo&view_memberid=jay)
http://www.scubadiver.cc/fishid/dolphins1bob.jpg
Pod of bottlenose dolphins
Photo by Bob Rosell
http://www.dayo.com/images/forum/dolphinsdebbie_3.jpg
Photo by Debbie Buck
As excellent swimmers, home is anywhere in the shallow seas of the continental shelf, where they feed on an ample diet of fish and squid. Dolphins use echolocation, to sense and track prey, they emit a series of high-pitched clicks and use the rebounding click to tell them where objects are. Dolphins live in small groups called pods.They are very social and intelligent animals, exhibiting a friendly appearance and playful attitude.
http://www.scubadiver.cc/fishid/dolphinpod_1.jpg
Dolphins have few natural enemies because of their bulk and size. For some smaller species of dolphins, larger sharks are a risk, especially to calves. Despite their endearing and trusting nature, dolphins have suffered at the hands of humans. Habitat degradation and pollution are serious concerns, notably from pesticides, heavy metals, and oil. Injuries and deaths due to collisions with boats, are also common. Large numbers of dolphins are killed as bycatch, from the indiscriminate use of drift and gill nets. Up until recently dolphins were/are still killed for meat and oil. The Amazon River Dolphin, and the Ganges and Yangtze River Dolphin are now seriously endangered.
Worldwide, there are a large number of rescue organizations and sanctuaries for the care and rehabilitation of sick, wounded, stranded or orphaned dolphins. These play a very important role in dolphin conservation and welfare. These organizations do very good work, and receive lots of public attention and finances, and recent conservation efforts have greatly reduced the number of dolphin mortalities. However it is important to remember that dolphins are not the only endangered species crying out for help, many other less endearing, but equally in need species, are in dire need of help.
Several dolphin species occur in Florida coastal waters. The most common of these is the bottle-nosed dolphin Tursiops truncatus. Around Florida, bottlenose dolphins usually live in coastal waters to a depth of 15 to 150 ft. Due to their proximity to land, they are especially affected by pollution, heavy boat traffic, habitat destruction, and competition with fisheries.
http://www.scubadiver.cc/fishid/adolphin.jpg
Bottlenose Dolphin, Tursiops truncatus, Florida
http://www.scubadiver.cc/fishid/dolphinsfreedigitalphotos_1.jpg
Bottlenose dolphins
Photo by Jay (http://www.freephotos.com/index.php?action=view_member_photo&view_memberid=jay)
http://www.scubadiver.cc/fishid/dolphins1bob.jpg
Pod of bottlenose dolphins
Photo by Bob Rosell