Category Archives: Features & Fun Topics

Dolphins

Dolphins have a very special place in my heart and spirit.  I think I meet a soul when I encounter a wild dolphin. There is a special “connection.” Dolphins are referenced back to the writings of Aristotle and had a mystical importance during ancient Greek and Roman eras.  Dolphins, whales, and porpoises are all cetaceans and there some 80 recognized species throughout the world. Dolphins are toothed whales – Odontocetes.  Like all whales, they are highly intelligent. Dolphins live in highly functioning social family groups and are sentient beings.

Like many animals that call our oceans home, dolphins face many human threats: ocean pollution, oil spills, mercury poisoning, acoustical pollution, indiscriminate killing from commercial fishing fleets, and their outright slaughter in such places as Taiji, Japan. If you want more information on the “dark side” of what is happening to dolphins and whales around the world, I suggest viewing:  the Oscar winning documentary The Cove (The Cove), HBO’s Blackfish (Blackfish), and Sonic Sea (Sonic Sea). There are numerous marine organizations dedicated to preserving our planet’s oceans and the amazing species that live in our oceans. I will provide a list of these outstanding organizations in a future posting on my website.

Dolphins do not belong in marine parks or aquariums.  In the wise words of Jacque Cousteau, “no aquarium, no tank in a marine land however spacious it may be, can begin to duplicate the conditions of the sea.  And no dolphin who inhabits one of those aquariums or one of those marine lands can be considered normal.”

If you have the opportunity to snorkel with wild dolphins, this experience will be something that you will never forget.  And, hopefully it will be an encounter established on conditions set by the dolphins.

Dolphin Gallery

 

 

 

 

 

 

 

 

 

 

 

 

Sharks

I’ve had the wonderful experience of diving and observing sharks on many of my diving destinations.  Sharks are truly a magnificent and graceful fish.  They are a critical keystone predator in the ocean ecosystem.  Unfortunately, sharks are under attack and being slaughtered indiscriminately and brutally.  Sharks have lived in our oceans for over 500 millions years.  Today, many species are in danger of extinction.

Please view my gallery to a view my shark photos.  For more extensive information on sharks, I refer you to a former diving buddy’s website.  Katherine Cope has created an excellent website that gives more detailed information on sharks as well as information on conservation groups trying to educate the world on their importance, their preservation, and the great threats facing throughout the world: Sea Sights International

Sharks Gallery

 

Symbiosis

Symbiotic relationships are as fascinating as they are critical to the survival of all living organisms.  Symbiosis literally means “with living” and occurs when two different living species live together in a very close relationship.  Life on Earth would not exist without symbiotic relationships.  Symbiotic relationships exist in three forms:  mutualism, commensalism, and parasitism.  In symbiotic relationships there is a host organism and an organism that chooses to live or hang out with a host.  This organism is called the “symbiont.”   So, in all symbiotic relationships, we refer to either the “host” or the “symbiont.”

 

In mutualistic relationships, both the host and symbiont benefit and help each other to survive and stay healthy.  Marine examples include anemonefish (clown fish) living with their host anemone and cleaning stations where cleaner shrimp and fish remove parasites from larger fish.  Anemonefish nestle, breed, and live in the poisonous tentacles of their sea anemone.  The anemonefish have built up immunity from the stinging cells (nematocysts) on the anemone’s tentacles, but other fish and small prey are not immune. In return for protection and safety from predators, the anemonefish actually help take fish that have been killed by the anemone’s stinging cells and feed its host anemone.  In other examples of mutualism, large fish will actually swim into a marine “cleaning station” and become very still.  These fish then attract small shrimp and cleaning fish that remove small parasites from the inside of the gills and mouth of the large fish.  In all these examples of mutualism, both organisms – the host and the symbiont – mutually benefit and help each other.

 

Commensalism is seen a bit more rare.  This is where the symbiont benefits and the host is mostly unaffected and not harmed.  A classic marine example of commensalism is seen when remoras swim under and/or attach themselves to a host shark with their head plate.  The remoras may be a nuisance for the shark, but the shark is neither harmed nor helped by the remoras.  The remoras, on the other hand, are in a prime location to grab scraps from prey eaten by the shark.  The remoras stay just out of the shark’s reach. Another example is a remora that has attached itself with its head plate to the shell of a turtle.  I don’t think the turtle particularly likes the remora, but it neither harms nor helps the turtle.  Favorite food sources for many turtles are sponges.  You can often see angelfish hanging out with a turtle as it rips off pieces of sponge from the reef – the angelfish are then able to pick up uneaten small pieces of sponge that float their way.

 

Parasitism is not such a good relationship for the host. Parasites (symbiont) such as worms and isopods always benefit from their relationship with their host, but parasites can cause great harm and even kill their host.  The butterfly fish swimming with the isopods on and around its eyes certainly is not beneficial for the butterfly fish or the grouper.  Like humans and other animals, worms and intestinal parasites have deadly implications.

 

The examples below illustrate the three kinds of symbiotic relationships described above.

 

 

Symbiosis Gallery

Invasive Lionfish

The lionfish is elegant, majestic, and invasive!   Lionfish live in balance with nature in the coral reefs of the Indo –Pacific and are a prize subject for photographers. Lionfish have venomous spines – their zebra like strips serve as a warning to predators to stay away and avoid contact. Contact with their venomous spines cause extreme pain to humans.
It is not clear how lionfish were introduced to waters of the Caribbean and Atlantic, but lionfish have invaded these waters at an alarming rate. The most common of these lionfish is the red lionfish – Pterois volitans. Without any natural predators, lionfish have the potential to wreak havoc on the natural balance of the fish populations. They have voracious appetites, reproduce at an alarming rate, and have no natural predators.

The new thinking about this lionfish invasion goes something like this: IF YOU CAN’T BEAT THEM, EAT THEM! Lionfish are now features of cookbooks, restaurants, and fish derbies. Reef.org, a Florida non-profit marine conservation organization, has published The Lionfish Cookbook by Tricia Ferguson and Lad Akins. Many dive operations in the Caribbean are now training and putting a spear gun in the hands of willing divers to help control the lionfish invasion. I recently discovered that lionfish ceviche is quite delicious!

Nudibranchs

Nudibranchs are marine slugs!  They are members of the mollusk phylum and gastropod class.  They and are found mostly in shallow tropical waters and there are some 3,000 known species. They are usually quite small (6 mm) and many display an amazing array of colors.  Nudibranchs feed on sponges, hydroids, corals, bivalves, and even other nudibranchs!  Many nudibranchs are toxic – some members have the unique ability to incorporate defense mechanisms from the prey that they eat:  nematocysts (stinging cells) from hydroids and toxins from sponges can become part of the nudibranch’s defense mechanisms. Nematocysts from consumed prey such as hydroids, anemones, and coral are found on the tentacles of the nudibranchs. Many members get their color from the prey that they eat.

Nudibranchs come from the scientific name Nudibranchia.  This literally means naked gills.  They can be distinguished by rhinophores on the top of their head.  Nudibranchs are also hermaphrodites – that is, they can reproduce with both sexes of the species.

If you like looking for small critters, finding a nudibranchs on a dive is a definite treat.  But, make sure you have a macro lens on your camera!

Yellowhead Jawfish with Eggs

The Yellowhead jawfish (Opistognathus aurifrons) is a mouthbrooder – a paternal mouthbrooder. The male Yellowhead jawfish incubates his offspring’s eggs in his mouth until the eggs hatch and the juveniles are large enough to free swim.  Jawfish burrow holes in sandy and rubbled areas and make their homes by excavating sand and rubble with their mouth.  If you are patient and very still, you will see them stick their heads out of their burrow and swim up vertically and hover above their sandy home.  The Yellowhead is found throughout the Caribbean in shallow waters.  They are pale in color with a yellow head – hence their name:  the Yellowhead!   It was a thrill to finally see a male Yellowhead with his eggs in Little Cayman on Three Fathom Wall.  It would be fun to observe the Yellowhead with his eggs over a period of days and see the actual release of the juveniles.