Nudibranch The Jewels of the Sea

Nudibranchs are such beautiful little creatures with fantastic coloration and color patterns that they do not deserve to be called a sea slug. I think they look more like jewels of gems of the sea. Soft bodied and slow moving, these mollusks lack an external shell, so their external gills are exposed, which gives them their name. Nudibranch literally means naked gills. As Nudibranchs evolved, they lost their shell while developing other defense mechanisms. Their bodies may resemble the texture and color of their surroundings giving them the need camouflage. Others, such as the Chromodiris family of Nudibranchs, have bright vivid coloring warning of their distasteful or poisonous skin. Most Nudibranchs are small, an inch or less, with the largest being about twelve inches. I have seen striped, poka dot, bright blue to bright pink, and a stunning variety of colors, patterns, and shapes. There are over 1, 000 described species of Nudibranchs and new ones are being found continually.

Nudibranchs are found in oceans around the world, but are most prolific in warm, shallow, sea water. Their physical forms are quite varied but all have tentacles called cerata on their heads which allows them to feel, smell, and taste.

Nudibranchs rely on the “you are what you eat” principal. Nudibranchs are carnivorous, feeding on sponges, hydroids or bryozoans, and some will feed on other Nudibranchs. Other groups will feed on tunicates, barnacles, or anemones. On some occasions Nudibranchs are cannibals and will prey on members of their own species.

Nudibranch

When Nudibranch feed on hydroids, anemones, and jellyfish, they are able to store the toxins for their own use by storing them onto the areas of their bodies and discharging the toxins and stingers later as needed for protection. Nudibranchs do not digest the stinging cells but pass them on, imbedded into little sacks which they store onto their backs.

The ocean is such a large place which can make it difficult for such a small creature to find a mate so Nudibranches are able to increase the odds of reproducing. Nidibranchs are hermaphroditic which means they are both male and female at the same time. They each carry both eggs and sperm and cross fertilize each other. Nudibranchs are able to mate with any mature individual of the same species. After the mating process, both Nudibranchs will lay their own eggs within a colorful gelatinous spiral. Because Nudibranch genetalia have the same tube like structure encasing both the eggs and sperm, this makes it almost impossible for a Nudibranch to fertilize themselves. Their life spans vary from one short month to about a year.

Nudibranchs cannot be taken from the reef and made into aquarium pets because they lose their shape and coloration. This keeps them from being harvested for the aquarium industry. The best way you can take home one of these beautiful jewels is to take a picture on them in their natural habitat and enjoy!

Swimming with Ghosts

                                            Swimming with Ghosts

Diving is full of surprises, especially the Indo Pacific. New species of fish and marine life are being discovered on a regular basis in this underwater paradise. Even though divers come prepared to look for the many fish known to be in this area, finding them can sometimes be a difficult task. One of the most difficult fish to spot is the Ghost Pipe Fish. They are masters at camouflage, hiding among crinoids, plant life or mimicking sticks, sea grass, and other underwater vegetation, depending on the species. This ability to camouflage themselves in their underwater habitat, puts them on the list of creatures for whom divers search.  

Ghost Pipefish are sexually dimorphic so the male and female are easily distinguishable. The male is about ½ the size of the female. During breeding season, the Ghost Pipe Fish will change their color and their shape to camouflage themselves even better.

The Ghost Pipefish belong in the same family as the Sea Horse, but unlike the Sea Horse, the female Ghost Pipefish harbors the eggs in her pouch, instead of being carried by the male. Ghost Pipefish are an external skin-brooding species, which means the eggs are enclosed into a pouch and attached inside. This only occurs on the inside surface of the pelvic fins of the females and they are the brooders in this species. The female’s pelvic fins are larger than the males and the female is also larger than the male. The female’s pelvic fins are expanded and connect to the body and to each other to form a brooding pouch.  She will fan the eggs by opening and closing her pelvic fins. The females will carry the eggs in this pouch during the incubation period. This allows the female to move the babies to a protected site for survival and also decreased the risk of them being eaten during the developmental stage. A normal brood size may be up to 350 babies. The young are expelled from the pouch at birth. The small babies start out as larvae, drifting in the ocean currents as maturity is gradually reached. They will then settle on the ocean floor, transparent in color, until it finds its way to the reef to reproduce. At this stage, the Pipefish will now take on shape and color, camouflaging itself on the reef.  Ghost Pipefish will find a mate and pair off in a union that can be observed for many days. Once fertilized the cycle repeats itself.        

Ghost Pipefish grow to approximately five inches long and the float almost motionless, with their head and mouth facing downward, by floating around a similar background, they are almost impossible to see.  They feed on tiny crustaceans which they suck through their long snout.

The Ornate or Harlequin Ghost Pipefish are both colorful and distinctive. They are found living around crinoids, featherstars, gorgonian fans and black coral bushes.    Their coloring and body shape help them hide or stay camouflaged. The key to this ability to camouflage is the skin flaps that these fish use to mimic feathers.  Harlequin Ghost Pipefish can be found in shallow tropical and sub tropical waters near coral reefs, rocky drop-offs, or seaweed beds. They usually are found in depths of 9 to 75 feet. I found numerous pairs while diving in Bunaken, and many of the females were brooding babies. Their colors varied and included red, orange, black, and semi-transparent.  

                                                                                                                                                                                         

Robust Ghost Pipefish do not have the skin flaps of the Ornate Ghost Pipefish. Their bodies are elongated and mostly smooth, but they do have the distinctive pelvic fins like other Ghost Pipefishes.   I also saw many pairs of these fish on the reefs and near algae in the coral rubble vegetation off the coast of Bunaken, and in the muck at Lembeh Strait. Many of the females were brooding eggs in their pouches. They also float, or hover, almost motionless with their mouths facing downward. With smooth bodies, they resembled twigs or sea grass floating in the water and were easily missed by divers. With coloring in shades of light to dark brown, they can also be found in shades of grey to bright green. These are the largest of the Ghost Pipefish growing to a maximum length of 15 cm or almost six inches long. An exciting moment of my trip was finding a Red Robust Ghost Pipefish which is very rare to see.

Ghost Pipefish are so difficult to spot and are such an oddity that when spotted a large group of divers can be found surrounding and gawking at these little “Ghosts”.  They are typically a solitary species, but most of the ones we saw were paired with a mate, which may have indicated a mating season. . Even though these are not extremely rare to find on the reefs, their camouflage hides them so well that they are missed by most divers. During my trip, I saw many of each of these varieties, but because they “hide”, there is always a rush of adrenaline upon “bumping” into one of these ghosts that lurk in the reef and muck

Coral bleaching, pollution and destructive fishing methods are all a threat to the Ghost Pipefish. A further threat to their numbers is the home aquarium trade.        

                                                                                                                                                                                                                                                                                

Mandarin Fish

   

Mandarin Fish, (Synchiropus splendidus), are found in Malaysia, Indonesia, the Philippines, and Australia. I found these colorful jewels of the sea in the Northern Sulawesi diver’s paradise of Bunaken and the Lembeh Strait. These small fish (1 to 2 inches) are strikingly beautiful with their body designs of squiggles, swirls, dots, and stripes in bright colors of orange, green, blue, and yellow. Their name comes from the resemblance to the robes of Imperial Chinese officers known as mandarin. These beautiful fish are members of the dragonete family. Mandarin fish are dimorphic, which means they can accomplish the sexual and reproductive traits of either, if they lack mates of the opposite sex. The males typically have more orange color on their faces, and larger bodies, while the females have smaller dorsal fins. Even with their distinctive markings, mandarin fish are very difficult to locate in their native habitat.

Mandarin fish are difficult to locate because they are extremely shy. They live in pairs and in groups of up to five, living at depths of 4 to 60 feet . They prefer to live on fringing reefs and slopes, inhabiting broken coral rubble beds, in sheltered lagoons. Both movement and lights will scare them back into their coral habitat, which makes them very difficult to photograph. Because they are so shy, we arrived early to get into position, so that we were ready to photo when the action began and not scare them back into the reef. 

 Mandarin fish are elusive during the day, but if a diver is patient, they can be seen perched on or darting between coral branches. Swimming by rapidly pulsating their fins makes them appear to hover, much like a humming bird. Mandarin fish have a broad and depressed head. They have four dorsal spines, eight dorsal soft rays and no anal spines. The males are larger than the females and have an elongated first dorsal spine. Their big outward-set eyes are ideal for food hunting and feeding in the dim light conditions found underwater.

  The Mandarin Fish is one of the few types of fish who do not have scales. The fish are instead protected by a thick mucus-coated slimy and smelly skin. This coating helps protect them from parasites, and discourages predators because of their foul taste.  The bright, vivid coloration also serves as a warning to predators of their bad smell and taste. Not much is known about their predators, but scorpion fish have been known to lie in wait to attack an unsuspecting mandarin fish during their mating ritual.

                                                                                                                

Mandarin fish reproduce by releasing thousands of eggs into the ocean after a courtship consisting of a “mating dance.” The dance frequently is ended by the female before spawning has occurred, requiring several attempts to complete the process. This mating ritual occurs each evening before sunset.

Within twenty minutes of sunset every evening, three to five females will gather at a particular area of the reef. The males will visit, displaying courtship behavior, in hopes of attracting the females. The males are known to tour around to the different sites, mating with several females in an evening. The female will rest on the pelvic fin of the chosen male.  The pair will slowly raise about one foot up from the reef, belly to belly, and at the peak of their assent a cloud of sperm and eggs (around 200 eggs) are released into the water. The fish then disappear, instantly darting back into the coral. All of this takes place in a matter of seconds. A camera with low light capabilities will help when trying to capture the action. The fertilized eggs are spread by the current and will hatch in 18-24 hours. They hatch into larvae about one eight of an inch and will remain plankton for up to two weeks. Then they settle onto the reef and choose an appropriate habitat where they will reside. Mandarin fish are among the smallest ocean fish that spawn. An average life span is 10 to 15 years.

Because only a small number of females within a group are active, competition for the males is high. Females seem to prefer the bigger and stronger males and therefore the larger males mate more often than the smaller ones.  Because the smaller males don’t mate as often, they have been known to rush up on a mating pair releasing sperm in hopes of random fertilization.                  

After participating in a Mandarin dive, making the choice of sitting on the dock watching the sun set with a Pina Colada in hand or jumping in to watch the show was an easy one. If you are ever in an area where Mandarin Fish live, take the opportunity to see the beautiful colors and to watch the mating process. When you can find them, it is a good show. 

 

                 

Red Fox

 

I had the privilege of observing a fox family for a few days in the early April. The mom made her den near Lake Michigan at the top of a hill, in a heavily populated area. They are an attractive animal with a rusty reddish body, white underpants, chin, and throat, and a long bushy tail with a white tip. They have prominent pointed ears. The backs of ears, lower legs, and feet are black. The distinguishing feature which sets them apart from all other fox species is the white-tipped tail.  Their average height is 15-16” tall, 35-41” long and weigh between 8 and 15 pounds.

The Red Fox is very sensitive to low-frequency sounds, which sets it apart from most other mammals. The fox listens for underground noises such as digging, gnawing, and the rustling of small animals. When he detects these sounds, he will dig frantically into the ground or snow to capture the animal. He stalks its prey much like a cat, by moving in as close as possible, then running down the prey when it bolts. The Red Fox will continue hunting even if he is full, burying excess food under snow, leaves, or soft dirt. He appears to find his cache by memory and smell, although other animals sometimes find the cache first, before it is retrieved by the Red Fox. An adult fox usually does not retire into a den in the winter but will curl into a ball in the open and wrap its bushy tail around his nose and foot pads. At times he is blanketed by snow while in this position.

Adults remain solitary until mating season, which begins in late January or February with nocturnal barking. The maternity den is built shortly after mating and remains in use until late August when the family disperses. The den is then abandoned. The female will clean out extra dens for her family to use if disturbed, but the same one may be used for several years, which was the case with this mother fox, as she returned to the same den as last spring. Habitats range from mixed cultivated and wooded areas, and brush lands.

The maternity den is usually in sparse ground cover on a slight rise with a full view on all sides. It may also be on a stream bank, slope, rock pile, or the hollow of a tree log. The mail entrance is in an earthen mound, about 3’ wide with a mound of packed dirt. One to three less conspicuous escape holes are also built. This mother’s maternity den had one main entrance and five smaller escape holes. The den is well marked with excavated earth, cache mounds where they will bury their food, holes where food has been dug up, and scraps of bones, feathers, and fur.

While there were four kits with the mother fox, a Red Fox will have from one to ten kits born in March to May.  The kits are born in the maternity den after gestation of 51-53 days. When the kits are born, they already show the white tail tip. At about a month old, the young will play above ground, and will feed on whatever their parents will bring to them. Food is given by the mother to the first kit who begs for it. In years where food is scarce some young may die. At first the mom will predigest the meat and then regurgitate it but soon she will bring live prey, so the kits will learn and practice killing. Later the young hunt with their parents.

Each of these four had distinctive personalities. One was aggressive, one playful, one followed the others around, and the fourth was shy and nervous, obviously the runt of the litter.  In the early morning hours, mom would clean her kits, watch over them as they played, nurse them on demand, and produce rabbits and squirrels from a cache to feed her babies as well as herself. She would give them food and show them how to eat, tearing off meat for them and helping them to do it themselves. She kept a careful watch over them while I stayed back, but not hidden, and photographed as they went about their daily lives. The kits will fledge at about seven months. The males will travel away up to 150 miles, while the females usually will stay closer. The adults also disperse, remaining solitary until the next mating season.

The last morning I spent with them, mom approached me and scratched her head on a stick within three feet of me. She came close enough for me to pet, however I resisted, instead enjoying the close up photograph opportunities she gave to me. Later she brought one of her kits up close for a visit as well. Towards the end of the morning, I believe that mom had become so comfortable with me that she left the four kits and headed down the shoreline, presumably to hunt for food.  She seemed convinced that I would not harm her babies and left the babies out with me. The babies played another half hour and then retired to the den for the day.

The adult Red Fox has few enemies other than humans and cars but rabies, mange, and distemper can be a problem. For years unregulated trapping and bounty payments depleted the Red Fox population, but the collapse of the fur industry and the abolishment of most bounty payments have improved the fox numbers. Poultry farmers have made their farms predator-proof, so farmers are killing fewer foxes as well. The Red Fox seems to be spreading its range but competes with the Coyote which may have a restraining effect instead.

To be able to spend a few days with a Red Fox family, photographing their daily lives, was a privilege I will not soon forget.