The beautiful colored seahorses belong to the most magnificent and most remarkable organisms of the seas. Actually a seahorse is quite normal deep sea fish, coming along only in a very special dress. There are about 35 different species of seahorses spread all over the world, but only a small spectrum of this variety is frequently imported for aquarist purposes.
Seahorses - Classification
Seahorsesare vertebrate fish. Technically, their taxanomic classification is the Kingdom Animalia, Phylum Chordata, Sub-phylum Vertebrata, Class Osteichthyes and Order Perciformes. They belong to the family Syngnathidae (syn - together or with [Greek] and gnathos - jaw [Greek]) that includes sea dragons, pipefishes and pipehorses. Seahorses make up the genus Hippocampus (hippo - horse [Greek] and campos - sea animal [Greek]).
Seahorses - Physical Characteristics
They all range in size from 6-12 inches although most fall in the 6-inch category. The color range of sea horses is enormous. They can be white, yellow, red, brown, black, gray, spotted or banded. Sea horses are pieced together with many different parts and abilities of other sea animals. They have the head of a horse with the snout of an aardvark, spines like a puffer fish, a pouch of a kangaroo, eyes like a lizards, the tail of a monkey, an armor plated body like Stegosaurus, the ability to change colors like a chameleon and to wrap their tails around things.
The tube-shaped snout lent to the sea horse by the aardvark is its mouth. It is made of an upper and lower jaw, both of which are toothless! The seahorse opens and closes its jaw in a rapid snapping movement while lowering the floor of its mouth to increase volume. The snout is designed to suck up microscopic animals that live in the water. These animals include small crustaceans, brine shrimp, zooplankton, worms and other invertebrates. Seahorses usually ambush these microscopic animals as they swim past. The bony plate of armor that Stegosaurus loaned the seahorse covers its entire body. This suit of armor consists of many bony plates that interlock throughout the seahorses’ body that are arranged into "rings". Each species has a distinct number of rings but that number varies between different members of the Hippocampus family. The spines of the puffer fish mark the joints where the armor interlocks. These two features provide the seahorse with protection from predators but also limit their flexibility. The prehensile monkeys tail also provides a very important function in the every day life of a sea horse. Anybody who has ever been in the ocean knows that there is a strong undercurrent or under toe that can be very overwhelming. So they are not swept away by this current, sea horses wrap their tales around coral, sea grass or any other convenient object on the ocean floor.
Because sea horses wear such heavy armor, they are very poor swimmers. They spend most of the day resting by anchoring themselves with their tail. They have no caudal or tailfin like all other fishes does. When they do swim, they majestically glide through the water without any visible effort. This is because they have a transparent fin on their back, called a dorsal fin that beats 20-30 times per second, so fast we can't see it! The dorsal fin moves the seahorse forward. The pectoral fin controls which way the seahorse is going to turn. When they do swim, it is in an up and down fashion. They regulate whether then swim up or down by controlling the volume of gas in their bodies.
The center of the body of the seahorse has three pairs of lateral ridges with one ridge along the stomach area. Its long, tubular mouth opening has no teeth and although there is no fore covering over the gills, this sea fish does have small round gill openings.
Seahorses - Ecology and range
Seahorses inhabit coral reefs and sea grass beds. Some inhabit brackish or freshwater habitat. They prefer sheltered areas and are well camouflaged. They are found all over the world. Seahorses are usually spotted in tropical, subtropical and temperate ocean waters although some species have been found that have penetrated into the northern regions. The seahorse is most often found in algae colonies or coastal seaweed since the species tends to prefer shallow waters that have a muddy floor rich in plant growth or near reefs.
Seahorses - Behavior
Seahorses swim upright with their tails down and their heads up. They feed on small crustaceans employing a sit and wait strategy, remaining stationary and snapping prey that comes near. With their tube like mouth they create a vacuum that draws their prey into the mouth.
Each one of the special features plays an important role in the life of a sea horse. The seahorse has the eyes of a lizard, which mean one eye looks left while the other eye looks right. Both eyes do not look ahead like our eyes do. This unique ability allows the seahorse to look for enemies with one eye while searching for food with the other eye. It is also believed that with this binocular vision seahorses have, they can see their microscopic prey.
The sea horse relies on its ability to camouflage itself for protection against predators like large fish, birds, crabs and sea turtles. With its camouflaging ability, it can change colors in the blink of an eye. Seahorses are capable of rapid color transformations to blend with their surroundings. While mating they change colors either lightening or darkening their skin. Seahorses are monogamous and during the mating period they engage in a lengthy courtship. The male seahorse carries the eggs in a brood pouch where they are fertilized and incubated until they hatch.
Seahorses sit for hours in front of or beneath live rocks and stick their snout into each hole and crack. They pursue booty only rarely but wait patiently for the fodder coming along. Besides they get on other seahorses nerves by permanently hanging on them and only hardly been shaken off. Seahorses get rid of their excrements in an elegant way by doing a 360° turn around the horizontal axis like a dancer.
Seahorses - Food
Seahorses eat by a quite special snatch-sucking movement of their snout. This suction movement is so strong that a clearly audible noise develops and even for fodder, which exceeds the snout diameter by far (for example large ghost shrimp), is easily torn and in-sucked.
Immediately after aspirating the booty food remainders withdraw in form of a breath-fine nebula cloud from the sides of the seahorses head, it seems as if its head steams. Before a seahorse catches its food however, time goes by. The seahorse watches its potential booty quite exactly. Already a few days old babies look exactly at each piece of plankton or brine shrimp before the suck it. But if the animals made however only once their choice and the booty tries to escape, the otherwise so leisurely coming along seahorses transform suddenly into fast and agile floats chasing the potential food until they catch it.
Seahorse and other pipefish are known to feed on water fleas, small crustaceans, cyclopids, small fishes and other organisms. A large amount of food is required for this tiny creature whose eyes move independently and protrude so they can easily watch their prey without moving their body or head. When their prey is close the seahorse will slowly bring their snout near the prey before quickly sucking in the prey with a crackling sound. The sound and suction are created when the hybrid arch is retracted and the lower mouth drops down to enlarge the mouth cavity.
Seahorses - Courting and Reproduction
Keeping male and female seahorses in a tank they will soon start courting. In the morning and in the evening the couple does a round through the tank holding each other with the end of their tales. Their bodies are in form of a "V" as they swim through the tank, remaining for a while at different waypoints in order to examine their neighborhood in every detail.
While these behavior rituals seem to be of absolute priority for the male seahorses, female seahorses are substantially fewer concentrated and let themselves be easily diverted by other attractions (especially food). In such cases occasionally a kind of punishment of the female takes place, as the male snatches at the head of the female for disciplining, which probably might be rather painful. The same aggressive reaction is to be determined, if the female seahorse approaches another male.
With the fidelity seahorses in tanks do not take it as strict as seahorses in nature, where the partnership lasts as long as their life. Keeping one male and several females in a tank, the male changes its partner again and again (in extreme cases almost daily). If there are several couples in a tank, one can observe stable linkages over a long time. After the death of the partner the surviving seahorse usually chooses a new partner, but sometimes it also dies within a few days. If no suitable partner of the same type is available, the seahorse looks around for a seahorse of another species.
Seahorses mate during the full moon. They normally go through a series of courtship rituals that lasts several days before they mate. The courtship ritual involves such things as color changes and synchronized swimming. The female makes between 200 - 600 eggs, which are a pinkish color. The size of the eggs varies from .5 to 1.5 millimeters, depending on the species. The female then deposits them in the males’ brood pouch where he fertilizes them and lets them grow. The developing embryos are oxygenated and maintained for 3 - 6 weeks. When the male gives birth, he may actually experience birth pain. When they hatch, the baby sea ponies are about 1 centimeter long. When the baby seahorses are born, they must fend for themselves because the male will not care for them.
Seahorses - Mating
Before the actual mating the male seahorse offers its waterfilled-breeding bag over hours to the female again and again. It opens the input of the pouch extremely wide by a special movement. The female seahorse "docks" with the mid part of its body to the opening of the males pouch and fills in orange colored eggs. Subsequently the male seahorse then sways the body in order to distribute the eggs in the pouch.
In seahorses pregnancy happens to the male animals. Within two or three weeks between 50 and 1.500 seahorse babies develop inside the males pouch, which are finally living born.
Frequently not all of the babies will dismiss at one time from the pouch, but in several phases over some minutes or hours, in extreme cases it takes even one or two days. Several males die a few days after birth of the ponies because of remaining dead babies in the pouch resulting in putrefaction and bacterial infection.
Many pregnancies can occur consecutively, whereby the duration of pregnancy is 2 to 5 weeks with an average of 2 to 3 weeks. In addition, it seems that there are months-long infertile periods. There are also "false pregnancies", the males pouch seems to be filled to the maximum for a few days and suddenly is of normal constitution again. Mating does not only occur between seahorses of the same species, but also between different species.
Seahorses - The young infant
Seahorse babies in the moment of birth are only a few millimeters in size, but they already look like real seahorses. Instantly they curiously explore their new habitat. If you do not catch the small animals out of the tank, you usually won’t see anything of them the following day. The size of the newborn seahorses varies significantly, whereby particularly small fry has almost no chance of survival.
The new generation grows up really slow during the first weeks of their life. Four months later the largest of my seahorses were about 2.5 inch long (H. reidi), whereby there were enormous growth differences. These differences seem to be in direct relationship with the individual skill of catching food. After 5 months their size is approximately 3 inch (tank conditions), after 8 months approx. 5 inch. The size of adult H. reidi is about 6 to 8 inch.
The maximum life expectancy of seahorses in nature is up to four years (depending on species), whereby sexual maturity already occurs at the age of 6 months. Nearly all of my own H. reidi died of old age. I purchased these seahorses fully-grown in adult age (1 year or older). In my tanks they lived for another 2 years and more. The oldest of my self-bred seahorses is now 21 months old.
Seahorses - Friendliness
Seahorses can become very friendly. Some of them eat out of the keepers hand and grab his fingers as he is doing some work in the tank. The affinity of seahorses to objects not available in nature is interesting: They for example really love a normal thermometer in my tank giving them a perfect hold for their tail.
Seahorses - Motion
Using their tails they will snag seaweed hanging on while they drift along in the ocean. This method enables the tiny seahorse to cover vast distances across the ocean floor as they search for food.
Seahorses and other pipefish are able to move through the water using the distinctive motions of their dorsal and anal fins. Typically with bony fish a swimming motion is used that occurs with the undulation of the body but this rarely occurs with the seahorse. In most cases this body unification is only when they are forced to flee quickly from a predator. Even though the seahorses is generally holding on to plant forms they can also swim up and down in vertically and even in spiral motions. Their greatest speeds are produced when they are lying on their back swimming horizontally while extending their tail to maintain their equilibrium.
Seahorses - Economical and Biological Uses
The trade of seahorses is legal. But if we are not careful, then we could push this amazing creature into extinction. The Chinese, Indonesians and Central Filipinos use sea horses in their medicines as cures for illnesses, as aphrodisiacs and as food. Medicinal purposes for seahorses include using them as "cures" for asthma, arteriosclerosis, incontinence and impotence, thyroid disorders, skin ailments, broken bones and heart disease. Some areas even use seahorses as an aid in childbirth. The price of dried seahorses can fetch up to US $550 a pound! The use of sea horses in aquariums, especially in North America, is also steadily growing but many populations are now coming from seahorse farms. Their inshore habitats are also being destroyed which in turn destroys them. Water pollution is also aiding in the destruction of these wondrous creatures.
Seahorses are being over collected. Please help preservation efforts and don't use them in aquariums. Reports indicate for example, that the Hippocampus population in the central Philippines have diminished by 70% between 1985 and 1995! Thousands of seahorses are imported to Europe, the United States and Japan as pets for aquariums.
Dried seahorses are often offered as souvenirs. However the biggest consumer is traditional Chinese, Japanese and Korean medicine. Dried seahorses are used to "cure" a wide range of illnesses such as asthma, arteriosclerosis skin diseases but most important sexual dysfunction. The annual consumption by Asians nations of dried seahorses has been estimated at 45 tons (= ca. 16 mill. individuals!).
Seahorses - For Aquariums
Seahorse keeping should not be tackled by the casual aquarist, because seahorses usually die quickly in captivity. Seahorses are already at risk around the world, partly because they are exploited for aquarium fishes.
Seahorses are in the same family as pipefishes and seadragons (Syngnathidae). There are probably about 35 seahorse species in the world, all in the genus Hippocampus, ranging in adult size from the 40 cm Eastern Pacific seahorse (H. ingens) to the 1.5 cm New Caledonia seahorse (H. bargibanti). Seahorses usually cling to vegetation or other holdfasts such as sponges, pilings or ropes on the bottom, sometimes in less than one meter of water and often only meters from shores. Crabs occasionally prey on seahorses. Seahorses can change colors often and easily. Do not distinguish between seahorses by color. The head coronet shape and size vary greatly from seahorse to seahorse and are an excellent way of identifying seahorses individually.
Seahorses - Choosing your sea-horses
Choose your seahorses with great care. If they have grey tinges or signs of fungus or sloughing skin, do not buy them. It is difficult to impossible to treat most seahorse illnesses. Seahorses in good condition have rounded bodies. If the body is sunken and concave it is probably best not to buy the animal, as it has obviously not been properly cared for and will almost certainly succumb to illness. Seahorses are very vulnerable to bacterial infections so place new seahorses in a separate tank which has been treated with a wide-spectrum antibiotic or dip them in a bath. To acclimate seahorses, the unopened plastic bag should be placed in the aquarium for about half an hour to allow water temperatures to equalize. Then gradually, over the next hour, add aquarium water to the bag. Once the bag is more than half full of aquarium water, you can risk adding the seahorse to the tank.
To encourage a seahorse to release a holdfast, move the holdfast gently. If that fails, then tickle its tail. As a last resort, try to uncurl the tall gently from the perch. Never use force to get a seahorse to release a holdfast. You will do great damage to its tail. Just wait and try again.
Seahorses - Choosing your aqarium for sea-horses
Seahorses are oriented vertically and are not suited to shallow aquaria (45 cm). They are unlikely to mate in shallow water because they rise as they copulate. However, they often move across the tank bottom so give them as much space as possible. You should not keep many seahorses together. They do not live in groups in the wild and they are very prone to communicable diseases and ailments. Prefereable there should not be more than four seahorses in a 100 liter aquarium and not keeping any seahorses in much smaller tanks. An ultraviolet sterilizer is an important because seahorses are very vulnerable to bacterial infections. It's a good idea to hide airstones. Seahorses are subject to many buoyancy problems that may result from or be exaggerated by sitting in airstone bubbles. Water quality is all-important for maintaining seahorse health.
Seahorses - Aquarium Settings
Seahorses require many holdfasts, as they become stressed if they cannot hold onto something with their tails. The best holdfasts are natural surfaces such as "living rocks." Excellent substitutes are soft plastic plants. They should be quite tall and have many branching parts. It is also important to provide a reasonably complex environment so the seahorses can escape into hidden corners. They become stressed it they are too exposed. It's also a good idea to have a tank backing to give them a reference point and to help them orientate.
Seahorses - Companions in the watertank
It's very important not to put seahorses in an aquarium with fast, agile fishes or with aggressive feeders. They tend to do best in invertebrate aquaria but otherwise they can be kept with dragonettes (Callionymus bairdi), tiny trunk fishes (Lactophrys trigonus), small pipefishes (although it has been suggested that these may become 'fin pickers'; as they grow), blennies, etc. Never place seahorses with active feeders such as damselfish, puffers, butterfly Sea Fish or angelfish. Blennies in particular make quite good companions because they help to keep the tank clean.
Seahorses - Lighting in your watertank
Seahorses interact most in the hours just after dawn. I suggest, therefore, that you keep seahorses on 3 hours half-light/10 hours light/3 hours half-light/8 hours dark. The half-light can be produced by a lamp some distance from the aquarium.
Seahorses - Feeding your sea-horses
Seahorses eat a great deal but are rather particular. Feeding seahorses is one of the most difficult aspects of keeping them in captivity. Seahorses usually eat only live, fresh food. They need food variety and cannot be fed solely on Artemia as these alone provide a highly unbalanced diet. With patience and effort, you may convince seahorses to eat some frozen foods and these can be a good backup when fresh food fails. However, you must not rely solely on frozen foods as these alone will eventually result in malnutrition and illness.
Seahorses - Healthcare
Seahorse are vulnerable to many fungal, bacterial and parasitic ailments and infestations and few seahorses ever recover from a serious illness. Seahorses should be inspected every day for changes in their health and any ailment treated immediately; one seahorse's illness usually hits all seahorses in the tank very quickly. Any ill seahorse should be isolated at once. If in doubt, I risk treating them with a wide-spectrum antibiotic.
Buoyancy problems are fairly specific to seahorses. Any seahorse staying constantly near the surface is almost certainly an ill seahorse. You should react at once as buoyancy problems are serious and often fatal. Again, prevention is better than cure. Try to ensure that you have no dissolved gases in your system (in contrast to suspended gases) as these appear to be a major trouble source. Symptoms are the following:
The number(s) in brackets refers to possible causes and solutions below.
- A grossly distended body - by then, the problem is far advanced (3)
- Inflated pouch not due to pregnancy - avoid wishful thinking if the animal hasn't been near a female (1)
- A constant head down position when swimming (1,2,3)
- The tail curled well back and up behind the trunk (2)
- Small bumps on body surface (2)
- Tightly curled position (when trying to descend), held for an unusually long period with little progress (1,2,3)
- Immediately bobbing to surface after release from holdfast (1,3)
- Lying approximately horizontally at water surface, even if the tail is holding something (1,3)
The following are problems common to many fishes and can be pronounced in seahorses:
Bacterial ailments result in greying body parts with ensuring skin sloughing and secondary ailments. Treatment does not seem to be effective and most animals die within days. A dip may help seahorses combat such illnesses. I have found that if bacterial infections do take hold, they are distressing and incurable. An ultraviolet sterilizer can be enormously helpful in combating bacterial infections.
- Air trapped in the pouch (males). You can try the following to release the air. Do not lift the animal out of the water. Keep the seahorse underwater and massage the pouch gently. Hold the head upwards so the air can escape. Stretch the pouch between your thumb and forefinger. Manipulate gently and insert a hollow, blunt small-bore object (e.g. plastic tubing). Exert gentle pressure on the pouch. The gas may escape via the tube. Move the tube gently around if needed. You may need to suck on tube as you massage pouch (yuck!). Ensure that you get the air out. Then monitor that animal as buoyancy problems tend to reoccur in the same animals. This problem is especially prevalent around courtship periods and occurs if males dilate the pouch opening in air streams.
- Air trapped under the skin is a more acute problem. Use a sterile syringe needle (with a tiny diameter). Slip it gently (at an angle) under the skin to pierce a small hole. Remove the needle and then massage the bubbles out while the animal is under water. Pierce all the bubbles you see because they are usually interconnected and missing once causes a repeat performance. Keep the Sea Animal in a very clean tank after puncturing the skin.
- Air trapped internally is very serious and generally results in death. I am unable to suggest anything useful to do in this case. Try to detect this condition early on as it only worsens. Seahorses appear to have no solutions of their own and become very stressed by such buoyancy problems. Seahorses in this condition have massively bloated bodies and get several related problems such as sores, skin cracks, frayed and tattered tails, bony plate separation and internal injuries.
Fungal infections are quite common. If any area develops a white "fuzzy" look and begins to look soft and spongy, treat for fungus. ISOLATE. See aquarium manuals for precise instructions. One possible method is to add malachite green to a treatment tank. Be warned, though, that seahorses can suffer ill effects from too much malachite green so remove the seahorse after a few days or change much of the water. Otherwise, you can dip the seahorse in more concentrated malachite green, or try swabbing the affected part with 1% malachite green. Be certain that you are using zinc free malachite green. Wear gloves because this stuff stains.
Parasites on seahorses are usually a Glugea microsporidian but other parasites may also afflict them. Most parasites appear initially as small, white dots on the seahorse and can be confused with the natural markings on the seahorse. Know your seahorses' markings well and check them regularly. Sometimes, if things have gone too far, the parasites clump into "cauliflower" or "wart" groups. One possible treatment is to place seahorses in a freshwater bath and then dip them in a formalin bath. You can also treat with copper sulphate. Follow instructions in a good manual. Seahorses surprisingly, need not be considered very delicate when treating their ailments and can be subjected to reasonably strong cures...
Wounds are not common in seahorses as they are very passive Deep Sea Fishes. If something does happen, try to leave the wound alone. Many things solve themselves if left alone in a clean tank. Otherwise treat according to a good manual. Dilute iodine on seahorse wounds appears to cause more trouble than it solves.
Protozoan or crustacean infections happen in seahorses. If a seahorse is gasping, panting, or lethargic, it may be a protozoan infections or crustacean infestation in the gills. This can be treated by dipping in a freshwater bath and then in a formalin bath. You should see little white things fleeing from the respiratory spiracles/pores etc. on top of the head.
Finally, please be realistic about your chances of curing an ill seahorse. If a seahorse is deteriorating rapidly or suffering evidently, please do not insist that the animal dies slowly, and perhaps painfully. It is far better to make the decision and kill the animal quickly. If you can't do that, you should not be keeping seahorses.
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