Seahorse

The Latin name of the seahorse “Hippocampus” comes from mythology and is the name of a mythical creature – half-horse, half-fish – on which the sea god Poseidon rode.

Characteristics

What do seahorses look like?

Seahorses are actually fish, even if they don’t look like it at all: Their fins are almost completely reduced, their laterally compressed body is protected by a hard, ribbed skin-bone carapace, and they have a tubular, toothless mouth.

Her German name comes from the shape of her head, which really resembles that of a horse. The curved neck is also similar to that of horses. Their posture is also unusual for a fish: they float upright in the water and do not swim horizontally like the other fish.

Only with the small, almost completely reduced dorsal fin can they slowly move forward, two pectoral fins, which are also strongly reduced, serve as rudders. Their caudal fin also doesn’t look like that of other fish but has been transformed into a prehensile tail that they can use to cling to plants or coral.

Seahorses vary greatly in size. The smallest was discovered only recently: it is the Tasmanian seahorse, which is only 1.5 centimeters long.

The two-centimeter-long pygmy seahorse is also one of the small species. The largest representatives are the pot-bellied seahorse, which measures 25 centimeters, and the Pacific seahorse, which is 20 centimeters long.

The species living in Europe are in the middle: the short-snouted seahorse is seven to 13 centimeters long, and the long-snouted is 8.5 to 18 centimeters. The coloring of the seahorses can be very different: from yellow to orange and purple to brown, black and white. In addition, they can be patterned.

They also have the ability to change their color: if you put different colored animals together, they will adapt in color to each other and to the environment. The long-snouted seahorse even has shaggy appendages on its head and neck that appear like a mane.

Where do seahorses live?

Seahorses live in the warm seas of the world. The short-snouted and long-snouted seahorses are found in the Mediterranean, Black Sea, and eastern Atlantic. It is very rare to find them even in the North Sea. Seahorses thrive in shallow, calm coastal waters. Some species love the dense seagrass meadows, others can also be found on stony, rocky coasts or between algae.

What types of seahorses are there?

There are 30 to 35 different seahorse species. For some, researchers aren’t sure if they’re distinct species, because a species’ seahorses can look different from region to region. The short-snouted and long-snouted seahorses live in the Mediterranean and the Pacific seahorse in the Pacific. Very closely related to seahorses are the small and large sea dragons.

Both species are only found in the cooler waters off the southern coast of Australia. They have various lobe-like appendages so that they resemble a piece of seaweed and are perfectly camouflaged among the algae and in the seagrass beds.

How old do seahorses get?

Seahorses live up to four years in captivity. In nature, they can live for a maximum of six years.

Behave

How do seahorses live?

The strange appearance of seahorses helps them survive: Hardly any predatory fish recognize the strange animals, which often hover between plants, as prey. The hard skin bone shell also spoils the appetite of most fish. Conversely, seahorse prey often notices too late that they are approaching a predator. Seahorses live in pairs and occupy a territory together.

The animals stay together for life, and if one partner dies, the other usually doesn’t survive much longer. Every morning there is a greeting ritual that serves to strengthen the bond between the two partners. The female usually swims to the male and asks him to dance. It grabs the part of the plant with its tail that the male is holding on to, and they both twist around the stem of the plant. Finally, they grab each other’s tails and swim around their territory together. They then separate, and each spends the day independently foraging for food.

Friends and foes of the seahorse

Young seahorses are eaten by predatory fish, especially in the first few weeks of life: probably only one in a thousand young animals survives. Adult animals are so good at camouflage and color matching to their surroundings that they are fairly well protected from predators. However, poisonous sea anemones or corals can be dangerous to them, as can larger hermit crabs.

How do seahorses reproduce?

Raising young seahorses is a man’s job: the males incubate the eggs and take care of the offspring. After a courtship ritual that can last several hours and is similar to the morning greeting ritual, both are ready to mate: The female raises her snout and stretches her tail straight down. The male then prepares his brood pouch. It moves its tail back and forth like a jackknife. This pumps water in and out of the brood pocket so that it is cleaned and contains only fresh, oxygen-rich water. Then the male also stretches his snout upwards.

The female then pulls out a special egg-laying apparatus, inserts it into the male’s brood pouch, and lays around 200 eggs. After this, the pair separates and the male puts his sperm into the brood pouch to inseminate the eggs. The inner wall of the brood pouch is richly stocked with blood vessels that supply the offspring with oxygen and nutrients.

Depending on the temperature, the development of the young takes two to five weeks. Then the “birth” of the young takes place: the male moves his tail again like a jackknife and pumps water into the pouch – the young seahorses are thus thrown out into the open water.

They already look exactly like their parents, but are still tiny and measure only 1.5 centimeters, for example in the long-snouted seahorse. You are independent of the start. They become sexually mature at about six months.

How do seahorses hunt?

Seahorses are typical ambush hunters: they do not hunt but wait motionless and well-hidden between water plants until a prey animal swims in front of their mouths. It is then quickly sucked in with the tubular mouth and swallowed.