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Hi. My name is Remik and I'm a biologist from the Gdynia Aquarium.

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Today I will tell you a little bit about seahorses.

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I think everyone knows what a seahorse looks like, and the Gdynia Aquarium has it in its logo,

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but what really distinguishes these animals from other creatures

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that we can encounter on the coral reef or in the aquarium?

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Seahorses belong to the Syngnathidae family.

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They live in areas providing a large number of shelters, such as seagrasses, coral reefs, or mangrove forests.

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Depending on the species, they reach from 1.5 to 35 cm in length.

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Their name refers to the chess piece, the knight, whose head resembles a seahorse's head.

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Although they are fish, their body is devoid of scales, and their skin is stretched over bony plates.

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Seahorses swim in a vertical position,

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using their dorsal fin, which can move up to 35 times per second.

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This is a feature that sets them apart from other fish.

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Their pectoral fins, located on both sides of the head behind the eyes,

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are used for steering.

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They also lack a tail fin, as they have a prehensile tail.

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They differ from other fish not only in their body shape but also in their way of life.

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The most unusual differences occur in their mating behavior.

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During copulation, the male receives a packet of eggs from the female,

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which he then places in his brood pouch located on his belly.

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A pair of seahorses can court each other for several days.

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During this time, they can change colors, swim together while holding onto their tails,

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or even hold onto the same blade of grass with their tails.

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Then the ultimate dance begins,

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during which the male, by pumping water through his brood pouch, shows the female that it is empty.

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When the female's eggs mature, she and her partner let go of everything they held onto,

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and then drift upwards with their heads pointed towards each other.

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In the final moment, the lid on the male's brood pouch opens for about 6 seconds,

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during which the female, using an organ called an ovipositor,

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lays anywhere from a few to several thousand eggs into the pouch depending on the species.

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Then they both return to the safe and intricate seafloor.

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The fertilized eggs then settle into the wall of the male's brood pouch

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and are surrounded by sponge-like tissue.

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The pouch acts as an incubator and maintains the eggs in the proper conditions.

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The young hatch inside the pouch, where regulated salinity prepares them for life in the sea.

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Throughout the gestation period, which lasts from two to four weeks for most species,

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the female visits her male every morning.

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When the brood is ready to be born, the male pushes them out of the brood pouch using muscle contractions.

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They usually give birth at night and are ready for another batch of eggs in the morning when their partner returns.

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Seahorses do not take care of their young after birth.

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The fry are susceptible to predators or ocean currents that can wash them away from their feeding grounds

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or into areas where temperature can damage the tiny seahorse bodies.

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Less than 0.5% of young ones survive to adulthood, which explains why litters are so large.

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Although it is not known whether seahorses mate for life,

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it is known that they bond for at least one breeding season.

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As you can expect, keeping seahorses in aquariums is no easy feat.

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Firstly, the water must meet specific parameters.

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Above all, it must be crystal clear.

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Seahorses can't be denied charm and grace, but they certainly won't be Olympic swimmers.

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The water in their tanks can't be strongly agitated,

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as seahorses simply wouldn't be able to overcome such strong wave movements.

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For the same reason, feeding can also be problematic.

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Seahorses are unable to chase their prey throughout the entire tank.

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That's why zooplankton and small crustaceans 

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like copepods, young shrimp, or artemia are used as food.

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Despite this, they have to eat practically all the time due to the lack of a stomach.

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They often anchor themselves in one spot and wait for food to appear in front of their mouths.

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That's why it's important to have plenty of small, non-escaping and accessible food swimming in the aquarium for them.

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Other species swimming in the tank with them can't be too greedy or aggressive either.

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Firstly, because seahorses simply won't be able to defend themselves against their attacks,

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but also because they can starve the seahorses by eating all the available food.

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Keeping adult seahorses is difficult enough, but breeding them is a real art.

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Now that you know how clumsily adult seahorses feed,

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think about the difficulties their 5-millimeter babies have with eating.

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This is one of the most challenging moments in breeding.

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Providing the right amount of food adapted to the small seahorses is crucial.

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This food can be copepods or brine shrimp, but only if they are still very young.

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The artemia larvae that we want to feed the small seahorses cannot be older than 3 hours.

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After this time, they may be too big, and their shells too hard to digest.

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This scheme is additionally complicated by the fact that the artemia hatching time ranges from 18 to 28 hours.

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Depending on their geographic origin.

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This means that we need to estimate the birth time of seahorses

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24 hours before they hatch, with an accuracy of up to 60 minutes.

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One hour late or early, and the young seahorses won't have anything to eat.

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That's why at our aquarium, we feed young seahorses with copepods,

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which do not have a size problem.

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Sometimes, the young seahorses need to be separated from the rest of the tank's inhabitants,

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but they cannot be taken out of the water under any circumstances.

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Even a momentary contact with air can cause the seahorse to inhale a bubble of air,

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which will prevent the young seahorse from diving again.

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As you can see, many elements of breeding success depend on perfect time management,

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often down to the hour and minute.

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But as befits such extraordinary animals, their breeding method is equally extraordinary.