While it varies by species, most seahorses are sexually mature at
approximately 6 months of age but usually their first mating is at 7-8
months. It has generally been believed that some species of seahorses are
monogamous and even that they mate for life. This belief is
currently being debated and it now seems that many mate for a breeding
season. Inter-breeding among some species does
happen, however, little information is available about the
offspring of such matings. The quality and variety of the
nutrition of the adults before the pregnancy is believed to have a
significant effect on the health and survivability of the fry.
The courtship dance of seahorses is beautiful. They lighten their
colors, duck their heads, twine tails and swim around the tank together.
The male often displays his pouch, even flushing it with water to show
the female that he is ready to receive the eggs. The dancing
continues for several days until the eggs are ready. The transfer
of eggs is done during the dance as the seahorses rise in the water
column. The female uses her ovipositor to place the eggs in the
pouch of the male where they are fertilized.
Occasionally, the small round eggs are seen on the
bottom of the tank either when there is no male available to receive
them or when the transfer is not made correctly.
During the pregnancy, the male will probably be less active and a
bit anti-social. He may
also tend to ignore food so it may be necessary to provide special treats to encourage him to eat.
Birth of premature fry is not unusual particularly in the first broods
the male carries.
Gestation varies by species but is generally from 14 to 28 days.
You should carefully cover all intakes, pumps, and filters with sponge
or netting before the expected birthing to prevent the newborn fry from
being trapped or injured. Fry are surprisingly able to find any
possible danger. If you cannot "fry-proof" the tank, or if you
have tank mates that may eat the fry, you may want to move the father to
another tank prior to the birth. You will definitely want to
remove the fry to a nursery after the
birth. We use a brine shrimp net to more the fry. Some
breeders believe it may be harmful to expose them to air and they use a very small cup or
container (a 35mm film canister works) to capture them, or suck them up
gently with a turkey baster which we also use. It is very unlikely that adult
seahorses will eat the fry, but it is possible.
Birth usually is in the early morning hours and often a few fry will be
released a day or two before the main event. The male uses a
jackknife action to push out the fry which are fully formed miniatures
of adults and vary in size by species. You will find more
information on our fry raising pages.
Depending on the species, a brood may number up to 1500 fry, a young
seahorse may have as few as 5.