Gioca STEMAnimals

Animals · Seas and oceans

Seahorse

Hippocampus hippocampus

The male carries the whole pregnancy

A seahorse anchored upright by its prehensile tail to plant debris on the sandy sea floor.
A seahorse anchored upright by its prehensile tail to plant debris on the sandy sea floor.
  • Status: Unknown
  • Coastal sandy seabeds of the Mediterranean and eastern Atlantic

Numbers

Weight
0,1 ozfrom 0.1 to 0.2 oz
Length
4 inusually between 3.5 and 4.5 inches, rarely up to 6
Lifespan
3 years1 to 5 years depending on the species
Male gestation
2 monthseggs remain in the male brood pouch
Depth
200 ftexceptional case, usually stays between 3 and 30 feet
Tail bone rings
36 ringsfrom 34 to 36, plus 11 to 12 in the belly region

Ten fun facts

  1. the male carries the eggs in a brood pouch on his belly, incubating them for about two months.

  2. the young emerge from an opening at the top of the pouch looking like adults and live in plankton for eight weeks.

  3. it has no scales, because its body is protected by bony plates fused into rings like a small suit of armor.

  4. the tail fin is completely missing because the tail has turned into a prehensile organ used for holding onto objects.

  5. the head forms a ninety degree angle or more with the body, which is a rare feature among fish species.

  6. the crown on its neck bears a small horn like spine above each eye, which is absent in related species.

  7. its color ranges from dark brown to light yellow, so color alone cannot reliably identify this particular species.

  8. it is euryhaline, meaning it tolerates brackish waters and enters lagoons where the salt levels change constantly.

  9. international trade in all seahorse species is strictly regulated and requires official CITES documentation and permits.

  10. in certain areas of Portugal populations collapsed because seahorses were caught by accident in shore pulled trawling nets.

The quiz answers

Five questions about this animal. Pick an answer and find out if it is the right one.

Question 1 of 5

Who carries out the pregnancy in seahorses?

Question 2 of 5

What covers the body of this fish?

Question 3 of 5

Which fin is completely missing?

Question 4 of 5

At what depth is it usually found?

Question 5 of 5

How does the IUCN classify this species?

Try it yourself

Experiment 1

Mark two months from today on a calendar. That is the exact amount of time the male seahorse carries eggs in his belly pouch.

Experiment 2

Measure four inches on a ruler and hold it vertically. That is the typical full size of an adult seahorse, including its tail.

Experiment 3

Bend a piece of wire into a ninety degree angle. That shows the sharp bend where the head meets the body in this fish.

Data from Wikidata (Q302969) and Wikipedia (Short-snouted seahorse).