The leafy sea dragon is a charismatic species native to the
southern coast of Australia. Though these fish resemble seahorses, they are
actually more closely related to the pipefishes, and they may be intermediate
between these two groups of fishes. Leafy sea dragons are named for their
plant-like appearance that allows them to perfectly blend in with algae that
grow in the sea-grass beds and the rocky reefs where they live.
Leafy sea dragons are very poor swimmers and rely on their
camouflage to avoid predation. They are relatively large compared to their
closely related species and reach lengths of up to one foot (30 cm) long. Leafy
sea dragons eat small, plankton crustaceans but are small enough themselves and
have sufficient vision to see and attack individual prey (unlike large filter
feeders). Their heads are relatively large compared to their very small mouths,
so they are able to concentrate enough pressure at their mouths to easily suck
in their prey.
Like in seahorses and pipefishes, male leafy sea dragons
care for the fertilized eggs. They do not have a specialized pouch like male
seahorses but instead carry the eggs under the tail. There, they remain exposed
to the elements but safe, and the male provides them with necessary levels of
oxygen through a specialized, nearby organ. Newly hatched leafy sea dragons
receive no further parental care. They reach sexual maturity in approximately
two years.
The leafy sea dragon is a popular species in public aquaria
and its trade is tightly regulated. There are very few people licensed to
collect leafy sea dragons, and a more significant threat to their populations
comes from their accidental capture in fisheries targeting other species.
Scientists consider this species to be near threatened with extinction. Without
continued careful management of the human activities that affect leafy sea
dragon populations, the species could become more seriously at risk of being
lost.
