Growing Up … on the Reef

A couple of months ago, I acquired a baby Moyer’s Dragonet (Synchiropus moyeri) – a fish that many aquarium enthusiasts know as one of the species of dragonet that shares the general trade name “scooter blenny.”

We named him “Tai,” a word which means “fat” in Japanese and “supreme” in Mandarin Chinese – both of which are starting to fit him well.

The Moyer’s dragonet differs from other species within its genus mostly in terms of color: the Moyer’s has yellow fins with black or green highlights and a more brilliant adult coloration than its cousin, the Red Starry Dragonet (Synchiropus stellatus).

Dragonets “scoot” along the reef, and rarely swim in open water. Although they can swim, their small pectoral fins are low on the body and better suited to helping them swim in little “hops” along the reef as they search for food.

In the wild, dragonets eat tiny, live marine crustaceans and copepods, including gammarus and other small aquatic species. My captive dragonets all eat frozen mysis (in addition to foraging for the little copepods that live in my reef), which is fortunate because a dragonet can quickly denude a system of ‘pods and other viable live food sources if they don’t learn to eat “dead foods” as well.

Male dragonets have a large, decorative dorsal fin that they raise to signal their territory or to attract a mate. For the first few weeks, little Tai was far too timid (or possibly too young) to raise his fin “in public” – if he did it at all, we never saw him. Then, about a week ago, I noticed him experimenting with fin flares. At first, he did it only in the corners of the tank, and when he was certain none of the other fish were watching. As a newcomer to the tank, he apparently didn’t want to send an inadvertent challenge that a more dominant fish might feel compelled to answer.

Recently, he’s gotten a bit more daring, though his flares are short (about one second in length) and he flees to the rocks when he sees me trying to capture the moment. However, over the weekend I did manage to catch one (slightly out of focus) shot of Tai mid-flare, which shows the unusual size and lovely patterning on his fin. 

The size and elaborate colors on a dragonet’s fin have an impact on mating and territorial dominance; not surprisingly, dominance goes to the males with larger, more beautiful fins. Although he won’t have to compete for the only female in my reef, little Tai wouldn’t have to worry–he’s got plenty of fin for the job of dominant male.

Have you ever seen a scooter blenny, in the wild or in a reef aquarium? What do you think of the giant sail fins?