Lawnmower Blenny

The Lawnmower Blenny (also known as the Jeweled Rockskipper, algae blenny, or banded blenny) is a saltwater fish, widely distributed throughout the Indo-Pacific, from East Africa and the Red Sea to Micronesia and northern Australia.

It is not sought after as a commercial fish for food, but it is a popular addition to many fish tanks because of the changing color of its body.

3 Lawnmower Blenny Facts

• The color of the Lawnmower Blenny changes with its environment and mood.
• It primarily inhabits shallow saltwater environments, such as reef flats and lagoons, where it grazes on algae and sometimes consumes detritus or small invertebrates.
• They only breed in the late spring and early summer months due to the change in warmth.

Classification and Scientific Name

Originally discovered in 1786, the lawnmower blenny’s scientific name is Salarias fasciatus. While “Salarias” comes from the Latin word for trout, “fasciatus” means “banded.” They have many common names they go by, including the Jeweled Rockskipper, algae blenny, banded blenny, banded-jeweled blenny, barred blenny, lineated blenny, lined blenny, painted blenny, and sailfin blenny.
The lawnmower blenny is in the order Blenniiformes, which includes 151 genera and almost 900 different species. The order includes many types of fish, though only six families are actually classified as “true” blennies. The family is Blenniidae.

Appearance

Part of the reason that the Lawnmower Blenny finds itself on the minds of pet owners is due to the changing color of its body. At no more than 3.7 to 4.2 inches in length, the color of the entire body can change to blend in with its surroundings, protecting it from predators. The intensity of these changing colors changes with their mood as well. To break up the color, it also features white spots along the body and darker lines towards the front. While the rest of the body can change, some individuals may display blue spots or markings, but these are not always present or consistent.

With no notch in the dorsal fin, these fish have smooth lips with tentacle-like cirri along their body. They have a rather fat belly, making them look almost comedic.

Distribution, Population, and Habitat

Where to Find Lawnmower Blennies and How to Catch Them

The easiest place to find the saltwater blenny in its natural habitat is in Australasia, ranging from East Africa to the Islands of Micronesia. It prefers to live along shallow reef flats, allowing it to consistently graze on the algae on them. Their preferred water type is saltwater.

Although their actual population is unknown, they are considered Least Concern, and no conservation efforts are currently being made. Since they are often kept as pets, they don’t need to be sourced from the wild to care for. Instead, breeders will sell them directly to pet stores. If you need to catch one of these fish in the tank to clean, using a net is all you’ll need.

Predators and Prey

Unfortunately for the Lawnmower Blenny, this fish is primarily prey for other animals. Though they are technically considered to be herbivores, they are more accurately referred to as detritivores, which means their diet consists of dead organic material. Their main food is algae.

What eats Lawnmower Blennies?

The Lawnmower Blenny is often consumed by fish larger than it is, such as larger predatory reef fish found in the Indo-Pacific, including groupers and snappers. To protect itself from predators, it uses the changing color of its body to hide. It sometimes hides in oyster reefs, but it is a natural part of the bottom of the food chain.

What does the Lawnmower Blenny eat?

While Lawnmower Blenny doesn’t really have any prey that it goes after, it can become aggressive with other fish in its tank as it gets older. This aggression isn’t really noted in the wild because it has plenty of space to roam.

Reproduction and Lifespan

Typically, the Lawnmower Blenny spawns in the late spring and early summer between April and June. The mating is set off by the increased temperature, which pet owners can replicate in their tank with enough dedication. If this environment is changed, it is possible to breed them at home with highly specific care, but it can be difficult for a novice. The tank must be raised to 78 degrees Fahrenheit, and breeding often has to be moved to another tank.

In the wild, however, they lay eggs in empty shells, allowing males to fertilize them. Once on the substrate of these shells, they will stay there until they hatch. The resulting young larvae will stay in shallow water and feed on plankton.

Fishing And Cooking

The Lawnmower Blenny is a rather small fish, so it is not ordinarily fished as a delicacy. There’s no commercial demand for these fish to eat, but they are popular in the pet trade.