AquaRank.com

Abudefduf saxatilis

Common Names: Sergeant Major
Synonyms: Abudefduf ascensionis
Abudefduf marginatus
Glyphidodon moucharra
Glyphidodon saxatilis
Family: Pomacentridae
Category: Damselfish
Distribution: Atlantic - West; Tropical Atlantic. Abundant in the Caribbean, also found in good numbers on West African reefs. Originally considered to be circumtropical until the Indo-Pacific fishes were reclassified as a separate species, Abudefduf vaigiensis.
Main Ecosystem: Reef; Inhabits mature reef systems with abundant growths of stony corals such as Acropora, which are used for shelter.
Temperament: Territorial; The Sergeant Major has a well-deserved reputation for being one of the most territorial of all Damselfishes, and ranks alongside the Genus Dascyllus in this regard. Care is therefore required when choosing aquarium companions, which must be robust enough to withstand periodic displays of aggression from the Sergeant Major, and capable of competing adequately for food. If unwisely added first to an aquarium (as used to be the case when these fishes were used for cycling marine aquaria), there is the real possibility that the fishes will take over the entire aquarium as their exclusive territory and deal with subsequent new additions ruthlessly. This should be borne in mind by anyone contemplating this species on the basis of its documented hardiness.
Diet: Ominvore; The Sergeant Major will eat just about anything edible in the aquarium. Will readily accept a wide variety of aquarium fare, but for optimum health, the meaty foods that it demolishes with undisguised relish should be supplemented with some vegetable matter. The principal problem that the aquarist will face with this fish is not persuading it to eat, but curbing its appetite: it is a gluttonous feeder, and a messy one too. Wild food items recorded as being a mix of filamentous algae and zooplanktonic organisms.
Care: Described in many textbooks as possibly the hardiest of all marine fishes, and with good reason: there are numerous anecdotes testifying to the toughness of this fish, ranging all the way back to when Graham. F. Cox was writing in the 1970s. Capable of surviving water chemistry parameters that would kill other marine fishes in hours, though this is no excuse for careless aquarium maintenance, as the fish relishes pristine water conditions as much as any Butterfly Fish, for example. However, the degree to which the Sergeant Major is a 'bomb proof' marine fish, and its abundance in the wild, has led to it being offered for sale cheaply as a 'first' marine fish. Unfortunately, many naive newcomers to marine fishkeeping have discovered the hard way that the ease of maintenance of this fish comes at the price of its very strongly developed territorial instincts, and consequently experienced aquarists tend to avoid this fish, making disposal of surplus specimens all the more difficult. Because of the aggression issues surrounding this fish, particularly when adult, it should, strictly speaking, be taken on by an aquarist who actually WANTS this species by name, and is prepared to live with the negative attributes as well as the positive. Likely to dig and rearrange the aquascaping to suit itself, particularly if a male and female pair are preparing to spawn.
pH:
Temperature:
24°C - 28°C
75°F - 82°F
Specific Gravity:
1.019 - 1.027
Potential Size: Male: 22.9cm (9")
Female: 22.9cm (9")
Water Region: Middle, Bottom; In the wild, tends to remain close to Acropora or similar coral branches for protection from predators. Juveniles have been observed setting up 'cleaning stations' akin to those of the Cleaner Wrasse, and picking ectoparasites from the surface of larger fishes. Attracted to scuba divers, particularly if it has learned that divers bring food morsels with them in certain tourist spots! In the aquarium, likely to be MUCH bolder and occupy just about any region of the aquarium, particularly when hun
Activity: Diurnal; Active throughout the daytime. In the wild, spends its time foraging for small animals and filamentous algae in between heading for cover from larger, predatory fishes, and seeking a territory for breeding. In the aquarium, likely to spend its waking hours exerting its territorial rights over other fishes, apart from those that are bigger and more aggressive, and during feeding time, will dart about frenziedly after choice morsels. Generally an inquisitive fish, likely to exhibit much curiosity
Gender: No reliable external gender differences visible to the aquarist under normal maintenance conditions. Differences in the shape of the genital papillae of the male and female may be noticed, in accordance with observations for related Damselfishes, when the fishes are preparing to spawn.
Breeding: In the wild, a male sets up a territory and invites females to spawn, which takes place somewhat Cichlid-style after due courtship rituals are observed. Male assumes primary parental care, larval fishes are dispersed into the open sea and spend time as planktonic organisms before settling down to a new home as juvenile fishes. If provided with sufficient space, will spawn in the aquarium. Principal difficulty with breeding this species, as with most marine fishes, centres upon the feeding of the planktonic larval stage of the fry: if this is accomplished successfully, the fry will develop into juvenile fishes are a rapid rate.
Variants: Fishes that were once regarded as being colour or population variants of this fish have since been redesignated as separate species. Basically, if it is a robust bodied, black and white striped Damselfish with a markedly forked tail and yellow body colouration between thevertical bars below the dorsal fin, it is Abudefduf saxatilis: fishes lacking the yellow colour are usually one of the related species.
Comments: Used to be commonly sold in the days when Damselfishes were sold for aquarium cycling (a practice to be strongly discouraged), but its belligerence and relatively muted colour scheme when compared with other Damselfishes has led to a decline in popularity. To illustrate how tough these fishes are, an anecdote from Graham Cox (circa 1970s) is apposite: he disposed of a pair to a Dutch aquarist, who then became tired of their behaviour, and tried disposing of them in a Brine Shrimp rearing tank containing only cooking salt solution. The fishes were still alive nine months later. Marine fishes don't come any more 'bomb proof' than this! A fish for the aquarist who doesn't mind going out on a limb and keeping something regarded by many as 'uncool' - especially if struggling to keep marine fishes on a tight budget and looking for something that will forgive maintenace lapses.
Main Colours: White, Black, Yellow
Markings: Striped Vertical
Mouth: Normal
Tail: Forked
Search: Show similar species
Find compatible species
Image Credit: © FishProfiles.com
Submitted By: Calilasseia
Contributors: Calilasseia
History: View changes to this profile
Edit Profile: