The so-called Humbug
Damsels of the genus Dascyllus are perennial favorites
of beginning marine aquarists, and for good reason. They are
tough little characters, readily available, inexpensive, attractive
and able to withstand the unforgiving period of time most
beginners spend on the marine aquarium learning curve. Sounds
like the perfect fish, doesn't it? I have not yet mentioned
their temperament. They happen to be exceptionally territorial,
highly aggressive and totally fearless. These attributes make
more experienced hobbyists avoid them. Even so, three species
in this genus regularly make the top ten list of most frequently
imported marine fishes.
Classification:
Damsels, along with
their relatives, the clownfishes, make up the family Pomacentridae.
This family consists of 28 genera and 321 species (Fenner,
2001). The subfamily Chrominae consists of the genera Acanthochromis,
Azurina, Chromis, and Dascyllus (Schultz,
2003). The first two genera are not generally kept in aquaria,
but the other two are staple organisms in the marine ornamental
trade. Note that these groupings are made on the basis of
shared structural characteristics, not temperament. As anyone
that has ever kept Chromis and Dascyllus can
surely tell you, they do not behave the same. The genus Dascyllus
has nine species, three of which are routinely offered for
sale, another two that are available frequently, three available
only occasionally, and one species I have yet to see ever
offered for sale.
Pomacentridae
- Chrominae
- Dascyllus
- albisella
- aruanus
- carneus
- flavicaudus
- marginatus
- melanurus
- reticulatus
- strasburgi
- trimaculatus
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Dascyllus
albisella:
The so-called Hawaiian humbug, besides being a native to Hawaiian
waters, is also found at Johnston Islands, where it has been
found living among branching corals (Pocillopora species)
as well as some anemones (Marcanthia cookei). These
fish are occasionally available and grow to a substantial
length of five inches.
Dascyllus
aruanus:
This is the extremely common Three-Stripe or White-Tail damsel
(photo right). They are found throughout the Indo-Pacific
region and are available in most any local fish store on any
given day. They grow to almost four inches and are usually
found living in and among Acropora stands in the wild.
Dascyllus
carneus:
This species is only occasionally offered for sale, usually
by the name Cloudy or Blue-Spot Dascyllus. They are
found throughout the Indian Ocean where they associate with
various branching corals. They are relatively small with a
maximum length of less than three inches.
Dascyllus
flavicaudus:
The Yellow-Tail humbug is another irregular offering from
the Eastern Central Pacific; for instance, the Cook Islands.
They are one of the larger species, growing to not quite five
inches.
Dascyllus
marginatus:
This species is called the Red Sea or Marginate damsel and,
as the name implies, they come from the Red Sea as well as
the Gulf of Oman, where they grow to barely over two inches
long as adults and hide among Stylophora, Acropora
and Porites corals.
Dascyllus marginatus. Photo courtesy of Roberto
Sozzani of ScubaBob.
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Dascyllus
melanurus:
The Four-Stripe or Black-Tail humbug is another species that
can be found on any given day at a majority of fish stores
and wholesale facilities. Their range includes all of the
Western Indo-Pacific and they grow to about three inches.
They are usually found near Acropora species.
Dascyllus melanurus. Photos courtesy of Malibu
Tony (aka: 37 FLATHEAD).
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Dascyllus
reticulatus:
The Reticulate humbug (below) is sometimes called the Two-Stripe
humbug, although its second stripe is not always very sharp
at all. The first stripe is evident just behind the gill plate
while the second "stripe" is best described as a
darkened area at the base of the tail. They are found throughout
the Eastern Indian Ocean and Western Pacific, usually in association
with branching corals such as Pocillopora eydouxi.
Dascyllus reticulatus, seen here in a home aquarium.
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Dascyllus
strasburgi:
I have never yet seen this species for sale. They are native
to the Marquesas Islands where they can be found associated
with Cryptodendron species anemones. They are a medium-sized
Dascyllus, typically reaching three and a half inches
in length.
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Photo courtesy of Greg Rothschild. |
Dascyllus
trimaculatus:
This species is the other extraordinarily common humbug species,
the Domino or Three-Spot damsel (photo right). They are also
the largest of the Dascyllus species, even though the
FishBase
website lists them as reaching only a little over four inches
in length. I have seen them myself easily approaching a bruising
six inches long! That makes this deep-bodied fish about as
large as a coffee saucer and rather intimidating when full
grown. They are found inhabiting both anemones and coral heads,
as well as the occasional biker bar looking to pick a fight.
Their coloration can vary by geographic location, ranging
from the common all black with three white spots to black
with white spots and a yellow belly to an almost all black
variety, although these color variations do not denote separate
species.
An unusual color morph of Dascyllus trimaculatus.
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Selection:
Finding a healthy
specimen in this genus is usually quite easy. I generally
avoid any newly arrived acquisition, preferring to wait until
it has been in the dealer's tank for at least a few days to
a week. This is especially important when dealing with damsels.
They are cheap and, unfortunately, are treated as such. Typically,
they are shipped in small bags with very little water to save
on freight charges. That means they are prone to suffer from
Post Traumatic Shipping Disorder, a term Morgan Lidster coined
to cover the broad number of reasons that an animal could
die shortly after shipping but of no apparent direct cause
(i.e., parasitic, bacterial, etc.) such as temperature extremes,
low dissolved oxygen, depressed pH and so on. Generally, once
they have remained in a dealer's tank for three days to a
week or more, I would consider them safe enough to purchase.
I would, however, still suggest that these fish, like any
other addition to the display, undergo a proper quarantine
period so that they are screened for disease, permitted time
to adjust to prepared foods and gain some weight before being
thrust into the competitive environment of the display.
Also, I do not suggest buying those tiny, cute little ones
that are occasionally offered for sale. Many times I have
seen damsels that are about as big around as a dime, sometimes
even smaller, and I avoid these specimens like the plague.
As with many fish species, the smallest and the largest individuals
should be avoided (Fenner, 2001). In my experience, the largest
adults often refuse to eat prepared foods. I believe they
have simply been in the wild for too long to adjust to life
in captivity. On the other hand, the babies that come through
the chain of custody have a high mortality rate, too. It is
my opinion that these are half starved by the time they get
to the local dealer's tanks where they may receive routine
feedings. Also, they don't tolerate shipping nearly as well
as slightly larger specimens.
Finally, I avoid specimens from a tank
containing other dead or dying fish. Whether the deaths can
be attributed to shipping problems, aggression, disease, etc.
makes little difference. All are signs that aquarists should
avoid specimens from that shipment or that dealer for the
time being.
Care:
Damsels, in general,
and Dascyllus species, in particular, are relatively
forgiving aquarium residents. They are not especially demanding
of water quality. Many times, these fishes are used to cycle
aquariums (a practice which I do not encourage), and consequently
they are exposed to high levels of ammonia and nitrite and
generally subjected to less than ideal conditions. But, many
times they survive and thrive nonetheless. It is a testament
to their hardiness and resiliency that they can be abused
in such a manner and still live. But as standard practice
for a conscientious aquarist, we should all remember that
we are talking about live animals and should strive to provide
them with the best environment possible.
They should be given plenty of cover so that they may setup
territories to defend. Ideally, they would have a natural
"host" to associate with, or at the very least,
a reasonable approximation. And, while most stores keep their
tanks crowded in an effort to minimize aggression, this is
only a short-term solution. For long-term, regular care, they
should be given plenty of room and overcrowding should be
avoided. Furthermore, be prepared to thin out the group. Usually
a dominant individual or pair develops if a small group is
purchased and introduced at the same time. This lone alpha
or top pair then typically goes on a rampage, aggressively
harassing all others of the same species. That is simply the
price to pay for keeping these fishes, so plans should be
made accordingly.
In general, damsels readily accept a variety of foods, and
Dascyllus species are no different. They are naturally
zooplankton eaters and as such should be offered similar substitutes
such as Mysis shrimp, Pacifica plankton, bloodworms,
Cyclop-eeze, and SweetWater Zooplankton (Daphnia).
I prefer to use frozen (and of course, thawed) or refrigerated
versions of the previous examples over the freeze-dried offerings.
I also routinely soak the foods in vitamin and lipid supplements
such as Boyd's Vita-Chem and American Marine's Selcon®.
It is also advisable to introduce some vegetable matter into
their diet. These fishes are substrate spawners (Fenner's
website) and are known for cleaning and eating various algae
from where they intend to lay their eggs. Introducing nori
and similar commercial algal preparations would be a good
idea for varying their diet. But, in reality, getting these
fishes to begin eating is rarely an issue. Of more pressing
concern is making sure their tankmates get something to eat
when housed with these voracious feeders.
Compatibility:
As I already mentioned,
these damsels are fiercely territorial. Care should be taken
in selecting appropriate tankmates for these fish. While they
should be housed with other fish that are equally as scrappy,
remember that to many marine predators, damsels are the aquatic
version of "popcorn" (Fenner, 2001). Many are bite-sized
tasty morsels that can easily be gulped down by groupers,
lionfish, eels and other predators.
Compatibility
chart for Dascyllus species:
Fish |
Will
Co-Exist
|
May
Co-Exist
|
Will
Not Co-Exist
|
Notes |
Angels,
Dwarf |
X
|
|
|
Should
co-exist well. |
Angels,
Large |
X
|
|
|
Should
co-exist well. |
Anthias |
|
|
X
|
Will
likely be harassed and/or killed by the damsel. |
Assessors |
|
|
X
|
Will
likely be harassed and/or killed by the damsel. |
Basses |
|
X
|
|
Will
be susceptible to damselfish attacks. |
Batfish |
|
X
|
|
Damsels
may harass batfish, attacking their excess finnage. |
Blennies |
X
|
|
|
Should
co-exist well. |
Boxfishes |
|
X
|
|
Slow
and unable to get out of the way, boxfishes are likely
to be excessively harassed. |
Butterflies |
X
|
|
|
Should
co-exist well. |
Cardinals |
|
|
X
|
Will
likely be harassed and/or killed by the damsel. |
Catfish |
X
|
|
|
Should
co-exist well. |
Comet |
|
X
|
|
Comet
will likely stay hidden more than usual. |
Cowfish |
|
|
X
|
Will
likely be harassed and/or killed by the damsel. |
Damsels |
|
X
|
|
Not
recommended unless paired individuals are obtained. |
Dottybacks |
|
X
|
|
While
likely battle to a stand-off if the sizes are similar. |
Dragonets |
|
X
|
|
Ignored
on most occasions. |
Drums |
|
|
X
|
Will
likely be harassed and/or killed by the damsel. |
Eels |
X
|
|
|
Should
co-exist well. |
Filefish |
|
X
|
|
Likely
to be harassed, especially Chaetoderma pencilligera. |
Frogfish |
|
|
X
|
May
attempt to consume the damsel. |
Goatfish |
|
|
X
|
Will
likely be harassed and/or killed by the damsel. |
Gobies |
|
|
X
|
Varies
greatly between species, but the majority will be harassed. |
Grammas |
|
X
|
|
Will
likely find a quiet corner and never move from it when
housed with damsels. |
Groupers |
|
X
|
|
Will
co-exist until they are large enough to swallow the damselfish. |
Hamlets |
|
|
X
|
Will
be susceptible to damselfish attacks. |
Hawkfish |
X
|
|
|
Should
co-exist well. |
Jawfish |
|
X
|
|
Not
recommended, but once established a jawfish can hide in
its burrow and escape damselfish attacks. May remain mostly
hidden in the presence of the more aggressive damsels. |
Lionfish |
|
|
X
|
May
attempt to consume the damsel. |
Parrotfish |
X
|
|
|
Should
co-exist well. |
Pineapple
Fish |
X
|
|
|
Should
co-exist well. |
Pipefish |
|
|
X
|
Will
likely be harassed and/or killed by the damsel. |
Puffers |
|
X
|
|
Another
slow mover that may be the object of frequent, repeated
attacks. |
Rabbitfish |
X
|
|
|
Should
co-exist well. |
Sand
Perches |
|
X
|
|
Aggressive
enough to hold its own, but the sand perch may consume
smaller damsels. |
Scorpionfish |
|
|
X
|
May
attempt to consume the damsel. |
Seahorses |
|
|
X
|
Will
likely be harassed and/or killed by the damsel. |
Snappers |
|
|
X
|
May
attempt to consume the damsel. |
Soapfishes |
|
X
|
|
Large
individuals may attempt to consume damselfish. |
Soldierfish |
X
|
|
|
Should
co-exist well. |
Spinecheeks |
|
|
X
|
Will
hide continually in the presence of an aggressive fish. |
Squirrelfish |
X
|
|
|
Should
co-exist well. |
Surgeonfish |
X
|
|
|
Should
co-exist well. |
Sweetlips |
|
|
X
|
May
attempt to consume the damsel. |
Tilefish |
|
|
X
|
Tilefish
do not mix well with aggressive fish. |
Toadfish |
|
|
X
|
May
attempt to consume the damsel. |
Triggerfish |
X
|
|
|
Should
co-exist well except with the most aggressive of triggers. |
Waspfish |
X
|
|
|
Should
co-exist well assuming the waspfish is unable to swallow
damsel. |
Wrasses |
|
X
|
|
Should
co-exist well except for the small docile wrasses. |
Note: While many of the fish listed
are good tankmates for Dascyllus
species, you should research each fish individually before
adding it to your aquarium. Some of the mentioned fish are
better left in the ocean or for advanced aquarists.
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Photo courtesy of Jay Copp.
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In addition to conflicts with other fishes,
be prepared for your Dascyllus to occasionally bite
you. Not only is this not unheard of, it actually is quite
common, for Dascyllus damsels to bite their owners
while the aquarist's hand is in the display doing normal tank
maintenance such as placing a new coral, rearranging the rockwork
or simply cleaning the viewing panes. Again, it is simply
the price of keeping these fishes.
Yet, with all generalizations, there are exceptions to the
rule. For instance, the Cloudy/Blue-Spot and Reticulated/Two-Stripe
humbugs are not as aggressive as the rest in this genus. But,
they are also are not as attractive, as readily available
or as hardy as the others, either.
Disease Considerations:
As a general rule,
Dascyllus are not known for being plagued by many diseases.
They, of course, can be infested with all the standard diseases
such as Cryptocaryon and Amyloodinium, but not
more so than many other fishes. A simple quarantine period
to screen for potential pathogens is all that is required
here. And, if a disease is detected, they respond well to
just about any treatment protocol: hyposalinity, copper, freshwater
dips and formalin baths (Fenner's website).
As further proof of their hardiness, Dascyllus damsels
have been reported to live over ten years in captivity (Fenner's
website).
All that is necessary is to select a reasonably healthy specimen,
screen it for disease, and provide a proper environment, and
aquarists will be rewarded with an aquatic pet for many years
to come, that cost only a few dollars to purchase.
Special Notes:
I mentioned in the
species breakdowns that these fishes are usually found in
close association with various cnidarians. This should be
no surprise to anyone who recognizes that these fishes are
closely related to clownfishes. Studies have even shown that
this relationship is beneficial to both animals (Liberman,
Genin, & Loya, 1995). The fishes obviously get a place
to hide to avoid predation, while the corals have been shown
to have increased growth rates as compared to other corals
grown without the humbugs. It was hypothesized that the fishes
provided nutrients from their waste material that fueled the
corals' growth. They also provide some extra water movement
in and among the dense coral branches that they dwell in during
the night, increasing dissolved oxygen content and again spurring
increased growth (Goldshmid, Holzman, Weihs, & Genin,
2004).
Conclusion:
These boisterous
fishes are definitely not for everyone or every display, but
their bold color patterns, hardiness and relatively inexpensive
purchase price do make them an attractive choice. All that's
needed is to plan accordingly for their special needs. And,
their bite is really not that bad. It scares more than it
actually harms you the first time it happens. After that,
you either get used to it or get some gloves.
All photos copyright Steven
Pro, except where otherwise noted.
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