JIGS vol3#1(9) (Read-Only) - Gobioid Research Institute

JIGS Vol. 3 No. 1
November 2003
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Classifieds
Goby food: Daphnia starter culture, $7 including shipping
within the US. All proceeds go to the IGS.
Email [email protected]
If you would like to place a goby-related ad in our quarterly
newsletter, send or email it to us and we will print it in the
next issue.
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Comments, Please
We’d like your comments! How do you rate our topic selection, writing quality, and overall quality of our newsletter (and
society)? What do you like? What do you dislike? What
would you like us to do differently? What topics would you
like us to cover in future issues? Please email comments to
the editor or write to:
International Goby Society
P.O. Box 329
Richland Center, WI 53581
USA
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Special Thanks
A very special thanks to Prof. Peter Miller, who has been
studying gobies for many years and who has kindly agreed to
be one of our scientific advisors.
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Cover photos: Top: A pair of Valenciennea strigata, a monogamous
goby species. Photo by Takahiko Mukai.
Bottom: Amblygobius phalaena, a non-monogamous relative of
Valenciennea. For more information on these two species see our Goby
News feature on pages 20-21.
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The Journal of the
International Goby Society
Vol. 3 No. 1 November 2003
JIGS Vol. 3 No. 1
November 2003
ISSN 1543-7744
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The Journal of the International Goby Society (JIGS) is the
quarterly publication of the International Goby Society (IGS). Non-profit
organizations may reprint articles, however we ask that you contact the
editor before doing so.
Editor: Naomi R. Delventhal
[email protected] or [email protected]
International Goby Society, P.O. Box 329, Richland Center, WI 53581,
USA
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Our scientific advisors:
Dr. Helen K. Larson Indo-Pacific and Australian Gobies
Dr. Richard Winterbottom Indo-Pacific Reef Gobies
Dr. James L. Van Tassell Atlantic and Eastern Pacific Gobies
Dr. Robert A. Patzner Mediterranean Gobies
Dr. Peter J. Miller General Gobiology
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Contents
Editor’s Introduction……………………………………….3
Goby Queries…………………………………………...….4
A Conservation Note on Japanese Freshwater Gobies…….9
By Dr. Takahiko Mukai
Mudskippers: The Periophthalmus Species, Part 4……….12
By Richard Mleczko
Mogurnda mogurnda……………………………………..16
By Roger Pontes
Goby News…………………………………………...…...20
Volume 2 Index…………………………………………...22
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JIGS Vol. 3 No. 1
November 2003
Vol. 2 # 4, July 2003
Introduction (thanks to readers, Gobiodon rivulatus)
Goby Queries (Gobiodon, sexing bumblebee gobies,
Gobioides broussoneti)
The Periophthalmus Species, Part 3 (P. barbarus)
The Round Goby
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Back issues available for $3 each (includes shipping). If you
would like an electronic copy of the text of a specific article,
send a request to the editor (no charge).
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News and Notices
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Newsletter Exchanges
The IGS will exchange newsletters with other clubs and
organizations interested in gobies. If you belong to a group
interested in exchanging newsletters, send an email to the
editor. We can also offer reduced subscriptions to members
of a club if the newsletters are all sent to the same address.
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Notice to Authors
We consider articles on any aspect relating to gobies
(suborder Gobioidei); their care and breeding in captivity,
their natural history, etc. If we print an article, the author
receives credit towards a one year IGS membership. If you
have a goby aquarium you would like to see featured in our
Goby Tanks section, please send photographs or scanned
(.jpg) images to the editor. Thank you!!
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JIGS Vol. 3 No. 1
November 2003
JIGS Volume 2 Index
Vol. 2 # 1, September 2002
Introduction (new features and advice to authors)
Goby Queries (Tateurndina ocellicauda, striped
gobies, the name Eleotridae)
Desert Gobies: Sneakers, Pink Mutant
Goby News (blind goby, Karsten totoyensis)
The Pleasures of Watching Gobies Sift
Mediterranean Gobies
Goby Tanks (10 gal. with desert gobies)
Vol. 2 # 2, December 2002
Introduction (deep-water Priolepis)
Goby Queries (bumblebee gobies, Cryptocentrus,
Stigmatogobius sadanundio)
The Crested Mud Goby (Cryptocentroides cristatus)
The Periophthalmus Species, Part 1
Goby Tanks (5 gal. with Brachygobius)
Goby News (Protogobius)
Vol. 2 # 3, March 2003
Introduction (Gobiosoma ginsburgi)
Goby Queries (Amoya sp., Lythrypnus dalli)
Goby on a Cup
Goby News (microhabitats)
The Shortest of Them All
The Periophthalmus Species, Part 2
(P. argentilineatus)
Goby Tanks (Australian natives)
JIGS Vol. 3 No. 1
November 2003
Editor’s Introduction
Recently my mother stopped in at my favorite aquarium store.
“Are you Naomi’s mother?” asked one of the clerks. “Do you
know anything about gobies? We just got some unknowns.
They’re in the back, being treated for fungus.”
My mother said she didn’t know anything about gobies, but she
decided to look at them, because she really does know something! Afterwards she described them to me. “They are small
and have almost transparent bodies, but their mouths are similar
to those of bumblebee gobies.” I mentioned a number of gobies
with mouths similar to bumblebee gobies (a rather typical mouth
shape for small gobionellines) but none were exactly what she
saw. So the next day I went to see what they were.
I am accustomed to being astonished by gobies, but I wasn’t
really expecting what I saw. They were five desert gobies
(Chlamydogobius eremius), but not the usual desert gobies—
they were lacking dark pigments so the general coloration was
pink! Interestingly, the dominant male still had slight yellow
shades and some blue on the first dorsal fin. I am usually the
type of aquarist who likes fish the way they are found in nature,
but I could not resist buying these, as I wanted to see how the
mutation breeds.
Many readers will remember a letter published last year from
Martyn Robinson describing a pink mutant desert goby in a
display tank. Apparently that was not an isolated case, as they
are now available in the trade. This is the first example I know
of a “fancy” variety of goby being traded - probably few have
been bred because gobies are not highly sought after and are
usually difficult to breed. If any readers are aware of other
artificial forms I would be very interested to hear of them!
Naomi Delventhal
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14 November 2003
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JIGS Vol. 3 No. 1
November 2003
Goby Queries
Mystery Gobies, Goby Books
Q. I bought the goby in picture #1 for my mom about 6
months ago. He is sort of goldish-cream color with varying
shades of brown markings. He does spend a lot of time on the
tank bottom, but
lately, as he has
grown to a whopping 1 1/4 inch, he
has been hopping
around from leaf to
leaf and spending a
lot of time living
on plants. He
doesn't seem to eat
them and is more inclined to dine on live blackworms, live
brineshrimp, and frozen bloodworms and brineshrimp.
Hopefully you guys have a clue as to what kind of goby he is.
Any info on him would be welcome as he is a favorite guy.
The 2nd drawing is of a "red goby" (this is what the fish store
called them) and the red goby's mate. I was told these guys
are algae eaters - which they very actively are - however they
also enjoy live blackworms, brineshrimp, sinking carnivore
wafers and algae wafers. I've also seen them eating scraps of
"sheet" seaweed. They don't seem particularly social with
each other, but they also don't fight or chase each other away.
They are also diggers, but tend to dive into the substrate headfirst, instead of grabbing mouthfuls of gravel and spitting it
out like my white cheek goby. I was told these guys would
grow to about 4 inches in length. The male has mahogany red
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JIGS Vol. 3 No. 1
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When fish were experimentally widowed, they would remate
very quickly, but usually their new mates were slightly
smaller than their original mates. Often the new mates had
been previously mated but abandoned their own former mates
which were smaller or had just spawned.
The researchers discovered that females with larger mates
spend on average less time burrowing and more time feeding.
Apparently females benefit by having large mates, since large
males can burrow more efficiently than smaller ones. So it
would be advantageous for females to guard their large mates
from other females.
Males are able to defend their mates against most intruders.
Larger females are also preferred by males, presumably
because of their greater fecundity. Nearby females often
spawn simultaneously, which discourages desertion by males.
A closely related goby species, Amblygobius phalaena, has a
different mating system. In this species one large male
maintains a burrow around a coral head with multiple females
living nearby. Unlike female V. strigata, these females do
not compete for mates. Because burrow substrate and
available males are limited, this species does not exhibit
monogamy.
For more information see:
Reavis, R.H. and G.W. Barlow. 1998. Why is the coral-reef
fish Valenciennea strigata (Gobiidae) monogamous? Behav.
Ecol. Sociobiol. 43: 229-237.
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Goby News
Monogamy in Gobies
Aquarists and divers have long observed that certain species
of gobies form long term pair bonds. Well-known examples
include Signigobius biocellatus, the twinspot or crabeye goby,
and Valenciennea strigata, popularly known has the yellow
headed or blue banded goby. In nature, V. strigata live in
pairs. Each pair maintains a territory that contains
burrows for nesting and protection and sandy areas where
they forage by sifting through large mouthfuls of the
substrate.
One of the traditional explanations for monogamy is that it
facilitates biparental care. Biparental care can be advantageous, because if both mates stay together and raise the
young, theoretically more will survive. But in V. strigata only
the male cares for the eggs, as is typical of gobies.
In some coral reef fishes, monogamy is associated with
limited resources or a shortage of potential mates. The
advantages of staying together would be that the paired fish
could defend a better territory, or that individual fish could be
assured of a mating partner at all times. But in a recent study,
Robert Reavis and George Barlow tested the predictions of
these models in V. strigata, and suggested an alternative. In
their model, resources and potential mates are abundant, but
individual fish guard their mates by chasing away others of
the same sex, thus monogamy is enforced. Using a number of
elegant experiments, they tested the predictions of this model.
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JIGS Vol. 3 No. 1
November 2003
fins when he feels
the urge to be
colorful - otherwise
they are fairly clear.
He has a whitish area
under his chin, which
goes completely
white under his belly.
He is a medium to
light grey with
darker brownish (taupe) stripes. The striping of his fins is
black which and he has black spots on his back which run the
length of his body. There are no black marks on his dorsal or
pectoral fins. The female is very white with black markings.
She has one iridescent pink spot on the bottom of her gills.
The only other variation of the black and white color is the
top of her head, where, level with her eyes and sweeping
upward running almost exclusively along her backbone, is a
light grey color. Below this are somewhat v-shaped markings
in black and below that are very fine criss-crossing black,
lines, which run down the solid black stripe that bisects her
body. She has no visible markings on her fins. Her behavior is
much the same as the male, except neither she nor my other
female seems able (or inclined) to darken or lighten her
coloring.
I've been looking for a good (or any) goby book for a year and
a half and have yet to find one. If you have any suggestions
(other than the 3 volumes of Baensch Aquarium Atlas),
(which I still plan on buying soon, but their info is scattered
and sometimes somewhat vague) I'd appreciate it.
Christine R. McNeill
Flint, Michigan
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JIGS Vol. 3 No. 1
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A.
First I’d like to commend you for your careful drawings
and thorough descriptions of coloration and behavior.
Unfortunately it’s often very difficult (if not impossible) to
identify gobies by their coloration alone. There are over
2000 goby species and it’s not unusual to find species that
have similar coloration even though they are not closely
related. Often these gobies can be distinguished in photographs by subtle differences in body or head shape, scale size,
etc. - characteristics not easy to capture in a drawing. But
sometimes one needs the actual specimen to determine its
identify.
JIGS Vol. 3 No. 1
November 2003
be fed a minimum of once a day, (3) if you miss a day with
the infusoria, you will lose the fry, (4) the fry need plenty of
infusoria, (5) when they start growing (and they do grow
slowly) you will need a magnifying glass to observe them
while they are eating to determine if they are eating the baby
brine shrimp that you are adding to the tank, (6) once they
start eating the shrimp you are “over the hump.”
References
Allen, G.R., S.H. Midgley, & M. Allen. 2002. Field Guide to
the Freshwater Fishes of Australia. Western Australia Museum.
When I look at picture #1, I see a general color pattern that is
common to many kinds of gobies, even ones that aren’t
closely related to each other. So without seeing the actual
fish, I could only make a guess as to what it may be. In fact,
this is a color pattern that is common to many types of small
fishes, for example North American darters, which are
occasionally sold as gobies. (You can distinguish darters
from gobies by the presence of a lateral line, a first dorsal fin
usually with a longer base, and unfused pelvic fins.)
Axelrod, H. R. 1967. Breeding Aquarium Fishes. T.F.H.
Publications. Neptune City, New Jersey.
Your red goby, however, I am more confident in suggesting
that it is a sicydiine, probably a species of Stiphodon, since
they often show a high degree of sexual dichromatism (i.e. the
males and females have different coloration). They also have
the general body shape as shown in your drawing. The adults
of these small (usually less than two inches) Indo-Pacific
gobies typically live in freshwater streams with some current
Roger Pontes has been an aquarist for approximately 20 years
and now maintains 70+ tanks. He has bred over 140 species of
fish, which include cichlids, killifish, livebearers, antabantoids, tetras, catfish, North American natives, rainbows, and,
of course, gobies.
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Leggett, R. & J. R. Merrick. 1987. Australian Native Fishes
for Aquariums. J.R. Merrick Publications, Australia.
Sterba, G. 1969. Freshwater Fishes of the World. The Pet
Library, New York.
About the Author
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would Corydoras catfish eggs. As they were scraped off, I
collected them into a small plastic container. You guessed it they all died!
No big thing! During the next 24 weeks I had twenty-two
clutches. During this time period I noticed that they need a
high protein food - if I fed them live blackworms, I would get
a spawn. Allen et al. (2002) report that M. mogurnda spawn
during the rainy season (November to March). It’s the old
story about fish not reading books, because my fish spawned
from February to July (and are still continuing to
spawn). Some weeks would be dry weeks with no eggs, but
other weeks I would have two batches in one week, so it was
pretty obvious that more than one female was involved. They
always spawned in the morning (approximately 7:00 - 8:00
A.M). A couple of times I was doing water changes on my
other tanks and they just went on with their business laying
eggs as though I weren’t even there. They are different from
cichlids in that they do not bother to clean off the surface they
are laying eggs on. They lay eggs right on top of the algae
covered flowerpots, etc.
Stiphodon percnopterygionus, male (above) and female
(below), collected from Ogasawara, Japan. Note the sexual
dimorphism and dichromotism. Photo by Takahiko Mukai.
Whenever they laid eggs on a flowerpot, slate, or filter tube, I
removed the eggs. They seemed to have a preference for slate
that was leaning against the glass. Sometimes I pulled the
eggs the first day, other times the second or third day. I
always kept a piece of airline tubing bubbling in the tank
holding the eggs.
I tried a number of different approaches to raising the fry - the
majority being unsuccessful. In fact, I’m still not sure as to
the best formula. My conclusions: (1) You definitely need
infusoria to feed the fry when they hatch, (2) the fry need to
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Notes on Breeding
and feed on a variety of food items, including algae. There
are more than two dozen nominal species and new species are
still being discovered in places such as Papua New Guinea.
They do well in medium sized tanks with clean water and
some current.
I am not aware of a better aquarium source for goby
information than the five volumes of Baensch. (Only the first
three are available in English, but the Photo Index includes
the species from all five volumes.) I remember a few years
ago, being in your situation, and looking everywhere for good
aquarium books on gobies! I don’t do that much anymore,
partly because I’ve read most of the books and kept most of
the popular species, but even more so because I’ve come to
rely a great deal on scientific works and regional (rather than
specifically aquarium-related) books on fishes. These works
often include information on the habitats and life histories of
the fishes - information that is directly useful to aquarists.
You should be able to get some of these types of sources
through a university library or interlibrary loan.
Some general advice: Keep in mind that many species of
gobies have rarely been kept by aquarists. So an experienced
goby hobbyist learns to make careful observations of
behavior. Sometimes it’s necessary to experiment with
different water conditions, such as salinity, or different foods.
However, if your fish are doing well in the conditions you
have provided, there is no need to change them!
8
The new fish were initially placed with some other species in
a 40 gallon tank, with an undergravel filter, some rocks, clay
pots, and a couple of sponge filters. The water parameters
were a temperature of 78 degrees and a pH of 7.8. A tablespoon of Kosher salt was added per five gallons of
water. Nothing spectacular happened; the M. mogurnda ate,
and they grew. They swam in the lower half of the tank,
usually on the bottom of the tank.
According to Axelrod (1967), they will reach a size of as
much as 8 inches and begin breeding at 2 inches. When my
M. mogurnda were over 4 inches long, I became serious about
breeding them and placed them by themselves in a 30 gallon
tank. The setup I used for breeding was the same as the 40
gallon; the only difference was that I changed the amount of
salt added to their water. I began adding two tablespoons of
salt per gallon. However, Sterba (1969) states in his book that
M. mogurnda should be kept in fresh water. Since they also
can be kept as brackish water fish, it appears that they may be
kept in a number of different water conditions.
A short time after setting up the breeding tank, I was surprised
to see a clutch of approximately 300-400 eggs each attached
by filaments to the glass. It appeared that the male was
fanning the eggs. The way the eggs wavered as he fanned
them reminded me of a wheatfield in the wind. In fact, he
was actually touching the eggs with his pectoral fins.
I didn’t want to remove the other M. mogurnda that were in
the tank and I was afraid that when the fry hatched they might
get lost in the gravel. So I experimented. I took a single
edged razor blade and scraped the eggs off the glass like you
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JIGS Vol. 3 No. 1
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Mogurnda mogurnda
by Roger Pontes
[email protected]
Over the years I have seen Mogurnda mogurnda for sale in
some of the pet stores I have visited. In fact, I have owned
them a couple of times, but at these times I was not serious
about breeding them. Well, approximately a year ago I came
across M. mogurnda at a pet store and purchased six of them
to breed. When I picked out the fish, it appeared to me that
the males had more coloring, their colors were more intense,
and they were larger. Hence, I bought what I thought were
three pairs, and all indicators suggest that I was successful. However, be careful when choosing your fish, because
the color does vary with each individual and will change
according to their mood.
In the Wild
These fish are native to the coasts, rivers, creeks and quiet,
slow flowing bodies of water of central, northern, and eastern
Australia and New Guinea. There is a great deal of variety
within M. mogurnda, and some wild populations, for example
the Barkly Tableland (Northern Territory) population, may
someday be determined to be separate species* (Allen et al.,
2002).
*Note from editor: For information on the distribution and taxonomy of
Mogurnda, see: Allen, G.R. and A.P. Jenkins. 1999. A Review of the
Australian Freshwater gudgeons, Genus Mogurnda (Eleotridae) with
Descriptions of Three New Species. Aqua, 3(4):141-156.
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Mudskippers The Periophthalmus Species
Part 4
Periophthalmus chrysospilos
By Richard Mleczko
[email protected]
Species identification: Bleeker 1852.
Species name: The name chrysospilos is from the Greek
chryso (meaning gold), and spilos (meaning spotted), in
reference to the gold or orange spots on the side of the body
and head.
Common names: Gold-spotted mudskipper.
Other used names: chrysopilos (misspelling).
Distribution: Brackish mangrove and nipa palm areas from
the east coast of India to the Gulf of Thailand and Java Sea.
Distinguishing features: The first dorsal fin has a long
orange first spike and orange, black and white in the fin itself.
The second dorsal fin has a red edge followed by a horizontal
black stipe. The face and body are covered in brilliant orange
(gold) spots. Fused pelvic fins form a sucker disk.
Physical characteristics: Typical length range 5 to 16 cm,
weight 6 to 25 g. First dorsal fin has 7 to 10 spines, second
dorsal fin has 12 to 13 elements. Anal fin has 11 to 13
elements.
Sexual dimorphism: Males have two long orange primary
spines in the first dorsal fin, females have only one long
orange spine which is shorter than the male's. During the
mating season males develop a red or golden chin.
Aquarium suitability: Very good.
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JIGS Vol. 3 No. 1
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Below:
Lake Biwa is the largest lake in Japan and one of the
oldest lakes in the world. It is known for its beauty and its
many endemic species found nowhere else.
Photo by Takahiko Mukai.
Photo by Edward Murdy
Periophthalmus chrysospilos featured in the literature:
Compiled by Richard Mleczko
Ip, Y.K., S. F. Chew and W.P. Low. 1991 Effects of hypoxia on the
mudskipper, Periophthalmus chrysospilos. Journal of Fish Biology, vol 38.
Ogasawara, T. et al. 1990. Changes in prolactin cell activity in the
mudskipper Periophthalmus chrysospilos in response to hypotonic
environment. Zoological Science (Tokyo), vol 8(1).
Low, W.P. et al. 1990. A comparative study of the gill morphometry in the mudskippers Periophthalmus chrysospilos, Boleophthalmus boddaerti and Periophthalmodon schlosseri. Zoological Science (Tokyo), vol 7(1).
Chew, S.F. and Y.K. Ip. 1990. Differences in the responses of two
mudskippers, Boleophthalmus boddaerti and Periophthalmus chrysospilos to changes in salinity. Journal of Experimental Zoology,
vol 256.
Ip, Y.K. et al. 1990. Changes in the lactate content in the gills of
the mudskippers Periophthalmus chrysospilos and Boleophthalmus
boddaerti in response to environmental hypoxia. Journal of Fish
Biology, vol 36.
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For much more information on Japanese gobies and other
gobies, visit the author’s website, Mukai’s Encyclopedia of
Goby. Although the text is mostly in Japanese, the site is
easy to navigate and it is well worth looking at for the
photography alone.
http://homepage2.nifty.com/PhD-mukai/
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Chew, S.F. et al. 1990. Can the mudskipper Periophthalmus chrysospilos tolerate acute environmental hypoxic exposure? Fish
Physiology and Biochemistry, vol 8.
Ip, Y.K., S. F. Chew and R. W. L. Lim. 1990. Ammoniagenesis in
the mudskipper, Periophthalmus chrysospilos. Zoological Science,
vol 7(2).
Low, W.P. et al. 1988. A comparative study of terrestrial adaptations of the gills in three mudskippers - mudskippers Periophthalmus chrysospilos, Boleophthalmus boddaerti and Periophthalmodon schlosseri. Biological Bulletin (Woods Hole, Massachusetts),
vol 175.
Above and below:
Rhinogobius sp. BW (Lake Biwa type)
This undescribed species lives in Lake Biwa, and unlike some
other species, does not travel upstream to rivers.
Photos by Takahiko Mukai.
Lee, C.G.L. et al. 1987. Environmental effect on plasma thyroxine
(T4), 3,5,3’ –triodo-L- thyronine (T3), prolactin and cyclic adenosine 3’ ,5’ –monophosphate (cAMP) content in the mudskippers
Periophthalmus chrysospilos and Boleophthalmus boddarti. Comparative Biochemistry and Physiology, vol 87A.
Lee, C.G.L. et al. 1987. Na+, K+ and volume regulation in the mudskipper, Periophthalmus chrysospilos. Comparative Biochemistry
and Physiology, vol 87A.
Polunin, I. 1972. Who says fish can’t climb trees. National Geographic Magazine, vol 141.
Photo by Toru Takita
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JIGS Vol. 3 No. 1
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A Conservation Note on
Japanese Freshwater Gobies
By Dr. Takahiko Mukai
Bioscience Bldg. 102, Department of Integrated Biosciences,
Graduate School of Frontier Sciences, The University of Tokyo,
5-1-5, Kashiwanoha, Kashiwa, Chiba277-8562, Japan
[email protected]
Some of the most problematic invasive species in Japan are
introduced sunfishes (family Centrachidae). These species eat
many native fishes and insects (e.g. endemic dragonflies), and
cyprinid fishes are decreasing in areas where they are present.
A report from Miyagi Prefectural Fisheries Experimental
Station (http://www.pref.miyagi.jp/naisuisi/ (in Japanese))
showed that Acheilognathus typus (a cyprinid), Oryzias
latipes (the ricefish), Rhinogobius sp. and Gymnogobius
castaneus (sensu Stevenson, 2003) had disappeared in the
research capture since largemouth bass appeared. Major goby
species in the Japanese inland waters include those of the
genera Rhinogobius, Tridentiger and Gymnogobius.
G. castaneus is the smallest and most limnetic one, thus this
goby species may became the easiest prey to the sunfish.
After a native community was changed by introduced
predators, Rhinogobius sp. (orange type) populations usually
survived, but the gobies were eaten by the bass (Yodo and
Kimura, 1998). There are a number of other fisheries reports
about the impacts on native communities, but all of them are
written in Japanese.
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The largemouth bass and the bluegill are outbreaks in Lake
Biwa, an ancient Japanese lake which has many endemic
fishes, and some cyprinids have decreased. This case is
similar to the Nile perch in Victoria Lake, but, fortunately, the
endemic gobies (Rhinogobius sp. Lake Biwa type and
Gymnogobius isaza) have survived, at least for the present .
Literature:
Yodo T. and S. Kimura. 1998. Feeding habits of largemouth
bass Micropterus salmoides in Lakes Shorenji and Nishinoko,
Central Japan. NIPPON SUISAN GAKKAISHI 64: (1) 26-38
(In Japanese, with English abstract.)
Gymnogobius isaza, a goby native to Lake Biwa.
Photo by Takahiko Mukai.
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