| |
Fish Coloration, and stress, Chromis - 7/24/08
Hey crew
Good day to you all, I hope all is well.
<Hello! The same to you!>
I have a quick question that I looked and looked on the site for the answer but
had no luck. I may be looking in the wrong place, but I thought I would ask
anyway.
<Okay>
So I have a little green chromis that shares a 60gal with two big chromis. Well,
the little guy has always had a blotchy or spotty looking coloration but his
behavior seems normal. When I put the first chromis in the tank to help cycle
the tank he also appeared like this as well, but shortly grew out of it. My
question is what causes this coloration? He does get picked on by the other two
a little, but nothing that keeps him from strutting around the tank and eating
everything I put in. I read the articles about why and how fish change color and
the various types (cited here:
http://www.wetwebmedia.com/AqSciSubWebIndex/coloration.htm). Well, the concern I
really have is more related to my Kole Tang that has been in the tank for about
three weeks now and doing great.
<Needs more space...>
Although, this morning, I turned the lights on earlier then usual, and his
coloration looked blotchy and spotty like the chromis. I immediately put a pinch
of pellet food in and he gobbled it up. I took a shower and got ready for work
and went and checked on him (about 20 minutes overall). He was fine. Color back
to normal and active as usual. I took two samples of my water today to check at
my LFS on my lunch. I figure maybe I have a water quality issue, so I will have
it checked and do a water change tonight (which I regularly do every other
week). Now I have never noticed this before on him, although, he is a bit
skittish still. He is the man of the tank. The other fish leave him alone and
somewhat "run" the other way when he comes around except for the maroon, they
seem to have become friends. I did introduce two new fish to the tank a few days
ago. They were a Orchid Dottyback and a Lawnmower Blenny.
<Quarantined?>
I do know that the Orchids can be a touch ornery, but I have yet to see him
since he was added. Could he be causing stress to the tang for a change of
coloration? Well I hope this was enough information. Thanks for your time and
constant attention to helping people like me.
<I'd say this is most likely stress due to crowding or water quality issues- do
see about a larger home for that tang, as well as quarantining new arrivals for
4-6 weeks. Water changes and the works as well, varied feeding...general stress
most likely the culprit here.>
Spencer
<Benjamin>
Re: Fish Coloration - 7/24/08 – 7/30/08
Am I over crowded due to the amount of fish in the tank?
<Not really, more just a little cramped for a fish that swims in long spurts>
I read on wet web that they need a 50-60 gal tank. So who should I get rid of to
make him happier?
<He's probably not miserable, although this isn't ideal...I think it's a good
excuse to keep in the pocket for a tank upgrade later on...>
He shares his tank with three blue chromis, 1 Dottyback, 1 lawnmower, and 1
maroon. All of those fish are relatively small. Also, if I start to use Selcon
will that help his immune system overall, that it may help this problem?
<Sure couldn't hurt. Better nutrition can help with stress and coloring
problems>
I did do a 3 week quarantine with those two new additions, they were also at the
LFS for about 2 months before I purchased them.
<Glad to hear it...good job>
I am nervous about this because I am taking a three week vacation out to LA and
don't want anything bad to happen.
<I don't think this sort of chronic trouble will cause trouble of an acute sort
so soon...but do see about amending nutrition, water quality. Also check to make
sure none of these fish are harassing each the other.>
Thanks for your help.
Spencer
<No problem! Benjamin>
Re: carotenoids and seahorses 5/16/07
Dear Bob:
<Pete!>
So that's what gives the Garibaldi their brilliant coloration -- those dazzlers
really stand out in a kelp forest like neon signs!
<Ah, yes... am particularly fascinated by the more-shallow water juveniles with
their brilliant blue highlights>
That's a fascinating subject (certainly the habitual sponge eaters are among
the most vividly colored of all the marine fish).
<Yes... had a few conversations with friend and fish-food maker Chris Turk years
back... trying to convince him to investigate, incorporate such material/s in
his frozen fish food prep.s... With some success. Always strikes me as strange
that folks don't consider/realize that with so much of a given material present
(e.g. live coral polyps) that there should not be predators about...>
No one has done a similar study specific to seahorses to my knowledge. The
Vibrance enrichment formulas developed for Ocean Rider specifically to meet the
long-term nutritional requirements of seahorses include pure Astaxanthin and
other carotenoids as key ingredients, no doubt based largely on information
from papers such as yours. I would like to read your Garibaldi paper sometime
if it's available.
<Can, will look through my old files if you'd like... Not keyed/computerized, so
if you'll send a FAX number along...>
Best of luck with all of your projects, sir!
Respectfully,
Pete Giwojna
<And you and yours my friend. Life to you. Bob Fenner>
Hi Everyone,
Attached is a paper about mimicry in coral reef fish. 10/29/06
I would
especially like to thank Erik Schlogl and Bob Fenner for allowing me to
use their photographs.
Best Regards
Ashley Frisch
James Cook University.
Dear Author
PDF offprints
Blackwell Publishing is pleased to advise you that a PDF file of your
paper is attached to this email.
Please note that this replaces the procedure of sending free offprints
by post.
If you have any queries please contact the Production Editor at:
mae@oxon.blackwellpublishing.com
PDF Terms & Conditions
Please note the following Terms and Conditions regarding the use of the
attached PDF file of your Article. Use of this PDF file indicates
consent to these Terms and Conditions.
Provided that you give appropriate acknowledgement to the Journal and
Blackwell Publishing, and give full bibliographic reference for the
Article, and as long as you do not sell or reproduce the Article or any
part of it for commercial purposes (i.e. for monetary gain on your own
account or on that of a third party, or for indirect financial gain by a
commercial entity) you may use the PDF, in the following ways:
o you may share print or electronic copies of the Article with
colleagues;
o you may use all or part of the Article and abstract, without
revision or modification, in personal compilations or other publications
of your own work;
o you may use the Article within your employer's institution or
company for educational or research purposes, including use in course
packs.
Please note that you are not permitted to post the Blackwell Publishing
PDF version of the Article online.
Self-archiving of author manuscripts
. Submitted version: You may post the original manuscript of the
Article, as submitted for publication in the Journal, on your own
personal website, on your employer's website/repository and on free
public servers in your subject area. We ask that as part of the
publishing process you give appropriate acknowledgement to the Journal
and Blackwell Publishing. You agree not to sell or reproduce the Article
or any part of it for commercial purposes (i.e. for monetary gain on
your own account or on that of a third party, or for indirect financial
gain by a commercial entity).
. Accepted version: Twelve months after publication you may post
the original manuscript of the Article, as originally submitted for
publication in the Journal, and updated to include any amendments made
after peer review, on your own personal website, on your employer's
website/repository and on free public servers in your subject area.
Appropriate acknowledgement to the Journal and Blackwell Publishing, and
full bibliographic reference for the Article must be given. In addition
you agree not to sell or reproduce the Article or any part of it for
commercial purposes (i.e. for monetary gain on your own account or on
that of a third party, or for indirect financial gain by a commercial
entity). The electronic version must include a link to the published
version of the Article together with the following text: 'The definitive
version is available at www.blackwell-synergy.com
<http://www.blackwell-synergy.com/>
'
For additional information regarding any use of this PDF file not
covered by these Terms and Conditions, please refer to the Blackwell
Rights Department at: journalsrights@oxon.blackwellpublishing.com.
Use of this PDF file indicates consent to these terms and conditions.
mae_103.pdf (Binary attachment)
The Physiology and Behavior of Color in Fishes information 7/5/06
Dear sir:
I am interested in the article : The Physiology and Behavior of Color in Fishes,
but it seems no author's information.
Could you tell me ?
<I am the author of this survey piece... It is quite old. Bob Fenner>
Sincerely,
Cheng Bang Chu
Re: Goldfish turns yellow! - 03/22/06
Dear Bob,
<Teti>
Thank you for your e-mail. I'm glad to hear that there
is nothing wrong with the fish. Could you explain
though why this is happening?
<Mmm, maybe... Turns out, the mechanism/s that determine color and reflection in
Goldfish breeds are not "well fixed"... and that some are becoming more random
w/ lack of detail by breeders. Due to whatever influences... water quality,
nutrition mostly, along with genetic (pre)disposition, some do change color...
mainly "reverting" back to browns of sorts (their "natural color"), but some
white, some even mottled/mosaics... Makes sense teleologically that there should
be such "drift", as there is demonstrated survival value (being able to avoid
predation by "blending in")...>
I visited the link you sent me and we will try to
enrich the diet of the goldfish. We've started feeding
them blanched courgettes and spinach.
<Ah, good>
Once again,
Thank you!
Teti
<Welcome. Bob Fenner
Color change 12/21/05
From the references in your excellent web pages on color in
fishes, can
you tell me what the letters "TFH" and "FAMA" stand for? I'd
like to look
up these references. <Richard, they are magazines. Tropical
Fish Hobbyist and Freshwater and Marine Aquarium.>
Thanks, <You're welcome. James Gasta
Richard Ellis <<... THE R. Ellis? RMF>>
Ultrafluorescent 9/7/05
Hi friends:
We live in Baja Sur, Mexico... so far on the ocean at night, and not always
there are special things that shines very brightly, specially related with the
movement...nobody here knows the name of this parasites, fish, who knows....
They are supposed to shine more on bays, near the rocks or at the shore, but
even if you inside the ocean they are by tons, they leave like a wave of
glitter....so nice, so peaceful...
By any chance, do you know the name of these things?
We would appreciate your help
Regards
Hugo and Josefina
<There are many phosphorescent organisms in the sea... some are indeed
spectacular... the most common in Baja are largely algae that "sparkle" when
disturbed by surface activity. Bob Fenner>
The Ethics of Glo-Fish (TM) (6/5/05) Hiya Bob, <<Howdy. RMF>>
I just finished reading the article on the Glo-fish, and I was wondering if
it would be possible to ask the author if he considers every breed of dog, most
breeds of milk and beef producing cattle, and probably 80% or better of all of
the grains and fruits he eats as also being 'garbage' due to the fact that they
are also man induced 'mutations' (yes, the method may be different, but the
intent and process is the same and similar-one is just more 'trial and error,
after all, no?) For the record, I also don't like the idea of Glo-fish, or
painted chandas, but plenty of folks hate telescopes, black moors, fancy guppies
and swords for just as legitimate reasons. <Agreed> I can understand a POV of
distaste and dislike, I was just wondering what selective bias the author uses
to determine which of our obvious genetic alterations are 'garbage' and why? ;)
(heh, maybe I should write a counter point article for submission, playing
devil's advocate) <All submissions are welcome for consideration. You will have
to use a lot better grammar than you did in this e-mail. Please capitalize the
proper noun "I" and the first letter of sentences. We post all e-mails and
replies. It's a lot easier for folks to read them if they are punctuated
properly. If you do it then we can spend less time proofreading and more time
answering.> Keep up the good work-been observing your website for years, all the
best!
Alan
<Thanks. The author of the article is not a member of the question-answering
crew, so I do not know how to contact him. I do agree with you on this issue. I
have nothing against Glo-Fish (TM) myself. They were created to serve a
utilitarian purpose (pollution detection). If there is a side benefit of
providing pretty fishes that have not been chemically burned and dyed, that's
great from my perspective. I have no problem with GM foods either. I say you're
right that there is no difference in principle between this and selective
breeding. It's only method and speed. In fact, GM is better because the planning
will lead to fewer bad mutations. It just needs to be properly regulated. As for
the other fish you mention, I have qualms about some of them. If fish are
selectively bred for appearance, I only have a problem if that creates a
deformity that impairs the fish or causes pain. Some of the fish sold these days
definitely suffer as a result of their selectively-bred appearance. That's my
opinion, for what it's worth. Steve Allen>
Question: behavior of color
Dear Dr. Fenner,
<Just Bob please, I have no doctorate>
I enjoyed reading your article on The Physiology and Behavior of Color in
Fishes.
I am writing a children's book on albino animals. I am trying to understand
leucism, which according to my research
is defined as white or weak coloration.
What causes leucism? Is it due to less pigment, less or abnormal
chromatophores, or by the movement of pigment to different layers of the
epidermis?
<Is of genetic disposition. A partial expression of color... imagine a
multi-gene trait with only part passed on to offspring... and conditions
allowing the presences of said young (most are eaten due to lightness of color
by predators)>
Thank you for your time. I appreciate your help and will give you credit in my
book.
Sincerely,
Randi
<Thank you my friend. Bob Fenner>
Re: question: behavior of color
Hi Bob,
Thank you for writing.
So, would I be correct in saying: "In leucism, melanocytes function
abnormally. Although the vast majority of melanocytes is defective, many
leucistic animals have certain areas of normal coloration, as in their eyes
or on their faces."
Again, thank you for your help.
Randi
<Actually, no... the actual color cells that are present do function normally...
but through inheritance, leucistic animals have partial to complete (even non
bilateral) absence of said melanocytes. Bob Fenner>
Re:
question: behavior of color 12/25/04
Now I'm beginning to understand leucism better, so that I can explain it to
children. Is it correct to say: Through inheritance, leucistic animals have
partial to complete absence of
melanocytes.
<Umm, not absence... this is albinism>
Although there is a reduced number of melanocytes, many leucistic animals can
make some melanin in certain areas, as in their eyes or on their faces.
<Yes>
I would like to credit you in my book. Do you have a degree that I
can add to your name?
<Not necessary, Bob Fenner>
Color Vision in Fishes
Hi gang,
The question just occurred to me as to whether fish in general and Tangs
of various varieties in particular are color blind. Nothing shows in
your data base. So, to your knowledge has anyone tested for this?
Regards,
Charlie H.
>>>Hi Charlie,
Yes, fish are equipped with both rods and cones, and can see color very well.
Some deep water fish can only see in reds and greens - tangs, being surface fish
can detect the entire range.
Jim<<<
Regarding Melanophores!
Hi there Dr. Fenner,
<Just Bob, or Robert if you must>
I emailed you once before about a month ago. In your paper on the Wetwebmedia website, do you know where you found the information on acetylcholine and epinephrine and its effects on the melanophores?
<Would have to search through the posted references... it's been a great while since I reviewed the root information>
Please email me back and help me!
Sincerely,
Nicole
<Are you able to search the literature... at a large (college) library? Bob Fenner>
The Physiology and Behavior of Color in Fishes
Dear Dr. Fenner,
I really enjoyed this piece and would like to give
proper credit to you. Can you please email me the proper citation for this
piece? Thanking you in advance!
Sincerely,
Nicole Hitchen
<Fenner, Bob. 2004. The physiology and behavior of color in fishes. Tropical
Fish Hobbyist Magazine, Sept. 2004.>
The Physiology and Behavior of Color in Fishes
Dear Mr. Fenner,
<Ms. Palmer>
I read your excellent article online at WetWebMedia and found it very informative- I would like to cite your work in a report I am doing on
Zebrafish coloration and give you proper credit, but I am missing some key bits of information. Could you perhaps tell me when you wrote or posted the article, and if it was ever published in a non-internet source (and if so what that source might be)?
<This small survey piece was written and posted just this last year... and did run in Tropical Fish Hobbyist Magazine... about six months back. Am out in HI or I'd look up the citation for you. Perhaps you can just cite WWM as the source with myself as the writer>
I hate to impose but I would really like to give you the proper credit for this piece, it definitely helped me with my paper. Thank you very much for your time.
Sincerely,
Adriana Palmer
Brown University, '05
<Please make it known if I may be of other assistance. Will be back "home" in a week or so. Bob Fenner>
Fish Coloration - Why?
Dear Web Media,
Why do freshwater fish have dull dark backs and shiny silver
bellies? I am home schooled and have not been able to find the answer
to this question.
Thank you. From, Jena Ritchey.
<Well, Jena, there are some very good reasons for this kind of coloration on
fishes. The silvery belly, when seen from below, blends in pretty
well with the light color of the sky as seen from underwater, so predator fish
might miss out on seeing their prey, or so the prey fish might miss out on
seeing the predator sneaking up for a snack. The dark color is harder
to see from above, like from a fish-eating bird looking down, so the dark color
will blend in with the mud, sticks, and such underwater. Not all fish
are colored like this, though; in fact, there are a few fish that are colored
quite the opposite - with dark bellies and light backs - and swim upside
down! Most fish will turn very very pale at night, when it's too dark
to see and their dark color isn't very useful. There are also a lot
of very brightly colored freshwater fishes in nature. Some of these
fishes come from muddy, cloudy waters, and are brilliantly colored so they can
see each other and find mates; in these mucky waters, it's not as important to
have the dark on top/light on bottom colors, because they wouldn't be very
useful; if their predators can't see through the water very well to begin with,
there's no reason to try to blend in, right? Here's a link to a
picture of one of many such brightly colored freshwater fishes: http://www.fishbase.org/Photos/PicturesSummary.cfm?ID=53747&what=species
Hope this sheds some light on things for you! -Sabrina>
Question re behaviour
Dear Crew
<David>
This is probably a most fundamental question from a novice, and yet to date I
have not heard a reasonable (informed!) answer to it:-
Q. Why have certain genera of fish swim evolved to swim with a
tail-down attitude - e.g. Nannobrycon and Thayeria and for that matter why do
some swim with a nose-down attitude - e.g. Abramites? The thought is
that it is linked to feeding habits and yet it would seem to disadvantage such
fish {compared to those that swim 'horizontally'} should they require
to escape rapidly from predators.
Yours sincerely
Brian
<Have not seen much (anything re spatial orientation function) and these
Characoids (or other fishes for that matter) either. Will make some
speculations. The parts of the world (Amazon et al. basins in South America)
where these animals are found are relatively "old" and crowded
relatively... and so as general rules go, there is more competition for food,
space, avoidance of predators... Perhaps the "abnormal" positioning in
the water column confers a benefit in not appearing like a food item? Maybe
there is something to being able to escape up/down instead of ahead, to the
right, left in avoiding "arrow shot" attacks by predators? Maybe
something/s re these "tetras" markings, coloration and change therein
matches with plant life, particle movement, light propagation... in their
environment? Maybe it's time for you and I to make a trip to Brazil's outback?
Bob Fenner> | |
|
