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FMC (FORMALDIHYDE, MACHITE GREEN ,METHALINE BLUE)
FMCS (FORMALDEHYDE ,MALACHITE GREEN  , COPER SULPHATE ) The second equation is correct  or not ? so please informs 
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Copper sulfate is used to eliminate some types of fungi and bacteria
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It is very hard for me to find journals to publish data on the actual status of fish fauna distribution from rivers in Romania. Most of the journals (with IF) reject papers on fish taxonomy and diversity indices. If this happened to you, please name the journal and also if you have published this type of article, please name the journal as well.
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Just try with "Journal of Ichthyology" and "Acta Ichthyologica et Piscatoria".
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I'm looking to detect senescence in Zebrafish embryo and I need a robust control positive (and negative).
Kishi Shuji suggest BHP but exists a better control?
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Does it work
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I need references clarifying the relationship between ostracods and fishes.
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I'm wondering if some of you are aware of existing conversion factors for levels of metallic contamination in fish muscle tissues. In the present work, I'm focusing on metallic contamination, so not currently interested in lipid content of the tissues.
Depending of the contexts, concentrations are expressed relatively to fresh or dry weight. By example, working on muscle sample is more convenient when dried, but concentrations are expressed relatively to wet weigh in European directives, requiring conversion factors.
In most of the paper I read, concentrations are expressed relatively to wet or dry weight, and are then converted using a 5 times conversion ratio. But no information about the actual measurement of the ratio is provided, and I feel this value is largely empirical.
So, is someone aware of the rationale for this value ? Are you aware of papers specifically investigating this point ?
Thanks
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Pierre Cresson , great paper, I downloaded it early today and then came looking for more info on the conversion subject, and found the author himself :D Thank you!
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I read many available articles but none of them concretely wrote this down. Most of them determined a spawning period but I need more specific data to calculate the reproduction rate for DEB-IPM.
Sorry if the answer to this question is very obvious, I am fairly new on this field.
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From scientific references it is found, the reproductive season of Lagocephalus sceleratus was found to extend from late spring to middle summer (reproductive peak recorded in June), this is indicated by Rousou, et al. 2014 (doi: 10.3354/sedao00005).
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This is similar to a previous question I asked. I'm looking for some kind of chemical marker to use for an antibody test to determine where on a fish an unrecognizable sample of tissue came from. All the AMPs, etc. that my research has turned up so far are either pretty species-specific or are also present in the GI tract. Any help would be extremely appreciated.
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المستحضرات الصيدلانية -07 -00265.pdf
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Please provide me with any information about the fish [Nebbash (Barbus schejeh)]. This specie is of the family Cyprinidae, 
With my best regards
Dr M. H. Matllob
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schejch, Luciobarbus Heckel [J. J.] 1843:1055 [65] [Ichthyologie [von Syrien]. In Russegger v. 1 (pt 2); ref. 2066] Syria. Syntypes: NMW 50399 (1), 54520 (2). Spelled schech on p. 1019 [29] and 1098 [108], discrepancy not noted in corrigenda. •Questionably a synonym of Barbus pectoralisHeckel 1843 -- (Coad 1991:14 [ref. 15702], Coad 1995:13 [ref. 23608]). •Synonym of Luciobarbus pectoralis (Heckel 1843) based on generic placement of pectoralis. Current status: Synonym of Luciobarbus pectoralis (Heckel 1843).Cyprinidae: Cyprininae. Habitat: freshwater.
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I have a historical collection of otoliths mounted in both 1,2-dichloroethane and cytoseal which I'd like to remove for detailed shape analysis. I've seen toluene recommended online but can't find any exact methodology. I've also been told xylene may work. Wondering if anyone can give any recommendations?
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Christina, you can use xylene. Best
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I'm wondering if someone is aware of studies investigating the integration time of mercury in fish tissues, mostly muscle. In other words, when a Hg concentration is measured in muscle, is it the result of previous contamination during weeks? months ? years ? I found some papers investigating Hg dynamics in mammals or birds, but I can't find similar studies in fish. This information would be crucial when trying to infer trophic patterns from several biomarkers (eg stable isotopes, fatty acids or contaminants) with different integration time.
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yes, it is, because it is very good for health.
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I have data of catch and catch per unit effort of cuttlefish for 2 years. The data came from artisanal hook and line fishery. Can we simply use the equation which relate CPUE and abundance to estimate fish biomass? How to estimate the catchability coefficient in such case? There are many factors affecting this relationship and sometimes it is difficult to take account of them.
The data I have include catch, effort in time spent fishing (from handheld gps loggers) and the estimated CPUE.
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Nice
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  Particularlythe b12 in spirulina absorbed by the fish and used? I know for humans it is argued not to be, but is it potentially useful in providing fish or zooplankton, with usable b12 supplement. By using live freshly grown spirulina.
Looking at dosing marine zooplankton (copepods) with spirulina and the nutritional affects they have and the ability to pass them on. Furthermore, looking at any particular nutritional benefit soaking food in spirulina may have, etc etc.
Thank you
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The world of micronutrients still has many gaps, and the specific case of vitamin b12 is particularly complex given the clinical importance of its levels, which are low, but also high. In this sense, in complement to the debate question, I want to share with you the following manuscript detailing the aspects associated with high levels of vitamin b12.
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We need to perform a screen for heat shock response activation and I can't find an european source for a simple Tg(Hsp70:GFP) line. The source should preferably be in the EU, because we've had unpleasant experiences with border delays after shipping some planarian lines from the US and I'm not sure embryos would survive.
EZRC has Tg(Hsp70:EGFP-HRAS), I suppose we could use those, but wouldn't that make the methodology seem too messy?
Regards,
Vlad.
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In fact, I am also looking for a Tg hsp70-egfp ZF line source. Strangely enough, EZRC in Karlsruhe suggests only 2 Tg lines for "hsp" query. Tg(hsp70l:mCherry,Cre-ERT2) and Tg(hsp70l:mCherry,Cre-ERT2)tud105(AB/TL). Not the one, Vlad mentions - Tg(Hsp70:EGFP-HRAS). Is there something wrong with their search engine or with my query, I wonder?
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(Ivlev, V.S. 1961)
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Hello guys,
Do you know what package in R I can use to calculate the Vanderploeg and Scavia's Electivity Index?
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I would like to know exactly what happens in the cell cycle?
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Marine Pollution Bulletin. Vol. 91, Issue 2, 28 February 2015, Pages 518-523
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I found it in seagrass beds of Kepulauan Seribu (Seribu Island), Indonesia.
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For identification we would need more detailed photographs of the fins, especially pelvic fins, dorsal and caudal fins. Might be a gobiid or microdesmid; probably not a clupeiform, and certainly no engraulid.
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I have received project reports Lazar et al. 2017 and Pabi et al. 2014
evaluating recent stocks of small pelagics (Sardinella aurita, S. maderensis, Engraulis encrasicaulis, Scomber colias) off Ghana, but I search published information on long-term seasonal presence and reproductive biology, as to correctly interprete dolphin (predator) presence. Anyone can suggest/provide papers? Thanks.
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Kindly any body help  me for identification of this species
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Respected Sir,
I think it comes under antennaridae,mostly the genus may be antennarus spp
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Dear Scholars, could you help me finding the total P and N contents percentage in the produced farmed Arctic char body (Salvelinus alpinus), please?
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Thank you both for your contribution. I look for quantities already set by others and not conduct my own lab work, as currently don't have access to any. I looked in the suggested papers and couldn't find what I am looking. To be more precise, I look for the Arctic char quantities of N and P inside their body. For instance, for Rainbow trout: In 26%dry matter, there is 6.8%N and 1.2%P.
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Using fish as an example, if you have total length and age and compute a growth rate by dividing total length by age would this "age-specific" growth rate, "absolute" growth rate, etc.?
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Sorry to say but the formula is not correct; it has to be: SGR = (ln(final weight in grams) - ln(initial weight in grams)) x100 / t (in days).
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Normally freshwater fish meristic character of fin ray counts example dorsal fin or caudal fin rays count variability of same within species it possible or not if possible why it occurred. 
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Some fin counting formula are there and it contains the range also. If exceed the range means exceptional...the reason mostly genetic-environmental variation. Formula for fins of fishes-
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Dear all,
we have some fish larva collection from Caspian sea drainage. In some cases I need to help, I will be glad if I see a photo of Atherina boyeri eggs.
All the best,
Mahnaz
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Hi Mahnaz,
No, I'm sorry, it interests me too!
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What are the new methods for measuring body length at first maturity for fish populations?
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We collected many fish eggs in a coral reef off the coast of Vietnam. Is that Scarus genus?
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Hi.
Do you have some publication about this eggs?
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I am contemplating if we can utilize fish otolith as a marker for fish species, specially among the gut remnants among piscivirous fish within an isolated lake ecosystem.
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Of course. The morphology is described in many otolith atlas and papers, although depending on family it could be more complicated or not for a novel. I recommend you the contour analysis to improve the results and to automatise the process. In AFORO yo have an automatic classification system based on 1716 species and 234 families
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I am planing to assay innate immune response in common carp larvae (30 days post-fertilization).
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The added paper by A.E. Ellis on lysozyme assays in fish could be helpful. Best wishes, Willem Van Muiswinkel
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Dose anybody have some photos from below crab species? I could not find. 
Potamon gedrosianum
Potamon magnum
Potamon mesopotamicum
Potamon ruttneri 
Potamon strouhali
Potamon transcaspicum 
 Potamon bilobatum 
Potamon ibericum 
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You can have a photo of Potamon gedrosianum in this paper of mine
Records of non marine brachyuran crab species of Pakistan including note on their ecology & description of juveniles of Sartoriana blanfordi
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The correlation between fish (freshwater) bioaccumulation to damage fish organs (gills, kidney, liver, mussels) it seen biopsy? if possible means why it occurred what is function happened in biological activity... can explained in detail to discussion of biological actions.
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Yes it is true combined action of toxicants may reduce the toxic effect of induvidual chemical effect on organans/tissues.
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classical taxonomy...
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If you are asking how to construct a phylogenetic tree using fish morphology and meristic characters, then you are not talking about "classical taxonomy".
You have already received several comprehensive and helpful suggestions and advise from four colleagues. You have then been informed about different methods that you may use. However, all of those programs work with a matrix that you will have to build by yourself and this is a most difficult part because, and depending on the list of characters that you have and of their coding, the selected outgroup(s) to polarize characters, and also the composition of the selected ingroup, the results may be different.  
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I am designing a study examining burst (maximum short period fast-start swimming) swimming in a range of fish species in a swim chamber. Many of the older papers used electric stimulus to provoke burst swimming. To me this looks like the most consistent and therefore repeatable method but I'm running into animal ethics difficulties.
Some of the newer articles use other physical stimuli (e.g. tapping the chamber, squirting with a pipette etc) to provoke burst swimming but I worry about the repeatability of these methods. Other papers purport to provoke burst swimming by rapidly increasing velocity but this must involve some level of fatigue and depends very much on the behavioral response of the species in question. 
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HI, you might look into literature on the startle response in fishes. I seem to recall several studies that used cameras and a background grid system to document the behavior in larval fishes. I don't think the goal was to measure speed, more about behavior and reaction time, but the methods might give you some ideas.
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We have measured whole-body copper content in tilapia larvae when their yolk sac were almost disappeared (fry). At that time, there was no external feeding. We found that a significant bioaccumulation of Cu while the Cu concentration in water was not detectable (<0.001 ppb). We therefore supposed that the origin of Cu might be related to its concentration in yolk.
Please let me know if you have any similar experiences.
Many thanks, 
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This reference has been published on the composition of the eggs of three species in captivity (including copper) . Regards
Devauchelle, N., Brichon, G., Lamour, F., & Stephan, G. (1982, January). Biochemical composition of ovules and fecund eggs of sea-bass (Dicentrarchus labrax), sole,(Solea vulgaris) and turbot (Scophthalmus). In International Symposium on Reproductive Physiology of Fish Wageningen, the Netherlands 2-6 August 1982. (online)
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I want to compare the ploidy of the cells with a reference
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I've find DNA calibrator in Beckman coulter. It's OK for ploidy study
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I saw the formula above the question, but I can't understand in detail, any one can explain in detail above the formula along with how to analysis with statistical software example using EXCEL or any other software is there pls explain...
Thanking you...
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Take the length in cm and weight in gm. Find the log values of both.Draw a scatter diagram and add the trend line . Find the extreme outliers and remove it. Then insert the trend line and get the regression equation. Simple excel you can do this
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I have a little statistical problem to resolve. Actually I have data with distances between a target fish and three prey (quantitative dependent variable) in function of time (quantitative  input also) and I found that it is called a time serie.
My question is how to compare these three time series ? Graphically, when target fish is attracted by one of the prey, the distance between them decrease dramatically while distance with the two other preys is constant or increase slightly. How can I compare these thresse series statistically and how can I determinate statistically the time at which fish is attracted by one of the three preys ?
Thank you for answering me
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Dear Imen,
I think you should first determine what your H0 hypothesis is. As a reminder, the H0 hypothesis is the hypothesis where you consider that two or more statistical datasets are not different from each other. These datasets should be built so as to check whether a scientific assumption is most probably true or not. It is important to precisely define this scientific assumption and be able able to write it down, so that it is a yes/no assumption. Then, you can choose the appropriate statistical test to check if it is probably true or not. There is no statistical test which will emits the scientific assumption and conclusion by itself.
In your case, it is unclear what the scientific assumption is and what these datasets are. From what you explained, I could propose many scientific assumptions to look for. But I think you already have your own idea. So, as Andreas said,  I think it looks like you're trying something over-sophisticated because you did not provide the scientific assumption and what the corresponding datasets exactly are.
If you're looking for discussions  about ideas of scientific assumptions to be tested, this is another story and I would be glad to discuss it, although I'm no expert at all in fish behaviour. So, you may not learn much from me and I would probably learn much from you.
Best regards,
Neil
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For human health we use a number of general and specific tests that help understand the condition of people.  Have any such tests been done and tested for fish?
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Condition factor and indices of energetics such as hepatosomatic index are good estimates of fish health in wild. But they work only if compared to a control group 
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Basically is there any way you can think of to ascertain that a fish caught from the wild has been feeding on the slime coats of other fishes opportunistically without having observed its behaviour? Is it even possible? I suppose an antibody test of some sort might work but that would be expensive and time-consuming to create. This is an idea I'm hoping to incorporate into my potential future master's thesis.
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hi
can by QPCR  IT good method 
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Does anyone know where(online) I can get a complete fish cell culture protocol, specifically for salmon head kidney cell?
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Hello Ernesto, please follow the link above. You may also follow the instruction from the providers (sigma) of the SHK-1 cells ( http://www.sigmaaldrich.com/catalog/product/sigma/97111106?lang=en&region=NO )
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Can any help me if is it possible to measure DPP-4 in fish tissue?
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What is DPP-4?
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Is there any type of circadian clock rhythmic expression happens due to different colors of light? Or different intensity of the light can affects? 
Kindly give me any suggestion.
Thanks 
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I'm looking to conduct an experiment examining how the dopaminergic system may influence the decision to strike or avoid a fishing lure in sportfish.  I'm looking to use D1/D2 receptor agonists (SKF-38393 hydrochloride/Quinperole hydrochloride) and antagonists (R-(+)-SCH hydrochloride/Eticlopride hydrochloride) to manipulate the DA systems in these fish.  My question is a methodological one.  After mixing the solutions and immersing a fish, can I preserve the solutions for subsequent re-use, even over a period of a few days of trials?  Or, do I need to mix a fresh solution for each fish?
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We are working on the agonist SCH for reproduction. When we asked if dopamine and SCH are stables in time, the manufacturer told us that it is not stable beyond 24 hours.
So you need to prepare fresh solution daily.
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Hi all, 
    For estimating Lm, different researchers uses different methodologies. Some uses the lowest recorded mature fish as Lm. Some researchers estimated it by eye observation of visible egg. Some estimates from the first peak og GSI. Some uses cumulative percentage of all samples of fully matured egg (Stage v and above) to estimate Lm. But is there any method to calculate Lm based on histological  stages (i-vii) and maturity stages i.e., cumulative percentage of samples over certain maturity stages  (stages i-vii/viii) ?
waiting for your innovative ideas...... 
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To my knowledge the most common method is still to analyze maturity ogives i..e. plot the proportion of mature individuals (or separate females and males) by length class and analyze the resulting curve, which should be logistic. Many people then detemrine the point  at which 50% of the observed individuals within a length class are mature (LM50), but you can also use any other threshold depending on what you would like to do with your results.
Anyhow you need length and maturity data (i.e. in stages) for this.
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Sex determination, loach, juveniles
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 good answer Gloria Arratia
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Extraction protocol for high-quality fish DNA from tissue,fin. 
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Thankyou All for supportive responses.
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Hi all, 
I have collected this specimen from Mumbai coast of India. But I have a confusion with the identification of this species. Please share your experience for identification of this species.
Regards,
Rupam Samanta
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The image does not show all the characters necessary for identification, but judging from the striped colour pattern and the shape of the esca this is probably Antennarius hispidus (Bloch & Schneider 1801) (family ANTENNARIIDAE). This species is known from India, but it is also widespread in the Indo-West Pacific (Red Sea and East Africa east to Tonga).
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Fish will engage in normal breeding behavior but will not release eggs. 
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when u setup fish breeding the male fish dont movie in large place so you will block small area. 
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The encephalization quotient (QE) are calculated for each species using the allometric equation describing the brain mass to body mass relationship (modified from Lisney & Collin, 2006). The brain metrics can considers "brain areas (the olfactory bulbs, telencephalon, optic tectum, corpus cerebellum and the octavolateralis area)" - Lisney & Collin, 2006) -  or the total brain or the spinal chord. Inasmatch QE is defended and criticized by different academicists, even in mammals researches, can we use QE to analyses freshwater fish communities (using the community ecology framework)?
Reference:
Lisney, T. J. and Collin, S. P. (2006), Brain morphology in large pelagic fishes: a comparison between sharks and teleosts. Journal of Fish Biology, 68: 532–554. doi:10.1111/j.0022-1112.2006.00940.x
Supplemenary reference:
Jerison, H. J. (1977), THE THEORY OF ENCEPHALIZATION. Annals of the New York Academy of Sciences, 299: 146–160. doi:10.1111/j.1749-6632.1977.tb41903.x
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Interesting question. Reminds me of (Huber and Rylander 1992) paper (citation below) where brain morphology (e.g., ofactory and optic lobe size) and turbidity preference was measured for some minnows. Hope this helps!
Huber, Robert, and Michael K. Rylander. "Brain morphology and turbidity preference in Notropis and related genera (Cyprinidae, Teleostei)." Environmental biology of European cyprinids. Springer Netherlands, 1992. 153-166.
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Hi All,
I'm interested in opinions of experts on the age of this sample Alaska plaice (Pleuronectes quadrituberculatus) from south-western part of the Bering sea. My preliminary estimate is 13 years.
Thank you in advance.
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Lots of checks! I was going to go with 11 years old with your first image-- great to have Beth weigh in.  
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Dear Friends
I am working on the osteology of the fish species John Dor, Zeus faber from different countries.
I appreciate very much the assistant of any friend who can get me an x-ray fro 3 specimens of the fish species Zeus faber from the waters of the following countries:
Brazil, Uruguay, Argentina, Chile, Peru, Ecuador, Namibia, Congo, New Caledonia, Fiji, and Papua New Guinea
Laith A. Jawad
Auckland
New Zealand
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Sorry Dear jawed ...so maybe usful to other researchers 
Regards 
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My male Brown banded bamboo shark has now got a scattering of very small black spots round its head just forward of the gill slits that I've never seen before and he was slightly more reluctant to feed.
I am a little concerned and was wondering if there were any connections and that the black spots were some form of parasite or illness as the moray I keep in the same tank was recently very pale and is still refusing to feed despite his colour mostly returning.
I would get a picture of the spots but unfortunately. my bamboo sharks are far from photogenic and won't stay still long enough for me to get anything more than a very blurred mess
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Ok thanks again Fahmi
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I'm relating  the occurrence of micr plastic in the gut of fish species to its total length to see if there's a relation. I feel that the gape size in relation to the micro plastic would be a better comparison to make and therefore, using the data of total length and occurrence of micro plastic, is it possible to obtain a gape size? 
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You can find 61 species' TL-gape relationships in my publication, as well as general ones based on species' functional trophic groups:
KARACHLE PK & STERGIOU KI. 2011. Mouth allometry and feeding habits in fishes. – Acta Ichthyologica et Piscatoria, 41 (4): 255-275. (attached)
To my knowledge there is no such general relationship .
Regards
Voula
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I am wondering if anybody know if a NeuN stain will work on fish, especially the California killifish (fundulus parvipinnis)?
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Dear Siri,
I suggest that you try first with one brain and test the results. I am suggesting this because I have not had the best results when doing preparations for nervous system  and depending on the results I had to do several modifications to the process that in one specimen gave nice results, but not in others. I am not able to explain this because some of our colleagues have very nice slides. Thus, try first with one brain and evaluate the results.
With my best wishes.
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Both steelhead and rainbow trout are the same species Oncorhynchus mykiss.  What I thought is Steelhead trout migrate from the ocean up rivers to spawn like salmon, and live the majority of their life in the Ocean, at high salinity. While rainbow trout live their entire life cycle in fresh water.  Why is it then that freshwater RAS system produce Steelhead, as well as Fresh water lake aquaculture operations and Wild lake fisheries?  
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You've already hit the fundamental distinction.  Anadromous O. mykiss are steelhead, and non-anadromous O. mykiss are rainbow trout.  In our research (Hodge et al. 2016), we found that steelhead mothers could give rise to rainbow trout progeny, and rainbow trout mothers could give rise to steelhead progeny (might also see Zimmerman and Reeves 2000 and Zimmerman and Reeves 2002).  That said, progeny of anadromous mothers were more likely to become steelhead than trout.  We also found some patterns with respect to freshwater growth rates and anadromy/nonanadromy.  In general, rainbow trout grew faster in freshwater than juvenile steelhead (but there was a notable exception).
Overall, the "fate" of O. mykiss offspring probably reflects an interaction of genetic and environmental factors.  That said, I wouldn't call an individual a steelhead until it entered the ocean, regardless of its maternal/genetic origin.
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These species(image) belong to family Clupeidae. I can't identify them well. Can anyone help me? please 
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Please say more about sampling ground.
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I got this image of a ray for ID. The disc is wedge-shaped, this would be typical for guitarfishes. The TL of this specimen is about 20 cm. I have no other images! I never saw a ray with such a coloration.
Place of finding: Harnay Murud sandy beach, India, Arabaian Sea
Thanks for your ideas and comments!
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Hi Juergen, I can't comment on the ID of this ray but it appears to be a melanistic or pseudomelanistic individual. It's pretty common in elasmobranchs. I've seen it in several Squalus and Mustelus lenticulatus. The magpie banjo ray (name eludes me right now) described from South Australia was recently shown to be a melanistic morph of the southern banjo ray.
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I'm trying to determine a quick and easy way to simply compare the quantity of sialoglycoproteins in fish seminal fluid between two groups, so I don't necessarily need to quantify proteins as accurately as would be accomplished with mass spec or something similar. I would be able to access some optical instruments if necessary (e.g. spectrophotometer, plate reader, etc.). Previously stained these proteins with alcian blue, but looking for a way to easily quantify for comparison.
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Hi everyone, thanks for your answers! The linked article was very informative. I think my plan will be to use a modified Bradford assay, but stain with both coomassie blue for total proteins and alcian blue for sialoglycans, and use a standard like purified fetuin to quantify the strained sialoglycans. I might have trouble reading the alcian blue-stained samples via spectrophotometry because the stain molecules aggregate, so I've been told to use a solvent like DMSO or ethanol. Will also need to troubleshoot the range of protein standard to capture the concentrations found in my samples, but also be sensitive enough for sample variation.
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I am working on fish bacteriology band presently facing problems in analysis of SEM photographs
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There is a vast literature on this subject, including several textbooks. Try searching on BKD, bacterial kidney disease, or just use appropriate search terms in google scholar. 
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The degree of toxicity of tetraodontoxin TTX in Tetraodontiform fishes varies by species, and also according to geographic area and season. I want to know the toxicity of the species Ephippion guttifer. 
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Gracias Luís, si que me interesa
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best homogenization buffer for fish liver?
how to prepare?
suitable for most antioxidant enzymes?
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That depends on a couple of questions:
Are you interested in extracellular or intracellular proteins. For extracellular use Na+; for intracellular use K+. The physiological pH inside cells is somewhat lower (6.8) than that of the extracellular fluid (7.4).
If you want to use ion exchange chromatography, make sure that your buffer ion doesn't bind to the resin. I.e., for cation exchange use an anionic buffer (like HEPES), for anion exchange a cationic (e.g., Tris).
Osmolytes (glycerol, sugar, mannitol) may be useful to adjust the osmotic pressure, but not all proteins require them.
You may need some ions (Ca, Mg) or small molecules (substrates) to stabilise your protein. Don't forget protease inhibitors!
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We have a collection of around 70 species specimens from 20 families; all from Vembanad Lake, Kerala, India.  We would like to know what all are the effective long term preservation techniques, either using Isopropyl alcohol or something else; except Ethanol (due to availability issues in Kerala). We would like to display these wet specimens too, since there are no collections of this kind available in the vicinity.
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Dear Anu, We also changed our fish collection from formalin to alcohol some years ago. If the fish were fixed in formalin first, there no problem with conservation in alcohol. Use glass jar only as plastic one deteriorate after years. Just make sure to use very good lid on top of your jar to prevent as much as possible evaporation. It will occur anyway so you need to have a well ventilated  room for health and safety. A special care should also be given to fire risk analysis and prevention. In case you do not want to put your specimens anymore in formalin and you want to fix them directly in alcohol make sure you have enough volume because alcohol is not very for fixing tissues. You will need a large amount of alcohol compare to the volume needed with formalin. I hope this can help you. 
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The recent revision of Pristis synonymized several former species into Pristis pristis (Faria et al 2013). However the former northern limit of this species in the Western Atlantic is not clear, specially since all sawfish species have suffered dramatic range collapses globally and are in the brink of extinction. 
Does anyone know what is the most northern confirmed occurrence of P. pristis in the Gulf of Mexico? Unfortunately all of the museum specimens seen by Faria et al. (2013) from the Gulf of Mexico had NO specific locality!...
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Ramon:
May kindly have a look for confirmed northern limit of Pristis pristis in western Atlantic:
Best
Syed
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comet assay
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Dear Aasma Noureen
you can assess the tail movement, head length and tail length of comet assay by micrometer (µm) using  the comet score -image analysis Software (TriTek Corp., Sumerduck, VA)  
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I search into Articles and there is no detailed information for age at maturity calculation protocols, and I didn't calculate GSI because my sampling wasn't monthly basis. So Is that make any trouble in that calculation?
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Hi Milad,
you do not have to calculate GSI to estimate age at maturity. You need just to know the age of every fish you sampled (in months or in years, depending on life expectancy) and physiological status (adult, mature vs immature). Then you need to calculate a sigmoid curve describing changes in percentage of adults in the sample with age (beginning from zero in juveniles, eventually it will be 100% when all fish become adults). The age when this curve crosses 50% is age at maturity.
Best regards,
Vlad
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can anyone identify this gobiid, collected from Andaman Islands? thank you
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I agree with Istigobius diadema. Great to have a goby specialist around!
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Good afternoon,
I have two main questions. I am working on the amplification of several mitochondrial and ribosomal markers for fish DNA. As I want to sequence afterwards, I was looking for a PCR enzyme with a high fidelity. I saw the Platinium SuperFi (Invitrogen) and got a free sample to test my primers (3 mitochondrial, 1 ribosomal). I tested these 4 markers and only one worked (clear band on the gel after electrophoresis).
These primers are coming from the literature and have been used on fish previously so I am wondering if the problem comes from the PCR conditions. Indeed, Tm given by the calculator specific of this enzyme are much higher (sometimes 10° difference) than the Tm found in other papers. I called the technical support related to this and they advised me to only test the Tm given by the calculator and eventually 2 degrees less. One of my colleagues just advised me to go for 5°C less and that it might be the reason why I didn't see anything for 3 markers (Tm too high). Has anyone got experience with this enzyme and knows if that could be the problem ?
Second question, it seems that this enzyme is a bit too much for what I want to do after with the PCR products. I am currently looking for PCR enzymes less specific, but still good enough to have good results (error rate low enough).  I saw the HotStar HiFidelity Polymerase Kit (QIAGEN) and the Phusion Hot Start II High fidelity (ThermoFisher). Has anyone any other suggestions ? (PCR product sizes : between 500 and 800 bp).
I would be very grateful if someone can help me or give me an advice.
Thanks !
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Dear Lola
As far as I know, there is (neither theoretical or practical ) no PCR enzyme which can carry out all the amplification you desire. You have to try a few enzymes to get the required results.
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I wish to examine laminin in fish fillets connective tissue, but I am not sure which type(s) would be most prudent to start with. Has anybody experience or knowledge about distribution of the various laminin types?
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this is the same specimen with the second photo taken 11 days after the first. It was kept in an aquarium during that period. TL was approximately 4-5cm. It was found in a small harbour for fishing boats (Faliraki, Rhodes), caught with a hand net.
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Hello,
I would say as Antonio: Diplodus puntazzo. On of the helpfull details is the shape of the dark mark on the caudal peduncle: in D. sargus, it does not touch the bottom edge of the peduncle, while for D. puntazzo it does (see attached file).
All the best,
Adrien
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With the continuing growth of the aquaculture industry, more attention to fish welfare must be given as it has significant impacts on health and resistance to diseases.
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Dear Majid,
 The information so helpful, Thanks very much.
Regards
KS Al-Niaeem
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I need your help to identifying this species ? 
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Fish from the family Callionymidae, probably Callionymus filamentosus
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Can any friend help identifying this Gobiid species?
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Dear friends thanks to you all.
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Which method  is perfect for identification of fishes.
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If you assume that:
  1.  all possible identifications have sequenced examples;
  2. You can trust the a priori identifications of the researchers depositing all of those reference sequences;
  3. Unsampled cryptic intraspecific diversity does not exist within your species that might confound your result, or is not discriminated by your marker of choice;
  4. You can trust an arbitrary threshold to distinguish between "match" (i.e. same species) vs. "not a match" (i.e. not the same species), AND can apply this same criterion ubiquitously (e.g. ignoring rate heterogeneity across lineages);
  5. There is no mitonuclear disequilibrium (hybrid individual may have mtDNA "barcode" of species A, with nuclear genome of species B), or otherwise discordance between your marker (=single locus ancestry) and the rest of the genome;
  6. etc...
No it isn't perfect... But it does provide a hypothesis when species ID is not known a priori...
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Dear colleagues
I am compiling a catalogue of fish vertebrae and scales from the most important fishes off Peru (in terms of abundance). One of my colleagues gave me these fishes collected with multi nets (for zooplankton) off Peru and I have problems with the identification of some fishes.
My guess is:
m093_mn05_n1 sample2" correspond to Triphoturus oculeum;
m093_mn07_n2 sample1 correspond to Lampanyctus parvicauda
m093_mn07_n2 sample2 correspond to juvenile individuals of Triphoturus oculeum 
m093_mn05_n1 1of4 correspond to Diogenichthys laternatus.
Here are some details of the stations:
m093_mn05_n1: ±12 °S, 1000 to 600 meters depth
m093_mn07_n2: ±14 °S; 600 to 400 meters depth
Hope anybody could help!
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Going from top to bottom: 1st is a Cyclothone, may be C. acclinidens but cannot see the teeth or gill cavity; next is Triphoturus mexicanus; the tray contains various Cyclothone spp., but the one on the bottom may be a Platytroctidae (at this resolution, cannot see if there's a tube-shoulder organ); and the last is Diogenichthys laternatus.
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I need some paper about the computation and interpretation of biological statistic of fish population.
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Computation and Interpretation of Biological Statistics of Fish Populations
Computation and Interpretation of Biological Statistics of Fish Populations
Item# 978-1932846-232 (Paperback; 400 pages)
Bulletin 191 of the Fisheries Research Board of Canada
by W. E. Ricker
Computation and Interpretation of Biological Statistics of Fish Populations, first published in 1975, is William Edwin Ricker’s third Bulletin that deals with the general field of biological statistics of fish populations. It is a compilation of the more important procedures used to estimate abundance, age composition, rate of growth, and mortality rates in fish populations, with working examples of all the computations.
Computation and Interpretation of Biological Statistics of Fish Populations is one of the most highly cited scientific references in the field of fisheries.
William Edwin (Bill) Ricker (1908 – 2001) is an important founder of fisheries science. He is best known for the Ricker model which can be used to predict the number of fish that will be present in a fishery. In fisheries, he researched issues centered on Canadian fisheries and how to manage them.
In 1950 Ricker became editor of the Journal of the Fisheries Research Board, and during his twelve year tenure developed this into perhaps the most influential fisheries science journal in the world.
Preface
Chapter 1. Introduction
The problems; Definitions, usages, and glossary; Symbols; Numerical representation of mortality; Recruitment, stock, and catch in numbers; Growth and yield in weight; Fishing effort and catch per unit of effort; Maximum sustainable yield; Sampling error
Chapter 2. Estimation of Survival Rate and Mortality Rate from Age Composition
Survival estimated from the abundance of successive age-groups; Simple catch curves; Non-uniform recruitment (Use of catch per unit effort for estimating survival); Recruitment to the fishery over several ages; Change in mortality rate with age; Change in mortality rate with time; Catch curves based on length frequencies; Catch curves for anadromous fishes; Stratified sampling for age composition; Effects of inaccurate age determinations on estimates of survival rate; Selectivity of fishing gear
Chapter 3. Vital Statistics from Marking; Single Season Experiments
General principles of population estimation by marking methods; Petersen method (single census); Effect of recruitment; Effects of marking and tagging; Loss of marks or tags; Non-random distribution of marks and of fishing effort; Unequal vulnerability of fish of different sizes; Incomplete checking of marks; Multiple censuses; Systematic errors in multiple censuses; Estimation of natural losses and additions to the stock; Schaefer method of stratified populations; Contributions of separate stocks to a common fishery
Chapter 4. Population Statistics from Marking Experiments Extending Through Two or More Time Intervals, with Constant Survival Rate
Marking done prior to the first fishing season; Marking done throughout the first fishing season with recoveries in at least two seasons; Systematic errors (Types A and B); Systematic Errors (Type C); Graphical methods of estimating effectiveness of fishing
Chapter 5. Population Statistics from Marking Experiments Extending Through Two or More Time Intervals, with Variable Survival Rate
Population and survival rate when marking is done at the start of fishing in two consecutive years—Ricker’s method; Survival rate when marking is done throughout the year; Population, survival, and recruitment from a triple-catch experiment—Bailey’s method; Population, survival, and recruitment from a 4-catch or longer experiment—Seber-Jolly method; Survival estimated from marking in one season, in conjunction with fishing effort data; Marking done throughout the year—Natural mortality varies with age; Rate of fishing during years of recruitment; Estimation of percentage of the younger age-groups present on the fishing grounds
Chapter 6. Estimation of Survival and Rate of Fishing from the Relation of Fishing Success to Catch or Effort
Principles of fishing-success methods; Population estimates from the relation of fishing success to catch already taken—Leslie’s method; Population estimates from the relation of fishing success to cumulative fishing effort—DeLury’s method; Systematic errors in fishing-success methods; Use of fishing-success methods with marked populations; Fishing-success methods when more than one kind of fishing effort is used, or when there are data for only a part of the effort
Chapter 7. Estimation of Survival and Rate of Fishing from Catch and Fishing Effort in Successive Years
Direct comparison of catch and fishing effort; Rate of exploitation estimated by equalization of fishing effort—Sette’s method; Rate of fishing and natural mortality from comparison of survival rates at two levels of fishing effort—Silliman’s method; Rate of fishing and natural mortality from catch and effort statistics, when effort varies continuously—Beverton and Holt’s method; Rates of fishing and natural mortality from catch and effort data—Paloheimo’s method; Rate of fishing from catch and effort data when natural mortality rate is known or postulated; Estimates of catchability made with incomplete information on catch and effort; Rate of fishing from catch and effort data, recruitment, and natural mortality rate—Allen’s method
Chapter 8. Estimation of Stock and Mortality from Statistics of the Catch and Its Qualitative Composition
Derzhavin’s biostatistical method of population analysis; Utilized stock and biostatistical rate of exploitation when age composition varies—Boiko’s method; Estimation of actual population from utilized population and recovery of marked fish—Fraser’s method; Combination of utilized stock estimates with the Beverton-Holt iterative procedure; Rates of natural and fishing mortality, given constant recruitment and natural mortality and two or more levels of stable catch—Tester-Gulland method; Sequential computation of rate of fishing and stock size (cohort analysis); Sequential computations when fishing precedes natural mortality; Population estimates by “change of composition” or “dichotomy” methods; Estimate of survival from differences between the sexes in age at maturity—Murphy’s method
Chapter 9. Growth in Length and in Weight
Estimation of age and rate of growth; Types of growth rates; Weight-length relationships; Effects of size-selective mortality; Computation of mean growth rates; Mathematical description of increase in length—the Brody-Bertalanffy procedure; Use of a Walford line for estimating growth of older fish; Walford lines and Brody-Bertalanffy equations from the growth of marked fish—Manzer and Taylor’s method; Increase in weight and age; Gompertz growth curve; Growth compensation; Estimation of survival rate from the average size of fish caught
Chapter 10. Computation of Yield from a Given Recruitment
General conditions; Estimation of equilibrium yield—method of Thompson and Bell; Estimation of equilibrium yield—Ricker’s method; Estimation of equilibrium yield—Baranov’s method; Estimation of equilibrium yield—method of Beverton and Holt; Estimation of equilibrium yield—Jones’ modification of the Beverton-Holt method; Approximations in Beverton-Holt yield computations; Changes in age structure and biomass resulting from fishing; Temporary effects of a change in the rate of fishing; Allen’s method of calculating best minimum size
Chapter 11. Recruitment and Stock-recruitment Relationships
Types of recruitment; Estimation of recruitment—biostatistical method; Estimation of recruitment—Allen’s method; Effects of environment upon recruitment; The relation between stock and recruitment; Ricker recruitment curves; Beverton-Holt recruitment curves; Other recruitment curves; Compensatory and density-independent mortality rates
Chapter 12. Recruitment and the Fishery
Relation of equilibrium yield to rate of fishing, for different recruitment curves (equilibrium situations); Interaction of a recruitment curve with a changing rate of fishing; Fisheries attacking mixtures of stocks having different recruitment potentials; Combinations of recruitment and yield-per-recruit analyses
Chapter 13. Direct Estimation of the Relation of Equilibrium Yield to Size of Stock and Rate of Fishing
General aspects of additions-and-removals methods; Parabolic surplus production curve and logistic growth curve—Graham’s method; Relation of equilibrium yield to fishing effort; Relation of surplus production to size of stock, using the yearly increase or decrease of stock—method of Schaefer (1954); Computation of a parabolic yield curve when catchability (q) is not known independently—method of Schaefer (1957); Generalized production model—method of Pella and Tomlinson; Relation of surplus production to stock size of the years that produced the current recruitment—Ricker’s method; Relation of catch per unit effort to the fishing effort of years immediately past—Gulland’s method
Appendix I. Table of Exponential Functions and Derivatives
Appendix II. Confidence Limits for Variables (x) Distributed in a Poisson Frequency Distribution, for Confidence Coefficients (= 1 - P) of 0.95 and 0.99
Appendix III. Characteristics and Relationships for Two Types of Recruitment Curve
Appendix IV. Regression Lines
References
Index
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The specimen was caught in the area of Lastovo island in Croatia at a depth of 70 meters. It was an recently spawned female, 47 cm long. It has radically different coloration than other specimens of the same species which are mostly brown. We suspect this is a case of xanthochromism, but any other theory is more than welcome. It would be very interesting to know of other experiences with this or similar type of coloration in this species. Additionaly, patches of brown coloration were still visible on the head of the specimen.
Thank you!