Science topic

Marine Ecology - Science topic

Interested in Marine Ecological research like demersal living resources and their community structrure. Primary productivity, Food chain, etc
Questions related to Marine Ecology
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The only way for companies that carry out ecological activities to be implemented in the future is to surpass polluting companies in their field, being more competitive than them, through technologies such as Blockchain and innovation in production processes. Discover how carbon credits are going to help green companies be profitable and how prosumers are going to play a leading role in that process
Can cryptocurrencies be used to make ecology profitable?
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Man himself is an organism within the environment. He is influenced by the physical features of the environment. With the establishment of specialized disciplines of ecology, the importance of ecology to such fields as agriculture, forestry, limnology, fisheries and aquaculture management, pest management, wildlife conservation etc. became apparent. By applying certain ecological principles to fields such as agriculture, forestry, horticulture, fishery biology and pest control, he has received tremendous economic gains. Though man has controlled his environment successfully to meet his needs, but indiscriminate control in some instances through use of different chemicals or pesticides, release of carbon dioxide gas in the air, release of radioactive debris, discarded chemicals and industrial wastes into rivers result in aquatic and water pollution which may have a short or long time ecological effect. Rapid growth of urbanization and fast rate of multiplication of human population and consequently their needs, have resulted in a threat to ecology. Hence, to gain profit from ecology, all these negative aspects should be stopped.
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This can be detailed or anecdotal, quantitative or qualitative. Over the course of years or decades. Anything that reports changes in the size of the canopy forming species.
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What are the scientifically confirmed examples of changes in marine and ocean ecosystems caused by the probably faster global warming process and the increasing pollution of sea water toxic waste and assessments?
Please reply
I invite you to the discussion
Thank you very much
Best wishes
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The so-called "global warming" Why not to study the "Global Cooling" phenomena which will inevitably replace the "global warming" is a temporary phenomenon which we observe at present (?).
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We will be conducting a survey for marine birds and mammals this summer and we were wondering if anyone has experience with using voice to text software to record marine bird/mammal observations during at-sea surveys? We are planning to use dLog survey software (R.G. Ford Consulting), or equivalent, which has a user interface with data entered into discrete boxes. Each observation is given a time and lat/long location once the user hits the RETURN key to log the observation. Given limited space for computer/handheld GPS/etc. near the observation platform, however, we would be interested in hearing if other researchers have been able to successfully use a voice to text software to record observational data. Such a system would help overcome the limited space issue.
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Here's a descendant of dlog --
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It is experimentally proved that turf algae in combination with sediment prevents the settlement of coral larvae. My field observations are contradictory to it. I observed lot of new recruits on hard substrate which has been covered with turf algae and sediment. Is there any other factor which could aid the settlement of coral larvae on a turf algal substrate?
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We are identifying a large numbers of detrital mineral samples from the marine sediments. We have excluded staining method because it takes a lot of time.
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For microscopy, we should not forget that determination of refractive indices (RI) can be quite useful and fairly quick. For example, if you use a liquid of RI 1.527, Or grains would have lower RI in any orientation, whereas Qtz and Pl grains would have highern RIs. Carbontes should not pose any problem because of their high interference colour. But the procedure is tedious and gone unpopular.
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UPD: This week we have a great news! The deparment will function as separate one as it was during last 90 year and continue marine and fresh water investigations! We are realy happy and thankful to everyone who wrote letters and signed the petition!
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I'm doing benthic transects to assess coral conditions but I'm having trouble on how to count gorgonians taking into account that they can be perfectly healthy and big but in terms of benthic space they occupy almost nothing.
I could I solve this?
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Hi Diana,
I am not sure what type of benthic transect sampling you are using. If you are using the line transect intercept method then measuring the soft coral holdfast intersect is a very simple way to get % cover of the actual substrate. To obtain the % cover of the soft coral canopy is more difficult, but you can review some of the methods used in forestry to see if they could apply to gorgonians. I have attached 3 papers that you may find useful. The reference sections of the recent papers should give you more leads.
Cheers,
Tomas
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I have analyzed the concentration of heavy metals in water as well as the intertidal sediment. I have not been able to find literature as to why the heavy metal content in sediment is more than the water. Can anyone help me? I would also like to know the permissible range for various heavy metals in marine water sample and sediment.
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I studied the fluxes between sediment and water in heavy metal in very polluted river sediments. Redox conditions and dissolved organic matter have a very important role
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The specimen is under the genus Heterocarpus obtained from Indian coast between the depth range of 250-350. I would like to know the species level identification, based on rostrum deformed nature character of the Heterocarpus, it is doubtful. I Kindly request to identify the species.
Thanking you
Kuberan
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From what I can gather, the various studies that have evaluated decomposition in marine and freshwater habitats have used different methods, and I'd like to know which of these two habitats typically has more rapid decay rates.
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Hi Scott, Antje Bierschenk assessed cellulose breakdown across a freshwater-marine continuum in 10 New Zealand catchments using two different cotton material types. Her work is published: "Bierschenk, A. M., C. Savage, C. R. Townsend, and C. D. Matthaei. 2012. Intensity of land use in the catchment influences ecosystem functioning along a freshwater‐marine continuum. Ecosystems15: 637–651."
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Hi,
I had originally thought that distinguishing between fixed and random factors was relatively self explanatory, however, having read an article on this very subject, I am now not so certain.
The author's decision tree (see below), particularly the part stating that any factor with 2-4 levels 'must' be fixed left me especially confused.
"A) Can I talk you out of including it? (solved – drop it from the model)
A) No I can’t talk you out of it? too bad. Go to B
B) Is it a continuous variable or has only a few levels (e.g. 2-4) → has to be fixed
B) OK, a choice is possible – go to C.
C) Do you want estimates of s1, s2,…,sn (perhaps because you have lots of data and so lots degrees of freedom to burn and are curious how sites differ)? →Fixed
C) Do you want estimates of σ2, perhaps because it saves you degrees of freedom you really need or perhaps because the variance is more interesting (or useful for variance partitioning) than a bunch of estimates of site effects nobody will ever look at? go to D
D) can you either keep the design really simple or are willing to give up p-values→Random
D) You’re kind of out of luck. Change one of your answers and try again"
The article also links to a discussion regarding the recommended number of groups for a factor to be random, which conforms with much of what he has said in his article.
I'm no statistician, so much of this goes straight over my head.
For my particular research question, I'm looking at differences in the composition and abundance of fishes associated with three different coral colony states (live, dead, overgrown by a particular 'coral-killing' sponge species).
I've collected my data from 6 sites, split between two islands. I've also recorded the particular growth form of each coral colony.
To summarise, my factors are as follows:
Colony state (live, dead, overgrown)
Growth form (encrusting, submassive, columnar)
Site (6; nested in Island)
Island (2)
I had originally performed Permanova (in Primer7) using colony state and growth form as fixed factors, with site and island as random. However, as per the advice of the aforementioned articles, I tried again with all four factors as fixed, which produced very different results from my original design. I've tried other combinations of fixed/random, which again, produce very different results.
Basically I'm just looking for any advice as to the correct way to proceed with this, and if anyone could provide a more definitive answer with how to determine the appropriate effect for one's factors.
Thanks in advance.
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Hi Joseph, I'm not sure if this is quite what is meant by Brian McGill. I will review the article again but I felt that his comments were concerned with
  1. parametric analysis of data and the associated assumptions made about that data; and
  2. making the distinction between blocking factors which could confound the results.
So from your description of your data and the factors:
  1. At a superficial level, the categorical values you have mentioned cannot be considered as blocking factors as they are not continuous values.
  2. The use of non-parametric analysis also removes the imposition of assumptions of distribution.
  3. The issue with categorical values is they sometimes represent an aggregation of information which may confound the results of analyses (and this is where the article is focused).
  4. The selection of sites in any experimental design is assumed to be random and therefore they should be considered as random factors in the analysis.
  5. The State and Growth factors are interesting. If I understand correctly, they are to be considered as potential determinants in fish diversity and abundance. If so, they should be regarded as fixed factors. If they are regarded as random factors, the relationship between fish diversity and abundance and those factors becomes substantially more complicated.
  6. You probably know this better than anyone, but results of statistical analyses tend to pose more questions than answers. So the iterative process will required you to look at the results and re-analyse.
It really does come down to your understanding of the ecosystems in which you sampled, and the variable you have collected. Investigating the independence of the factor you have collected prior to any construction of models or multivariate analyses is important. If they are independent, the assumption is that they are not confounding (or "blocking") factors and relationships between them can be compared as causal (or not, as the case may be).
From my point of view, I do not think you have done anything untoward in relation to considering all factors as random in the original PERMANOVA analysis. You could play with the Growth and State factors. However, I would suggest that you consider Bayesian analyses to determine the "degree of belief in an event" because (taken straight from Wikipedia but I've never seen expressed more clearly).
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Dear researchers,
someone has a shapefile of marine sea temperature hotspots worlwide desribed in Hobday & Pecl (2014).
Thanks in advance for sharing.
Regards
Ignacio
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Dear
Mehdi Asadi
thank you very much for your link!
I have also found a direct link for what I was looking for!
Thanks again!
Regards
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I'm planing to travel on vacances to europe, probably to Portugal and perhaps countries nearer to Portugal, as Spain, France and Italy.
I'm interested on visiting labs, institutes, museuns related to my working areas (Fish and benthic ecology, as also environmental education), so, I'm asking for some recomendations from researshers from these countries.
Thanks in advance for any help.
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O Oceanario de Lisboa pode te trazer boas contribuições em Educação para a conservação marinha.
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Hi everyone! need to get the identity of this nudibranch. Collected from the trawl net gear operated at depths 10-50 m. East coast of India.
best regards
Deepak
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Dear Dr Deepak Samuel Vijay Kumar,
This slug looks like Armina variolosa (Bergh, 1904).
Regards
Ravinesh @ Deepak Samuel Vijay Kumar
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I am looking to buy these IN STORE and not make my own. I only want to count the concentration of phytoplankton.
I am looking to preserve phytoplankton from water samples taken in the field. Has anyone tried tincture of iodine to do this?
The tincture of iodine I was looking at was made up of: 2.5% KI, and 2.5 % I2 and then half and half alcohol and distilled water (from the drug store)
The Lugol's solution I was looking at 10% KI, 5% I2, and 85 % distilled water (from amazon)
I am curious to know if I could use off the shelf preservatives instead of the having to buy the expensive ones online
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I prepare my own Lugol,s iodine dissolution ( concentrate):
ACID ONE: 100g KI 50g I2 1in 1l distilled water + 100g glacial acetic for samples with pH<7 (Willen, 1962)
BASIC ONE: 100g KI 50g I2 1in 1l distilled water + 100g CH3COO-Na for samples with pH>=7 (Utermöhl 1958)
i add 0,5-1 ml Lugol /100ml sample
best regards
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Does anyone know what is the average stomach size (weight, volume) of an average common shark species like
Pelagic thresher (Alopias pelagicus)
mako (Isurus oxyrinchus)
blue (Prionace glauca)
scalloped hammerhead (Sphyrna lewini)
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Dear Xavier,
I also recommend this reading:
Body morphometrics, swimming diversity and niche in demersal sharks: a comparative case study from the Mediterranean Sea March 2010 Scientia Marina 74(1):37-53 DOI: 10.3989/scimar.2010.74n1037 LicenseCC BY 4.0
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Recently, there is an emerging series of studies querying that organic carbon burial in blue carbon ecosystems is largely offset by calcium carbonate. Is it true? As I know, calcium carbonate can only be decomposed to calcium oxide and carbon dioxide at temperatures above 840 degree celsius. The sediment temperature in sediments of blue carbon ecosystems can not be so high to decompose calcium carbonate. On the other hand, calcium carbonate is generally not dissolved in water. According to Frear & Johnston (1929), the dissolubility of calcium carbonate in water is 9 mmol per kg water at 1 standard atmosphere pressure. With increasing CO2 in the atmosphere and seawater, calcium carbonate in marine waters may react with CO2 to produce calcium bicarbonate. To summary, I think this query is unreasonable. What do you think about it?
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Considering the rapid rise of interest in blue carbon as a climate change mitigation and adaptation strategies, we argue that calcium carbonate cycling needs to be included when assessing the importance of these globally significant carbon stores as CO2 sinks. Addressing calcium carbonate cycling in blue carbon accounting is timely given that anthropogenic activities and climate change may alter calcium carbonate cycling within coastal ecosystems with unknown feedbacks for climate change. For example, with increasing atmospheric CO2 and ocean acidification, the ratio of released CO2 to precipitated calcium carbonate is expected to rise (Frankingnoulle et al. 1995). Yet increased calcium carbonate dissolution , and decreased calcification rates are also coupled to higher atmospheric CO2, with both processes lowering the rate of CO2 fluxed to the atmosphere. Moreover, partial dissolution of the large calcium carbonate stock deposited in blue carbon ecosystems may provide a buffer to ocean acidification while acting as a CO2 sink. Clearly accounting for calcium carbonates in blue carbon systems is a tricky business.
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The image was sent to me by a diver. It was taken at a depth of 52m in Malta (Central Mediterranean). The 'sphere' was about 1 m in diameter and was moving with the currents. It seemed to be a 'shell' of jelly with no obvious structure. All I can think of is the remains of some gelatinous planktonic organism. Any ideas?
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To Dr. Schembri
We are looking into similar gelatinous spheres from the Norwegian coast, and are very interested in getting in contact With the observer. Could you please give me her/ his name and e-mail adress as soon as possible?
Kind regards, Halldis Ringvold
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Hello
I have used the 'standard' umbrella plastic anchor/dart (developed I believe by Michael Domier) for over 10 years to PAT-tag great white sharks, with much better retention of tag by shark and less or longer premature releases, than with the original titanum 'flat arrow' anchors/darts.
Now I am about to embark in the tagging of smaller fish, Mobula rays.
My question is if someone out there has been using the smaller version of the Domeier umbrella anchor/dart, the one that is 20 mm in length as opposed to the 31 mm ('standard') umbrella dart (see link below)
I am worried that this smaller version of the anchor might not have good enough retention of tags on fish. I will be using mini-PAT tags on Mobula rays that are between 1 and 2.5 m of disc width.
Any positive or negative experiences anyone can share about using the 20mm umbrella anchors for PAT tagging will be much appreciated.
Thanks in advance.
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Hi Alessandro
Similar mix of species to what we have in the Mexican Pacific... We tagged a few M. tarapacana in Brazil and we are writing a paper about that. For those (up to 3 m DW) I see no issue with the 31 mm darts. But for the 1.5 m animals and smaller I would go with the 20 mm darts.
Good luck
Ramón
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Hi everyone,
I would like to know if there are online available and free world-wide datasets of sea surface temperature, net primary productivity, salinity, pH and dissolved oxygen.
Best wishes,
Diego
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Check out the GlobColour project, which started in 2005 as an ESA Data User Element (DUE) project to provide a continuous data set of merged L3 Ocean Colour products. Through their website (http://hermes.acri.fr/index.php) you can access datasets dating back to 1997 and have re-processed, integrated and tested multiple freely available datasets. Depending on your time-series requirements, you may go for more reliable/accurate based on more recent/modern (individually or merged) sensors.
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I have 17 rocky shore sites. From these sites I have quadrat data with species percent coverage data.
From each of my sites I also have an environmental measure for a gradient I am interested in. I am only really interested in how the community changes over this one gradient.
The problem I have run into is that every method I have read about for constrained ordination/ direct gradient analysis seems to require more than one environmental variable. I only have the one environmental variable that I am interested in. I did measure 2 other variables but they are direct proxys for the one environmental variable I am interested in.
I really want to find a way to do direct gradient analysis on this community data using only the one environmental variable - surely that is possible??
I have already done a nMDS of my data in R and fitted a vector using envfit of my environmental variable. But because the method is unconstrained i feel it is not that informative?
Any help would be really appreciated by this stressed out masters student :)
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Hi Meredith,
Constrained ordination with only one explanatory variable is not the best choice. Yes, you can do it, and there is nothing wrong about it; however, as the main purpose of ordination in general is to reduce dimensionality, in this case you only get one ordination axis (despite the fact that you have several species) and thus you only can assess the gradient in one dimension. The alternative (and not sure how great it is) to 'force' the analysis to by converting your one continuous variable into a categorical variable. Of course, you'd need to have a good and sound rationale to assign categories to it (e.g., natural breaks or something alike). Alternatively, you can double-check if your two other variables are correlated (i.e., colinear) with the one you are interested in, and if not, you can still use them in the analysis. Whether they are significant or not in the model is another story...
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It is hypothesized that harpacticoid copepods are the only meiofaunal organisms to develop larval stages because their nauplii share the same habitat as the adults. I am interested to know whether the nauplii (larvae) and copodite stages of harpacticoid copepods are pelagic or benthic compared to calanoid or cyclopoid copepods?
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Dear Moumita, as you know some marine harp. cop’s. are planktonic. So, for them there is no choice like to develop in plankton. Anyway in freshwater some copepods (cyclopoids) had been found in bottom conditions in wintering (look publ. of Natalia Kovalchuk in hydrobiological J. - in RG! But if I understand well we’re speaking about freshwater benthos! Thus, being involved about 40 years with alive samples of different habitats both fresh and brackish waters I'm absolutely sure that naup. & copep. of h. in freshwaters are mainly inhabited the same biotope as adult that is benthos, periphytos (if fast flow of stream) or submerged in case of lenthic basins! This provide much better survivance of youth as protect them against raptor cyclops!
Andrey
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I'm starting my PhD thesis' research on the terminology of marine pollution and I need well-grounded references.
Thank you to those who might help me!
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Hi Marina,
Check this : Marine Pollution Bulletin (2018). Low prevalence of microplastic contamination in planktivorous fish species from the southeast Pacific Ocean.
download in goo.gl/AVseJH .
Best
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I got this jelly fish in huge quantity while trawling off Kochi.
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First Image Rhopilema sp, second and third are Cyanea sp.
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Hello! Between mid-April and throughout June2017 we carried out an extensive sampling to estimate sea urchin settlers through collectors placed on the bottom floor along the Sinis Peninsula (Westcoast of Sardinia , Italy).
We placed 100 collectors at five metres depth, on rocky bottom and Posidonia oceanica meadows, inside and outside the Marine Protected Area of Sinis (according to the method described by Tomas F, Romero J, Turon X, 2004) to evaluate settlement and recruitment of sea urchin Paracentrotus lividus in two contrasting habitats in the Mediterranean (Marine Ecology Progress Series 282: 173-184). Altogether we collected about 500 samples kept at -20 deg. in 70% alcohol. Moreover, we characterized sampling stations calculating habitat and landscape metrics.
However we found many other species of organisms, especially polychaetes, molluscs, crustaceans, other echinoderms, etc.
At the moment we lack resources to perform taxonomic work on these communities.
We are happy to send over the samples to anyone who could be interested. Considering we do have all the environmental data metrics, it would be great to identify biodiversity hot spots in the study area once we have the taxonomic data.
If interested, please contact me at: s.farina@fondazioneimc.it
Cheers!
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hola Nuria! algo de peces si que hay pero no mucho. Mas o menos de 500 muestras los estudiantes han rencontrado larvas teleostea en 30 de ellas (24 en roca y 4 en posidonia).
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We lost a manta net codend/collecting bag on a recent trawl and need to replace one ASAP. Not sure where to buy a replacement in Melbourne. ANy ideas?
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NOAA's instructions for microplastic.
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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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Hi,
As I konw, like stable isotope, amino acid compound-specific isotope analysis, these methods can all used to identify the habitat use and geographic origins and migration of migratory species.
Can you tell me other methods also can be used to do this area. may be otolith of fish.
regards,
BIN
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Depending on the scale of the migration, existing knowledge and budget you have, you might be interested in doing some physical tracking i.e. sampling fish, tagging them (either with passive or active tags) and track them by either attempting to recapture them or detect them respectively.
There is a rich literature on acoustic tags and their use in freshwater at least.
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After reading several articles I am a bit confused concerning the benthic species taken into account for the calculation of species richness and index like I2EC. In the description of I2EC (Grall & Glemarec, 2003) it is mentioned that fixed epifauna should not be counted. What about the vagile epifauna such as many molluscs of hard substrates (Nassarius, Chitons ...) ? I don’t understand why they are listed in mudflat case. What about Serpulidae species like Spirobranchus ?
Concerning the AMBI, normally used in soft sediment habitats, the list of ecological groups contains species like: Balanus trigonus, Nassarius sp., Actinia sp., Tethya sp., Polycarpa sp.
Looks like every study has its own recipe, and it is not possible to know which benthic species are taken into account by the authors for the calculation of each index.
In my opinion, different indices (AMBI, I2EC) must use different lists (infauna with or without epifauna), and each list should be clearly detailled to ensure reproductibility and comparison.
Can anyone enlighten me on this subject ?
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As we all know that more and more marine habitats are degenerating because of anthropogenic activities in the ocean and other reseaons, for example, fishing, climate changes. So we need to do something to change the situation.
Can you guys give me some restoration mehods or suggestions, especially for the coastal area.
regards,
BIN
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Hope this PDF is useful
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Hello guys,
Can you send me some papers which published on Science or Nature journal about ecological integrity or ecological connectivity and biodiversity conservation.
regards,
BIN
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Dear Bin,
Please have a look at these useful PDF attachments.
Good luck
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To understand aquatic ecosystem and its ecological and biochemical characteristics interacting the pollution with the organism, methods for dynamic exchange of DOM and POM is essential. So what are the best methods to understand  exchange mechanism of DOM and POM occurring in different aquatic ecosystems?
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Thanks
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Recommendations on books would be helpful.
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Thank you all for your answers. I will check the books that you have mentioned in your messages.
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Dear friends,
The question as I said in the title, I'm not sure about what problems we will get in troubles, If we use the stable isotope approach.
I hava already read some papers about the fish stocking migration between the different habitats.
I think the most problem is that the different tissues hava the different rate of metabolism, for example, the liver and blood cell have very fast rate, just few days, and the white muscle, fin, or bone of fish can present a long period of feeding habit, and the stable isotope values can present previous habitat information. Moreover, the size of fish we collect may be also can influence the result of the stable isotope values, but I'm not sure about it.
you guys can give me some suggetions or advices about the question as much as you konw, if so, thank you very much.
Regards,
Xie Bin
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Hello, your question is very general, the problems in the use of isotopes will depend on the type of isotope you are using. I recommend that you read this book that will help you answer all your questions.
Hobson, K. A., & Wassenaar, L. I. (2008). Tracking animal migration with stable isotopes (Vol. 2). Academic Press.
Viljoen, G. J., Luckins, A. G., & Naletoski, I. (2016). Stable Isotopes to Trace Migratory Birds and to Identify Harmful Diseases: An Introductory Guide. Springer.
I send it to you in attached
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Hi,
According to Quieros et al. 2013, Carcinus maenas falls within the bioturbation class of 'Regenerators'.
'Regenerators' are excavators that dig and continuously maintain burrows in the sediment, such as the fiddler crab Uca spp (see Kristensen et al. 2012). However, I doubt C. maenas is a typical regenerator as it does not maintain a burrow system.
My question to you is, how would you classify this species in terms of bioturbation? In my opinion it could be classified as a surficial biodiffusor as it finds most of its food in the top few cm of the sediment (even though it may occasionally dig deeper for food). I have to mention that the study site is a Dutch intertidal sandflat where we mostly find small specimens.
It would be very helpfull if you can let me know on how you think about it!
Thanks Pieter
Queirós, A. M., Birchenough, S. N. R., Bremner, J., Godbold, J. a, Parker, R. E., Romero-Ramirez, A., … Widdicombe, S. (2013). A bioturbation classification of European marine infaunal invertebrates. Ecology and Evolution, 3(11), 3958–85. https://doi.org/10.1002/ece3.769
Kristensen, E., Penha-Lopes, G., Delefosse, M., Valdemarsen, T., Quintana, C. O., & Banta, G. T. (2012). What is bioturbation? the need for a precise definition for fauna in aquatic sciences. Marine Ecology Progress Series, 446, 285–302. https://doi.org/10.3354/meps09506

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Hi Pieter
The bioturbative effects of the shore crab Carcinus maenas are limited, since many live in hard-substratum environments. But indeed, in sandy areas it shows either locomotion (small footprint but many legs!) or temporary burrowing activity. Burrowing may be either for finding food with chaelae or for hiding. In sandy areas, the shore crab may temporary hide in the sediment completely by digging in backwards. It does not dig deep as it keeps contact with the sediment surface.
This being said, following Kristensen et al. (2012), I would consider the shore crab an 'epifaunal biodiffusor'. C. maenas is not well adapted for living in and moving through the sediment like the examples mentioned for 'surficial biodiffusors' (e.g. burrowing sea urchins). Also following Kristensen et al. (2012) it cannot be considered a 'regenerator' as does not maintain burrows continuously.
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Before posting this question, I'd like to state that the following must not be regarded by any means to a discussion on catching marine mammals in EU seas.
Why are marine mammals (namely very common species of dolphins and pinnipeds) strictly protected in EU waters while Bluefin tunas, rare and collapsing as they are, are still apparently overfished mainly in the Mediterranean's W basin? Do you think that this has something to do with the "cuteness" of marine mammals and the fact that Thunnus thynnus is "just a fish"?
Many thanks for your contributions.
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I think to fully answer this question one would need to analyse why most western people would give marine mammals higher ethical importance than fish like tuna. Such socio-cultural construction is surely very complex. Who would eat "flipper" or his bigger brothers and sisters, the whales. To search for economic explanations is important, but it finds it limitations as whale meat is also costly, not necessarily in Europe, but Japan for example.
In the Solomon Islands every year thousands of dolphins are killed, which causes much outcries, but such outcry would never happen, when the same fate would meet fishes……, no matter how threatened….. The example of the Solomon Islands might suggest that the difference between fish and mammal is not only a European aspect.
The socio-cultural construction of what should be consumed from the ocean and what not has become the basis of strong protection efforts (e.g. Greenpeace, consumer societies which introduced the dolphin friendly tuna label). In some cases, e.g. the protection of most of the whales from getting extinct, has ecological reasons, but do we condole the extinction of the dinosaurs for example. While I speak in favour of protecting bio-diversity it is still worth reflecting, what ethical principles are behind such calls and how these ethical principles are socially constructed and if it makes differences what animal right are concerned.
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Hi everybody
I'm trying to culture Nannochloropsis oceanica CCMP1779 (axenic) under heterotrophic conditions. For the methodology I'm following previous studies where they cultured other Nannochloropsis spp. and trying to do it under the same conditions. Briefly I inoculated some phototrophically (f/2) growing culture into a new medium made of f/2 and 2g/L glucose and incubated in the dark. However nothing has been growing for 2-3 weeks, while the dark/light control (in the same medium) grows very fast. Therefore Nannochloropsis is clearly not growing heterotrophically and the problem does not come from the medium.
Does anyone have any suggestion on how to grow Nannochloropsis heterotrophically? are there substrates more suitable than glucose for heterotrophic cultivation? Is it possible that other Nannochloropsis spp. can grow heterotrophically while N. oceanica can't?
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Dear all, thanks for the suggestions and sorry for the late answer. I finally did not succeed to grow Nannochloropsis with glucose.
I think the inhibition might be to the difficulty in transporting glucose inside the cell.
Sergio
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I am doing a GIS project on different coastal ecosystems and need a representation of such ecosystems. Corals, Mangroves and Seagrass I have, but kelp is missing...Thank you!
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I'm not sure where you can find this shapefile, but it's likely the authors of the attached 2016 paper "Global patterns of kelp forest change over the past half-century" will have one. See Figure 1A. 
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Dear colleagues, thank you a lot for your reply, excuse me for the time taking  and for photos quality
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Collection labels shows that this specimen was collected from South China Sea (ca. 14°N, 112°E,>1000 meters depth).
The specimens are very small. One of the specimen looks like having a pair of antenna. Uniramous parapodium with spinigerous compund chaetae. Parapodium well developed with dorsal and ventral cirri.
I don't know which family it belong to.
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Hi! It is a Syllidae. I would try Exogone, Parexogone or similar genera. I hope this helps. Cheers!
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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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In case you are still interested by this topic, we've just published the paper this question was about. There are some accurate conversion factor calculation in it.Hope it contributes to bust the myth !
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Dear All,
I have collected this Jellyfishes from Visakhapatnam Fishing harbour. I think one is Crambionella sthulmani, other one is Rhizostoma pulmo Anybody kindly identified and confirm it species level.
Regards
K. Silambarasan
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 Dear, 
         Please take jellyfish image within the water .Otherwise identification is difficult process. 
First image is Crambionella stuhlmanni. It is common species in the  East coast of India.
Second image without oral arm I think this specimen has violet Steak in the exumbrella. So it is Thysanostoma loriferum .
Third image is  juvenile stage of Cyanea sp.
Fourth image may be Netrostoma sp. If you have this specimen  please take photos within aquarium tank and send me. I will try to identify .
Fifth one is Pelagia noctiluca .
Please give numbers to the images for identification .
I hope this helps, but if you need more assistance, please let me know! My email is panavoorriyas2@gmail.com
Sincerely, 
Riyas A
 
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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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Dear Pierre,
take a look to the literature in experimental works using inorganic or methylated 203-Hg exposure in fish. you will have a good insight on the biokinetic processes.I can send you some refs by email if you want. Best, Marc
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These structures appeared spontaneously attached to the bottom of my culture wells where I maintain mediteranean sea anemones larvae. Cultures are kept in unfiltered seawater 25°C. 
On the pictures, the largest cells make about 10µm
(Sorry for the poor quality of the pictures)
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Dear Thamilla, by the pictures, it is not easy to say which species. did the cells could form the round colony? The cells would be zooxanthellae if they were found in the anemones cultures. I agreed with Nancy. However, zooxanthellae normally has the flagellates to swim . you could check them . 
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Hi guys,
By analysing the microbial metagenomics, I found lots of genetic traits related to metal resistance and organic remediation, suggesting the water pollution in ambient seawater.
I've heard that Kaneohe Bay used to be a good snorkelling place in early 90s but then it was polluted.
I am not familiar with the marine chemistry/pollution field, if anyone has the data or knows where I should look at, please let me know. Thanks in advance.
Kind. Fang
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Hey Fang, Did any report or paper ever come from the study on marine microbial metabolism? May I ask you who you were working with? Would love to hear more about your results as I am looking to start some microbial sampling in the bay myself. Thanks!  
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Please explain sandy shore adaptations in marine invertebrates, add specific comments on their physiology.
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There are numerous adaptations that marine invertebrates have in sandy shores. In order to not be swept away from the powerful waves, marine invertebrates such as the paddle crab use paddles on their legs to burrow into the sand (Science Learning Hub 2012). These invertebrates also use this mechanism to prevent desiccation. 
Other marine invertebrates, such as olive snails, have streamlined body shapes (Cabrillo Marine Aquarium 2012). This body shape allows these organisms to burrow into sand easier and to let water pass through right their bodies. 
In addition to that, an issue in terms of access to oxygen arises when these organisms burrow in sand. To address this issue, a siphon, otherwise known as a specialized breathing tube, is used to gain access to the dissolved oxygen from the water by extending this part to the water from the sand (Cabrillo Marine Aquarium 2012). The bent-nosed clam actually makes use of this tube. This particular part is efficient since it also has the ability to prevent sand from gaining access to the gills of the bent-nosed clam(Cabrillo Marine Aquarium 2012).
References:
Cabrillo Marine Aquarium. 2012. The sandy beach environment [Internet]. Los Angeles: Cabrilla Marine Aquarium; [cited 2017 May 12]. Available from: http://www.cabrillomarineaquarium.org/_publications/tr-ss-sandy-beach-environment.pdf
Science Learning Hub. 2012. Adapting to marine habitats [Internet]. New Zealand: University of Waikoto; [cited 2017 May 12]. Available from https://www.sciencelearn.org.nz/resources/1126-adapting-to-marine-habitats
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These corals were observed in the central Red Sea. In some of these photos Acropora if it is possible I need species name. For other even genus name is enough.
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Hi, Jaafar, thats nice to read you - it seems that you are still looking for corals...
Most pictures also show Acropora, but not in all cases its easy to know what coral in particular you're asking for. The photos ## 2 and 3 show some Xeniids, possibly Ovabunda sp., but for species ID samples would need to be checked. Further on # 3: Pocillopora, Millepora exaesa. Photos ## 8, 9 remind me of A. humilis, may be # 5 as well, together with 2 colonies of Montipora sp. For the other Picture I can't enlarge some details, if you send the pictures directly to me, I could try to ID the genera. Good luck for your work, cheers, Goetz.
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I am working on low latitude Paleogene shallow marine fauna of W India and would like to understand the trophic scenario of this fossil community. Where can I find relevant information on extant shallow marine fauna for comparison?
Thank you.
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Siddhartha:
Your question embraces broad spectrum of shallow marine environments, but this classic link would provide you essential insights:
Best
Syed
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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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We found this during my colleague research survey on Seribu Islands, Indonesia. We found this only living on lagoon systems. We was thought this is kind of sponges, but we still not find the relevant publications. Can anyone help us for recommended publications or links? Many thanks, 
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Hi Singgih Afifa Putra
I'm sorry if this answer is too late. But i'm just replying for what it is worth. I am working in the Andaman Islands on sponges and I have frequently encountered the species seen in the first photograph and I believe it to be the species Lamellodysidea herbacea. I'm not sure if the following two images are of the same sponge. they look a little different.
I have also seen it to be growing on top of corals smothering and killing them. It is also generally more common toward the shallower reefs.
Best Regards
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I am conducting a survey which i will use as primary research for my extended project. 
If you can you may, State which of the following is the most destructive fishing practice. You may also give a reason why you choose that.
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Hi Alex. I fear that the answer depends on what you understand by "destructive" and what are you focusing at when assessing the effects: endangered species, community-wide effects, ecosystem services, or other.
Destructive can be translated into a number of attributes as being non-selective in the target, persistent in its effects, or effective in removing individuals. From this perspective, explosives and cyanide are the less selective and effective, while ghost fishing is the most persistent and less effective.
When one comes to focusing on response variables to assess the severity of the effects, shark finning remove top predators that are both important in structuring the community, can eventually lead to the alteration of ecosystem services (for example through releasing prey fishes and thereby altering the balance between coral-dominated and algae-dominated ecosystems) and generally endangered.
Still one can put the question in the perspective of wide-scale management for conservation purposes. Then other practices like bottom trawling (cited in the previous post) and also drifting nets would have higher impacts. The former because of its spatial extent and pervasive effects through communities and ecosystems. The second because its impact on charismatic species like dolphins, whales and turtles, which raise public concern and trigger in-the-field actions.
Possibly a multivariate approach in which you combine the scores given under different criteria for each activity, tailored for the societal values rooted in your study area, would provide a more complete albeit perhaps not definitive answer.
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The picture of this brittlestar is from the North West Atlantic at about 900 m. depth. The location is near the Greenlandic coast.
Can this Brittlestar be confirmed as an Ophiomusium lymani ? or could I be looking at something completely different
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Thank you for all your answers. I have something to work with now :-)
Helle
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I need to calculate LOD in Hg analysis of fish sample. My method is;
Blank: put 10 mL nitric in microwave vessels and run the program and volume up to 50 mL and read (result received in microgram/L)
Sample: take 1 g sample+10 mL nitric acid in microwave vessels, then run the program, 
My equation is for LOD=mean+ 3*standard deviation
But I receive blank reading in microgram/L unit (See attached excel sheet), then how I calculate LOD? Can you give the example or correct my excel sheet
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I have a new AAS instrument, so can you give an idea what I need to do to validate the method using AAS. such as LOD, LOQ, sensitivity etc. ?
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I will be increasing T by 2C every few days and need a heater that can do this accurately for a few gallons of seawater
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Tubular Immersion heaters are best option. It can be designed to based on Tank dimensions n with a suitable control System ( Panel). We make such heaters.
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Dear all,
I am looking for studies coupling experimental and demographic models simulating global change scenarios. For example, studies measuring the effect of temperature on the survival of individuals in controlled aquariums, and then incorporate that data in demographic models (such as matrix population models). I would prefer studies on the marine environment; however, given their scarcity I am also opened to terrestrial ones. 
Thank you all. 
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Thank you John!
That was definitely useful!
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i exposed mussels to different chemicals, same concentrations, different time of exposure, and i got the results for different organs, also i used DMSO as carrier for one chemical, could you please tell me which one is most suitable for mein, ANOVA one way or two way, beside of this i was confused about the effect of carrier how to normalize it (substraction or  ratio relative to control) or just see if the difference relative to control is significant or not? thanks in advance
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Dear Younes 
ANOVA IS GOOD FOR SUCH DATA 
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 Since early 2015, on Bonaire (Dutch Caribbean), I sometimes encounter 'humps' on scleractinian corals.
They feel like cartilage or a hard gel and have a diameter of about 10-20 mm. The surface has a whitish-violet colour, possibly due to fine filaments. In cross sections some concentric layers may be recognized.
These humps were encountered on healthy corals (Orbicella faveolata, Agaricia agaricites), on morbid corals (Orbicella annularis, Siderastrea siderea), on dead coral next to live coral (Madracis auretenra) and on dead coral surfaces (unspecified), see enclosed photos.
Who has seen these humps as well and who knows what they are?
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In Reunion, it seems we have the same whitish-violet "humps of Cyanophytes", Phormidium sp. Humps are ca 5 cm in diameter and they occur on corals in eutrophic/dystrophic areas (Naim et al., 2013a). They have a "stromatolit-like" internal structure.
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Dear researchers,
I’m evaluating marine species distributions off Northern Humboldt Current System (Peru). So, I wish calculate some overlapping index between them (e.g. Niche Overlap, Gotelli et al. 2015). To this, I need entries (values) in order to construct the matrixes. I have logistic outputs from MaxEnt (rasters and suitability values). How can I use these values? Need I some transformations? Thanks in advance for your helpful. Miguel.
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You can also use the ENMTools software (http://enmtools.blogspot.com). It comes with a detailed tutorial explaining how to use maxent's output to run niche overlap analysis. But basically you will just use the ASCII files of predicted habitat suitability. 
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this cowrie was busily grazing on a reef flat located during the low tide. Would be happy if someone can identify the species. The spots are orangish and small on a white background. mantle has a dark brownish line on the periphery after which hairy structures are seen. 
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Hello Samuel - Your specimen is undoubtedly one Erosaria turdus and, more particularly, an Erosaria turdus winckworthi Sch. & Sch., 1938, corresponding to the most eastern population of this species (Oman-Pakistan-India). 
All the best, Gianluigi
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The impact of ecological factors on the content of bioactive compounds sulfated polysaccharide in brown seaweed
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A very good book, with plenty of lead references is:
Seaweed Ecology and Physiology by Hurd, Harrison, Bischof and Lobban 2014. Second Edition. Cambridge University Press.
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Anything about their recovery as a community, the succession in assemblage, and their function in the recovery of the reef as a whole.
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Sorry, not me
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We are planning to change the traditional paper sheet and pencil by waterproof or rugged tablets to record survey data onboard during oceanographic surveys, including biological samplings. We would like to know your opinion about brands, models, ease of use and existing apps for introducing data. Thank you!
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See: David R. Gloeckner,
 IMPROVEMENTS TO DATA COLLECTION IN COMMERCIAL FISHERIES USING ELECTRONIC REPORTING METHODS: COST/EFFICIENCY AND IMPLICATIONS FOR USE IN ECOSYSTEM MANAGEMENT
He has a profile on ResearchGate and heads the NMFS SEFSC Electronic Logbook program for collecting commercial fisheries data.
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Copepodes , plankton ; Acanthocyclops robustus
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hi Salah MAhdi ;
thanks for al this articles 
greetings
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Fish Visual Census (FVC) is a widely used non-destructive method to indentify, count and weight fish species (targeted or not) in an area of interest, usually reefs or seagrass meadows. Usually, FVC are conducted once per year, preferably during summer periods (bias ?) where the water conditions are "friendly" for the divers and snorkelers. But, how such sampling approach is correct in the representativeness of the fish species and the biomass ? Do studies with monthly data exist (am not aware of any) ? Do summer period is "good" for all species (in the Mediterranean for example) ? Do the designation of MPA or the ecological evaluation of an intervention need more data than a random month in summer period ?
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For the thesis I am doing a job on these organisms in Grado lagoon.
Unfortunately I have doubts about age determination, because the literature shows conflicting data. I would ask if it's possible that I have P. marmoratus up to class 2+ and for K.panizzae1+.
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I am not a sponge person. However, recently there is a company promoting to gather this sponge for commercial export. Given the commercial use of resources, it will eventually deplete the wild population. Is there an existing propagation protocol for this sponge?
The photograph was taken from Palawan waters 9 meters deep.
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Would it be right to expect that the company proposing to harvest this sponge should provide an identification as a minimum requirement ?
Sorry, but sponge IDs from pics (colour pics are better) are often not safe.  You'll need a sample and then do a spicule analysis accompanied by sections to determine arrangements of spicules within the tissues.  On big specimens, small samples from surface, base and interior would be needed for the spicule analysis.  Of course I'm assuming that a sponge of this size will have spicules...Good luck.
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Such tools would be useful to sense if it's present in oyster beds during peak production
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Sounds like a proposal for the USDA!
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Microscopy, of the lung of P. maculata,  has revealed a layer of large (20 µm) spherical inclusions. EDS has indicated that the inclusions are predominantly calcium carbonate.  A review of the literature suggest that the inclusions could be hemocytes, calcium cells, or rhogocytes, but the difference between them is unclear. Some papers use the terms interchangeably, while others seem to differentiate between them. One paper even suggest that one form leads to another.  I would greatly appreciate any insight you can give on the matter.
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Thank you, Ken, for clarifying this. But if P. maculata also estivates, it is still possible that it differs from P. canaliculata in the mechanisms against the oxidative stress of arousal from estivation. This might be worth pursuing, Kristy.
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Dear community,
I'm currently searching for a logging device to record the current velocity/strenght and in the best case also the current direction. The device should be not too expensive and robust, to deploy it in the field for several months. Suggestions would be very welcome.
Cheers
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Hi Markus,
Already mentioned by Audrey and Daniele Nortek and Valeport are very good and reliable instruments. I would also suggest to look at Aanderaa data instruments - they have very reliable single point current meters (Seaguard RCM) measuring current speed and direction at the depth of deployment. If you want current profile also worth looking at all time classic TRDI ADCP. Unfortunatelly all oceanographic equipment is pretty expensive... Wouyld also suggest to browse around the both websites to see the ways to deploy. Please see the links below, and hope this helps:
Aanderaa:
RDI:
Best regards,
David
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I am trying to clarify progress being made in algae fuel development in U.K.
I am trying to establish marine algae models being studied at present in U.K.
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Hi
Since a whole year The James Hutton Institute (Dundee Scotland) has been doing research on seaweed in collaboration with Marine Biopolymers Ltd (Ayr Scotland) which is a company that sustainable harvest seaweed and industrially process it to extract alginates.
The aim is to explore seaweed content, qualify Marine Biopolymers Ltd by-products from the main stream of alginate production and develop new seaweed products.
I have already published some work  here at Research Gate if you want to take a look and follow.
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There are incandescent, fluorescent, etc. like light sources. I am going to capture different kind of nocturnal and aerial insects to identify prey availability for insectivorous bats in agricultural lands. For that, I plan to use light traps. What is the most effective light source for this study?
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Hello Dear
Insects can perceive light in the 300-650 nm range, but prefer light that is between 300-420 nm which includes UV light.  A light’s UV output is probably the most important factor in its attractiveness to insects.  Since most insects are attracted to UV light, this is why most ILTs (Insect Light Traps, including bug zappers) utilize UV/blacklight bulbs as their source of attraction. Insects generally see 3 colors of light, Ultraviolent (UV), blue and green. Bright white or bluish lights (mercury vapor, white incandescent and white florescent) are the most attractive to insects.  Yellowish, pinkish, or orange (sodium vapor, halogen, dichrom yellow) are the least attractive to most insects.  When white incandescent bulbs were all that was available, the advice was to change them to yellow incandescent bug bulbs.  Yellow and “warm white” bulbs tend to be more like sunlight and are less attractive to insects than “cool white” bulbs that have a more bluish tone.  Red bulbs are even less attractive to insects than yellow, but red provides little visible light to humans and it carries an “undesirable” social stigma from decades ago. Best regards
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This far the species are identified as:
1. Diadema setosum
2. Sarcophyton sp
3. Heteractis magnifica 
4. Red Mushoom / Stone ? - what is the latin name?
5. some kind of sponge?
6. seastar
7. Zebrasoma scopas 
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6 is definitely an asterina star. Hard to elucidate a species in a photograph. That is a common "pest" in the aquarium hobby. Some are known to feed on crustose coralline algae, while others will feed on zoanthids. 
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I am analyzing the variations of observed species number in a temporal gradient. When I conducted a poisson GLM, I found that the scale parameter was about 0.25. The dispersiontest() function under the AER library also indicates significant underdispersion.
I know I can use quasi-poisson model under the overdispersion condition. When I searched it, I found some documents stated that Quasipoison could also be used underdispersed data, while others did not suggest to use it. 
What I would like to ask is, may I use a quasi-poisson model for strongly underdispersed data. If not, what do you suggest instead?
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Hey. I've just came across this article, freely available, and has R code ! Under-dispersed count data in ecology might not be as rare as it seems but surely has been overlooked. I could see more clear now how a sampling situation in which we sample critters in quadrats/points could lead to under-dispersion in the counts due to both ecological and observation processes (imperfect detection) and how this two things are actually confounded. The fact that my detection-naive models (e.g. Poisson GLM and allies) indicate under-dispersion but my detection-corrected models (N-mixture w/Poisson family) indicate the opposite (GOF analysis showed that my observed variance is greater than the expected under my best model) is maybe linked to that. Now, when I specified a Neg. Binom. of ZIP distribution for my N-mixture (just with an argument in unmarked) I still have mildly problems with lack of fit but overdispersion seems to be better accounted for, comparing my models with AIC/BIC and because of the degree of discrepancy with the bootstrapped GOFs. So, I am still unsure on many things, but I tend to think that, for my bird species, the reason for having smaller variance than mean values is more tightly linked to detection error, probably related to habitat (site) covariates or other survey-level specific covariates I did not sampled or included in my models (for detection I only used julian day, minutes after sunrise and observer ID). Hope some of this considerations help! This thread and the reading and writing of all above really helped me to understand my data and models better, and to distrust them all! Hopefully though we can get to some useful ones.
Lynch, H. J., Thorson, J. T., & Shelton, A. O. (2014). Dealing with under‐and over‐dispersed count data in life history, spatial, and community ecology. Ecology, 95(11), 3173-3180.
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Is any non leathal sampling method that we can use to collect tissue from marine gastropods/bivalves in situ that will not cause post sampling issues ?
E.C. sampling on Charonia variegata ? Or even on the bivalve Pinna nobilis ?
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Mantle tissue can be snipped in some groups of bivalves. I've taken samples from freshwater bivalves species, but not sure about Pinna. I know Pinnidae subjected to trawling damage can repair themselves to a certain degree so a small snip of mantle tissue could be relatively safe.
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I am interested in breeding three-spined stickelback in aquarium.
I want it to last at least a year. Does anybody have experience? Is it possible on room temperature, what they eat, how to find male and female specimens?
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Hi again. Been to Tartu so I can imagine that you need artificial salt water if not storing the animals at a field station (any at beautiful Saremaa?). Actually you have freshwater sticklebacks so why not use them? depending on your research question of course. There could be some in lake Peepsi ?
I dont know how it works with art salt water. We used continuous flow of deep salt water (34%0) taken directly from the sea and thus having the seasonal temp variation. I think our minimum in winter is around  8-10 degrees.
Regards Susanne
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This species was found in the mixed biofilm cultures...
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Oedogonium is unbranched filementous form with cap cells and oogonia ( these are identification marks for Oedogonium) 
Further Coleocheate is discoid structure with reduced erect system and  I don't know whether it is Coleochete or not
I strongly believe it may be cluster of algal forms which form the bloom. so better to isolate the individual filaments and examine under the microscope.
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This specimen was found to grow in cultured biofilm samples...
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please give details such as size of the filament, is it branched or un branched, type of the chloroplast and  how many cells are present in the filament for proper identification of the species
Thank you
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I have several 1L bottles frozen at -80 deg.C and need to filter them for eDNA analyses. What is the safest way to melt the water?
i'm testing with two samples by leaving them at 4 deg. C but it takes a very long time (>1.5 days and its still half frozen) and i'm unsure that it won't damadge the DNA, since part of the samples is already liquid since approx. 1 day.
Thanks for any comments on this!
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Thank you for your comment and suggestion!
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Organisms are collected by trawl net from sandy-mud substrate. First of all I would like to thank to everyone who send the answer ant try to help me. Than for one who asked: samples were collected from south Adriatic Sea (Montenegro) at depth from 80-100 m. I put more photo about size and dissection.  
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Having seen the new image of the dissected specimen, I reiterate my original opinion that this is probably the anemone Actinauge richardii, or if not, a closely related species. The retracted tentacles are visible and the mass of sediment 'inside' the animal is not actually inside but the pedal disc forms a concavity that is filled with sediment such that the animal becomes firmly embedded. The degree of rugosity of the body depends in part on the state of contraction of the animal. See also: http://www.marinespecies.org/photogallery.php?album=4487&pic=1774
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Hi Malacological Community - Can somebody help me with pdf about recent Retusidae from Red Sea?
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Hi Gianluigi, you can download a pdf of Retusidae and Co. in the WEB by Gruppo Malacologico Livornese. It is quite complete and accurated, even for those taxa which remain doubtful. It is not very good for pictures, which however fit perfectly the description or are from original diagnosis.
Good luck
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Nemo drill driver 2 Does anybody have any experience in using the Nemo drill diver 2 for underwater drilling. I am aiming to anchor down some cages onto the seabed composed of limestone at depth of about 8 m (i.e. relatively soft rock). Now I have seen this drill on the internet
and it appears it could be a good alternative to the pneumatic drills which are more expensive and their use appear to involve far more logistics. I would love to hear some experiences of drilling underwater and which pieces of equipment work best.
Many thanks already
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Hi Hilmar,
We do quite a bit of drilling underwater for our monitoring site set up. We have a spitzner drill.
Nemo drill looks good in theory. the video looks pretty convincing. If it has a good hammer action it should work. if not then it is prob useless. we had an old underwater drill with no hammer action and it was ineffective. the spitznas is not too cumbersome. need a few spare cylinders to take down with you or with your buddy. got video of it somewhere if you want to see. let me know if I can help anymore. cheers, Charlie
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How can I consider together the low genetic diversity (haplotype diversity:0.0000 to 0.042 and nucleotide diversity: 0.00000 to 0.00089) and high FSH values (-0.0546 to 0.29807) seen in marine fish species.
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Sorry,
I wanted to write Fst (pairwise)
Best regards
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Brazil exported this year 16.594 kilos of shark fin, how many sharks would that be?
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In order to answer that question you must know which species are the main target of fisheries, as well as the relative contribution of each species to the total numbers. After that you will need the average weight of the species involved and the relative contribution of the fin to their body weight (You can use the suggested number but you need to backup that figure with a published work, or do your own research).
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Can any body help me to identify this animal collected from estuary, south west cost of India?
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First one is Leeches and second one is damage nemertean, last one is  dorididae (Opisthobranch) juvenile 
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we project to clean a newly invaded site with Caulerpa racemosa, is there an ecological/biological method to use?
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Can any one help me in identifying this Rhinoptera sp. and and provide literature on its taxonomy. 
Details:
Area of collection: Andaman sea, Disc width:49cm, Tail length:38.5cm, Sex: male. spine present.
regards,
pradeep 
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Pradeep:
At one stage R. jayakari was considered as a Synonym of R. javanica. Since you have access to the actual specimen, you need to carefully assess the taxonomic features, as also suggested by Ronald and make your own judgement, as it's occurrence in Andaman-Nicobar sea would be extremely important. Do have a look at this asked for link:
Best
Syed
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I'm writing an article about abnormal gonads in walleye pollock. Such gonads were met in large and old fish, but It looked like the ovaries of the immature pollock females according to their color and size. Histological analysis showed the different degrees of degradation of the germ cells.
What the best way to correct name such gonads?
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Thank you very much for answers.
 It cannot be "resting" or "regressing" gonads. Regressing phase continues for a relatively short time. I worked with such gonads and they look different: gonads are larger, with hyperemia; a large number of postovulatory follicles and atresial vitellogenic or hydrated oocytes in female; residual resorbing sperm in male.
This group of examined abnormal gonads includes male, female and sterile gonads that look very similar. Only histological analysis reveals gender or infertility.
Different types of abnormal gonads occur in walleye pollock: e.g. bisexual, with total atresia. And I try to describe ”new” type of abnormal gonads in this species.
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In the recent years (5 to 10 years), the flow of groundwater toward a dam reservoir contains about 5 mg/L of H2S. This sulfur was absent in the previous years. The sulfur can corrode dam facilities. Is it possible to control entrance of sulfur (that is mainly derived from geological units) by some mechanisms? Is it possible to introduce some electrical charges in upper sections to change the Eh of groundwater? Does changing Eh values can change the position of Sulfur (S) in Eh/pH diagram so that a neutral S is achieved? 
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Dear colleague,
You can use hydraulic barrier to prevent such groundwater flow. This can be achieved through using surface water in the reservoir itself. 
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If anyone has done GCMS for tetrodotoxin detection, please help me to know the compound names for the characteristic fragments of 2-amino 6-hydroxymethyl 8 hydroxyquinazoline that forms peaks at 376, 392 and 407 m/z. I need to find out in the library to interpret my results. 
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We have GCMS
You can send the sample to me.
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I'm going to extract Hirudin from leech so i want to know the best conditions to breed leech for maximum extracting of it.
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 Method for extracting Hirudin from leech saliva
may be useful
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Collection from Bhavnagar Coastline,Gujarat, India.
It's difficult to identify! clypeomorus batillariaeformis.....!!! or clypeomorus bifasciata....!!
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Hi my friend - I think that your examples do not correspond either to C. batillarieformis nor to C. bifasciata, but rather I would think Clypeomorus inflata or C. pellucida, the latter typical of mangroves, although according to the revision of Houbrick these two species would not be present in your area. You have the revision of the Genus Clypeomorus of Houbrick? If you do not have to tell me that I sent you. See the pictures.  Best, Gianluigi
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I would like to know the sedimentation rates of a shallow waters (15 meters). It is very steep, and I have only 6 week to measured. But we could dive to install some devices....
Thanks a lot
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The problem ius that almost any device you might install has the potential to affect sedimentation pattersd around it if there is any turbulence at all in the environment. Is the bottom sandy, silty, clayey or organic? If is it very fine grained, then a simple can embedded in the sediment collect after a period of time would give you a rough estimate, particularly if you do a few of them. In coarser sediment you could also try doping the surface fo teh sediment with a marker - maybe colored glass ground to the same grain size as the sediment - and then take a very short core at the end of the period to measure how deeply that doped layer was buried. Do you know what the bottom sediment is like? 
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i have been collected my samples from Persian gulf, hard bottom, that they were attached to a soft coral.
i think it is a Ophiothrix sp, but i cant identify it in species level
if you know its name, please send me a reference
thanks a lot
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Definitely not Ophiolepis. Ophiotrichidae is correct and I think it is Ophiopsammium not Ophiothela but needs to be verified with literature and close examination.
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I am using GAMs in mgcv to look at relative stem densities and weights for a paired dataset (control and treatment) stem data for each sampling location. Should my response variable be, for example, the stem weight ratio of treatment/control or instead, would it be more appropriate to have the treatment stem weight as the response and include the controls stem weight as a co-variate?  
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Hi John,
It's usually best to model the raw data, which in this case is stem weight with control/treatment as a covariate. It can also be easier to choose what distributional assumption you want to make about your error structure of the raw data. For example the error structure of weight will likely be best described as a log-normal distribution. On the other hand, what is the distribution of the error structure of a derived ratio between two log-normal distributed weights......not quite as clear.
Wish you well,
Dan