There are standard procedures for assessing contaminants in wildlife that are used by the US and Canadian federal agencies, I would suggest you start there. Also mercury seems to distribute fairly homogeneously, but if you start looking at PCBs of other hydrophobic materials, they partition strongly into fats, so muscle tissue will give you a different result than viscera, fat deposits, skin, etc. Best approach would be the chick-o-matic whole organism homogenizer (requires a sturdy stomach). Mercury levels can also be determined in hair or feathers, which gives you the non-destructive option of looking at loads in adults.

Feathers are a good non-destructive sample for estimating pollutant load in birds. However , I wish to ask an extension of the question already asked here. I collected some bird feathers from dead birds in Antarctica . According to literature, the contaminants accumulate themselves in feathers, shafts and hair. Is there any difference in accumulation of different trace metals? like As, Hg, Pb? Is it fine if I apply the similar digestion procedures to estimate them using atomic absorption spectrophotometry?

I fully agree with the comments of Anant Pande. But along with feathers, organs like liver, heart etc. may be taken into account.

I am not sure about differential partitioning of metals within organisms, but differences between species are sometimes significant even in the same habitat. Try to keep your samples species-specific.

A suggestion is to contact a board certified wildlife toxicologist who can further direct you to specific tissues that would be best to look for heavy metals, organophosphates, organochlorides, and other pesticides/toxicants. Tissues that are optimal are subcu. adipose, brain, liver, feather shafts, and crop/stomach contents. It is really specific to the toxicant you are focused on since many tend to have a specific affinity/sequestering towards a particular tissue. Also the determination of trace vs. quantification levels is feasible.

I work closely with the California Animal Food and Safety Laboratory outside of UC Davis and the laundry list of toxicants is extensive with HLPC, LC and many other diagnostic tools. However the the use of a vet toxicologist will most importantly give you context to the results and give the potential clinical/environmental deleterious manifestations from exposure or poisoning.

Hi Mourad thanks very much for this answer. We are near the site of a new hydro electric development, with flooding starting in 2017. I am most interested in starting a program to monitor methyl mercury. Aboriginal people in the area also collect seabird eggs (tern and gull eggs) as part of their traditional harvest. I think it's important to start to document mercury loads in these species.

Hi Keith, I as a vegetarian, strongly support your move to use carcass (not the man-killed) for research purpose. Please let us know of the research outcomes. Good luck. McKenzie Lim.

Thanks Mckenzie, will do

Hi Keith

Just to let you know that Vets Without Borders (based in Canada, but also doing some linked work on bird feathers in Chile) are also doing some interesting work in this field and you might want to link to them. They may also have some young vets interested in helping you. You might also involve the aboriginal community do some citizen science.

Good luck Carolyn

Not sure if this will help but the custers at USGS work on Swallows and collect eggs and chicks to sample for legacy contaminants. See attachments

Another attachment on the custer's work

thanks Carolyn for the info about vets, and James for the papers. I will check them all out. much appreciated

I went to school with a guy that looked for cadmium in salamander livers. I don't know if it was ever publish or where to find the protocol. I think basically they ended up killing the salamander, removing the liver, drying it, grinding it in a mortar and pistil, dissolving what they could, and running flame atomic absorption to determine cadmium concentrations. I don't know if that helps, but hopefully it gives you some ideas and a place to start.

"basically they ended up killing the salamander, removing the liver, drying it, grinding it in a mortar and pistil, dissolving what they could, and running flame atomic absorption to determine cadmium concentrations"

yeap... Our chemists are doing the same, but with fish (respectively, with fish liver)

Hi Keith, several monitoring programs on contaminants across Canada will use eggs (see Weseloh's papers for the Great Lakes, Burgess' papers for Atlantic, Braune's papers for the Arctic, Elliot's papers for the Pacific, Champoux's papers for the St. Lawrence) and they typically look at several metals, legacy and new contaminants so it is a good option if you want to compare with other areas. For mercury, it is important to know that it will bind specifically to proteins and will be very high in feathers (especially the methylmercury form, see Monteiro & Furness http://www.ncbi.nlm.nih.gov/pubmed/11491567), so you won't be able to compare your results with other tissues (e.g., eggs). In terms of feather sampling protocols, there are a lot of papers out there and the important thing to consider is to use the same type of feathers. Different types of feathers may give you very different concentrations (e.g., flight feathers as opposed to body feathers). For examples of protocols in chick feathers in the field, see http://www.bioone.org/doi/pdf/10.1675/063.032.0211, http://www.int-res.com/abstracts/meps/v243/p261-269/ and http://www.sciencedirect.com/science/article/pii/S0025326X99002052.

For COTE specifically, see Nisbet papers (http://www.int-res.com/abstracts/meps/v242/p267-274/) and Burger papers (http://www.ncbi.nlm.nih.gov/pubmed/8161233) for examples. Note that the techniques for washing feathers and digesting them will vary.

Hope this helps

Raph

Thanks all, great info. Raph. Your input is greatly appreciated. I see this as the start of a long term monitoring program for the region, as mercury is expected to continue to rise for many years after flooding, so it would be grea to compare to other studies the internal validity is of most importance.

Happy to help. Forgot to say that if you sample eggs (if you choose that option) early enough, i.e., before mid-incubation, females will likely re-lay, so it is important for conservation purpose if you want to avoid too much impact on the colony.

You should go have a chat with Neil Burgess (Environment Canada, Mt Pearl, NL) if you are at Memorial - he is a great guy and knows a great deals about Hg in birds.

Cheers

Raph

Awesome. Will do

Hi, Keith,

I would like to echo Raph's cautions on collections and techniques affecting mercury values.

We run the Marine Environmental Specimen Bank in the U.S. and have fairly long-running program collecting seabird eggs for banking and inorganic (mainly mercury) and organic contaminant analysis. We would be happy to share protocols with you. The major issue is avoiding contamination during collection and processing. Also if you are thinking about eggs, be aware that there are several studies indicating that contaminants vary with laying order. Birgit Braune at Environment Canada would also be a wonderful resource as she has experience with multiple tissue compartments including feathers.

Thanks Stacy any protocols you could provide would be greatly appreciated. [email protected]. I will contact Birgit

Hello everyone,

I'll take this topic to present to ask you a similiar question but I want to know about oil components. Could you help me?

Mazher Sultana Presidency College, Madras.

I am a toxicologist. I do toxic studies related to fish. I have seen lot of structural variations in organs like, gills, liver, kidney and intestine. I have also observed histo pathological changes in gonads also due to heavy metal toxicity. you can follow the same protocol (AAS).

Contact Keith Grasman, Professor. Keith Grasman [email protected] (616) 526-6024. Office: He does some collection work with these birds on the Great Lakes and I know there is a US - Canadian monitoring progam on the Great Lakes as well and they should be able to provide you with SOPs.

Hi Keith!

I'm a Ph. D. Student from Mexico. Our work is focused in development a monitoring program of pollutants in seabird from some wetlands. In preliminary results, we found that the eggs and adult blood samples are best that dead chicks. The pollutant levels in these samples are greater than in liver and muscle of chicks. However, still unknown the results another samples (feathers and more eggs and plasma samples). The dead chicks were collected after an anormal temperature drop in the region, but the results show than are not the best kind of sample for our work.