Marissa McMahan

Marissa McMahan

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Published on Oct 28, 2015

Check out black sea bass in the news!

Black sea bass are currently featured in a six-part series runningin the Portland Press Herald. The series was written by Colin Woodard andfocuses on the impacts of warming water in...

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Published on Aug 06, 2015

Live black sea bass collection!

It was a successful trip collecting live black sea bass in Boston Harbor. A huge thanks to fisherman Kevin Cheung for providing a fishing vessel and his local sea bass expertise! We managed to c...

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Published on Jul 13, 2015

Collecting research participants!

Fourth of July weekend included a quick trip to Beals Island, Maine to collect some tiny research participants! These juvenile lobsters will be used in predator-prey behavioral expe...

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Published on May 20, 2015

Field Season Update

Dear Experiment Backers,Field season is once again upon us, and I wanted to give you all an overview of what I'll be up to in the coming months. This field season will be particularly busy because ...

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Published on Apr 15, 2015

Spring update: Stable Isotope Analysis 101

After collecting black sea bass samples, I bring them to the lab for processing. One of the things I will eventually be doing with these samples is called stable isotope analysis. T...

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Published on Mar 17, 2015

That's one hungry sea bass!

Diet Update:A few weeks ago I was dissecting some frozen sea bass samples left over from last summer, and to my surprise, I found a sea bass that had a crab stuck in its mouth! Appa...

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Published on Feb 03, 2015

Video of black sea bass dissection in one minute!

Hi all!Check out this video (link below) of me performing a sea bass dissection in just one minute! Huge thanks to Andrew and Oscar at Experiment for shooting and editing the video!...

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Published on Dec 03, 2014

It's the final countdown!

Hi everyone!We're down to just 2 days left in what has been a whirlwind 35-day campaign. Once again, I am eternally grateful to all of my wonderful backers. To those of you who have...

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Published on Nov 29, 2014

Added bonus for backers!

This campaign is quickly coming to a close. Only 6 days left! Thanks to all of the generous people who have supported this project, Ihave reached my first goal. However, I still have a long way to ...

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Fascinating subject. Excellent research. Look forward to hearing more as your study progresses.
May 23, 2015
New fish on the block: Ecological implications of black sea bass in the Gulf of Maine
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Marissa, Your updates are most welcome and informative. So impressed with the magnitude and importance of your research. You shine in your field. Thank you!
May 20, 2015
New fish on the block: Ecological implications of black sea bass in the Gulf of Maine
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Great question Bernie! Once an isotope is fixed as organic matter, the characteristics of those molecules will be passed on to consuming organisms. Sometimes the ratio of isotopes passed on will be enriched from one trophic transfer to the next (one trophic transfer would be a crab eating a mussel, a subsequent transfer would be a fish eating a crab, etc.). Carbon isotope ratios are usually enriched by 1% or less, whereas nitrogen isotope ratios are enriched 3-4%. Because the ratio of carbon changes very little as it moves through the food web, it tends to be a better indicator of the source of the carbon. The ratio of nitrogen is enriched relative to diet, and therefore is a better estimate of trophic position - it's basically a way to track the flow of nitrogen through a food web.
Apr 16, 2015
New fish on the block: Ecological implications of black sea bass in the Gulf of Maine
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Hi Phyllis! The project is going great, although a little slow during the winter when I can't be out in the field collecting data. I've had a productive winter dissecting fish in the lab though! I hope to post some new updates in the near future, especially once field season is up and running. Hope all is well and look forward to seeing you this summer! All the best, Marissa
Mar 13, 2015
New fish on the block: Ecological implications of black sea bass in the Gulf of Maine
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