Skip to main content

Our Romance with Meiofauna

Our Romance with Meiofauna

6 students all with a love for the marine environment but maybe not such a love for meiofauna.
Although we are students that are up for the challenge and we are just happy to be working in such a beautiful scenic marine station so we say “Bring on the Meiofauna”.

Copepod from the superfamily Harpacticoidea viewed under the microscope (4x magnification)
Meiofauna live in and on the sediment. They are small invertebrates that require a microscope to be examined. We want to know can they be used as a bioindicator for polluted waters.
The team sit together for some brainstorming, we are all very polite with our suggestions. I don’t know if this is because we are patient people or because it is the first time we met each other. Being in an Erasmus international masters, it is likely that we are pass each other like ships at the night. Lets see if we are all so patient with each other at the end of this summer school.

Various species of meiofauna, macrofauna and phytoplankton from the samples viewed under the microscope (0,67x magnification)
The team in a middle of an intense brain-storming session...many will follow !

Day1, task one - team name; “THE MOB” - Meiofauna Organisms as Bioindicator
We establish a research plan, we are proud with submitting a thesis proposal in such a short time, but perhaps we were too optimistic? We will be studying “Mortality of meiofauna to different pollutant concentrations”. 

Day 2 we received some feedback from the research scientists. The conclusion was that we needed to go back to the drawing board. Never underestimate the power of experience, their advice was taken on board and after some lengthy discussions we have established an in situ and lab based experiments. Now we all agree it's time to start getting our hands dirty or our feet. 

The mudflats- accessing the area

Pilot sampling

Today “The Mob” conducted the first successful pilot sampling of five different sites of interest around the Tjärnö Marine Biological Laboratory. The aim of this pilot study was to find sampling sites rich in meiofauna. The team needs enough meiofauna organisms to conduct their laboratory experiments. Our study examines the use of meiofauna organisms as bioindicators for pollutions of the sea with tourism/human action associated pollutants like gasoline and sunscreen. 

The sampled areas; one site which had large grain size (sandy beach) close to the research station, four more sites, just behind the two small islands in front of the station (sandy but smaller grain size) and the mudflats at low tide in between the islands and the mainland. 

Mudflat in the Tjärnö area between two small islands and the mainland.

To reach these islands a small motorboat was used to bring the team and their equipment to the sites. At the respective sampling sites, handcorers were used to determine the depth of the oxic layer and to find out where the anoxic layer starts. This allowed the samplers to scrape the top layer of the beach or mudflat which contain the desired meiofauna organisms. 

Our core sample shows just the first few millimeters of the sediment is oxic.

Samples of those top layers were then analysed back in the laboratory. During the laboratory survey species composition and densities of organisms were assessed to compare the sites and find out which were the most promising for further sampling campaigns. The first site showed disheartening results and Ilja was losing hope.

Ilja contemplating life
The decision then was on the mudflat site due to the outstanding high amount of species and individuals found there. The separation of specimens was enhanced thanks to our fellow colleague that suggested we use the MgCl2 extraction protocol, this was a turning point for the teams mood and we were again feeling good. 


Sample Site Established.

The perfect spot for sampling the model organisms was found and the actual gathering campaign started to provide enough individuals of our model organism for the laboratory setup. Due to the size of the study, the various tested concentration of the pollutants and the number of replicates a quite high number of individuals was needed.

Alonso was put to work and this silent him for a short time, but his soft mumbling to himself indicated that his brain was still racing.

“How much meiofauna do you need? Best to take the buckets”- we are scared!

We Found Our Guy. 

During the assessment of the sampled sediment in the laboratory, one species prominently stood out of the others and he is conveniently prestained (naturally red). This outstanding coloured and beautiful copepod was by far the most frequent meiofauna organism that could be found. The final identification to a species/genus level has still yet to be done. After various discussions with professionals we came to the conclusion that the species we are dealing with is a copepod from the superfamily Harpacticoidea. We suggest that the species might be a Metis species but this has to be confirmed. 

Metis sp.-  ( this has to be confirmed. )
Metis ignea  ( this has to be confirmed. )

The Experiments

Final planning for the laboratory setup was done. After long and hard discussions within the team and with help by statistics experts the final setup was decided on.
During the end of the day the team came up with a very promising idea for an additional field study. This study could deliver additional informations which would support the investigation of meiofauna organisms as bioindicator. We are excited to see how all of these experiments will unfold and maybe our love for meiofauna will develop.

Stay tuned for the next blog to find out what we did for our experiments….

Blog written by Jan Phillipp Geissel and Justina Givens. Photos by Jan Phillipp Geissel.













Labels:

Comments

Post a Comment

Popular posts from this blog

Goodbye my BRUVver, Goodbye my friend

Just a few hours are left of the summer school, the report is done, presentation complete, video shown (to mixed reviews…philistines). We’ve had an incredible time here in Sweden and have learned a lot, about fish, BRUV devices, and ourselves… One of the many beautiful sunsets of Tjärnö Surprisingly our experiments worked out well, we discovered that the most complex habitats did indeed have the most fish. They like structures and hiding places, but not as much as they like mussels…which is why we managed to actually see them on the video! We watched many clips like this screenshot to count so many fish Thank you for keeping up with Team eFISHency over the past 10 days! We’ve enjoyed every moment (well mostly…), and are really happy with our work! xoxo Gossip Pearl
Post a Comment
Read more

The wet lab odyssey begins

The Hunger Games wouldn’t be as majestic and thrilling if it weren’t for the games being held in Panem, a futuristic city where the wealthiest and wisest of all beings control the rest of the districts and shape the lives of the masses. So how do a bunch of marine biologists relate to all of this? Well, since we are superior beings, we have the control over our Panem, the wet lab. Just like the movie, districts are our holding tanks and high speed trains are water flows cascading towards the hottest district, where all our competitors await for their chance to be the next Katniss. Arduino, a kind of motherboard to which it’s possible to attach a series of different sensors and switches was used to regulate seawater temperature in our world of two districts: the hot and the cold districts. Our main goal was controlling the temperature in the tanks where our shrimp were kept overnight. This was sort of complex as we needed to have warm baths of running seawater at constant temperatur...
Post a Comment
Read more

Sampling Tjärnö Bay

Professor Karim and Lucy after our last deployment, hurray!! Our experiments are finally finished! We were able to deploy BRUV (see our Finding Fish in Tjärnö Bay post for a description :) ) at all of our sampling locations, plus a few bonus ones. We sampled three different habitat types: sandy, muddy/algae, and harbour areas. Map of Tjärnö Bay with our sampling locations At all of our habitats we sampled at a depth of approximately 1.5 meters to assess what animals are typically found in the littoral zone of Tjärnö Bay - the littoral zone is the region of the sea closest to the shoreline. On our final day of sampling we decided to do a few extra deployments at 10 meters to search for species we didn’t find at shallower depths. We’re working on analyzing all our video footage now - stay tuned for an upcoming creature feature post! Justin and Catie setting up the cameras for deployment Since BRUV uses bait to attract fish, we also conducted snorkeling transects at all of ou...
Post a Comment
Read more