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Every fortnight (or so we hope) we feature a seagrass meadow from around the world. This week, Rosemary Mc Closkey writes about her field site in Porth Dinllaen in North Wales. Rosemary is currently a Masters student at Swansea University and she is studying juvenile fish populations in Zostera marina meadows. 

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Photos and text by Rosemary Mc Closkey

I am a student from Swansea University and I am currently undertaking a month of field work for my Master’s thesis, where I am studying juvenile fish populations in a Zostera marina seagrass meadow in Porth Dinllaen on the Llŷn peninsula, North Wales. My data collection has been carried out alongside and with the support of an on-going collaborative project between SEACAMS and the National Trust here in Wales.

Seagrass bed at Porth Dinllaen on low water

I first visited the site with SEACAMS at the end of April this year to assist with their fish monitoring work and to assess some scarring of the bed caused by moorings in the bay. This also allowed me to get the ‘lay of the land’ so to speak, and to design the methodology for my project. I joined SEACAMS once more in June to carry out more work and to run trials on some small fish traps designed to catch shrimp and small fish. Unfortunately these yielded very little success and as I had yet to visit this site on the low spring tides, I was keen to return for an extended period so I could get a real feel for the site and to adjust my method.  Myself and a field assistant returned to Porth Dinllaen at the start of August with a smaller, lighter seine net with a finer mesh than that which I had used with SEACAMS in April and June. These nets seem to be working successfully and selecting the age/size classes that I wanted.

My research thus far is focused on assessing sites of varying complexity and heterogeneity within the meadow in order to elucidate whether small-scale variations within the bed affects species assemblages. During the 1st week of August, low water on spring tide caused the bed to become exposed, thus allowing some assistants and myself to carry out a habitat assessment.

Carrying out habitat assessment on the Z. marina bed

Plots of 36m2 were assessed and permanently marked out using marker pegs and GPS. Detailed photographs were also taken. I was initially skeptical as to whether or not the heavy duty orange pegs I had used to mark out the plots would last, but I was pleasantly surprised to see most of them have. They have proven very useful for relocating each plot. The main working hazard in that respect has been young kids stealing them for their sandcastles!

I have fished within each of the plots using an 8m beach seine net to assess the dominant species and size classes of juvenile fish. Initially I wasn’t sure whether I would catch the same species that were caught in the much larger seine net. I have found that I am catching all the same species as before, however the majority are juveniles, small fish and shrimps. The larger, fast moving finfish and bigger predators seem to evade the smaller net! The majority of the fish caught were wrasses, gobies, dragonets, sea scorpions, plaice, sticklebacks and pollack. We have also caught the slightly more elusive species such as little cuttlefish and pipefish.

Greater pipefish (Syngnathus acus). One of the many beautiful creatures in the Porth Dinllaen seagrass bed.

I plan to stay one more week at this beautiful location to collect some more fishing data. Getting access to the site for this length of time has been a real joy and I have been very fortunate to be able to carry out extended field work of this nature for my masters project. I look forward to returning to Swansea in order to write up my results and my thesis.

For more information on The National Trust: http://www.nationaltrust.org.uk/
For more information on SEACAMS: http://www.swan.ac.uk/seacams/

Giuseppe pens his thoughts on the Mediterranean Seagrass Workshop in Morocco.

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Every three years, I tell myself “this is the last time”, and then every time I change my mind. I have been involved in the organisation of three Mediterranean Seagrass Workshops (MSW), and the effort and time dedication are worthwhile every time. On May 24, I got on a plane and soon after touched down for the first time in Morocco. True enough, conferences always take us to new places, meet new people, experience new cultures. After a couple of days in a confusing, overwhelming and crowded Marrakech, we got on a bus to Essaouira, where the MSW would be held. The road to Marrakech is pulverous, but with stunning landscapes, changing from the arid land of central Morocco to the olive trees and the green pastures of the Atlantic coastline. The landscape is intermittent with local agriculture fields, some times scattered by grazing goats and sleepy donkeys.

Essaouira: La ville du vent


Essaouira, we would soon discover is “la ville du vent” and for good reason. The wind blows 24/7 over the long stretch of beach, that goes as far as the eye can see. On Monday afternoon (May 28) the participants start trickling in from all directions; this year we have a smaller group than usual, but it’s great to see some of the same people that carry on the legacy, since the first workshop in 2006. Tuesday morning, we are ready to begin. The MSW has always been a great opportunity to maintain a Mediterranean network of seagrass scientists and managers. Only few people from the region attend the global ISBWs and other conferences are often a potpuorri of themes, topics, fields. So we stick we our own seagrass community, at least every once in a while!

Participants greeting each other at the MSW

The other interesting thing, to me at least, is that the MSW is an indicator of Mediterranean seagrass research: the majority of talks generally reflects the trends of what Mediterranean seagrassers are up to, what funding is available and what large processes are underway. I’ll give you examples. In 2009, on the beautiful island of Hvar (in Croatia) a lot of the presented work was focused on the Water Framework Directive, which at that time, the European Union was implementing for the monitoring of European waters. I tell you “monitoring” and “intercalibration” were the key words in those days. This year, no single presentation talked about “intercalibration” – that is clearly done and over with, but climate change is now the word on everyone’s lips.


The fact that conferences take us to amazing places is not just a nice treat. It also gives the opportunity of hosting countries (and their neighboughrs) to increase the representation and participation of their scientists. Given that  European conferences don’t often see a good deal of North African participants, we were particularly happy to see a larger delegation from Morocco, Algeria and Tunisia. Most of us had to dust off our french and start talking. But as usual, these efforts (not just improving language skills) pay off. New collaborations are fostered at each MSW, new partnerships, new ideas and projects. But most importantly new friendships.

Participants of MSW 2012

In pure Mediterranean style, long lunches in front of delicious cous-cous, afternoon chats with posters and swimming pool gatherings make the difference. This is what keeps the community together. And every time, new students, new members, new countries (even the USA and Australia) participate. We were through four days pretty quickly and it was time to get home. Except that the bus back to Marrakech broke and left us stranded in the middle of nowhere under a burning sun. One more story to tell next time. We look forward to the next MSW, each of them has a different flavour and its own character. As they say in Morocco “à la prochaine, inshAllah”.

22nd May is International Day for Biodiversity and the theme for 2012 is Marine Biodiversity. In celebration, we will be featuring a series of articles on seagrass. This week, Elizabeth “Z” Lacey writes about her experiences in the long-term monitoring project in the seagrass beds of South Florida under the direction of Dr. Jim Fourqurean.

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By Elizabeth “Z” Lacey

During my own Ph.D. research for the past five years, I have been doing long-term monitoring of the over 18,000 km2 of seagrass beds in south Florida as part of the ongoing research in the Fourqurean Seagrass Ecosystems Research Lab (http://www2.fiu.edu/~seagrass/).  Seagrass species present include: Manatee grass Syringodium filiforme, Turtle grassThalassia testudinum, Shoal grass Halodule wrightii, Widgeon grass Ruppia maritima, Johnson’s seagrass Halophila johnsonii, Paddle grass H. decipiens and Star grass H. englemanni.  This is a similar list to the one Brooke Landry reported during her vacation in the Bahamas in a previous blog post.  Compared to the 50-60 seagrass species possible, our diversity is relatively low.  With long-term data on seagrass density and nutrient content, Dr. Jim Fourqurean and fellow researchers are able to determine how these seagrass beds are changing over time and what these changes may indicate for overall seagrass bed health.

 FKNMS permanent seagrass monitoring sites (sites located in the Dry Tortugas are not shown).

 Long-term monitoring site Photo by N. Blinick.

 My dive buddy Kirk Gastrich and I complete a seagrass survey at one of the long-term monitoring sites.  Photo by N. Blinick.

Changes in seagrass beds will also have important impacts to the diversity of species that use them for habitat, feeding grounds, refuge and as an important corridor between mangrove and coral reef habitats.  While our seagrass diversity may be limited, there are a multitude of important fish, crustacean and other species supported within these ecosystems.  It is estimated that Florida seagrass beds provide ecological services worth over $40 billion US each year (http://www.dep.state.fl.us/coastal/news/articles/2011/1103_Seagrass.htm).  In addition to the photos of stingrays and sea turtles I posted in my other World Seagrass Association blog entry about my work in Akumal, Mexico, there are a wide diversity of animals that can be seen on any given dive in the seagrass beds of South Florida.  But rather than bore you with my prose, why don’t I let the pictures speak 1,000 words (or many thousands when it comes to the number of diverse species supported in tropical seagrass beds!).

 Caribbean Reef Squid (Sepioteuthis sepioidea). Photo by Captain K. Gastrich.

 Barracuda (Sphyraena barracuda) Photo by Z. Lacey

 Grouper, an important commercial species, spotted in the seagrass bed.  Photo by J. Sweatman

 Sea urchin using turtle and manatee grass to camouflage itself in the seagrass bed. Photo by Z. Lacey

 

Octopus inside a pipe positioned in the seagrass bed to hold a channel marker—you never know what you’ll find when you are observant while snorkeling in a seagrass bed! Photo by Z. Lacey

            These photos are just a few of the many, MANY species that can be found in Florida seagrass beds.  On a recent field trip with my Introduction to Marine Biology students at Florida International University, we caught other animals like moray eels, batfish and sea robins!  In honor of today being International Day for Biodiversity, I invite you to get into the water and spend some time in the seagrass beds.  If you aren’t lucky enough to live near some of these magical ecosystems, then on next vacation you have I invite you to head on down to the Florida Keys and enjoy the diversity of life that seagrass beds support.  These are the things that keep me excited about working in marine ecosystems as I prepare to defend my Ph.D. in just a few short weeks!

22nd May is International Day for Biodiversity and the theme for 2012 is Marine Biodiversity. In celebration, we will be featuring a series of articles on seagrass. This week, Brooke Landry writes about her seagrass explorations while on vacation in Freeport on Grand Bahamas Island.
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Photos and text by Brooke Landry

As a dedicated seagrass ranger, I can’t go on vacation anywhere near the ocean without treating my time there as an underwater exploratory mission. Most recently, I visited Freeport on Grand Bahamas Island, where my mother and I foolishly purchased a timeshare several years ago. One of the true pleasures of vacationing in this spot is the exquisite seagrass bed just 40 or so meters off the beach. Owning a timeshare here means that I can do a repeat sampling of sorts and I’m happy to say that I’ve seen very little change in the bed over the past six years.

The bed is composed of what you’d expect in the clear, shallow, oligotrophic waters of the Bahamas. It’s dominated by Thalassia testudinum with Halodule wrightii and Syringodium filiforme filling in some of the gaps. There’s also a good supply of macroalgae, mostly calcareous greens including Halimeda, Penicillus, and Acetabularia. The grass is fairly dense but patchy and although it’s subject to some disturbance from the rent-by-the-hour jet skis, I have seen neither an expansion nor a decline in the grass itself. What I have seen is an increased number of Diadema antillarum (yah!). Although there is very little coral interspersed in this seagrass bed, there are cinderblocks and as it so happens, long-spined sea urchins love to hide in cinderblocks. I’m assuming the blocks at one time secured buoys for the swim net or served as tie-downs for jet skis, but now there are several just randomly abandoned throughout the bed. In fact, I planned to complain to the resort management about cleaning them up until I realized they were serving as urchin refuge.

The beach with seagrass shadow in the background.

Other urchins, mostly West-Indian Sea Eggs, under the mistaken impression that they were invisible because of the dead seagrass, sponges, and random children’s toys attached to their tests, were everywhere in this particular grass bed. Literally, everywhere. It’s an interesting and beautiful sight to see.

On this most recent trip I also spotted a couple of cow-nosed rays swimming peacefully together, just a meter from unsuspecting and oblivious swimmers. This is the kind of thing I generally like to point out to people, but I’ve grown wary of doing so over the years because, as it turns out, not everyone thinks sea critters are as cool as I do. In fact, most people completely freak out at the notion of being in the water with other living things. I’ve seen swimmers go berserk because their feet touched seagrass. Grass!!! Not a spiny urchin or something that could, given the inclination, bite you, but grass! I’m not even kidding. So I chose to let them swim in oblivion and savored the grace of the rays by myself.

In addition to sting rays, octopi, and urchins that are welcome in any healthy seagrass bed in the Bahamas, I saw one not-so-welcome inhabitant: a Lionfish. Having worked with folks down in North Carolina that did extensive research on Lionfish and their invasive destruction of all things pristine, I’ve seen many Lionfish in captivity. I had never actually seen one out in the water though and it took me by surprise. It was hiding in one of the same cinderblocks that the Diadema were using. I had so many mixed feelings when I noticed it – it was almost like seeing a particularly obnoxious celebrity starlet. It was beautiful and I was awestruck, yet I sort of hated it for its indiscriminately destructive behavior. I wanted it to be gone, but really, it couldn’t help that it was born a Lionfish in the wrong place, so I also felt sorry for it. I named her Pandora and tried not to judge her too harshly, because, after all, there is no species on earth more destructive than my own.

ISBW10 is coming!

Website for ISBW10 is up! click here

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