Showing posts with label Haig Fras SAC & East of Haig Fras MCZ CEND0915. Show all posts
Showing posts with label Haig Fras SAC & East of Haig Fras MCZ CEND0915. Show all posts

Wednesday, 12 August 2015

Onwards to East of Haig Fras

The Cefas Endeavour arrived at East of Haig Fras Marine Conservation Zone (MCZ) at 1am on the 16th May. In contrast to the large bedrock reefs of Haig Fras SCI/cSAC (see blog post), previous surveys of this site have shown that it contains a complex matrix of different sediment types including: rock, sand and mud, as well as coarse and mixed sediments. We planned to carry out 10 minute High Definition (HD) camera tows with still images captured at 30 second intervals and take grab samples using the Hamon grab. At stations that were predicted to be potentially rocky or containing coarse sediments (therefore not suitable for grab deployment) we used the drop camera first to make a visual assessment of the seabed type. It then fell to the scientists to make the final decision as to whether it was a suitable area to deploy the Hamon grab.

                  a)                                                      b)
a) Example of the occasional ‘No Sample’ where not enough sediment was retained to produce an adequate grab sample and b) deploying the Hamon grab on the Cefas Endeavour.   

Despite all of our best efforts in predicting grab-able habitats, sometimes up to three attempts were required to obtain a sample that was adequate for both particle size analysis (a procedure used to determine the size of sediment particles) and infaunal taxonomic analysis (the identification of species living in the seabed).

After long days spent monitoring the video feed from the camera frame, the survey team were happy to get their hands dirty by sieving some sediment!



Day shift lead Simon Pearson checking the sieve for any small marine specimens.

Sieving seemingly endless grab samples requires something of an obsession with marine life; fortunately being on survey is one of the best parts of being a marine scientist! Here are just a few of the species we managed to collect in our samples.

                  a)                                                      b)

                                               c)
a) Nut crab Ebalia spp. b) Red starfish Echinaster sepositus c) Hermit crab Pagurus bernhardus

 Moving away from the obsessions of the slightly eccentric JNCC marine scientists to what this survey hopes to achieve in the broader context. East of Haig Fras was designated as an MCZ in 2013 under the Marine and Coastal Access Act (2009) for three protected features for which the conservation objective is ‘to remain in, or be bought into, favourable condition’. This survey forms part of a longer term monitoring strategy that will assess the change over time of seabed communities in the area, to ensure that the UK continues to work towards conserving these important habitats. Although it seems hard to appreciate (especially when you’re struggling with the Hamon grab at 4am!) each sediment sample collected will be processed, analysed and help to form high quality evidence used to inform environmental decision making at both local and national levels.


A stack of sediment samples prepared for infaunal analysis and an example of the infaunal analysis spreadsheet we will receive when the samples are processed.

It took the survey team a further 10 days to collect the 308 sediment samples and 138 camera tows at East of Haig Fras MCZ but we successfully carried out all of our planned activities within schedule. We even had time left over from contingency planning to return to our first sampling site, Haig Fras SCI/cSAC and re-do some of the camera tows that were initially undertaken in bad weather. Just enough time to sign off with a cheesy day-shift team photograph taken in front of the bridge!


Team photo of day shift. From left in orange overalls (crew): Mike, Mark, Tom and Pete. From left scientists: Charli, Mike (JNCC) Jo, Roi, Jess and Simon (Cefas).










Monday, 27 July 2015

To Haig Fras and beyond!

The RV Cefas Endeavour set sail from Lowestoft at 1am on May 9th carrying 15 bleary-eyed Cefas and JNCC scientists, a hardy crew commanded by the seasoned Captain Terry Byrne and enough teabags to see us through our three-week adventure in the Southern Celtic Sea. The JNCC team consisted of JNCC lead Mike Nelson; experienced monitoring scientist Joe Turner; Siobhan Vye, Haig Fras Site lead; and Charli Mortimer, a member of the Marine Evidence Team.

                                                      
 
Last view of land for three weeks!

The 12-hour steam to our first site provided no time for rest and we were encouraged into action by the lively Captain Terry, who ordered numerous safety drills to put us through our paces and test our sea legs. In chance moments stolen between muster drills, we set to work constructing what would be the nerve centre of our operations: dry lab HQ, a complex labyrinth of technical equipment and cables concocted (and only truly understood) by day-shift lead, Simon Pearson.
    



                 Day-shift lead Simon overseeing survey activities and Captain Terry instructing crew.

Amongst such frenzied activity, the Endeavour motored steadily towards our first sampling site; the dynamic rocky outcrop of Haig Fras located 96km northwest of the Isles of Scilly. Haig Fras Site of Community Importance (SCI) is designated due to the presence of Annex I reef and is the only substantial area of rocky reef in the Celtic Sea beyond the coastal margin. The aim for this survey was to collect data to inform the development of monitoring options for Haig Fras SCI and the rocky habitats that are found at the site. We planned to collect data on benthic fauna and environmental variables that will be used to establish a monitoring time-series that can help us to explain long term spatial and temporal patterns in benthic faunal communities found at Haig Fras SCI.

The reef rises to only 38m below the surface at its highest point, where small patches of algae can be found indicating that there is enough light for photosynthesis to occur. With the surrounding seabed reaching depths of over 100m, these variations of depth and substrate lead to an impressive array of marine species. At shallower points of the shoal, the bedrock is peppered with the Devonshire cup coral Caryophyllia smithii and Jewel anemones Corynactis viridis, whilst at deeper depths, boulders and cobbles support branching and cup sponges and the Ross coral Pentapora fascialis.


Simon takes the lead on photo fixing in dry lab HQ.

After getting off to a slow start with a high swell that complicated the positioning of the drop camera frame above the sea floor, the survey team picked up the pace and managed to complete all 91 planned camera stations in five days. This was partly achieved by the usual competitive rivalry between night shift and day shift and a plentiful supply of chocolate. At each station, the team completed a 200m HD camera transect with still images manually taken every 30 seconds using an additional dedicated stills camera. Haig Fras is a beautiful site and there is always a willing scientist on hand to assume the role of ‘photo fixer’, eager to capture some of the stunning marine biodiversity revealed by the drop camera.
                                                                                                                                                                                                       
                           1)                                                   2)  
  3)                                                     

1) Ross coral Pentapora fascialis and Caryophyllia smithii on reef. 2) Jewel anemones Corynactis viridis, hydroids and patches of pink coralline algae. 3) Spiny lobster Palinurus elephas with jewel anemones Corynactis viridis and encrusting sponges.

With all of our planned sampling stations visited at Haig Fras, we steamed towards East of Haig Fras MCZ our second sampling site for this survey.