World Oceans Day Quiz


Happy World Oceans Day 2016! This year for World Oceans Day (8th June) we have prepared a special World Oceans Day Quiz! Some answers can be found dotted around this blog, with others about topical issues affecting the oceans today. Try the quiz today and test your knowledge of the oceans and its habitats!

Question 1: Why do the oceans appear blue in colour?
because the oceans scatter red light and absorb blue light.
Try again! Hint: If the oceans absorb it than it doesn’t reach our eyes!
because the oceans scatter both red and blue light.
Try again! Hint: If the oceans scatter red light than the oceans would appear red
because the oceans absorb red light and scatter blue light.
Correct! The oceans scatter blue light so they appear blue when the light reaches our eyes! Further more, red light does not reach the deep sea as it is absorbed so many deep sea creatures are red in colour, so they appear black to predators and prey.
Question 2: Where are the largest rhodolith beds in the world found?
South Western Australia.
Abrolhos Shelf in Eastern Brazil.
The Abrolhos Shelf rhodolith beds cover an estimated 21 000 square km area- an area nearly the size of El Salvador! More can be found at the blog post link below.
At the Mouth of the Amazon.
Incorrect, although newly discovered rhodolith beds have been found in this area
  Rhodolith beds (© Rodrigo L. de Moura)
Question 3: Coral bleaching is caused by…
Predatory sea stars such as the crown-of-thorns starfish who eat the coral
changes in conditions causing the coral to expel symbiotic algae from their tissue.
Correct! When corals are stressed by changes in temperature, light or nutrients they expel the symbiotic algae living in their tissue (known as zooxanthellae), turning white.
the presence of symbiotic animals such as worms living in the coral.
This answer is incorrect!
  Coral Bleaching Photograph by XL Catlin Seaview Survey Copyright of National Geographic reproduced for Educational Use only

Continue reading “World Oceans Day Quiz”

GeoHab Conference, Winchester


This year the annual GeoHab international marine habitat mapping conference took place in Winchester, UK. This is an annual conference with over 160 people attending from 24 countries, for the first time in England! Organised by my former department of study at the National Oceanography Centre, it had been a long time since I had been back in the South of England. The Monday started with a workshop on Object Based Image Analysis (OBIA). Seabed classification methods can be based on classifying pixels, whereas these newer OBIA methods are based on classifying a group of similar pixels or “objects” on the seafloor. The conference began on the Tuesday with the key note speaker Dr. Larry Mayer of Center for Coastal & Ocean Mapping/Joint Hydrographic Center. The first session was on “Technological Advances in Habitat Mapping” with presentations on how new hydrographic surveying techniques can be used for habitat mapping. A poster session took place where one minute oral snapshots of posters were given. The following session on “Coastal and shallow water habitats” discussed environments such as tidal inlets, seagrass beds and mangroves and then “Shelf and deep-sea habitats” had rhodolith beds, shelf breaks, deep sea corals, submarine canyons, mud volcanoes and cold seeps. “National mapping programs” session then discussed important issues regarding the seabed mapping programs internationally and within the UK. The following session on “Anthropogenic and natural disturbance effects” then looked at man’s and nature’s impacts on benthic habitat and “Role of oceanography in habitat mapping” looked at the physical processes driving habitat distribution. This was for me one of the most interesting sessions. Following this, was very pleased to introduce a special lunchtime screening of my full one hour documentary- “Maerl:A Rare Seabed Habitat.” Being a firm believer in science communication, marine science documentaries can serve to educate, inform and transform the science and are useful tools for stakeholder management. It was great to be able to share our team’s work with scientists and educators internationally and even had one request to translate into Swedish! The final session was on “Development of standards for classification, confidence and assessment of habitat maps“- an important session to conclude on new methods to quantifying the uncertainty of the habitat map.  The conference concluded with thanking the organising committee and preparing for Geohab next year in Halifax, Canada. Overall, it was my first GeoHab in ten years and I was so inspired by the dedication of the GeoHab community – at home and abroad.

Admiral Nelson at the Naval Museum, Portsmouth Historic Dockyard

Seabed Habitats Blog Carnival- Happy World Oceans Day!

Happy World Ocean’s Day to you! To celebrate this year, we are hosting our Seabed Habitats Blog Carnival especially for World Ocean’s Day!!! Today on the 8th of June, people around our planet Earth celebrate and honour the ocean, which links us all. Hence, here is the anthology of posts nominated or selected for you to enjoy today from a diverse range of bloggers!

Lophelia pertusa and Eunice norvegica-_Solvin_Zankl_LRLove between coral and worm NIOZ News. A couple of years ago, I went on a cold water corals cruise to help a fellow PhD candidate Anna Rengstorf with her data acquisition aboard the Celtic Explorer in the North East Atlantic as part of the CoralFISH project. During this trip, during a coral sampling exercise, we came across, to my amazement, Eunice norvegica, the worm that lives inside the coral, and saw first-hand the love between the coral and the worm! “The relationship between a cold-water coral and a worm is beneficial for both partners involved,” Christina Mueller, NIOZ.

Common sun star, MARLINMarine Invertebrates This wonderful blog introduces us to all the major phyla of invertebrates in simple language. The most common marine invertebrates are sponges, cnidarians (coral, anemones, hydozoans and jelly fish), marine worms, lophophorates (bryozoans), mollusks (oysters, chitons, clams, snails, slugs, octopus, and squid), arthropods (spiders, lobsters, crabs, barnacles, and shrimp), echinoderms (with five-point radial symmetry) and the hemichordates (our closest invertebrate relatives!).

manta raysManta Madness- a world famous snorkel experience in Kona, Hawaii, Seaing Blue, Natalie Reichenbacher. Manta rays are large eagle rays, which evolved from bottom-dwelling stingrays, eventually developing more wing-like pectoral fins. Night snorkelling in the moon shimmered Pacific Ocean, Natalie tells us of their  flamboyant display with mantas cartwheeling as they feed on the plankton in the water column. They can be seen moving through the water by the wing-like movements of their pectoral fins. Once in a lifetime underwater experience!

Maerl Beds in the Fal Estuary with Harbour crab - Liocarcinus depuratorConservation of maerl habitats Cornwall Wildlife Trust. Maerl beds in the St. Mawes Bank, Fal and Helford Special Area of Conservation (SAC) include the largest maerl beds in south-west UK. Slow-growing over time, maerl beds are amongst the oldest marine plants in Europe, with beds being up to 8000 years old and are a protected seabed habitat in danger of disappearance. Following proposals of dredging, a proposal to make a Marine Conservation Zone (MCZ) was made. Here, sensitive issues are discussed openly and transparently with marine stakeholders to clarify their stance on maerl conservation and strategies to protect maerl for future generations.

Great Scallop - MARLIN

Epifauna and their importance in regeneration of the seabed Arran Coast. The Community of Arran Seabed Trust, Scotland are a community organisation working for the protection and restoration of the marine environment around Arran and the Clyde. This guest post discusses life at the benthos and the recoverability following an anthropogenic disturbance, such as dredging and bottom trawling -fishing activity. Epifauna play a role in reducing the three-dimensional habitat destruction due to dredging.


What lies beneath? NUI Galway Marine Science Blog. This post by marine geomatician and geomorphologist Dr. Garret Duffy, is about the hidden landscape beneath us- the seabed. It explores some of the physical oceanographic processes responsible for shaping the spatial variability of the seabed and its sediment dynamics. It finishes with a specific example of sediment ‘waves’ in Galway Bay, West of Ireland.

RVKearyHydrographic surveying in Dingle Bay INFOMAR Blog, Geological Survey of Ireland (GSI). INFOMAR is a joint venture between the Geological Survey of Ireland and the Marine Institute and is the successor to the Irish National Seabed Survey. As one of the 26 INFOMAR priority bays to survey, Dingle Bay was recently surveyed using the multibeam echosounder, aboard the R.V. Keary, M.V. Cosantóir Bradán and the R.V. Geo. The INFOMAR programme is a leading example of a national seabed mapping initiative and application of technologies to answering scientific questions about the seabed.

Multibeam BackscatterMultibeam Backscatter NOAA Ocean Science. Acoustic Mapping Specialist Will Sautter describes multibeam backscatter as painting a portrait of the seafloor of Grand Reserve of Puerto Rico, to be used for seabed classification. He uses an excellent analogy of the tennis court, with different surfaces of grass, clay, concrete etc bouncing/returning the tennis ball with a different intensity, just like the acoustic signal at the seabed.

sunriseSmart Sea School in the West of Ireland University College Cork and partners.  Marine micropalaeontologist, Margaret Browne writes about her cruise with Prof. Andy Wheeler’s team, to the Moria Mounds, West Porcupine Bank and inner shelf off the West of Ireland as part of the West of Ireland Coring Programme (WICPro). The cruise studied the glacial depositional history and ice sheet limits, using the gravity corer and box corer.


Pheronema sea belt and the muddy deep sea Plymouth University. This blog post introduces the Pheronema carpenteri, the bird’s nest sponge, forms dense aggregations in the deep sea, forming a belt at the Procupine Seabight, North Atlantic. The post also describes neighbouring deep-sea habitats and discusses the importance of deep-sea stewardship. It was lovely to find out about this little documented and rare seabed habitat virtually unknown! Image Crown copyright © 2006, Marlin.


SmartBayOcean observatories ESONET members. An ocean observatory is a a sub-sea networked infrastructure of  sensors to measure the physical, chemical, geological and biological variables in the ocean and seabed. The European Sea Floor Observatory Network (ESONET), with the Procupine/Celtic leg, enhances the long term monitoring capability in geophysics, geotechnics, chemistry, biochemistry, oceanography, biology and fisheries in Europe. Coral-covered carbonate mounds of the Belgica Mound Province, north-eastern Porcupine Seabight are main targets for proposed long-term seafloor observatories.

Mining at Deep Sea Vents – what are the impacts on marine life? Deep Sea Mining Out of Our Depth. Dr. Jon Copley, University of Southampton asks the question – what are the impacts of deep sea mining on the organisms at deep-sea vents? Increasing levels of experimental deep sea mining are being proposed to take place at vent fields. Mineral extraction at deep sea hydrothermal vents has been proposed by mining companies after “seafloor massive sulfide” (SMS) deposits. There has been a surprisingly mixed response from the deep-sea scientific community regarding conservation/exploitation, however it is agreed that as a minimum, effective regulation is essential for deep sea vent mining, if not a complete ban.


Setting Priorities to Conserve Marine Biodiversity Global Partnership for Oceans. This blog post by Conservation International discusses which places globally should be a priority for conservation in the marine environment and how to identify which are the most critical ocean habitats. High diversity – high impact places should be conserved first with analysis of the broad-scale patterns of biodiversity and human impacts. Wonderful initiative towards a global solution to maximise ocean health and to apply in practice.

Success of MPAs depends on these 5 things Conservation International. This blog discusses the reasons behind the success of  Cocos Island, Marine Protected Area (MPA) a revered diving site and ecotourism destination. It explores five features of this MPA, discussed in a new accompanying Nature paper and sustainable management strategies; those being how much fishing is allowed, enforcement levels, how long protection has been in place, area and degree of isolation. (© Conservation International/photo by Sebastian Troëng)


Marine Litter

How Bad is Marine Litter? Marine Science Blogs, Cefas. This blog post from Cefas discusses the source of marine litter and quantifying the impacts of plastics and microplastics on the oceans. It also highlights the importance of scientific research blogging and science communication initiatives to creatively and reliably educate the wider public, especially from scientists of the UK government.


mariner_albatrossPoem for Vayda Seamount Tropics- Illuminating the Deep. To conclude, a beautiful poem about the Vayda Seamount, written by Sarah Robinson, as part of the Tropics (Tracing ocean processes using corals and sediments) cruise. An inspirational poem from the deep!!






Acknowledgements, sincere thanks and most thumbnail image credits go out to the creators of the posts for taking part in this blog carnival. A special thank you especially to Natalie for sharing her phenomenal experience underwater with the Manta rays! Image credit for Conservation of Maerl Habitats is to Ross Bullimore. Posts are in logical order by subject matter. It has been a joy to create this post- would love to hear your views on this Blog Carnival here!! Also, thank you to World Ocean Day organiser for putting up the details of the event on their website. Happy World Oceans Day to you!

Tasmania’s Disappearing Kelp Forests

Giant kelp forests off of south-eastern Tasmania. Forest locations were Fortescue Bay and Munro Bight. As of January 2013, the forest at Fortescue no longer exists. Reasons attributed to the decline of this kelp forest and numerous others along the east coast of Tasmania include: warming waters, increasing occurrence of invasive species and a disruption of the natural food chain due to overfishing. This video is a tribute to the beauty of these forests in the hope that the attention they are finally getting from the government is not too late to prevent their extinction.


Submarine Canyons Guest Post

Submarine canyons are steep-sided submarine valleys cut into the continental slope. They are considered to be the main pathways for sediment transport between the shelf (ca. 200 m depth), and the abyss (reaching depths over 4000 m). Unfortunately, in addition to that sediment, they also tend to funnel our human garbage and pollutants into the deep sea…

Submarine canyons occur worldwide, along all ocean margins. A recent study by Peter Harris and Tanya Whiteway counted at least 5849 of them! This work was based on a global bathymetric dataset of the oceans (ETOPO1) that is reasonably detailed. However, in some places we have much more detailed seabed maps, and we see that the better the maps, the more canyons we find. So there is still a lot to discover in the near future!

Some of the canyons that have been mapped are directly connected to a river system on land (e.g. the Mississippi Canyon or the Congo Canyon). Others do cut right into the shelf, but are not necessarily connected to a river. They may be following the course of a deep-seated fault in the geology (e.g. Nazaré Canyon offshore Portugal), or may catch the currents and sediments at the end of a Bay (e.g. Cap de Creus Canyon in the Mediterranean Sea).

Finally, there are also canyons that do not cut the shelf, but are formed deeper on the continental slope, sometimes as the result of repeated submarine slides cutting upslope into the continental margin sediments (e.g. canyons in the Rockall Trough, NE Atlantic).

Canyons are formed by a combination of the erosive and abrasive forces of sediment flows, and of slope failures such as submarine landslides occurring on the canyon flanks. The first process tends to make canyons deeper, while the second one makes them wider. The origin of the sediment flows could be anything from flooding in the feeding river (bringing a lot of material into the ocean) to the activity of storms on the shelf, which stir up al lot of sediment. Many canyons used to be much more active during the ice-ages, when the sea level was lower than today, and the shoreline with its river mouths was much closer to the shelf edge.

Because of the steep topography and the regular occurrence of erosive currents and submarine landslides, submarine canyons contain habitat types that are often rare along the smoother and more homogeneous continental slope. For example, in some places we find rock outcrops which form a solid anchoring point for a variety of sessile fauna that catch their food through filtering of the passing waters.


Figure 1: Stylasterid coral on the flanks of Whittard Canyon (©National Oceanography Centre, Southampton, UK)

canyon_2Figure 2: Patch of cold-water corals and associated filter-feeder fauna in the Whittard Canyon, Bay of Biscay (©National Oceanography Centre, Southampton, UK)

In addition, the steep shape of the canyon tends to affect local current patterns, often pushing deeper, nutrient-rich waters to the sea surface (so-called ‘upwelling’). Once there, the nutrients stimulate extra primary production or plankton growth, which in turn is the basis for a rich food chain. On the other hand, the occasional downslope sediment flows that transport material from the shelf to the deep sea also bring fresh organic matter from the shallower to the deeper waters. This supports a richer fauna also in the deeper parts of some canyons, compared to the average continental slope.

Overall, canyons are often found to be areas with increased regional biodiversity and increased biological growth. This is a result of all the different habitat types that can be found so closely together and of the specific processes that bring nutrients to the sea surface, and organic matter to the bottom of the canyons. It makes submarine canyons very important locations when considering environmental conservation in the deep sea!

Unfortunately, still far too little is known about submarine canyons, about the exact way those current and sediment transport processes work, and about the enormous variety in biological life forms, species and ecosystems that occur. Again owing to their complex shape, marine research in submarine canyons has always been quite difficult. The steep walls cannot easily be sampled or photographed with traditional, drop-down equipment. It is only since the technological development of deep-water robotic vehicles that we can now slowly begin to ‘look around’ in submarine canyons, and can start to understand how they work.

This sometimes requires researchers to think outside the box and turn well-established methods on their head! Which is exactly what Veerle Huvenne and her colleagues did a few years back in the Whittard Canyon. They used ISIS, a Remotely Operated Vehicle (or ROV) to survey the steep canyon flanks. Instead of deploying the multibeam echosounder (the typical piece of acoustic equipment to make seabed maps) in its traditional down-ward pointing orientation, they placed it in a forward-looking position, and used that to make a series of maps of one of the steep canyon walls. To their surprise, they found that the wall was (a) not just steep, but actually overhanging, which is something you’d never be able to see from the sea surface, and (b) covered with a rich hanging cold-water coral habitat, including corals, sponges, fish, bivalves,…

canyon_3Figure 3: Mapping the steep or overhanging walls of submarine canyons leads to the discovery of rich hanging ecosystems which were entirely unknown until a few years ago! (after Huvenne et al. (2011, PLoS One)).

canyon_4Figure 4: The rich coral ecosystem found on the steep wall of Whittard Canyon, Bay of Biscay (©National Oceanography Centre, Southampton, UK)

Further research into this method is currently ongoing within the CODEMAP project, while other examples of rich hanging deep-sea communities have recently been discovered in different canyons around the world. In terms of marine conservation, these vertical communities could be very important. By grace of their steep morphology, they somehow protect themselves from a lot of the potential human impacts in the deep ocean (at least from trawling fisheries, for example, which nowadays can take place to >1500 m water depth). This way they could act as nursing grounds for several species, and we hope one day they might also provide the larvae needed for the restoration and re-colonisation of other parts of the deep sea that already have been affected by human impacts. Still, steep bathymetry will not protect the rich biodiversity from all the perils caused by human exploitation of the deep ocean – the corals in Whittard Canyon will still feel the effects of ocean acidification, while entangled fishing lines and plastic bags, swept down the canyon by the occasional sediment flows, could be seen in between the coral framework. So it is very important we are careful with those vulnerable marine ecosystems, and that we try to protect them as much as possible.

Here’s an interview with Veerle Huvenne herself, speaking about her work in the Hermione project.



Harris, P., & Whiteway, T. (2011). Global distribution of large submarine canyons: Geomorphic differences between active and passive continental margins Marine Geology, 285 (1-4), 69-86 DOI: 10.1016/j.margeo.2011.05.008

Huvenne VA, Tyler PA, Masson DG, Fisher EH, Hauton C, Hühnerbach V, Le Bas TP, & Wolff GA (2011). A picture on the wall: innovative mapping reveals cold-water coral refuge in submarine canyon. PloS one, 6 (12) PMID: 22194903


Thanks and acknowledgements go out to Dr. Veerle Huvenne of NOC for taking the time to produce this blog post and informing us of this relatively undiscovered seabed habitat.