SMSG Blog

Expedition blogs and news from the Shallow Marine Surveys Group

Sampling at the Ascension Island fishing competition

By Emily Hancox

The final day for most of the team coincided with the annual fishing competition. We arrived at the pier at 11am, to be met with the first fishermen returning with their fresh catches, and a small crowd of spectators.




[caption id="attachment_985" align="alignleft" width="181"]Fish Comp2 Large yellow-fin tuna

Being saved the effort of catching our own specimens, the team rapidly set up an array of scalpels, knives and forceps to process the variety of fish available. The goal was to collect length, weight, sex and maturity information, and to extract the fish ear bones (otoliths) for ageing purposes. A messy business at times, bystanders watched with interest as the borrowed hacksaw was put to use, sawing open fish heads to reveal the otoliths. A small crowd of children became willing assistants, holding little vials and offering enthusiastic advice as the blood, brains and bones occasionally proved challenging to work with. As the sun swang around to glare upon our previously shaded workspace, onlookers “oohed” and “aahed” as the first of the boats returned with their spoils. Huge tuna, the largest weighing 120kg, were craned on to the pier and winched into position to be weighed. After being professionally butchered and sliced into stunning chunks of meat, the heads were available for us, and the saw was back in action.


Fish Comp IMG_1721


The species available for sampling were diverse, different jacks, dolphin fish, moray eels, and wahoo forming a part of the hooked fish that were brought to the table. Remnants of these, and those that were unwanted were rapidly welcomed by the blackfish in the water below.


As people retired to the Saints Club, samples were packed, gear was cleaned and packed, and preparations were made for our imminent departure.


Thanks to all who were involved!

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Things that go bump in the night

By Judith Brown

To get as complete a species list as possible we need to survey different habitats, different seasons and also during the day and at night. Some species remain well hidden during daylight hours when the plethora of fish predators make leaving the safety of the crack or crevice hazardous. When night arrives the seabed is littered by the sleeping bodies of the black fish and out comes a different array of animals. The striking red reef lobster, the small red scorpionfish, giant stretchy yellow banded sea cucumbers, many species of shrimps are just a few who we don’t see through the day. To quantify the difference in species diversity and abundance the SMSG team prepared for some day night comparison surveys.




[caption id="attachment_979" align="alignleft" width="300"]Q66 A (20) Day Quadrat Day Transect


[caption id="attachment_980" align="alignright" width="300"]Q66 B (20) Night Quadrat Night Transect

The survey method was adapted slightly (to compensate for reduced visibility at night) and involved three transects each 1m x 50m survey all along the rocky reef just off Wigan Pier. During the early afternoon Judith, Paul and Martin conducted the first set of transects – leaving the tape measures in situ with activated glow sticks on each end. As darkness fell the divers returned to the pier – Judith with a dive torch strapped to her head to allow her to count and write. This worked well except for that many small amphipods and worms which were attracted to the light at night meaning she had a constant swarm of critters buzzing around her head for the entire dive. Longspine black sea urchin were the most abundant to count with several hundred on each transect but the most exciting critter was an orange nudibranch – usually only found well hidden under rocks. After an 84 minute dive the team were all happy to return to the dive club to a pot of traditional St Helenian pilau cooked by Elizabeth on the BBQ.




[caption id="attachment_978" align="alignnone" width="300"]Q65-66-67 Macros Associated with Night Transects (6) Red Reef Lobster Reef lobster
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Volunteer Ecological Surveyors

By Sarah and Simon Browning

Simon and I have been volunteer divers with the Shallow Marine Survey Group (SMSG) for the last two years and have been privileged to undertake a number of marine research expeditions within the Falklands.


Last year we joined the SMSG Ascension Island expedition bringing with us a small team of the military divers from the Falklands but this year we are by ourselves as volunteers directly supporting the project, our main role to participate in underwater transact surveys, specimen collecting and underwater photography.


130531Q52 and 53 00620130526-Ascension Is_PSII-U 060


Arriving on 24 May, we landed a few days ahead of the main group to enjoy some leave relaxing on this fabulous island.  We took the opportunity to do a couple of dives to check out the camera and more importantly confirm our fish identification skills ready for surveys! The topside of Ascension is equally fascinating and we enjoyed a couple of beach walks beachcombing and watching the blow hole at North East Bay. The evenings were spent on the beach looking for Green turtles and, even though now at the end of the season, after only a few minutes sitting on the beach we saw three laying - amazing. At the same time we saw hundreds of baby Greens scurrying off in to the sea under a full moon and were also very lucky to witness an eruption – truly spectacular seeing so many tiny juvenile turtles pouring out of the sand.


Our leave was soon over with the arrival of the RMS St Helena bringing Jude, Steve and Elizabeth from St Helena. The project swung into action led by Jude with us all out for an afternoon dive off Wigan Pier checking octopus holes, collecting data from settlement plates and assessing general seasonal changes from last August -September. The whole team was assembled by 1 June and since then we have been busy getting involved in all aspects of the project. So far we have  undertaken a number of transact surveys, completed intertidal surveys, collected a number of specimens, helped process samples, revisited the shrimp pools at Shelly Beach and helped with otolith (fish ear bones used for ageing) removal.


20130526-Ascension Is_PSII Simon-U 129


For Simon and myself this trip has given us such a great opportunity to work with eminent marine biologists and in the field. We are looking forward to the next week diving and exploring the rich marine ecology of Ascension…what new species will we discover?

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Black triggerfish anecdotes

By Dr Martin Collins


It’s great to be back on Ascension and a particular treat to exchange the cold winter waters of the Falklands for the tropical seas surrounding Ascension.


Yesterday morning myself, Stevie Cartwright, Steve Brown, Elizabeth Clingham & Sarah Browning visited a new site off a headland between Comfortless Cove and Long Beach.   We were diving from Caz Yon’s RIB (thanks Caz) and Stevie and I were tasked with taking macro photographs and collecting invertebrate specimens, focusing on species that we had not previously encountered.


We dropped down to 10 m and, as usual, found an abundance of the black triggerfish (Melichthys niger). Our quest was for invertebrates, but as we turned over rocks to expose the cryptic fauna, we were surrounded by clouds of black triggerfish, who were snacking on anything that we exposed.  The black triggerfish are not fussy eaters and whilst I was using my ninja-like skills to capture small, but remarkably agile octopus, I heard a squeal from Stevie, whose ear was being nibbled by a blackfish.  Unfortunately for Stevie the little bit of blood drawn by the first bite only served to attract more black-fish and Steve was quickly surrounded.  Steve initially tried to fend them off, but his ears offered an exposed and tasty treat and he was forced to cover them with his mask strap to avoid further damage.


the Usual Balckfish


The little octopus was less than two cm long, maybe a white-spotted octopus (Octopus macropus), which will be new record for Ascension.  Jude saw an adult white-spotted octopus on a dive last week. The octopus has been preserved and will be sent an expert for a confirmation on its identification.


After the days diving and whilst dinner was cooking on the barbecue, eight of us headed out for a night dive off Wigan Pier, in English Bay.  Night dives on Ascension are fantastic and the contrast between night and day is incredible.  At night the black triggerfish that normally nibble on anything that move are found lying on their sides asleep, allowing all the invertebrates to come out and forage.   On this dive Steve Brown and Paul Brewin saw one of the largest invertebrates, a crayfish, catching and consuming a black-triggerfish.   As usual Paul Brewin described it as “Awesome” – I think he needs a new superlative.


Cray Blackfish


The final highlight of the day was emerging from the night dive on the beach at English Bay to see newly hatched turtles making their way to the sea.  One unfortunate turtle’s journey was abruptly curtailed by a “Sally lightfoot” crab that we spotted with a turtle in its claws, but plenty more made it to the sea – the first stage of their long journey to the feeding grounds off Brazil.

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The Elusive Parrotfish

By Dr Vladimir Laptikhovsky


Most us that have dived in tropical seas have seen parrot fishes. You might have heard them crunching and munching corals before you see them, they are amongst the most common fish in coral reefs all over the World. But not only coral reefs… some species in the genus Sparisoma managed to cross huge oceanic spaces and settled around the small oceanic islands of the Mid-Atlantic ridge, like the Azores. One of them, Sparisoma strigatum, is known to be endemic to Ascension and St. Helena. Around St. Helena, according to Dr Judith Brown, it is a very common species in shallow waters. Occasionally it occurs in groups in rocky areas between 5 and 20 meters depth. Juveniles might be distributed slightly deeper, amongst weed and rubble patches on sand at 15-18 m depth. The species was known around Ascension Island and even pictured on local postage stamp. However, our previous expedition that covered most of shallow waters around this island did not find it. Why are its numbers so low that it is virtually unnoticeable? This SMSG/SAERI expedition of is looking to answer to this question.


Parrotfish


Eventually this mystery species was found, south of Catherine Point where a single specimen was seen and photographed by Steve Brown. It was found together with the white spotted filefish (Cantherhines macrocerus), also recorded on our last trip in August 2012. This was indeed quite an unusual site as it had a remarkable abundance of the endemic Ascension Island wrasse too.


Whitespot Filefish

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Dave John Hunting seaweeds around Ascension
31 August 2013
Great to see underwater photos of this very unusual submarine environment where the ubiquitous black...
Helen Marsh Team Member Stedson Stroud
03 July 2013
Great to hear more about Stedsons work, and how he got started, having met him on Ascension Island l...
Simon Plummer Volunteer Ecological Surveyors
10 June 2013
I can’t stop smiling thinking of what a brilliant time you are having. The fact that I can visualise...
Simon Plummer Black triggerfish anecdotes
10 June 2013
An enjoyable and funny read, thank you steve for making me chuckle.
Simon Plummer Ascension Island fish record
10 June 2013
The photos are brilliant, envious.

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