Days 10 & 11: Returning Home

Our Sunday morning transects started some 30 nautical miles south of Hook Head, Co. Wexford. This was the second day of our inshore survey and final day of recording for the expedition overall. We targeted major headlands between Hook Head and Roche's Point at the mouth of Cork Harbour. During this survey the cetacean team recorded a single large baleen whale sp. (likely a Fin Whale) very close to shore south-west of Tramore, several groups of Common Dolphins, 2 Harbour Porpoises, as well as one sighting of four of the resident Bottlenose Dolphins in the mouth of Cork Harbour.

The Seabird team had sightings of typical inshore species not seen during the offshore leg of the expedition such as Great Black-backed Gull, Herring Gull, Common Gull, Red-Throated Diver, Shag, Cormorant, Razorbill & Guillemot. Other birds of note included a Manx Shearwater & a 'Blue' Fulmar.

Strong North-westerly winds coming off the mainland made observations difficult at times for both teams. On Saturday night the zooplankton team completed 2 stations but unfortunately didn't connect with the hoped for barrel jellyfish off Rosslare.

Hook Head, Co. Wexford (C) Lilian Lieber

R.V. Celtic Explorer (C) Lilian Lieber

The R.V. Celtic Explorer made her way into Cork Harbour at 18:45 on Sunday evening. The Cetaceans on the Frontier III Survey achieved more than anyone could have hoped for. All three teams collected extremely valuable data which will provide a solid baseline for future monitoring. 

I wish to thank everyone for their support during our expedition. I would also like to especially thank the crew of the R.V. Celtic Explorer for making all of the scientists feel at home and for assisting us in this successful research expedition. To my fellow researchers, it was an absolute pleasure meeting and working with you. I hope to see you all again next year for Cetaceans on the Frontier Expedition IV!  

Chief Scientific Officer: Dr. Joanne O'Brien (right) & 2nd Scientific Officer: Conor Ryan (left) (C) Lilian Lieber

The Cetaceans on the Frontier III Research Team (C) Lilian Lieber 

Basking Shark Scientist: Lilian Lieber

Seabird Team: Jackie Hunt, Derek McLoughlin, Eamonn O'Sullivan and Niall Keogh.

Plankton/Jellyfish Team: Catherine O'Sullivan, Fergal Glynn and John Power.

Cetacean Team: Dr. Joanne O'Brien, Conor Ryan, Clo Collins, Dave Williams, Enda McKeogh, Laurence Manning, Mareike Volkenandt, Róisín Pinfield, Randal Counihan, Paddy O'Dwyer, Suzanne Beck and Teresa Martin. 

~ For the Cetaceans on the Frontier III Survey this is Teresa Martin signing off. ~

The Cetaceans on the Frontier III survey was supported under the Marine Institutes’ competitive ship-time scheme, funded through the Marine Research Sub-programme of the National Development Plan 2007–2013, as part of the Sea Change strategy.

http://www.marine.ie/home/aboutus/newsroom/news/TheRVCelticExplorerseeksoutwhalesdolphins.htm

Day 9: Land Ho!

Last night we made our way inshore to conduct coastal transects targeting major headlands from Cape Clear (West Cork) to Ram Head (Waterford). The first day of this inshore survey provided numerous Common Dolphin sightings for the Cetacean Team.

Common Dolphins Breaching off West Cork (C) Conor Ryan

The Seabird Team noted lower numbers of Gannets, Kittiwakes and Fulmars in this area compared to offshore counts, whilst  6 Manx Shearwaters & 6 Puffins provided further interest. A total of 7 species were added to the expedition list today: Razorbills and Guillemots were both plentiful, Herring Gulls and Great Black-backed Gulls were frequently observed near the vessel, a Red-throated Diver was seen near Galley Head & 2 Common Gulls flew east in the late evening. Of particular note was a 2nd-winter Iceland Gull which circled the R.V. Celtic Explorer for a time. These 'white-winged' gulls are a scarce winter visitor from the Arctic.

2nd-winter Iceland Gull off West Cork (C) Conor Ryan

The Zooplankton team were unable to survey last night partly due to weather conditions but also due to moving to inshore waters for today's survey efforts. However, the team plan to complete 2 stations tonight in hopes of obtaining barrel jellyfish samples.

Knockadoon Head, Co. Cork at sunset (C) Lilian Lieber

Blog post by Teresa Martin



Day 8: Having a Swell Time...

Today we covered our last few transects over the Porcupine Seabight but our observations were hampered by heavy swell. The cetacean team had an early morning sighting of a Minke Whale followed by 2 sightings of Common Dolphins later in the afternoon. The PAM team recorded few vocalisations due to the weather conditions but did manage to obtain some dolphin whistles and click trains. The Bird Team had numerous sightings of Kittiwakes and a few Gannets closest to the shelf's edge as well as a 'Blue' Fulmar and three Great Skuas. The zooplankton team sampled at 4 stations last night with the deepest being 1,700m. The most interesting catch was an ostracod possibly with eggs, a non-swimming pelagic nudibranch, and a decapod zoea.

Listening to Common Dolphin Clicks on PAMGUARD (C) Teresa Martin

Around 15:00 the cetacean and bird outdoor surveys were suspended and resumed in the bridge due to the poor weather conditions, however, the PAM monitoring continued. This reduced survey set-up allowed us to do data entry and make a start on our final report for the Marine Institute due on Monday.

Sea State 6 from the crow's nest (C) Teresa Martin

Swell increasing throughout the afternoon (C) Teresa Martin

Our current position is 83 nautical miles off Fastnet, Ireland and we are now heading into coastal waters. We plan to target all the major headlands between Cape Clear and Ram Head on our coastal transects tomorrow.

Blog done by Teresa Martin

Day 7: Fin Whale Delight

The Cetacean Team hard at work in the Crow's Nest (C) Catherine O'Sullivan

It was a slow morning for the Cetacean Team with very limited sightings, however this drastically changed with a few Common Dolphin sightings, some numbering to 20+ individuals after lunch. A few of these sightings were also acoustically detected by the PAM Team with visible clicks and whistles. Around 15:30, Fin Whale blows were spotted about 2km away from the vessel. These animals were tracked and came within 50m of the bow which displayed 4 individuals, 2 being juveniles. We then broke track and launched the RIB for Photo-ID (Photo Identification) opportunities of the 2nd largest whale in the ocean.

Fin Whale blows (C) Clo Collins

Distinct chevron markings of the Fin Whales (C) Clo Collins

Photo-ID of the Fin Whales (C) Clo Collins

The Seabird Team were busy in the late morning /early afternoon when we were postioned over the shelf edge. There were big numbers of Gannets as well as numerous Fulmars & Kittiwakes, 15 Great Skuas, 2 Puffins & 3 'Blue' Fulmars. Of particular interest were the two new species which were added to the expedition list today, a Sooty Shearwater (Southern Hemisphere breeder but a regular passage migrant to Ireland in later summer/autumn, so a March record is noteworthy) and a 3rd-winter Yellow-legged Gull (a scarce passage migrant & winter visitor from continental Europe).

Sooty Shearwater with a Gannet (C) Lilian Lieber

3rd-winter Yellow-legged Gull (C) Lilian Lieber

The Zooplankton Team covered 3 stations last night to depths of 1,878m. Their findings were very similar to that of previous nights but a new species for the trip, a planktonic nudibranch (clione sp.), also known as a sea slug, was found.

Crew member having a watchful eye on the Zooplankton Team's findings (C) Fergal Glynn

Our current position is 104 nautical miles SW of Fastnet, Ireland and 210 nautical miles due West of Land's End, England. We plan to continue our transects over the shelf edge tomorrow and then start the trek into coastal waters during the night.

Blog done by Teresa Martin

Day 5 & 6: Beaked Whales & Black-browed Albatross

Cetaceans were thin on the ground for most of today and yesterday, however those few sightings that we did have were quite exciting. Towards yesterday evening, we encountered yet another group of Bottlenose Dolphins, about 30 strong with plenty of juveniles. We broke track to attempt some photo IDs from the ship as it was too choppy to safely launch the RIB. These dolphins were associating with 17 Pilot Whales. Unfortunately, they were not very approachable - a recurring theme with bottlenose dolphins in offshore waters it seems. The day finished off nicely with close views of a large whale, most likely a Fin Whale, traveling steadily southward. The increasing swell and fading light made species ID impossible, but Sperm Whale and Humpback were discounted with confidence. 

Today we saw our first probable beaked whale sighting. Conditions were tricky when a large cetacean was seen lob-tailing and breaching amongst some Common Dolphins. The unidentified whale had a creamish-yellow tinge and was far too large to be any of the dolphin species. The sighting was recorded as probable beaked whale. Just 2 hours earlier, the ship broke track to pull alongside a floating whale carcass. On close inspection we were confident that this was a Cuvier's Beaked Whale (and very evidently a male...), sporting fist-sized cluster of stalked barnacles on each tooth. A biopsy dart lashed to a boat hook served as a handy sampling device and a skin sample was taken for genetics. 

Dead Cuvier's beaked whale, 150nm southwest of Ireland. (C) Randal Counihan

Careful maneuvering of the ship allowed us to take a skin sample for genetic analysis (C) Randal Counihan

Bird activity slowed right down today for the most part with very few Gannets & just a steady trickle of Kittiwakes. Small numbers of Great Skuas were still to be found however & 2 Puffins provided further interest. A group of c.60 Fulmars seen scavenging on the Cuvier's Beaked Whale carcass was the largest single total of that species recorded on the trip to date whilst 4 'Blue' birds were also noted throughout the day. 

This increase in Fulmar action might have been the ornithological highlight of the day if it wasn't for the sighting of an immature BLACK-BROWED ALBATROSS that made a pass in front of the bow of the R.V. Celtic Explorer at 11:40am before tearing off West (our position at the time of sighting was approx. 160 nautical miles SW of Mizen Head, along the northern edge of the Goban Spur).

For those of us that were below deck during the initial sighting, some tantalising views were had as it arced high over the horizon at a distance of 1km. Fortunately the bird re-appeared close in (at tremendous speed!) and made another venture right alongside the vessel for all to see at no more than 100m!!! After trailing for a few minutes it departed once again & slinked off into the distance.

Black-browed Albatross is an extremely rare vagrant in the North Atlantic & are normally found cruising around the sub-Antarctic seas. There have only been 14 previous records of this species from Ireland, most of which were seen passing west coast headlands in autumn. Truely a once in a life time experience...unless you're Conor, who has now seen two in this area!

Black-browed Albatross (C) Conor Ryan

Black-browed Albatross (C) Conor Ryan

Black-browed Albatross (C) Conor Ryan

Black-browed Albatross (C) Derek McLoughlin

Conor Ryan & Niall Keogh, happy as...

...Larry, who also saw the Albatross! (C) Joanne O'Brien

Blog post by Conor Ryan & Niall Keogh

Basking Sharks on the Frontier

A basking shark, the second largest shark in the world,  was spotted yesterday just 50m off the Celtic Explorer's bow at 11.30 in the morning (approx. 330km SW of Ireland)! This early in the season, a basking shark sighting this far offshore is rather unusual and provides invaluable data on basking shark distribution patterns. From archival tracking studies we know that basking sharks show extensive migrations across the Northeast Atlantic, thereby frequently moving along the Continental shelf edge. However, being a seasonal visitor to coastal waters around the British and Irish coasts (Irish Sea, Clyde Sea, Hebridean Sea, Celtic Sea and the English Channel)  in late spring, surface sightings are usually not reported until the sharks move closer to shore.

Illustration of basking shark dorsal fin tagging and a non-invasive mucus sampling technique: a scourer attached to an extendable pole. (C) Emmet Johnston, 2010. 

Basking sharks are filter feeders and often surface-feed when plankton is brought up to the upper water column, therefore, a basking shark out here is great news and we are now hoping to come across more sharks to deploy number tags to monitor movement, and to collect mucus scrapings for seascape genomics of this highly mobile shark.

Blog post by Lilian Lieber.

Night 4: Exploring The Deep

Monday night 4 sampling stations were covered by the Plankton Team. The maximum depth that was reached was 2,916m. Similar species to the previous nights were found again including barrel salps (jellies), polychaetes (worms), isopods, amphipods, euphasiids (krill) and chaetognaths (arrow worms).

Plankton sample (C) Lilian Lieber

Plankton sample (C) Lilian Lieber

An interesting CTD (conductivity, temperature, depth, oxygen and fluorescence sensor) profile was generated on Monday night on the final station which covered a depth of 2,916m. The profile showed the differences in surface waters and those at depth. These readings can be used to determine the origin of water masses. A low oxygen signal at 800-1000m corresponded to a peak in salinity values at the same depth. This is most likely the Mediterranean water signal, a water mass which originates in the Mediterranean and exits through the Straits of Gibraltar.

CTD profile at 2,916m

The only surface animals spotted on Monday night were two garfish.


Blog composed by John Power, Catherine O'Sullivan and Fergal Glynn.