13 May 2023

13 May 23 - A Day Trip To St Mary's With ORCA

This was my second Cetacean for ORCA in May 23. The previous week had seen me surveying from Roscoff back to Plymouth. This survey was going to stay within the UK with a day trip to the Isles of Scilly on the Scillonian III. The weather looked mild & sunny with light winds and hopefully calm seas. This turned out to be the case. I drove down in the early hours of the morning & fortunately, I didn't stop until the Long Rock McDonalds on the edge of Penzance. After some food, I planned to head into Penzance. But the car wouldn't start as I had a flat battery. I contacted the team leader for the survey, Mary to let her know & asked if she could pick me up. I knew She was staying near to the Hayle & would be coming right past me. Fortunately, she picked up my phone call & arrived about fifteen minutes later. We were soon parked up in Penzance. Ian, the third member of the team arrived before we needed to join the queue to board the Scillonian III.
The view from the bridge wing
We were allowed onto the bridge, once we were clear of Penzance Harbour. The Scillonian III has a small bridge and there isn't room for us to survey from inside the bridge. However, there is plenty of room on the bridge wings with a walkway in front of the bridge. We had been warned to wear warm & waterproof clothing as we would be exposed to the weather on the crossing. Fortunately, it stayed dry, however, thanks to the wind chill it was far from warm, despite the sun.
Gwennap Head & Porthgwarra Valley
Despite our best efforts, we drew a blank on Cetaceans on the crossing to St Mary's. The Bird highlights were: three Storm-petrels, thirty-three Manx Shearwaters, a few Gannets, some Razorbills & Guillemots and four Puffins. There were a couple of Seals around the Eastern Islands, but they were too far away to do anything other than record them as Seal sp., even though we suspected that Grey Seal was the more likely species. I was focusing on watching for Cetaceans and I didn't have time to do much photography, other than when I was the recorder. We carried on surveying until just before we could see Hugh Town.
The walkway in front of the bridge
Survey over & Mary is enjoying the view of St Mary's
The top end of St Mary's
Telegraph at the top end of St Mary's
We docked just before 12:00 and had about three & a half hours for a shore run. This allowed us to be back on the quay an hour before the Scillonian III's schedule departure to ensure there were no last minute problems getting aboard. We all split up to do different things. My plan started with a walk to Porthcressa Beach in the hope of being able to scan over to St Agnes and Gugh. At high tide, the beach between the two islands is flooded, but at low tide it is possible to walk across to Gugh from St Agnes. There was a Laughing Gull that was hanging around a Lesser Black-backed Gull colony on Gugh.
Porthcressa Bay
I've seen a couple of Laughing Gulls in the UK and many more abroad, so I wasn't fussed enough to jump on an inter-island boat over to St Agnes to try to see it. Plan B was to see if I could see it from Porthcressa Beach. The answer was no: I hadn't bothered taking the telescope with me, but there was too much heat haze anyway. I spoke to a local Birder who did have a scope, but he said the Laughing Gull often dropped into the colony & disappeared out of sight & he hadn't seen it since he had started looking before I arrived.
Porthcressa Bay
Looking into Porthcressa Bay from Peninnis
I wasn't too fussed about hanging around & carried on, over Peninnis Head to look around the Old Town Church & Lower Moors, followed by walking around Porthloo Lane. These are some of my favourite parts of St Mary's. Not surprisingly, there weren't any migrants, but it was good to have a gentle walk around some of my old October haunts from the past.
Moorhen: Chick. Lower Moors, St Mary's
Song Thrush: They are always a favourite for visiting Birders as they are much tamer than elsewhere in the UK
Porthloo Beach
The Scillonian III: A sight that will be familiar to all the Birders who have visited St Mary's
Finally, I ended up back in a Hugh Town cafe to top up the caffeine levels before heading back with plenty of time to meet Mary & Ian on the quayside.
Hugh Town harbour
The inter-island boats return in time to connect with the Scillonian III's departure
We sailed on time and it was a better crossing.
Gugh: This photo was taken from the Scillonian III & Gugh was a fair bit closer that from Porthcressa Bay. But trying to pick out the Laughing Gull would still have been a challenge
My personal highlight on the return crossing, was finding a pod of three Risso's Dolphins heading straight for the Scillonian III, before passing down the port side. Frustratingly, I didn't manage to get any photos. When surveying, the initial priority is to note the vertical distance of the Cetacean from the horizon when it is first seen. We use binoculars which have a vertical graduated marking in the left eyepiece which allows that to be measured. Next you have to measure the angle from 12 o'clock (i.e. the direction the ferry is travelling) to the Cetacean.

These two measurements are useful as they allow the ORCA head office computer to calculate the distance from the ferry to the Cetacean. The maths also needs to know the height of the bridge above sea level (which is a known height for each ferry). The ships heading, speed, position, time, sea state, weather & visibility are also included in the calculations. Finally, the direction of travel and what the Cetacean is doing is also noted. All this information helps the ORCA head office computer to provide an estimate of the number of Cetaceans seen along each of the survey routes and ultimately the population numbers along each ferry route.
Risso's Dolphin: These Risso's Dolphins were photographed from the Plancius on the West African Pelagic between Cape Verde and the Canaries (3 May 18).
Once these measurements have been determined, the next thing is to identify the Cetacean involved. But I had already done that on the first sighting based upon their colouration, size & high dorsal fin. Finally, I could lift the camera to try & get a photo. But I hadn't seen them till they were fairly close, we were closing rapidly on each other and they weren't spending a lot of time on the surface. Think that's enough excuses for the lack of photos. They were only my second UK sighting, although I've also seen then on the Atlantic Odyssey, the West African Pelagic and Banda Sea Cruise.
Manx Shearwater: I saw thirty-three on the crossing to St Mary's and just under three hundred on the return journey
Half an hour later, Ian picked up a very close Minke Whale, but I was the recorder & had to head straight into the bridge to note the time, location, course & speed. Once I had noted them, it had already detected our presence & dived for good. C'est la vie. There were more Manx Shearwaters and a few each of Fulmars, Gannets, Razorbills and Guillemots. But no more Storm-petrels or Puffins. Eventually, we reached Mousehole, before starting the turn into Penzance Bay.
The Wolf Rock Lighthouse off the Cornish coast
Mousehole
St Michaels Mount in Penzance Bay
The second survey of the day was over and to get a relatively calm crossing on the Scillonian III is always a big bonus. It had been a lot of fun & I'm hoping I get selected for another Scillies survey.
Rock Pipit: This Rock Pipit greeted our return from the seawall of Penzance Harbour, while we were waiting to disembark
Fortunately, we managed to jump start the car when Mary dropped me back at it. It was then a straight-forward drive home in one go. I managed to bump start it on the Monday & got the car into the garage. They confirmed that the problem was an end-of-life battery and not anything more serious or expensive like a dying alternator. A new battery & I was back on the road again.