Posts
Kill Switch
Posted by Graeme Lyons , Sunday, 5 April 2026 08:28
I have just got back from a well-needed mini break, something I always do to mark the change between the winter ID and write up period and the start of my field season. A few months back, Nathan Jackson (one of a bunch of incredibly talented young naturalists from Bangor University) invited me a long to a trip he was planning from Bangor to Falmouth. Now I was down there in November where I spent some time with Finley Hutchinson (one of a bunch of incredibly talented young naturalists from the Penryn campus of Exeter University). Furthermore, we coincidentally had a contingent from Hampshire, including John and Tara, as well as my mate Kim from Brighton and loads of other people. We mopped up back in November with just a few of us, so with the dozens of eyes in the rock-pools this time, with very much a focus on nudibranchs, there was no way I was missing this. I could only do four nights though, so have had to suck up getting gripped off by amazing stuff being found before I arrived and (still ongoing) after I left. Yet I cannot complain, this was one of the best four days natural history of my life.
Yet the opening image of this post is of two bull Killer Whales (this is one of Nathan's shots). Apparently, they are slightly larger than the largest nudibranch, this was quite possibly one of the most magical and unexpected moments of my life. So how on Earth did we go from turning rocks for sea slugs to running after Orcas along the cliffs like feral children? You'll have to wait...
Day 1. Karen and I left Brighton at 3.55 am to arrive at Falmouth for 10.00 am, comfortably making the first low tide. Finley suggested some new areas at Tunnel Beach and that place was really productive. So I think we collectively saw at least 20 species of nudibranch on this trip, I saw 19 I think and eight of those were lifers. First up, check out this little nerd! Rostanga rubra is such a cute little dude, it's the only only nudibranch to wear corrective lenses over its rhinophores.
My second nudibranch lifer of the day is also another common one down there but I think its my favourite. As pure white as the driven snow, with the weirdest shaped chocolate-coloured rhinophores. The best thing about this is that it is perfectly camouflaged to hide among the pure-white nudibranch eggs that it specialises in feeding on. Favorinus branchialis. See if you can spot this one hiding in the eggs. What I love about this one, is that it makes finding nudibranch eggs even more exciting. I really fancy some shredded coconut after looking at these pictures.
But Rainbow Sea Slug Babakina anadoni was playing hard to get, then I stumbled on this huge animal. Not the first time I have seen one but it's such a wonderful moment every time you turn a rock and see this. Even better though is showing it to people for the first time, it's such a privilege to be able to do that with wildlife this spectacular.
Probably the best sea slug I found I didn't even photograph, Okenia nodosa is scarce at Falmouth (but really common at my nearest patch). Next up, a long overdue lifer for me under the first rock Cameron Wilkins turned over. Jorruna tomentosa, I didn't get a good photo but there were quite a few of these rather plain but attractive little dorids about.
Karen spotted her own Limacia clavigera, they are really common down there.
Nathan walked right up to this stalked jellyfish, which was a lifer for me (I have only seen three species, all of which I saw at Falmouth in the first two days of this trip). This one is Halycistus octoradiatus with those odd tubercles at the base of the stubby tentacles. It's a rather sickly green colour too.
And this snail was quite the looker, we had one here and one at Silver Steps the following day. Raphitoma purpurea, yet another lifer.
The weather was glorious on that first day, so there was some chance for some spidering in Falmouth after, Ero aphana was popular and I managed three year ticks. I got sunburnt on the last day of March!
Now, I am well known for being pretty intense and having a lot of energy, but I had to look after my health on this trip and not start my field season in a state. So I only managed to go out on one night time session, the first night. After four hours sleep I was back out of the hotel wandering around the rocks but I was feeling really rough, so didn't make it all night. It was magic though!
And it wasn't long before Nathan made the kind of sounds that can only mean he'd found something exciting. Now I only managed a rubbish shot in a pot, but this is Calma gobioophaga. This nudibranch only feeds on the eggs of gobies, and apparently the eyes of the tiny fish it eats on the eggs can be spotted in their serrata! Yolanda told me about these last year, so this was an exciting find for everyone!
Day 2 (technically). It's just gone midnight now and Nathan spotted these two Atalodoris pusilla sitting next to each other like a pair of slippers. My fifth nudi lifer of the trip.
Talk about starting with a bang! By this point though it feels like Day 4 when it's still only Day 2! We head to Silver Steps. Finley found a big patch of nudi eggs covered in Favorinus, and there was a speedy Facelina annulicornis there too. We picked this up last November but this is the first time I have got a half-decent shot if it. What an absolute stunner that is!
We had two more staked jellyfish in the same gully, neither were new for me but I love seeing these. Calvadosia cruxmelitensis.
And Calvadosia campanulata.
I found another Babakina. At least three were found that morning.
Now bear in mind it's April fool's day. I was just taking some shots of this when Finley yells that there is a report of Orca's swimming past the Lizard! It took us about ten minutes to realise the weight of what was happening before galavanising into action - just as Tylan had arrived, to see a wave of be-wadered rock-poolers running towards him. No, straight past him, to their cars! We all piled down to the Lizard (Tylan too) and about an hour later, this happened...
I love this shot of Yolanda's with the cliffs in too! Here are a couple of Nathan's. You could see the white behind the dorsal fin, even through my rubbish binoculars.
It was Finley who got onto them really quickly though, like in less than 5 minutes. Finley followed by myself likely to be the first people to see Orca and Rainbow Sea Slug in the same hour. Here's the prostrate form of me creating my own mud bath in excitement. Tylan here is wondering if its possible to suction sample an Orca.
Day 3. This was quite possibly my favorite day. Helford Passage from 11.00 am to 2.00 pm on the sandy Eel-grass and then Kynance Cove with Tylan and Paul from 3.00 pm to 6.00 pm.
Auger Shells, three species of pipefish, cockles in numbers but it was this huge egg mass that got me excited, as I had never seen anything like it before. It turns out to be the egg mass of Pleurobranchus membranaceus. They had an adult after I left which I missed but the eggs were cool enough!
And I had a few of these darker ones with mottled serrata. They really are quite stunning.
Then Yolanda caught a Nursehound with her bare hands! I have only ever seen the egg cases, so chuffed to see an adult.
And Finley showing three species together. Acanthocardia paucicostata (the small one - which I had there new to Cornwall in November). Spiny Cockle Acanthocardia aculeata on the right and Rough Cockle Acanthocardia tuberculata on the left. It's 2.00 pm and my alarm rings, so I have to leave everyone to head to Kynance!
It was just the three of us (Tylen Berry, Paul Gainey and myself). The weather was glorious. Now I am really here to year list spiders, bugs and rare plants! I ticked off Hairy Greenweed and Cornish Heath soon enough, along with Lousewort and Heath Milkwort. Choughs were everywhere.
Tylan found most of the rare spiders instantly! Gnaphosa occidentalis under the first rock. I spotted an adult male Aelurillus v-insignitis. Euophrys herbigradus was in every suction!
We scrambled down the slope for a few ants. Ponera testacea somehow appeared in one of Tylan's pots. Lasaeola prona ticked for the year when Ty found two rather odd looking crabbies. Now I see Ozyptila claveata all the time on the chalk, so I was sure they were not that. Ty sees Ozyptila blackwalli enough to know it wasn't that either. Could this be Ozyptila scabricula?! Indeed it was! Check out these perfect little gargoyles. Ty found another male too, these being the first in Cornwall since 1968 and an entirely new hectad. Mad for a site he works really hard, and it just goes to show no matter how hard you work a site, there are still treasures to be found! This is my 564th spider in the British Isles. I was not expecting a spider lifer this week.
Day 4: Winding now, one final trip to Tunnel Beach produced much of the same, but Finley was on fire with his small crustaceans, including pointing Vicky Barlow to search the mouth of a huge Spiny Spider Crab for a host-specific thing called Isaea montagui, what a bizarre creature.
