Irish Marine Life
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The Best and Worst of Marine Life
Image credit: The Mayo News 2010
We paint quite the blissful picture of marine life here; considerate crustaceans pausing for examination by curious biologists, obliging fish waiting patiently for a snorkeller to enter the shallows and so on.
For some, however, the abiding marine life moment of Summer 2010 will be a sore memory, as they never imagined a trip to the beach on a glorious day could conclude so very ingloriously – sitting by the lifeguard’s hut with a swollen red foot in a bucket of boiling water.
That’s the proverbial insult to the injury of a weever fish sting, the incidence of which rises in August each year, not because there are more of them, rather because there are more of us.
The weever fish (Echiichthys vipera) spends most of its time buried in the sand around the low tide mark, and unfortunately for us, with its poisonous dorsal fin pointing straight up waiting for a shrimp or small fish – or an unintended surfer, body-boarder or swimmer.
Weever fish stings are more likely at spring tides, when lower water allows us to be further down the beach in weever territory.
The venom has only taken one person so far, and that was a long time ago in England. It’s still quite painful though and requires immediate immersion in water as hot as can be tolerated to breakdown the proteins in the venom, and kill the pain.
Things can go the other way at the beach of course and when it’s good, wildlife-wise, it can be very good. Like last night, we were out surfing when we got a lot more than the good waves that had been promised. A half hour before sunset, a pod of bottlenose dolphins stole quietly from the deep into the waters around us, gently breaking the surface to announce their presence and eventually, after 20 minutes or so, joining in with the wave-riding. This they do rather well, as they effortlessly match the waves’ speed with their powerful tail propulsion and authority of movement.
Why they do this is another question. They are animals with deeply complex social and intelligent workings which need stimulation (the humans who indulge in this activity might argue the same), so a likely answer would be found somewhere there.
They come inshore year-round but late August and early September always seem to be a good time to share a wave with them at a Mayo beach.
Sea Spuds
Image © JP Tiernan 2010
‘’I found something on the beach the other day, maybe you’d know what it is? ´´ is something I hear a lot, especially in these, the longer days of the year. This week’s query grabbed me more than most would however, primarily as it was presented more elegantly than most would bother. In a box which once held an expensive wine glass and wrapped so carefully in the soft foam which once cosseted that same delicate crystal were seven gleaming nuggets, brilliantly white and alluringly fragile.
´´Urchin shells’’ I said, but puzzled at how white they had been bleached. Could they really have caught that much sun, and all the while lying intact on a windy West Mayo shore? ‘’Domestos’’ she confessed, explaining that she thought they would improve a shelf or windowsill somewhere in her new house. They probably will, especially as they are not found so much around here, certainly less than the whelks, limpets and clamshells which line mantle pieces and bring beach thoughts to living rooms around Ireland.
About the size and shape of a small spud, the Sea Potato (as it is called in the West of Ireland) or Heart Urchin (as it is called by the rest of the world) is an echinoderm, that group of species which, in basic terms, are all quite round such as starfish, sea cucumbers and sand dollars. The animal lives inside the exceptionally thin shell which contains an elaborate configuration of tiny holes, allowing soft spines to stick out and defend against predators. Other urchins, like the once abundant but now overfished purple urchin, live on rocks and graze algae but the sea potato spends its life covered in soft sand, feeding on detritus.
How did this sand dwelling subtidal species come then, in numbers, to meet such an elegant end as a polished ornament at the hands of a beach walker? The sea potato breeds in summer and it is at this time that large numbers of juveniles are found on the sediment surface. An out of season large swell, which we received last week, would be their certain shoreward transporter. Or, more likely, they could have recently taken up an unwelcome residence in a lobster pot, as they are reputed to do, and found themselves subsequently evicted by a fisherman whose windowsill and mantelpiece collections are already quite complete.
This article appeared in The Mayo News 3/8/2010
Snorkelling Season in Mayo!
Image © J.P Tiernan 2010
Our foreign service continues this week, in the form of shallow water surveys, employing those most rudimentary tools of the marine scientist: snorkel, mask, fins and a good attitude. Which is what we would be most likely doing were we in Mayo this week, given that we are into the last weeks of July and early weeks of August. Settled seas, good visibility, warm(er) waters and friends on holidays mean these weeks of the year are prime snorkelling season.
Better wetsuit technology in recent years means now more affordable and reliable warmth in our temperate waters, which will top off at – a still quite cool – 16° Celsius or so, sometime in September. These key pieces of equipment, which were once heavy, expensive and came in limited sizes, are now light, reasonably priced and widely available for everyone from toddlers to xxl folk.
More and more people, thus, are taking their first look below and seeing for themselves the occasional wildlife treasures that they didn’t know could be found in Mayo, such as the cuckoo wrasse (pictured). Family visits to Mayo’s 11 blue flag beaches now often deviate to the fringes of the strand where rock-pools and shallow water rocky habitats draw kids and adults hopeful for a glimpse of an iascán, darting nervously in between rocks, or more ambitiously in deeper locations perhaps, a pollack, or a dogfish snoozing on the bottom.
Shores which are too sheltered such as around Carraholly, Newport and Bunnacurry, Achill aren’t much good for snorkelling as their waters are often sedimented giving poor visibility and subject to strong tidal flows. More exposed locations such as Old Head, Keem, Inisturk and Clare Island are perfect, providing there is not much swell present. On extremely calm days, a lone rock in shallow water at beaches such as Carramore, Doughmakone, Mulranny, Keel and Elly Bay is a perfect introduction to Mayo marine life. Rock pools left by the tide are perfect for the youngest of snorkellers.
Important to remember is that snorkelling zones are usually well outside the limits of lifeguard protection; snorkellers with 20 years of experience always tell someone on shore before they go and never go alone; nobody should. For those looking at rockpool life, a tide table is necessary as is careful consideration of the following phrase, which those living by any West of Ireland shore will have heard countless times – ‘tide waits for no man’.
This article appeared in The Mayo News 20/07/2010
Vegetarian Ninjas and Irish Leatherbacks
Image credit: L. Duignan 2010
Like some of our larger and finer marine species at home, the Pacific green turtle is vegetarian, or more accurately, turns so upon reaching its teenage years. It also becomes increasingly more relaxed, almost indifferent, at this later stage of its life. Whether the two are related is doubtful, but in any case it an easy animal to spend time with, facing adversities such as camera brandishing marine biologists with an almost lethargic nonchalance.
Here, the might of the Ecuadorian National Park authorities is proving greater than any Pacific swell in keeping our ship in port. We should be at sea now, carrying out surveys of threatened marine algae species, but permits and an endless tide of bureaucracy which serves no-one, least of all conservation science, means we wait.
It’s not a bad place to wait however, and daily trips underwater to brush up on our identification skills of the local species and carry out pilot surveys keep us occupied and photo-full. It’s not too far from our project brief either, to spend time taking shots of and writing about these attractive reptiles. They gather in inshore bays in these islands to reproduce and be one of the more appealing grazers of the threatened algae that we study. Everyone likes turtles, so grant applications and funding requests for studies of ‘boring’ species such as seaweeds invariably feature any link that can be made to an animal that once only appeared on our screens and in our mindsets after the adjectives ‘teenage mutant ninja’.
As might be guessed from its name, we won’t be seeing the Pacific green ninja turtle vegging out a Mayo bay anytime soon. On the other hand, a turtle which is facing extinction over here in the Pacific has been increasingly shown to be more than just a casual visitor to Irish waters. Leatherback turtles were always thought of as wayward drifters to Irish, and very frequently Mayo, inshore territory. It has become increasingly realised however that the number of turtles and frequency of sightings means we should start thinking of them more as one of our own species; a semi-resident migrant to Ireland rather than a lost traveller.
The same logic doesn’t apply to humans however and strict immigration laws mean we have to be out of here in a matter of weeks. Leatherbacks aren’t as easily encountered in Ireland, usually just sporadically seen by fishermen far from land. But it would make an interesting challenge for the rest of summer 2010; swim with a turtle in our own back yard.
This article was published in the July 6th edition of The Mayo News
Tuna´s end
An excellent article in The New York Times about Bluefin tuna and global fishing considerations:
http://www.nytimes.com/2010/06/27/magazine/27Tuna-t.html?pagewanted=1
The Year of the Shark
Image credit: Mayonews.ie
2010 is truly the year of the Basking Shark. Back in March we mentioned how it was looking good; media exposure and renewed public interest meant their numbers were on the up, both in the sea and on our TV and laptop screens. And it seems very much the numbers game at times –with reports last weekend of 100 taggings off Donegal, and unprecedented sightings of groups of 6, 7 and 8 at a time in Cork and the almost daily sightings from Achill.
There, on a sea barely rippled by the breeze of the first sun drenched weekend of the year, we forgot about records and statistics and settled for the unforgettable intimacy of one Liabhán Mór. They never grew to fear the small boats and curraghs of Achill much to their detriment once upon a time, and so it was easy to slip into the water, camera in hand, when one presented itself at our bow outside Dooagh.
The shaky footage is enjoying a good afterlife on Youtube, where people see a monster emerge slowly out of the dark water and feel the effortless thrust of an almighty and improbably huge tailfin sideswipe the screen as a graceful giant turns away from the camera and swims back to the deep.
The curragh which ferried us home full of talk of the shark and animated speculations to its size (10 to 12 foot? 12 to 15?) was originally destined that afternoon for mackerel. It didn’t take long to complete that task, the first line that went down outside Keem brought up enough for that evening’s indulgence. Mackerel are advocated for by nutritionists for their oil which is rich in Omega-3 acids, preventers of two of the West of Ireland’s biggest scourges: heart disease and colon cancer. Locals, however, don’t get too excited by these early season mackerel. They know that fish caught later in the summer and early autumn are oilier and besides the health benefits, better received taste-wise on the pan or the barbeque.
The science behind this is fairly simple; a winter of reduced feeding, the energy associated with moving to spawning grounds and the act of spawning itself deplete their oil reserves and it is not until June when feeding on crustaceans and juvenile fish resumes around the bays and headlands of Mayo that oil content is restored. Early season and oil-less they might have been, but they tasted good, raw and dipped in soy sauce ‘sashimi’ style, when comparing shark stories later on that evening.
Extra-Terrestrial and Inter-Tidal
I was jealous of the divers slipping bath-like into the water 2 hours before sunset on a long evening last week. The sea in May is as cold as any day in December but the air was warm, the sun was still warm and the water looked warm and quietly receptive. Returning home from a surf mission up north, and without snorkelling equipment we were bound pitifully to the shore to watch their bubbles rise to the surface while they watched whatever was hiding behind fronds of kelp 20 metres below. They were SCUBA Divers, diving with tanks, regulators, rules and buddy systems. SCUBA is fun and useful for when serious research has to be done underwater but on this evening all I wanted was a mask and fins and the simple liberation of free-diving.
An hour later, crouched with camera, I had forgotten about the divers and the deep and renewed my enthusiasm for the shore. I couldn’t get enough pictures of the most colourful rock-pool I’ve ever seen; 2 feet square and a humble 2 inches deep, it was populated by a sea of life. Green, pinkish red and brown seaweeds grew like decorative installations beside evenly spaced peach yellow limpets covered pimple like by barnacles, all out competed for boldness and exoticness, besides space on my camera’s memory card, by the flamboyantly brilliant orange and maroon Beadlet Anemones.
When Beadlet Anemones are left high and dry by the dropping tide, they withdraw themselves into a slimy brown blob, unattractive and not even hinting at how good a show they can put on when underwater. There, and despite years of looking at these animals, they still appear to me as if they might not belong to an Irish shore. Their tender structures, rich colour and delicate wavering tentacles look like relics of a warmer sea or maybe another planet depending on your imagination.
They wouldn’t just impress me I thought, this rock-pool and those extra terrestrial anemones would probably grab a whole classroom if they could only see them. There’s no entrance fee to the intertidal zone and a teacher looking for an economical 2010 school outing could find it here. The Heritage Council’s highly successful Heritage in Schools Scheme www.heritagecouncil.ie can tell you more about the expert in your area who can advise you where to find a good site and answer the endless questions a living rock-pool such as this will generate. Visits to the intertidal should be made at low spring tides which occur between 11am and 2pm for three or four days twice a month. This year, the 13th to 18th and 27th to 30th of May and the 13th to 16th and 26th to 29th of June will be good dates, tide-wise, to go to the shore.
This article appeared in The Mayo News 11/5/2010 edition
New pics
New photos have been added to the ‘Griangrafanna’ section on the right hand side of the webpage. Some beadlet anenomes were too irresistible in a rockpool at St. John’s Point in Donegal on Wednesday evening – the light and clarity is so good, it looks like an underwater shot – its not!
This particular evening, we were equipment-less as we were returning from a surf mission up north. So a rockpool had to do. I was jealous of the divers slipping into the water a few hours before sunset but warmer water and longer light means there will be lots of snorkeling, diving and freediving in the coming months. Send us your images and stories as always to irishmarinelife@gmail.com
Mayweed
source: algaebase.org
There doesn’t seem anything more random than the casual covering of a Mayo beach with seaweed or ‘wrack’ at any time of the year. To the more abstract mind, it might be attractive, and tone up a stormy grey beach in April with welcome lines of olive yellow and toffee brown; to most though it will struggle to be anything more than a disinterested heaping of the ocean’s leftovers every so often. To the more cynical it might be a bad smelling mess drawing curses and closed windows on summer days when the wind comes out of the west.
To almost nobody however, does it seem like the punctual produce of a methodical ocean. It is utterly predictable too if you live long enough by the tide. Economic surges come and go and coastal populations ebb and flow unsteadily, but the May ´purt´ or ‘Mayweed’ always arrives dutifully and astonishingly faithful to the date of May 1st. The May purt or ‘scotach’ in Connemara, is the old fronds of the kelp Laminaria hyperborea. In late spring the kelp sheds these fronds which are the ‘leaves’ of the plant. In winter, the whole plant including its long stipe is removed as it weakens toward the end of its life cycle and is washed up to be known from then on as sea rods.
Predictable too, is what exactly will be on the shore, depending on the part of the county you are in. On a sheltered shore in Clew Bay or the east side of Achill Island a thin black covering lies at the tide line; crispy to stand on when dry. This is Ascophyllum and Fucus which grow on intertidal rocks in quiet shallow bays and inlets. The Laminaria and other kelps grow in deeper waters and the massive accumulations of Mayweed and searods will be found on an exposed shore which has a wave breaking somewhere close by.
Their former life might have expired some months ago in a forest 30 feet below the surface, but the seaweeds’ afterlife continues to unfold on the shore. Sitting futile they are not. A quick headcount of seaweed flies on a laden shore reveals a billion or so per kilometre, sandhoppers which are miniature shrimp-like crustaceans, are less numerous in the millions. These provide for many seabirds including gulls, oystercatchers and turnstones, who don’t just turn over stones; they also turn pieces of seaweed over to find the crab or sandhopper beneath. Detritus from the kelp dries and blows into the nearby nutrient poor sandy soil aiding plant growth and keeping unstable coastal defences from offering themselves too quickly to the sea. And there is still the odd person, apologising to a billion seaweed flies undoubtedly, who gathers some May purt, beautiful or otherwise on its timely arrival, to improve a potato patch.
Brent Geese
A (gaggle?) of Brent Geese stalk the dropping tide at Salthill on a Friday Evening. They are looking for, surprisingly, Zostera, which is a sea-grass or Ulva, which is green algae. They also eat terrestrial grasses.
Look for more information at The Irish Brent Goose Research Group
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