The North Western Waters Atlas is freely available to download from the Marine Institute’s website, www.marine.ie.

Image © JP Tiernan 2011

Bobbing in the waves close to shore one evening a few weeks ago, the almost perfectly spherical and pinkish-coloured visitor from the sea must have looked very out-of-place in the dark-grey frothing surf.
Hard but delicate, hollow inside and adorned with short inoffensive spines all over, it had the decoration of a carefully formed ceramic piece intended for a living room, but had obviously come, intact, from the fierce and uncaring world far out to sea beneath the waves.
Echinus esculentus or the Common Urchin is quite beautiful and arrived to our care as a particularly welcome addition to the ‘I found this on the shore, what is it?’ collection. The urchin is a member of the Echinoderm family, a collection of animals that includes the starfish and the sea cucumber. Radial symmetry is what defines this family, that is, they are all perfectly round with the body radiating out from the centrally-placed mouth.
Our hollow specimen had obviously been at sea for some time, as the fleshy interior, which was once eaten on these coasts (and still is a food of choice in some countries), had almost completely decayed and disappeared. Also gone were the urchin’s long spines, painful and slightly toxic if allowed to pierce skin. Despite the spines’ obvious protective function, the urchins have plenty of predators, including crabs, certain fish and otters.
These predators are important; the urchin itself is an energetic grazer, mowing its way through sizeable quantities of turf-like seaweed on the rocky parts of the ocean floor. Without such predators keeping the population in check, its numbers can explode which can cause devastating damage to seaweed coverage and kelp forests.
These forests provide shelter and nursing sites for many species of fish, thus the potential for widespread ecosystem damage is great. Urchins therefore, are studied carefully by marine ecologists around the world as they find themselves in the unfortunate position of being potential innocent mediators of destructive ecosystem cascade.
So what to do with the ornamental urchin shell? Displaced from its bristly glory on the ocean floor, it surely deserves a place of admiration in a living-room somewhere. An overpoweringly pungent smell is the only obstacle to achieving such a position, therefore 24 or 48 hours in a bucket of bleach is strongly recommended to prime this unusual and beautiful animal from under the sea for a new life indoors.

Imave via The Mayo News

It’s hard to beat grilled mackerel on the West Coast at this point in the year. After a summer of feasting on tiny crustaceans in the bountiful bays of Mayo, the fish’s oil content is at its highest and thus the mackerel is at its tastiest.Always caught with ease, often in remarkable abundance from piers and rocky points on summertime spring tides, it truly is an amazing local marine resource.

Its not just on a small local scale that mackerel delivers; far out to the north and west of Mayo, in boats too big to fit in our harbours, over the deep water spawning grounds where the fish reproduces before coming inshore in summer, mackerel is big business and delivers on a large scale.
What’s truly impressive about this fish is that its stocks, unlike those of other commercially important fish in the North Atlantic such as cod and salmon, have recovered from serious overfishing in the 1960s and are cautiously described as being in a fairly steady state.
Cod, despite a slight recovery this year, have been overfished for decades off the southeast coast of Ireland and are likely heading the way of the Newfoundland cod stocks of the 1990s (total collapse), while nobody really knows what’s happening with salmon, but everyone agrees there are not as many as there used to be.
What is important now is that mackerel stocks are maintained in this way and the boom-and-bust fishing policies of the past are well avoided. In a rare instance of forward thinking by politicians with regard to commercial fishing, Ireland’s minister for Agriculture, Food and the Marine, Simon Coveney, has angrily defended the management of these stocks and has hit out at Iceland and the Faroe Islands. He believes they have set their quotas for catching mackerel too high, thereby threatening stocks of the fish in the North Atlantic once again and consequently, our future fishing industry.
I don’t imagine that the annual summertime deliveries of a bucket of delicious oily mackerel from your local pier or currachs are under threat anytime soon, but its good to know that someone is thinking of the bigger picture so that 30 or 40 years from now, we can still enjoy a freshly grilled and abundantly caught, local resource.

Image © George Karbus

Farraigí na hÉireann (Seas of Ireland) is a new six part Irish Ocean Wildlife series to be broadcast by TG4 from Tuesday September 20th 2011 at 8pm.

Almost two years in production, for the first time on Irish TV, this series takes us on a journey through the beautiful underwater world around Ireland encountering an enormous diversity of wild and colourful creatures. From playful dolphins, giant basking sharks and exotic jellyfish to the recently discovered cold water coral reefs in deep Atlantic waters.

Explaining why our ‘temperate’s seas are so fertile, the crew follow the food chain from plankton right up to whales and dolphins. The sea has always been a great provider for Irish people, from providing food and medicine to the making of fields with seaweed on the previously barren Aran islands.

Image © Sea Fever

They examine the changing nature of our relationship with the sea and it’s creatures from the original subsistence coast folk of 9,000 years ago and the traditions they have handed down, to the ‘super-trawler’ fishing fleet and the current state of our oceans.

Farraigí na hÉireann is the first dedicated Irish ocean wildlife series and was produced entirely in Ireland for TG4 by independent Irish production company Sea Fever Productions from Lahinch in Co. Clare.

The series sets out to bring people on a magical journey through the underwater world around Ireland discovering the abundance of colourful seascapes and wildlife that live there.

Farraigí na hÉireann promo from ken OSullivan on Vimeo.

Chrysaora hysoscella. Image © Wiki Commons

One resembles a big brown Compass, the other, a purple-infused Moon, and for the last two weeks they have been eliciting sudden and sometimes comical involuntary movements from swimmers and surfers at the local beach as their floating armies arrive in pulses and waves from far out in the Atlantic.

The Compass Jellyfish (Chrysaora hysoscella), is the only one of the two which can hurt you. Its long delicate-looking tentacles belie their potent nematocysts (stinging cells) which can launch a mildly painful attack on the not often exposed Irish skin. They are best avoided, and the sting is best neutralised through bathing in seawater and the application of a dry ice-pack.

The Moon Jelly (Aurelia aurita) on the other hand, ranks as one of my favourite marine species. And as such, I’ve been receiving strange and concerned looks in the surf lately as I pick up the Moon Jellies for a closer inspection of their fascinating structure; however my actions are harmless. The Moon Jelly’s nematocysts are too weak to puncture our unprotected pelt and the beautiful purple symmetry of its four internal rings (which are actually gonads), and the surprisingly firm texture of its watery transparent bell-shaped mass lend  it the impression of a most unnatural, alien-like creature, quite unlike any other.

In other parts of the North Atlantic, including the Irish Sea, increasing blooms of jellyfish are a cause for concern as their numbers have been increasing in recent years, seemingly as a response to instable marine ecosystems – now depleted of fish and abundant in what the fish used to eat, zooplankton. Jellyfish in turn, feed on the eggs and larvae of fish and compete for food (zooplankton), further damaging the stocks.

Jellyfish can swim or move, but in a very limited capacity and only in an up-down direction in the water. Their long-range movements are entirely at the mercy of ocean currents and surface winds and their appearance here every summer of these two species is a perfectly natural occurrence.

Sea2Sky is a free event that does not require tickets or advanced booking. Visit Leisureland and Galway Atlantaquaria anytime from 11am-11pm on Friday, 23 September to take part. For further information visit  http://www.sea2sky.ie/wordpress/

Image © Wiki Commons

One of the more interesting things about exploring marine life is that it often leads to more questions than answers as we constantly encounter elements of the marine world which we will never fully understand. Last week, a phonecall about a stranding of a whale and its calf on a beach just south of here prompted an investigation and sure enough, unearthed a question or two.

The animal in question, now residing most inelegantly between two rocks in the corner of a lonely beach, clearly having given birth to a newborn calf which was some 50 metres away, was similar in size to a dolphin, but its unusually shaped head, lacking a nose or ‘beak’ meant my marine mammal identification skills were put to the test. The blunt square forehead helped me to narrow it down to either a Risso’s dolphin or a pilot whale (which is actually a species of dolphin). Pilot whales very often strand, often in great numbers, however the pilot whale’s fin is far more curved than this animal’s was. The presence of a great number of scratches and scrape marks along the upper part of the body confirmed this to be a Risso’s. This was mystery one solved.

Risso’s dolphins obtain these marks from the teeth of other Risso’s and from bites from squid, one of their main prey items. Why exactly Risso’s are biting each other is, unsurprisingly, not very clear to us yet.
Mystery two arose when we went to record the stranding on the Irish Whale and Dolphin Group’s (IWDG) website. It appeared that the stranding had already been recorded there by a friend, however his recording was two weeks old and only concerned one animal; no calf had been present. Mystery two was thus how the calf managed to end up so close to its mother after two weeks and when exactly did the whale give birth? Closer examination of a photo from that first recording showed the tail of the calf had started to protrude from the mother so indeed she had started to give birth when she stranded.

The last question was what had helped complete the calf’s removal from the mother? Was the calf removed posthumously and by whom? Or what? A beach-going fox was one speculation; the lamb-size calf would be a comfortable carcass for it to work on.

The most fundamental question of course is why do dolphins and whales strand (often alive), on our beaches in the first place? There are various theories, including damage to the animals’ echo-location caused by excessive underwater noise from marine activity, but the only thing we can be certain about is that once again – we’re really not sure.

Image © JP Tiernan

The wind has calmed down for a few days so its a good time to take a look below the surface and see whats happening.

A few weeks ago on a calmish day I did just that and stumbled upon a Spider Crab orgy; so many Spider Crabs, all gathered together, getting pretty social.

Spider crabs (Maja squinado) come into shallow water at this time of the year and gather in large numbers. Here’s one of the tamer photos from this session.

I didn’t get too close as a pinch from one of them hurts like hell and no-one can hear you scream down there…

Image © J Tiernan 2011

Two months of too much wind means that snorkelling season was put back this year. Non-stop blustery winds from the Atlantic meant that, visibility-wise, the water took on the consistency of pea-soup, which isn’t very good for seeing things, whilst the below-average temperatures conspired to further strengthen one’s resolve to not get in the water.
Our inability to snorkel has focused our attention on intertidal rockpools, those condensed microcosms of marine life which occur fleetingly for a few hours each day, ceasing to exist as the tide fills back in around them, robbing them of their independence as they become simply ‘the sea’ again.
Such microcosms of life are perfect in fact, if you wish to introduce the marine world to young seashore enthusiasts, which is what we have been doing for the past month as our duties turn to education at this point in the year. In the last few weeks of term before primary schools break up for the summer, curiosity turns to the outdoors and more and more schools decided this June that a wildlife expedition to the shore, (followed by a surf and a BBQ), is quite preferable to a trip inland to a castle or museum.
There is no match for tiny hands when it comes to finding sea-creatures in and around rockpools; in fact, I’m constantly amazed by the variety of life that a group of primary-school students can unearth. Shore crabs, pipefish and even a large live starfish have been eagerly presented to me on recent shore visits. However, the highlight of this year’s season was an animal not instantly recognisable to most, and as ugly as it is intriguing.
The sea hare (Aplysia punctata), named for its gangling tentacles which resemble a hare’s  ears, is a relative of the periwinkle, its shell strangely contained inside its fleshy exterior. Surprisingly common, but rarely seen, it lives in rockpools amongst the seaweed, reportedly taking on the colour of whatever seaweed it happens to be eating. Juveniles, which mainly eat red seaweed, and adults who eat browns and greens are thus coloured accordingly.
As I dipped my waterproof camera gear, intended for the exotic depths only attainable on snorkel missions, into the shallow rockpool to grab a shot of Aplysia punctata healthily munching on some red algae, I thought this was the underwater photographer’s equivalent of shooting fish in a barrel. But as the primary school students found out this June, sometimes you don’t have to go so far to find some real local treasure.

Image via The Mayo News

Two weeks ago, we mentioned how Féile Bia na Mara, which takes place in Achill this July, is a festival which celebrates the remarkable food that the seas around Mayo produce. One food certainly worthy of celebration in Mayo is the oyster, which fittingly enough, is the showpiece of the opening night of the festival around the island.

Bringing seafood from its wild origins in the undomesticated depths of the ocean to a level of ordered cultivation, which must be both profitable to its investors and clean in the waters around it, is quite a difficult thing to achieve. One such enterprise which appear to have got it right so far, and will be supplying Féile Bia na Mara with oysters is ‘Croagh Patrick Seafoods’ operating out of Roslaher, Kilmeena who harvest oysters daily, year-round in Clew Bay. They farm the tried and tested Pacific oyster (Crassostrea gigas) which has a long shell with a rough deeply ridged exterior and can be harvested year round. They also farm the native oyster (Ostrea edulis), which has a flatter, rounder shell and is only harvested in months with an ‘r’ in them.

As they live off the naturally occurring phytoplankton in the water, not requiring food additives or disease-control, oyster farming is intrinsically clean with the primary concern for the farmer being the control of stocking densities to ensure maximum size and quality of the animal, besides making sure nobody else pollutes the water which is certified ‘Grade A’ by the Department of the Marine who regularly test it.

Croagh Patrick Seafoods also produce mussels and and difficult-to-cultivate clams for their successful ‘shore-to-door’ business. However as owner Padraig Gannon explained to me, 80% of their market is still overseas. Despite being widely acclaimed as nutritional ‘super-foods’, Irish people still haven’t warmed to the health benefits of oysters and other shellfish quite like their peers in Europe, something which festivals such as Féile Bia na Mara would presumably like to change.

Those who love watching marine animals as much as eating them, especially the bigger ones, will have an opportunity to do just that during Féile Bia na Mara. The two groups who represent our marine mammals in Ireland (Irish Whale and Dolphin Group and Irish Seal Sanctuary) will be in Achill during the festival to lead a ‘whale and basking shark watch’ as well as hosting talks and activities all about the biology, ecology and conservation of seals.

See feilebianamara.ie for more info.

This article appeared in The Mayo News edition 28/6/11