The Big Jellyfish Hunt

The Big Jellyfish Hunt If you see a jellyfish we are interested! And your photos are worth their weight in gold! Have you seen an aggregation (bloom/swarm) of jellyfish? E) Eaten alive?

The ABCDEF of jellyfish sightings

If you see a jellyfish when diving… we are interested! Simple observations such as the location and depth can be very informative. To make reporting such observations easier we have developed the ABCDE of jellyfish sightings. Then simply report on the wall of this page or go to www.jellyfish.ie


A) Aggregations of jellyfish? If so, what was the jellyfish specie

s, how many jellyfish were in the swarm (10s, 100s, 1000s, or greater), did the aggregation form a discrete layer at certain depth or was it throughout the water column)? B) Barrel jellyfish? Have your seen a barrel jellyfish? If so, where did you see it and what size was it (saucer, dinner plate, dustbin lid size)? C) Cyanea jellyfish? Have you seen the Lion’s Mane Jellyfish (Latin name is Cyanea capillata)? If so, where did you see it and what depth did you see it at? D) Dead jellyfish? Have you seen dead (or alive) jellyfish on the seabed? If so, what species was it and was there more than one jellyfish? Have you seen any animal eating a
jellyfish? For example, have you ever seen a sea anemone or a crab eating a jellyfish? F) Fish and jellyfish? Have you seen fish swimming with jellyfish? If yes, how many fish were with the jellyfish (0, 1, 2, 3-5, 6-10, 11-15, 15-20, 20-30, 30+), where did you make this observation and time of day/night? For all jellyfish sightings important things to report include: the species of jellyfish, the size of the jellyfish (saucer, dinner plate, dustbin lid size), the water depth of observation, the water temperature, the location of sighting (500m east of Dalkey Island), the date and time of sighting. And remember that photographs are worth their weight in gold! Indeed, the best jellyfish photo of the year will win a Voucher for ‘Free trip for a car and 2 persons to Ireland’ with Irish Ferries. So be a jellyfish nerd and test your dive buddies – do you know the Jellyfish Code (ABC..)!

Abstract submission for JBS8 extended to 6th Feb (next Friday).
30/01/2026

Abstract submission for JBS8 extended to 6th Feb (next Friday).

Abstract submission extended to February 6th. Looking forward to get more interesting contributions

For all jellyfish researchers and enthusiasts, please note that the Deadline for abstract submission is approaching.
21/01/2026

For all jellyfish researchers and enthusiasts, please note that the Deadline for abstract submission is approaching.

REMINDER - Deadline for abstract submission

Just a friendly reminder that the deadline for the submission of abstract is coming up soon 31st of January

Delighted to announce that the 8th world Jellyfish Blooms Symposium (JBS8) has just launched its webpage. The Jellyfish ...
11/12/2025

Delighted to announce that the 8th world Jellyfish Blooms Symposium (JBS8) has just launched its webpage. The Jellyfish Blooms Symposium (JBS) is the recurrent gathering of the global jellyfish research community. JBS aims to bring together researchers from all over the world to meet, share up-to-date research on the topic, inspire researchers, and develop to collaborations. Over the past few decades, scientific interest in jellyfish (gelatinous zooplankton) has grown remarkably. Click on the link to learn more about it.

International Jellyfish Blooms Symposium (JBS) is the recurrent gathering of the global jellyfish research community.

23/11/2025

Excited to say the 8th World Jellyfish Blooms Symposium has a page which will post announcements and information about JBS8. https://www.facebook.com/share/14NqB8W3N3F/

We are delighted to say that the Jellyfish Blooms Symposium 8 (JBS8) will be held in Cork, Ireland from Monday 29th June (opening plenary and reception) until Friday 3rd July 2026.

17/09/2025
19/08/2025

Hi folks, we just had a report of a likely bloom of mauve stingers (Pelagia noctiluca) on the west coast, near Aughris, Connemara (Galway). The swimmer was stung and described “a soup of tiny brownish jellies with many purple jellyfish”. Most probably this is a bloom of mauve stingers. Mauve stingers are beautiful and fascinating jellyfish, but they can give a bad sting so keep an eye out for them. See below video of mauve stingers captured by Prof. James Bell in Lough Hyne last year. Please let us know if you see any jellyfish and post your images here.

To all jellyfish researchers, we very much look forward to seeing you in Cork, Ireland, for the 8th International Jellyf...
01/08/2025

To all jellyfish researchers, we very much look forward to seeing you in Cork, Ireland, for the 8th International Jellyfish Blooms Symposium ( ). For more information go to this placeholder webpage: https://www.ucc.ie/en/bees/research/jellyfish26/

Hi folks, we have just received reports that a Portuguese man-o’-war has washed up in Inner Galway Bay (near Clarinbridg...
31/07/2025

Hi folks, we have just received reports that a Portuguese man-o’-war has washed up in Inner Galway Bay (near Clarinbridge!). If you see one please let us know by posting here but it would be great also if you could log your observation on the National Biodiversity Data Centre too. Many thanks to Colin for the observation in Galway. (Photo below is not of the actual Portuguese man-o’-war that was reported but of similar size).

Hi folks, a global study on the genetics of the Portuguese man-o’-war (or Physalia spp.) has revealed that there are fou...
20/06/2025

Hi folks, a global study on the genetics of the Portuguese man-o’-war (or Physalia spp.) has revealed that there are four species found across our oceans, and not just the one! For decades we believed that the blue bottle in Australia and the Portuguese man-o’-war that washed up in South Africa, Hawaii or Ireland were all the same species. However, new research which used next generation sequencing to analyse 151 specimens from around the world clearly shows that there are four different species of Portuguese man-o’-war. Those that wash up in Ireland are closely associated with those on the east coast of America, Portugal and the Azores, and represents a distinct species just found in the Atlantic. The other three species have distinct but overlapping ranges with one species just found in the Tasman Sea area. The research was led by scientists from Yale University, but scientists from over the world contributed, including University College Cork. A huge shout out to our wonderful jellyfish recorder Rosemary Hill who found two Portuguese man-o’-war on a beach in Kerry that were used in this study. You can read the research here. https://authors.elsevier.com/c/1lIAf3QW8SA33h

Hi folks, two sea turtles have washed up in the last few days so please keep a look out for them when out walking your l...
24/12/2024

Hi folks, two sea turtles have washed up in the last few days so please keep a look out for them when out walking your local beach.

Hi folks, there has been a lot of interest in mauve stingers (Pelagia noctiluca) in the past few days because of what ha...
09/11/2024

Hi folks, there has been a lot of interest in mauve stingers (Pelagia noctiluca) in the past few days because of what has happened in Lough Hyne and the south coast. However, it is important to note that mauve stingers are not new to Ireland. The pioneer Maud Delap described “immense shoals” of them in Valentia harbour over a hundred years ago, and others have recorded them in the 30s, 50s and 80s. More recently, we carried out surveys for mauve stingers from 2008 to 2018 with the Marine Institute. What we found was that they were present in large abundances in 8 out of the 11 years (see image below from our published paper). So, they are not new and clearly are an extremely abundant and important component of our seas. However, it is a first for Lough Hyne and the abundances of large slicks (or shoals) being described along the south coast is noteworthy. I have personally observed such slicks (some many kilometres long), but these observations were 10s or 100s kilometres from land, in oceanic waters. One big question is how such oceanic jellyfish end up inshore!

Hi folks, it appears the mauve stingers are way more widespread on the south coast, than just Cork beaches and Lough Hyn...
09/11/2024

Hi folks, it appears the mauve stingers are way more widespread on the south coast, than just Cork beaches and Lough Hyne. See below Instagram post (many thanks to Franklin for capturing and sharing it) of numerous slicks of mauve stingers off a swimming cove near Tramore, Co Waterford. There must be 100,000s, if not millions of mauve stingers there.

https://www.instagram.com/reel/DCJTeV4NSZv/?igsh=YjR4eXFzam9ueWZl

Address

Doneraile

Website

Alerts

Be the first to know and let us send you an email when The Big Jellyfish Hunt posts news and promotions. Your email address will not be used for any other purpose, and you can unsubscribe at any time.

Contact The School

Send a message to The Big Jellyfish Hunt:

Shortcuts

Share

Category