The ABCDEF of jellyfish sightings
If you see a jellyfish when diving… Dr. Tom Doyle is interested! Simple observations such as the location and depth can be very informative. To make reporting such observations easier Tom has developed the ABCDE of jellyfish sightings. Then simply report on www.jellyfish.ie
A) Aggregations of jellyfish? Have you seen an aggregation
(bloom/swarm) of jellyfish? If so, what was the jellyfish species,
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?
E) Eaten alive? 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 Britain’ with Irish Ferries.
So be a jellyfish nerd and test your dive buddies – do you know
the Jellyfish Code (ABC..)!
Images from top down: Michelle Cronin, Tom Doyle, Patricia
Byrne, Oliver Buckley, Amy Dale and Oliver Buckley
