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Main => General Discussion => Topic started by: satt-guy on August 22, 2009, 11:17:38 CET



Title: Lights in the sea?
Post by: satt-guy on August 22, 2009, 11:17:38 CET
When i went on a boat in the middle of the night, I saw a lot of small 'lights' like some bioluminescence of some form, in the sea as the boat was moving along in the waters.

can someone please explain what this is?

thanks!


Title: Re: Lights in the sea?
Post by: LapsiBoy on August 22, 2009, 11:20:27 CET
Fosforus.


Title: Re: Lights in the sea?
Post by: Gazzetta on August 22, 2009, 11:21:17 CET
Either there were some longlines and had lights to attract fish to the bait or maybe divers if you were close to land or to a wreck

Chris  8)


Title: Re: Lights in the sea?
Post by: satt-guy on August 22, 2009, 11:22:49 CET
thansk but i cannot find any explanations on the internet on phosphorus and this effect?
no chris they were definitely not longlines/divers!! :)
it was like some material was being churned to the surface from the bottom due to the boat


Title: Re: Lights in the sea?
Post by: Gazzetta on August 22, 2009, 11:25:36 CET
Sometimes when I go for night fishing from cliffs I reel in some sea weed which has some of this "" fosforus "" or what it's called, its really nice to see !!

Chris  8)


Title: Re: Lights in the sea?
Post by: satt-guy on August 22, 2009, 11:31:44 CET
anyone has a "better" explanation?


Title: Re: Lights in the sea?
Post by: Kevin G on August 22, 2009, 11:41:33 CET
sometimes still dark before sunrise, i think they are vopi,  we see like dots of highliter green but loads of it like aliens invading sea :)  don't know what are they, and last friday I saw like a small ray in the dark, its color was white and it was swiming near the surface because I could see the water spreading!! 


Title: Re: Lights in the sea?
Post by: satt-guy on August 22, 2009, 11:42:24 CET
yes exactly kevin g that is it! loads of dots of hilighter green is the exact description!


Title: Re: Lights in the sea?
Post by: baghira on August 22, 2009, 12:06:15 CET
When we go night diving with a torch, we also encounter this fenomena.
Many tiny green spots in the water.


Title: Re: Lights in the sea?
Post by: rammx on August 22, 2009, 12:42:30 CET
i think its a form of plancton  ???...i always see these lights when night fishing


Title: Re: Lights in the sea?
Post by: bigboy on August 22, 2009, 15:14:20 CET
Could it be Jellyfish?? Lastnight the sea was loaded with jellyfish and in the sea they shine a green colour


Title: Re: Lights in the sea?
Post by: fishfinder on August 22, 2009, 17:40:54 CET
in my opinion it's something like fosforus cause even when you anchor the rope will lite green like it was stained with a starlight liquid. ???


Title: Re: Lights in the sea?
Post by: Kevin G on August 22, 2009, 17:53:13 CET
bigboy it can't be jellfish in my case because in the morning it will be clear of jelly fish because you will see us jumping to cool down lool


Title: Re: Lights in the sea?
Post by: MartinB on August 22, 2009, 18:08:09 CET
I see it quite often too,i think it is phosphorus or Bioluminescence i think its called (?) you can see it alot when you fish at night and a boat passes in front of you.Have also seen it like individual lights which move about..maybe krill? All i know is i see this alot in the winter months and when its there there is usually a xabla around :)


Title: Re: Lights in the sea?
Post by: 148148 on August 22, 2009, 19:11:49 CET
During summer reproductive events known as "swarming," females secrete a luminous green mucus-which often draws the attention of human seafarers-before releasing gametes into the water. The bright glow attracts male fireworms, which also release gametes into the bright green cloud. They are microscopic and related to the land glow worms


Title: Re: Lights in the sea?
Post by: EmicMalta on August 22, 2009, 19:36:07 CET
a year ago I was watching a documentary about cattle fish. A technique used by lots of fish to catch their prey is to spread this liquid in the sea. In the video was showing a cattle fish hunting shrimps. She puts this liquid in the hunting area and to feel the movement of a shrimp its really hard, but by these flashes she can "see" it and actually catch it. They where saying that lots of fish that hunt eat at night use this thing. Infact one of the beads with night fishing is exactly the same thing what I said above.


Title: Re: Lights in the sea?
Post by: 148148 on August 22, 2009, 22:37:36 CET
Also if your diving at night with a torch and swoosh your hand around they will glow more as it stirs them up


Title: Re: Lights in the sea?
Post by: Tracina on August 23, 2009, 05:35:15 CET
http://www.youtube.com/watch?v=SWgfSELnzog

Copy and Paste... this link is awsome!! She is the world expert on the topic (at the moment ; )

This is what I study!!!:
The "liquid" you are referring to is kept in the light organs of Cuttle fish and Squid. The luminescence you observe is actually produced by bacteria!!! In fact, the Cuttle fish grows these bacteria within its light organs and "squirts" them around when night-hunting begins. The hunting technique is pretty much the one described by EmicMalta. Two main species of marine luminescent bacteria are called Vibrio fischeri and Vibrio harvey. I study them for my PhD in Ireland as their luminescence-producing mechanism is very interesting. When at low population density, these bacteria are not capable of producing "light", only when these bacteria reach a high population density (high numbers) they communicate with each other using small diffusible molecules and activate fluorescence. The Cuttle fish, some squid, and several other marine creatures have, over the course of milions of years, learned to use this property (a sort of symbiosis). So they grow the bacteria in their light organs and allow them to reach that density necessary for them to become luminescent. Then at night, they release them and use them to attract & detect their prey. So basically it's like having a broth of bacteria in the light organs ready to be used!!! Also, certain squid and small crustaceans use bioluminescent chemical mixtures or bioluminescent bacterial slurries in the same way as many squid use ink. A cloud of luminescence is expelled, confusing or repelling a potential predator while the squid or crustacean escapes to safety.

Hope it was interesting,

Tracina

Interesting links
http://www.youtube.com/watch?v=SWgfSELnzog

http://www.youtube.com/watch?v=SWgfSELnzog


Title: Re: Lights in the sea?
Post by: Tracina on August 23, 2009, 06:18:14 CET
I forgot to say that there are other organisms that light up (for example Dinoflagellates) upon contact (when disturbed). Sometimes you even see them at the keel of the boat as it's going through the water at night. These are not bacteria, but "plankton". Again here is an interesting link:

http://www.lifesci.ucsb.edu/~biolum/answers.html

in particular, read "Why do things light up when disturbed, if this just makes them more vulnerable to attacks?" in the How and Why section... very interesting. As EmicMalta suggested, some predators also take advantage of this phenomenom to identify their prey. Check out these interesting videos for a demonstration!

http://www.youtube.com/watch?v=EN1Yxq8KMsw

http://www.youtube.com/watch?v=4m9MRbG1Nkk

Ciao

Tracina


Title: Re: Lights in the sea?
Post by: fishfinder on August 23, 2009, 08:37:56 CET
Really interesting. Thanks Tracina ;)


Title: Re: Lights in the sea?
Post by: rammx on August 23, 2009, 09:11:48 CET
yes tx alot Tracina,,,you answered a very frequently asked question


Title: Re: Lights in the sea?
Post by: MartinB on August 24, 2009, 01:58:13 CET
Nice one tracina very informative & it explained alot! So the cuttle fish makes that glow..no wonder there is always a scabbard fish around whenever i see it in the winter months  ::) ;D


Title: Re: Lights in the sea?
Post by: Yanyano on September 10, 2009, 15:31:19 CET
Phosforus is usualy found where there is a stable drainage outlet, it reacts due to compounds and gases which are in the dainage.


Title: Re: Lights in the sea?
Post by: Kevin G on September 10, 2009, 17:47:31 CET
mela mhuwiex phosforus li jider jixghel fejn imoru ghal hut ahna ax qas bozz tal-gvern ma tezisti lol


Title: Re: Lights in the sea?
Post by: name on September 10, 2009, 19:39:26 CET
I think you are refering to something like this below..... ;)

What makes a Biobay?

Columbia Encyclopedia: Bioluminescence is production of light by living organisms. Organisms that are bioluminescent include certain fungi and bacteria that emit light continuously. The dinoflagellates, a group of marine algae, produce light only when disturbed.


http://elyunque.com/biobay.html


Title: Re: Lights in the sea?
Post by: caldaland on September 11, 2009, 09:46:44 CET
very interesting indeed name! thank you.