red tides????

have any of ye ever heard of a red tide. until recently i've never heard of them, but i've been fishing alot in kilkee bay recently which is a very sheltered bay and the beach can get a pretty big build up of sea weed on it after storms. anyway, lately, people(not locals) keep walking up to me and asking me if it's a red tide. i havn't a clue, they were all on about a strong smell of ammonia and it being a bad time to collect shell fish.... personally it sounds like a bit of an old wives tale, the smell just comes from the rotting sea weed, and i don't see any correlation between rotting sea weed and dodgy mussels.....but i was wondering if any of ye had ever heard of it, and in fact there was any truth in it...

RED TIDE:
Not every plant poisoning is caused by a large, terrestrial plant. Several microscopic marine algae are notoriously poisonous to hapless humans who consume them in shellfish.
These Algae are tiny, single-celled plants that, like plants on land, capture and use the sun's energy to grow. The growth of algae is an essential life process, as it is the first step in transferring solar energy into aquatic food webs. The huge variety of marine algae are typically subject to annual cycles of growth & decay. These organisms thrive and multiply principally during the spring and summer, in response to increased light intensity and favourable levels of salinity & nutrients in ocean water. During the growth period, or bloom, each single algae cell may replicate itself one million times in two to three weeks.

During the reproductive riot of the bloom, warm, shallow seawater tends to become discoloured by the sheer concentration of algae seeking the sunlight. This discolouration is a result of the various pigments the plants use to trap sunlight; depending on the species of algae present, the water may reflect pink, violet, orange, yellow, blue, green, brown, or red. Since red is the most common pigment, the phenomenon has come to be called Red Tide.

Most species contributing to algal blooms are harmless, BUT (another big but!) some species are poisonous to animals which feed upon them directly or indirectly. Some of the toxins these species produce are seriously toxic. Often, the algae themselves are unaffected, as are the filter feeders, especially shellfish, for whom micro-algae are the principal diet. However, to carnivores further up the food chain, including humans, these toxins are potentially FATAL.

cheers wes, similar to the blue green algae you get on lakes in the summer, but the red tide has nothing to do with decomposing seaweed, it's caused by the annual increase in light intensity and water temperature.......so i was right to call those tourists a shower of lunatics and tell them piss off and leave me alone ya??......

by the way before i get in trouble i didn't dream of tellin them to piss off! i just told them i never heard of it

Wes,

In fairness to the author you should quote your source.


Ross

Frodo,

Follow this link under Phytoplankton.
There is a reference to Red Tide.

[url]http://homepage.tinet.ie/~sherkinmarine/referenc.htm#Phytoplankton[/url]



Ross

Glad you asked the question Frodo and thanks , Wes , for the comprehensive reply , where-ever it came from !
I occasionally collect shellfish for the table . Have seen the safety warning signs ( as in official signs ) but when I last called the number they give I found that the "updates" were so old as to be meaningless .
Does anyone know of any natural signs , other than unusual colour of water ? ( I guess even that may not be reliable when the current reduces density of algae ) . Don't tell me I'll know when I've been head down in the john for the third day !
Cheers
Blowin

My source is the Canadian Nove Scotia Nature Museum website, Ross.
If you feel the urge to know the name of the author, feel free to look.

http://museum.gov.ns.ca/poison/redtide.htm

In Ireland we have an early warning system for redtides and shellfish safety. Shellfish can be toxic to humans, from naturally occuring microalgae, even without seeing the water discoloured. The shellfish producing areas of the country are monitored on a weekly basis by taking samples of shellfish and by taking water samples. These tests are carried out by the Marine institute and e-mailed, phoned and posted on their web pages. If you go to http://www.marine.ie and click on 'Shellfish safety' under their popular pages you can follow the links to find your areas and monitor harmful algae blooms. Red tides on the scale talked about earlier thankfully do not happen very often but I have to say again they are perfectly natural.

Tight Lines

There are loads of largish mussels in some locations near me, i see them when im digging lug and alway wonder can i just pull a few handfuls from the rock's take them home and cook them up for my supper? What about other pollutants in the water? :?: Are they safe to eat :?: I remember digging for cocles as a kid and eating them with out any appartent ill effects....

Anyone regulary collect there own shell fish? Any tips ?

thanks

I remember digging for cocles as a kid and eating them with out any appartent ill effects....

I remember when I was a kid, drop a sweet, pick it up and bless it, then straight back into the gob :shock:
Maybe becoming older and wiser isnt such a good thing!! :wink:

cool thanks for all the info lads......i had spent a semester last year in college studying water toxicoligy and i had never come across red tides(but everything we did was based on freshwater environments) i suppose if you took eveything you read seriously you'd never eat another fish or go swimming again!

Wes.... I saw some study suggesting kids where more vunerable to infection and even ashmia now a days coz they don't get a "healthly amount" of exposer to germs and bacteria when they are young. Parents over zelous with the cleaning products, bleaching everything and kids not picking up sweets of the floor anymore etc etc..

Don't know if its true but i never clean the house and im never sick.. :lol:

Have you ever night fished and saw the glittering on the water almost like little luminous lights. I assume this is something to do the the red tide also because they say when you see this "soilse dolas" (not sure if I got the lrish spelling right but an old local in Valentia said that was the local name for it) then you should avoid eating the shellfish.

I have certainly seen this on the east and west coasts.

Donal.

the glow in the dark specks are are form of plankton that are bio luminescent. certain marine mammals do it(watch david attenboroughs blue planet with the deep sea jellyfish, absolutely amazing) certain squid do it too. i never heard that these plankton should be avoided, but what i do know, is if you go for a swim in the sea at night time, and there are high concentrations of them in the water, then take a leak, and watch it glow!!!!! i'm serious! it's one of the funniest things i've ever seen!!!!

here's a cool web site on bio luminescence.
http://www.lifesci.ucsb.edu/~biolum/

also watch the movie the hulk(the new one) the hulk supposidely obtained his cool green colour through the use of bio luminescent jellyfish in the experiments carried out to help create a super soldier!
i'll be quiet now.....

Have seen these when swimming at night in thialand before, they look amazing, glow up when you distrub the water or splash about. Didn't realise that they occured n Ireland though...can't see myself swimming at night here though..unless im wrapped in a nice thick wet suit :lol: