red tide

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red tide

natural (and common) phenomenon causing massive extermination of fish and other marine life; caused by algae Karenis brevis or efflorescence of Pfeisteria piscicida.
[in high concentrations of organism, water turns reddish-brown]

red tide

n.
A bloom of plankton, especially dinoflagellates, that causes a usually reddish discoloration of coastal ocean waters. Certain dinoflagellates produce toxins that contaminate shellfish, making them unsafe to eat, and can kill fish.
Environment Harmful algal bloom A body of sea water with high concentrations of dinoflagellates, in which massive algal proliferation imparts a reddish colour to the surface, first described in the Gulf of Maine—US
Management Supportive
Under optimal salinity, temperature and nutrient conditions, marine algae, Gonyaulax catanella and G tamarensis proliferate, producing saxitoxin—a potent neuromuscular toxin that blocks voltage-dependent sodium channels in neurons; not all red tides are toxic and some outbreaks of ‘red tide disease’ occur without the red tide; Gymnodinium breve causes red tide off Florida and in the Gulf of Mexico, but evokes milder neurotoxic reactions—e.g., paraesthesias, abnormal temperature sensation, ataxia, nausea, vomiting and diarrhoea. Saxitoxin concentrates in clams and shellfish—but not in lobster or finned fish; birds, mammals, humans feeding on the shellfish rapidly develop neuromuscular blockade with intense centripetal paresthesias, nausea, vomiting, diarrhea, later vertigo, numbness of face and scalp, sensory loss, dysphagia, dysarthria, intention tremor; if severe, intoxication may cause flaccid quadriplegia or respiratory paralysis and death
Infectious disease A popular phrase from the 1950s that died in the 1960s, for the increased prominence of gram-negative—i.e., ‘red’—bacterial infections, attributed to the indiscriminate use of the first antibiotic, penicillin—which is most effective against gram-positive cocci for most infections—resulting in a relative increase in incidence of gram-negative bacterial infections, causing a ‘red’ shift

red tide

(red tīd)
A natural phenomenon resulting from higher than normal concentrations of the microscopic algae Gymnodinium breve in seawater. When the causative organism is extremely concentrated, seawater can turn a reddish-brown color.

red tide

a bloom of DINOFLAGELLATES which literally turns the sea red. The toxins produced by them, concentrated in shell-fish which may feed upon them, can be fatal to humans.
References in periodicals archive ?
Research on the Prediction Method of Red Tide. Red tide is caused by the comprehensive action of multiple factors, such as the sudden proliferation and accumulation of some plankton [8].
She sprang into action when manatees paralyzed by the red tide started arriving.
A few observations about red tide: First, a pile of thousands of fish corpses is a sobering sight, but the impact on local fish populations is usually not as bad as people think when they see the carcasses.
"The samples collected showed that red tide plankton or organisms, known for its green colour, were significantly detected in the collected samples by up to 92 per cent," the report said."No dead fishes or other marine creatures, however, were seen off the RAK Coasts," the report said.
The ministry is already working on a surveillance programme by satellites to monitor the biological activity on the UAE's west coast so as to react swiftly to tackle the red tide whenever it happens.
In the past, the Florida Department of Health has used reports of dead fish or birds (which eat contaminated fish) as an early warning mechanism for red tide blooms (5).
People with more severe asthma showed greater changes in pre- and post-beach spirometry values during red tide blooms, compared to those with mild/moderate asthma.
At its peak, the 2005 red tide covered more than 67,000 square kilometers of shallow coastal waters--an area larger than the state of West Virginia.
In May 2004, a particularly severe red tide swept 8,000 square km of the East China Sea near Zhejiang Province because of pollution from the nearby Yangtze River.
Algal blooms are called red tides when the cell densities are high enough to change water color, often to red.
Red tides, also known as HABs, or harmful algal blooms, are formed when algae multiply rapidly, reducing oxygen in the water and turning the sea reddish-brown.