29
August 2002
Marine biology: Fish meal
The protozoan Pfiesteria piscicida has been blamed for killing millions of mid-Atlantic menhaden fish along America's East Coast, but no toxins have been identified that would explain the phenomenon, leading to suggestions that another pathogen might be involved. New lab experiments may now have solved part of the mystery. Sheepshead minnow larvae died only when in direct physical contact with P. piscicida and P. shumwayae dinospores, suggesting that secreted toxins are not to blame. The fish are not being poisoned but eaten — tissue damage then weakening their defences against fungal or bacterial attack.
Pfiesteria shumwayae kills fish by micropredation
not exotoxin secretion
WOLFGANG K. VOGELBEIN, VINCENT
J. LOVKO, JEFFREY D. SHIELDS, KIMBERLY S. REECE, PATRICE L. MASON, LEONARD W.
HAAS & CALVIN C. WALKER
Nature 418, 967–970 (2002);
doi:10.1038/nature01008
| First
Paragraph | Full
Text (HTML / PDF) |
Marine biology: Unveiling an ocean phantom
VERA L. TRAINER
Certain episodes of mass fish mortality
in coastal waters off the eastern United States have been ascribed to a planktonic
organism called Pfiesteria. There are now fresh clues to how these fish
are killed.
Nature 418, 925–926 (2002); doi:10.1038/418925a
| Full Text (HTML /
PDF) |
