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Observations on limnological conditions associated with a fish kill of Oreochromis niloticus in Lake Chivero following collapse of an algal bloom

Mhlanga, L; Day, J; Chimbari, M; Siziba, N and Cronberg, Gertrud LU (2006) In African Journal of Ecology 44(2). p.199-208
Abstract
Possible causes of deaths of Oreochromis niloticus in Lake Chivero were examined in relation to changes in limnological conditions monitored over a 25-month period. The fish deaths coincided with the collapse of an algal bloom that had developed and builtup in the lake for 8 months. Chlorophyll a and dissolved oxygen increased to average concentrations of 42.4 mu g l(-1) and 10.9 mg l(-1) respectively prior to the collapse of the bloom. Dissolved oxygen decreased when the bloom started to die off and coincided with the fish deaths when the average surface dissolved oxygen concentration in the lake was 3.9 mg l(-1) and was at a depth of 5 m < 2 mg l(-1). Mortality probably resulted from depressed oxygen levels caused by the high oxygen... (More)
Possible causes of deaths of Oreochromis niloticus in Lake Chivero were examined in relation to changes in limnological conditions monitored over a 25-month period. The fish deaths coincided with the collapse of an algal bloom that had developed and builtup in the lake for 8 months. Chlorophyll a and dissolved oxygen increased to average concentrations of 42.4 mu g l(-1) and 10.9 mg l(-1) respectively prior to the collapse of the bloom. Dissolved oxygen decreased when the bloom started to die off and coincided with the fish deaths when the average surface dissolved oxygen concentration in the lake was 3.9 mg l(-1) and was at a depth of 5 m < 2 mg l(-1). Mortality probably resulted from depressed oxygen levels caused by the high oxygen demand from the massive algal die-off and released algal toxins. This is the first time that die-off of algae has been linked to fish-kills in Lake Chivero as occurs in other hypereutrophic systems. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
African Journal of Ecology
volume
44
issue
2
pages
199 - 208
publisher
Wiley-Blackwell
external identifiers
  • wos:000237691500010
  • scopus:33744479987
ISSN
1365-2028
DOI
10.1111/j.1365-2028.2006.00625.x
language
English
LU publication?
yes
id
d6c7a429-76db-49c4-80d0-62fb26706cdb (old id 159605)
date added to LUP
2007-06-28 14:37:34
date last changed
2019-04-23 02:03:38
@article{d6c7a429-76db-49c4-80d0-62fb26706cdb,
  abstract     = {Possible causes of deaths of Oreochromis niloticus in Lake Chivero were examined in relation to changes in limnological conditions monitored over a 25-month period. The fish deaths coincided with the collapse of an algal bloom that had developed and builtup in the lake for 8 months. Chlorophyll a and dissolved oxygen increased to average concentrations of 42.4 mu g l(-1) and 10.9 mg l(-1) respectively prior to the collapse of the bloom. Dissolved oxygen decreased when the bloom started to die off and coincided with the fish deaths when the average surface dissolved oxygen concentration in the lake was 3.9 mg l(-1) and was at a depth of 5 m &lt; 2 mg l(-1). Mortality probably resulted from depressed oxygen levels caused by the high oxygen demand from the massive algal die-off and released algal toxins. This is the first time that die-off of algae has been linked to fish-kills in Lake Chivero as occurs in other hypereutrophic systems.},
  author       = {Mhlanga, L and Day, J and Chimbari, M and Siziba, N and Cronberg, Gertrud},
  issn         = {1365-2028},
  language     = {eng},
  number       = {2},
  pages        = {199--208},
  publisher    = {Wiley-Blackwell},
  series       = {African Journal of Ecology},
  title        = {Observations on limnological conditions associated with a fish kill of Oreochromis niloticus in Lake Chivero following collapse of an algal bloom},
  url          = {http://dx.doi.org/10.1111/j.1365-2028.2006.00625.x},
  volume       = {44},
  year         = {2006},
}