In laboratory bioassays we tested the predatory capacity
of the copepod
Mesocyclops annulatus
on
Aedes aegypti
and
Culex pipiens
larvae. A single adult female of
M. annulatus
caused 51.6% and 52.3% mortality of 50 first instar larvae of
Ae. aegypti
and
Cx. pipiens
respectively, in a 72 h test period. When alternative food was added to
the containers, mortality rates declined to 16% and 10.3% for
Ae. aegypti
and
Cx. pipiens
respectively. When 50 first instar larvae of each of the two mosquito species
tested were placed together with a single adult female of
M. annulatus
, mortality rates were 75.5% for
Ae. aegypti
larvae and 23.5% for
Cx. pipiens
larvae in a three day test period. Different density of adult females of
M. annulatus
ranged from 5 to 25 females produced mortality rates of
Ae. aegypti
first instar larvae from 50% to 100% respectively. When a single adult female
of
M. annulatus
was exposed to an increasing number of first-instar
Ae. aegypti
larvae ranging from 10 to 100, 100% mortality was recorded from 1 to 25
larvae, then mortality declined to 30% with 100 larvae. The average larvae
killed per 24 h period by a single copepod were 29.
