The Arrival of Aedes ( Ochlerotatus ) vigilax (Skuse) in Fiji 
G. F. Burnett 1 
The saltmarsh-breeding mosquito, Aedes 
( Ochlerotatus ) vigilax (Skuse), is a serious pest 
in parts of Australia, New Guinea, and New 
Caledonia and is a proved vector of the New 
Caledonian strain of nonperiodic bancroftial 
filariasis (Iyengar and Menon, 1956; Iyengar, 
1954; Backhouse and Woodhill, 1956). It was 
reported from Fiji by Lever (1940), but he 
subsequently decided that this was an error 
(Lever, 1945). In November, 1957, A. vigilax 
was discovered near Suva and identified with 
certainty. Some work has been done on this 
species since its discovery to determine its status 
as a potential vector of Fijian filariasis and also 
to find out how it entered the colony. In com- 
mon with most Pacific territories, Fiji enforces 
measures designed to limit the importation of 
pests (especially anopheline mosquitos, which 
are absent from the group), but A. vigilax had 
obviously evaded these measures. 
Acknowledgments: I wish to thank Mr. D. J. 
Lee, of the University of Sydney, and Mr. P. F. 
Mattingley, of the British Museum (Natural 
History), for their very prompt identification 
of the specimens I sent them. Mr. Lee also sup- 
plied most of my information on this mosquito 
in its natural haunts. I am indebted to Messrs. S. 
Nelson, G. Martin, J. Buckingham, and M. Na- 
tuna, all of the Medical Department, Fiji, for 
much information. The dissections were largely 
carried out by Isimeli M. Rakai. My thanks are 
due the Director of Medical Services, Fiji, for 
permission to publish this note. 
ARRIVAL OF A. vigilax 
The Fiji group consists of two large islands 
and numerous smaller ones. The southeast as- 
1 Formerly of Filariasis Research Unit, Fiji. Present 
address: Colonial Pesticides Research Unit, P. O. Box 
3024, Arusha, Tanganyika, East Africa. Manuscript 
received April 8, 1959- 
pects of all the higher islands, including the 
two large ones, are wet, receiving 100-300 in. 
of rain per year, and in normal years are not 
without rain for more than a week or two at a 
time. The northwest sides of these islands have 
a distinct rainy season from December to May, 
the rest of the year being dry. Ports of entry 
from overseas are virtually confined to the largest 
island of Viti Levu (see Fig. 1). There are two 
seaports concerned, the capital, Suva, in the 
southwest, and Lautoka in the northwest. On 
the east side of the Suva peninsula is the mil- 
itary and civil flying-boat base of Lauthala Bay. 
The international airport of Nandi is not far 
from Lautoka. 
On December 20, 1957, mosquito larvae sub- 
sequently identified as A. vigilax were dis- 
covered by the local mosquito control organiza- 
tion in brackish pools at the mouth of a creek 
within a mile of the flying-boat base at Lau- 
thala Bay. These pools were oiled as soon as the 
larvae were found, but on January 13, 1958, 
both adults and larvae were discovered in and 
near brackish pools about 100 yd. from shore 
some 1,000 yd. northeast of the original dis- 
covery. On succeeding days the infestation was 
traced, principally as sparse adults, as far as the 
extensive delta of the Rewa River. During Janu- 
ary and February specimens were found at Koro- 
tongo, 60 mi. west of Suva, and at Mau, Wai- 
niambia, and Nukui (Fig. 1 ) . At all these places 
we had made regular surveys at intervals dur- 
ing the previous 9 months and it is most un- 
likely that A. vigilax would have been over- 
looked unless it was present in very small num- 
bers indeed. At the end of January and begin- 
ning of February unusually high tides, backed 
by strong winds, produced many brackish pools 
suitable for breeding, and many places in south 
and east Viti Levu complained of being attacked 
by swarms of the new mosquito, which was 
sufficiently distinctive to attract lay comment as 
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