Notes on the Mosquitoes of Nissan Island, Territory of New Guinea^ 
Marshall Laird^ 
Nissan Island, also known as Green Island, 
Sir Charles Hardy Island, or Los Caimanes, 
lies approximately halfway between the 
Solomon Islands and the Bismarck Archi- 
pelago. Some 50 miles east of southern New 
Ireland (Bismarck Archipelago) and 40 miles 
northwest of Buka (northern Solomons) , it is 
in line with the main chain of the Solomons. 
The island is an elevated atoll, the seaward 
cliffs of the eastern side, in places upwards of 
100 feet in height, owing their formation to 
gentle tilting associated with the elevation 
(Davis, 1928). An area of about 7 miles by 
4 miles is enclosed by the atoll rim, which is 
never more than a mile, and often only a few 
hundred yards, in width. Before its military 
occupation Nissan was densely bushed, with 
the exception of two coconut plantations and 
a few native clearings. Some earlier accounts 
have overestimated the size of the island. 
Thus Schmiele (1891) speaks of it as being 
15 miles in diameter with a rim 2 or 3 miles 
wide, and Hartert (1926) gives its dimensions 
as '’about 27 km. long and 21 wide.” 
Nissan was held by the Japanese from 1942 
to February, 1944, when an Allied force 
which included the Third New Zealand 
Division recaptured it. Two airstrips were laid 
down, and the island was used as an Allied 
air base until the middle of 1945. The local 
incidence of Anopheles and malaria being high, 
strict mosquito control was maintained 
throughout the military area during this 
period. Thus the initial malaria rate was low, 
only 46 cases being recorded among 6,922 
^Royal New Zealand Air Force Entomological 
Bulletin No. 8. Authorized by Chief of Air Staff. 
Manuscript received September 4, 1951. 
^Entomologist, Medical Branch, Royal New Zealand 
Air Force. 
New Zealand troops during the 3-month 
period from the landing until the departure 
of the Division in May, 1944. During the re- 
mainder of the Allied occupation, cases of 
primary malaria were infrequent and were 
usually traceable to infection outside the 
controlled area. 
When Nissan was abandoned as an opera- 
tional base, malaria control had been in force 
for almost a year and a half. The material 
discussed below was collected during a 10- 
day visit to the island in September, 1945. It 
was of particular interest to note how rapidly 
and completely Anopheles had reoccupied the 
abandoned base in the 2 months which had 
elapsed since the cessation of mosquito con- 
trol activities. 
Three species of mosquitoes have previous- 
ly been recorded from Nissan: Anopheles 
{Myzomyia) farauti Laveran, recorded by 
Perry (1945); Tripteroides {Tripteroides) nis- 
sanensis Lee, described from material collected 
by L. J. Dumbleton; and Aedes {Finlay a) 
kochi (Donitz), recorded by Marks (1947) 
from material collected by L. J. Dumbleton. 
T. nlssanensls was not recorded in the present 
survey. The other two species and the follow- 
ing four additional ones were collected: 
Aedes (Stegomyla) quasiscutellaris Farner and 
Bohart, Aedes (Aedes) earmend Edwa.rds, Armi- 
geres hreinli (Taylor), and Culex (Culex) an- 
nulirostris Skuse. 
THE BIOLOGY OF MOSQUITO LARVAL HABITATS 
The vegetation of ground pools on the 
overgrown Tangalan plantation closely re- 
sembled that of similar pools in New Britain 
(Laird, 1947) and the Solomons. Paspalum 
conjugatum Berg., Echinochloa colona O. 
Kuntze, and Eleusine indica Gaerter were the 
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