Giant African Snail — LANGE 
329 
and the dry season from January to May. The 
mean average temperature at Tanapag during 
1947 varied from 79.7° F. in January to 
82.7° F. in August. This small difference 
would not materially influence activities of 
the snails. The relative humidity is high all 
year around, averaging 82 per cent. Records 
kept at Tanapag during 1947 gave an aver- 
age of 80 per cent relative humidity during 
an 8-month period. 
Rainfall apparently influences activities of 
the snails more than any other single factor. 
The record of the total monthly precipitation 
at Tanapag during 1947 and part of 1948 is 
as follows: 
MONTH RAINFALL 
inches 
1947 
1948 
January .... 
. . . 2.45 
4.47 
February .... 
. . . 1.12 
1.48 
March ..... 
. . . 1.40 
3.68 
April ..... 
. . . 1.26 
4.52 
May ...... 
. . . 1.90 
2.53 
June . 
. . . 1.21 
3.22 
July 
. . . 7.80 
August ..... 
. . . 4.93 
September . . . 
. . . 5.49 
October .... 
. . . 15,20 
November . . . 
. . . 4.00 
December . . . 
. . . 1.42 
From January to June, 1947, there was a 
drought in Saipan, and the rainy season ex- 
tended from July through November. Lim- 
ited observations made on snail activity indi- 
cated that egg-laying periods were definitely 
correlated with periods of extensive rainfall, 
although feeding was possible at any time 
when moisture was present. This was also 
substantiated by an examination of the inter- 
nal genital structures. Specimens collected 
during October and - November had a full 
development of the female organs, whereas 
in specimens collected from February to 
April these structures were atrophied. 
FEEDING HABITS 
On Saipan the snail is omnivorous in its 
feeding habits, but is primarily a scavenger, 
preferring human and animal excreta, gar- 
bage, decaying leaves, rotting fruits, crushed 
snails of its own kind, and soil. At night the 
crackling sound caused by the feeding of 
countless thousands of snails upon decaying 
leaves can be heard for considerable dis- 
tances. In one instance 215 snails were 
counted feeding upon a single decaying 
breadfruit. Plane runways and roads where 
snails were crushed by traffic were favorite 
feeding sites for thousands of snails. 
Of the fruits selected by Achatina , bananas 
(also the leaves and new shoots of banana 
trees), papayas, breadfruit, and ripe passion 
fruits were preferred. The snail caused severe 
damage to certain vegetables such as okra, 
Chinese cabbage, lettuce, melons, and yams. 
It also fed upon beans, carrots, corn, cucum- 
bers, eggplant, pepper, pumpkins, radishes, 
squash, and watermelons. 
An attempt was made to study the feeding 
preferences of the snail in relation to other 
types of vegetation. In general, snails pre- 
ferred weeds and succulent plants to plants 
with thick, leathery leaves. In view of these 
findings the plants listed below will be sep- 
arated into those preferred and readily eaten 
and those not readily eaten. 
The preferred food plants of the snail on 
Saipan, together with the Chamorro name 
(if known) and the family, are listed below: 
CHAMORRO 
FAMILY 
NAME 
NAME 
NAME 
Annona muricata 
Annonaceae 
Amaranth us 
spinosus ' 
kilitis 
Amaranthaceae 
Alhizzia l eh heck 
Leguminosae 
As plenium nidus 
galag 
Polypodiaceae 
Blechum 
pyramidatum 
yerbas babui 
Acanthaceae 
Canavalia . 
gladiata 
gaye 
Leguminosae 
Cassia 
.occidentals 
Leguminosae 
Coluhrina asiatica 
Rhamnaceae 
Grewia 
mariannens 's 
Tiliaceae 
Ipomoea alba 
fofgo 
Convolvulaceae 
Ipomoea 
pes-caprae 
halai hai 
Convolvulaceae 
