FISHES OF EL SALVADOE 
239 
offshore varied from 4.5 to 16 meters. Lake Ilopango, with an area of 70 square 
kilometers, and Lake Coatepeque, with an area of 30 square kilometers, are beau- 
tiful, deep, clear bodies of water having considerable vegetation along the shores, 
some of the plants growing at a depth of 7 meters or more. The plants consist 
largely of Chara, Ceratophyllum, and Naias, the plant growing at the greatest 
depth being Naias marina. Lake Ilopango has an outlet, but Lake Coatepeque 
has none, and the water in the latter has a slightly salty taste, the sodium chloride 
content, according to an analysis posted in a local hotel, being 0.4465 grams per 
liter. The maximum depth of Lake Ilopango was not obtained, as the lake was too 
rough at the time of our visit to make vertical soundings with the apparatus at hand. 
The greatest depth found in Lake Coatepeque was 83 meters. Hook and line 
fishing from the native raft, the "balza," is carried on in this lake to a depth as 
great as 30 meters, and the species taken at the greatest depth is CicMasoma mota- 
guense. In Lake Ilopango food fishes are scarcer than in any other lake visited. 
This may be due to overfishing stimulated by its proximity to San Salvador, where 
fishes command a fancy price. 
Lake Olomega is another lake of considerable size, having an area of 20 square 
kilometers. This lake is shallow, having an average depth of scarcely 2 meters, 
and the water is turbid. Vegetation is abundant along the shores where they are 
not too rocky. The country also has quite a number of smaller lakes, among which 
Metapan,! Ahuachapan. Chalchuapa, Zapotitan, and Chanmico were visited. 
Among these lakes Metapan and Ahuachapan are shallow and afford some of the 
best fishing found in El Salvador. Chalchuapa and Chanmico are quite deep and 
food fishes are scarce, while top minnows are very abundant. Lake Zapotitan 
covers considerable territory, but it can scarcely be considered more than a swamp 
that is so densely overgrown with vegetation that a boat can not be used. 
The Rio Lempa, the largest river in El Salvador, was visited at Suchitoto and 
San Marcos, and collections were made at each place. Collections were made in two 
of its tributaries also, namely, in the Rio del Desague near Lake Guija, of which it 
forms the outlet, and in the Rio Sucio at Sitio del Nino. In the Rio San Miguel, a 
much smaller stream than the Lempa, a collection was made at San Miguel. In 
the Rio de Paz basin collections were made in the Rio Molino near Ahuachapan 
and in the Rio Pampe near Chalchuapa. One day was devoted to collecting in the 
small mountain streams near San Salvador, some of which empty into Lake 
Ilopango and some into the Rio Lempa. 
All the streams of El Salvador that were seen are rocky, having rapids and 
comparatively large, deep stretches between the rapids. Sand and gravel are found 
only occasionally, and collecting with drag nets is difficult. The natives use cast 
nets both in the streams and in the lakes. Hook and line fishing also is engaged in 
in some localities. 
The temperature of the water at the surface in the different lakes and streams 
ranges from about 74 to 83° F., the average being close to 78°. The difference 
between the bottom and the surface temperatures in the lakes is small. In Lake 
I In the vicinity of the city of Metapan is located a group of lakes known as "Laguna de Metapan," which are all connected 
during the rainy season but which become separated during dry weather. The collections reported in this paper were made in 
the small division of the Laguna de Metapan located nearest the city of Metapan, 
