|
The Rio San Lorenzo is situated between the Rio Culiacan to the north, and the
Rio Piaxtla to the south. Most of the headwaters of the San Lorenzo are in
the low mountains of western Durango. Two principal tributaries form the
mainstem of the Rio San Lorenzo: the San Gregorio and the Los Remedios.
The few museum specimens of trout from the San Lorenzo watershed are all from
southern tributaries of the Los Remedios. The San Gregorio tributaries and
the northern tributaries of the Los Remedios are thought to have trout, but are
very difficult to access.

References to "truchas" in the San Lorenzo watershed go all
the way back to the late 16th century to a "carta anua" from
the Jesuit Missionary Hernando de Santaren. Santaren
worked among the Acaxee Indians who had fled to the
mountains to avoid Spanish soldiers.
The trout of the Rio San Lorenzo watershed are similar to
the trout of the Rio Piaxtla. Both are remarkable for
their profusion of parr marks (typically averaging 13 or 14)
and for the abundance of auxiliary parr marks on the lower
sides. The colors of the San Lorenzo trout tend to be
more muted; but the back and upper sides are infused with
purples in the spring.
In the 1950's, the New Mexico Dept. of Game and Fish and the
U.S. Fish and Wildlife Service collected trout from the Rio
Truchas in the San Lorenzo in an attempt to culture them,
and reported them in literature as Mexican Golden Trout.
Attempts to propagate the trout at the National Fish
Hatchery in New Mexico were a failure. |