July, 1999 
SCAMIT Newsletter 
Vol. 18, No.3 
In addition to the numerous new species 
encountered, and the large number of range 
extensions, ecological information on the trawl 
caught animals was also provided. CTD casts 
in association with most of the trawls have 
yielded bottom temp., bottom DO levels, and 
sediment type information for the first time for 
most areas. These have been reported, where 
available, in the published papers. Synthesis of 
the distributional data has yielded several 
interesting patterns, including one of very low 
oxygen or anoxic conditions at and below 250 
m depths on the upper slope off much of West 
Mexico. Catches in these depths were not very 
diverse, although the animals able to tolerate 
these low-oxygen conditions were often 
relatively abundant. A large gap in reports of 
many soft bottom species occurs off Colima 
and Oaxaca, where rocky bottom is the rule. 
Effort has been low in this area relative to 
others, so there have been few reports of any 
kind. Dr. Hendrickx is confident that ongoing 
field efforts in association with local captains 
and pilots will help locate the more scattered 
soft bottom habitat for sampling. South of this 
rocky intrusion the sandy bottom is again 
encountered, as are much the same suite of 
invertebrates which were seen north of it. 
Another area with fewer species taken than 
expected is the Gulf of Tehuantepec. In 
investigation after investigation fewer taxa are 
taken there than expected. Ranges of numerous 
species extend through the area, but diversity 
in any sample is always higher either north or 
south of the Gulf. No explanation is yet 
forthcoming. 
Current and future projects involve a 
broadening of his focus to accommodate the 
needs of his students. He is currently 
undertaking a complete inventory of the 
isopods of the western coast of Mexico. He and 
a student have already published the first 
papers on the group (Hendrickx & Espinosa- 
Perez 1998a,b), although the specimens on 
which the first of these papers is based have 
been siting on his desk since the 70’s: just too 
much to do. Fortunately in the next year or so 
his stint as director [along with all the 
associated administrative duties] will come to 
an end, and he will have a bit more time for 
research. The station is also deeply involved in 
increasing the computer-based accessibility of 
their collection data. Dr. Hendrickx indicated 
his hope that shortly their database will be fully 
accessible over the internet. Published lists of 
the holdings of the station museum have also 
been prepared and are available. Specimen 
resources so detailed become easily available 
to distant workers, at least in theory. 
Movement of specimens across international 
borders from Mexico to the U.S. and/or from 
the U.S. to Mexico remains difficult and 
involved. 
Most of the effort over the years has been 
expended on the decapods, and secondarily on 
the stomatopods (Dr. Hendrickx’ main interest 
when he first arrived in the late 1970’s). He 
showed us a table on the known biota of the 
Gulf of California, evaluation of which is an 
ongoing effort. Effort will gradually shift to fill 
in some of the “blanks”, the areas where little 
or nothing is known. The majority of the 
reported amphipods, for instance, were 
hyperiids (due to the efforts of a graduate 
student and a thesis project), plus those listed 
by Jerry Bernard in his Gulf paper. This list of 
gammarids is undoubtedly very incomplete, 
but no other information on the amphipod 
fauna of the Gulf is available. Leptostracans 
are even more poorly known; there are no 
species recorded from the Gulf. Small 
peracarid groups such as the cumaceans, 
tanaids, etc. are virtually unknown from the 
Gulf. Non-arthropods are poorly known, the 
exception being the mollusks, and to some 
extent the polychaetes. Larger cnidarians and 
echinoderms are relatively well known, but the 
small species in these phyla are largely 
unknown. Efforts will continue towards 
documenting the biota of this body of water in 
future. 
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