|
Abstract:
|
The abundance of benthic macroinvertebrates during March-October 1969 in West Bay, Texas, was compared between a natural marsh area, an adjacent marsh area altered by channelization, bulkheading, and filling, and an open bay area. Animals representing four phyla were caught. Abundance indices (areas combined) of the four groups in terms of numbers were 66.4% polychaetes, 29.6% crustaceans, 2.5% pelecypods, and 1.5% nemerteans; volumes were 44.0% polychaetes, 40.8% pelecypods, 10.7% nemerteans, and 4.4% crustaceans. When all organisms were combined, they were slightly more abundant numerically and over twice as abundant volumetrically in the marsh than in the canals and were least abundant in the bay. In general, the seasonal abundance of polychaetes and nemerteans varied little during the study, whereas crustaceans and pelecypods were abundant only during the spring and early summer. |