Appendix 6.3(3). Data acquisition for fish species 

 of the Chenier Plain. 



Notes on the trophic relations, local distributions, relative abun- 

 dance and economic importance of most fish species known to occur in the 

 Chenier Plain are present in the tabular format for the Nearshore Gulf and 

 Inland Open Water habitats. 



In contrast to certain other groups of organisms, fishes of the Che- 

 nier Plain have received little study. Consequently the information pre- 

 sented here is derived in large part from the literature, with emphasis on 

 that pertaining to fairly well-studied (and ecologically similar) adjacent 

 areas — namely, the Galveston Bay System to the west and the Vermilion- 

 Atchafalaya Bay complex to the east. For many species, information derived 

 from informal unpublished observations were included. 



Information on trophic relations is available for most of the species, 

 either from regional food habit analyses or by inference from observations 

 on the species or close relatives in other areas. Within a given feeding 

 type (e.g. predator, strainer, grazer, etc.), fishes tend to be highly op- 

 portunistic and consume virtually any ingestible materials that are avail- 

 able. Among estuarine species there tends to be considerable overlapping 

 of feeding types, especially when various life-history stages are considered 

 (Darnell, R. M. 1958). 



Habitat relations are summarized under the heading Local Distribution. 

 The position normally occupied by the species in the water column (e.g. 

 demersal, pelagic) was noted. In this context the term "pelagic" was used 

 in reference to fishes typically not associated with the bottom, as opposed 

 to the biogeographic connotation of the word (i.e., open ocean dwelling) 

 which has no relevance here. Horizontal patterns of distribution were also 

 noted, since many species tend to occupy mainly the narrow zone along the 

 beach, deeper areas farther offshore, or places where special substrate 

 conditions obtain (e.g., reefs, wrecks, oil platforms, etc.). Inland Open 

 Water Habitat entries for this category emphasize salinity zones and major 

 types of water bodies such as river channels, marsh bayous and lakes, swamps, 

 and so forth. Criteria for salinity zones followed Parker (1965): fresh to 

 brackish (0 to 5 o/oo) ; low (5 to 10 o/oo) ; moderate (10 to 20 o/oo) ; and 

 high (greater than 20 o/oo). 



Relative and seasonal abundance entries are intended to give a broad 

 idea of temporal and spatial patterns. In many instances they refer back 

 to habitat information (e.g., locally abundant). Virtually no reliable data 



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