The reaction of the grass shrimp, Palaemonetes pugio Holthuis (1952), to phenol in bio-assay and behavioral tests.




Matthews, G.A.

Journal Title

Journal ISSN

Volume Title


Texas A&M University.


The grass shrimp, Palaemonetes pugio (Crustacea; Decapoda), which is common in the estuarine marshlands along the Texas Gulf Coast, was shown to be a suitable organism for bio-assays and behavioral tests if certain precautions are taken. When tested in bio-assays with phenol, a common pollutant from industrial and domestic discharges and a component of petroleum, the shrimp showed a median tolerance limit of 28 ppm with a standard error of 1.28 for 48 hour tests and 50 ppm with a standard error of 1.26 for 24 hour tests. A toxicity threshold of about 10 ppm was also shown. In behavioral test the shrimp showed avoidance reactions to phenol solutions with sublethal concentrations down to 0.5 ppm. Shrimp also showed more avoidance of phenol while in stages of their molt cycle bordering ecdysis. Water samples from Galveston Bay and the Houston Ship Channel showed phenol concentration from 0.090 to 0.465 ppm +/- 0.070 ppm, clearly sublethal and barely strong enough to cause avoidance. Results of these tests support the hypothesis that escape as well as kill accounts for the lack of animal life in marshlands near industrialized areas and areas receiving toxic discharges and run-off waters.


56 p., Thesis


grass shrimp, toxicity, Palaemonetes pugio, bioassays, behavior