Study of Post-larval Penaeid Shrimp Entering Aransas Bay - Study of Texas Shrimp Populations
Preliminary steps were taken to set up types of sampling that would capture post-larval shrimp entering bay nursery grounds through the ship channel at Port Aransas, Texas. Due to the rather meager number of post-larval shrimp keys available, identification was accomplished only to genus. Sampling of the channel bottom on February 20 produced penaeids of 12 mm. length. Sampling on March 27, both in the main channel and in flats along an adjacent channel, produced 288 post-larval penaeids, the greatest number taken during the sampling period. Samples through November produced few shrimp, excluding 50 caught on October 2. Mysids, hypoplanktonic crustacea living generally on or near the bottom, were numerous in the samples and displayed somewhat the same abundance pattern found for post-larval shrimp. February water temperature averaged 15 degrees Celcius, rising to 18 degress Celcius in March, with a general warming trend through the sampling period to 28 degrees Celcius in October. On the shallow sand flat sampled, salinity rose from 22 ppt in March to just above 30 ppt in April and remained fairly constant thereafter. At the channel bottom salinity stayed above 30 ppt.