NATURAL HISTORY OF REDFISH, ETC., OF TEXAS 



135 



semidry mud or sand flat, which extends south to a point about 30 miles above Point 

 Isobel, Tex. Consequently, very little circulation of water occurs in the vicinity of 

 Baffin Bay. The only sources of fresh water are the small creeks emptying into the 

 bay, and of salt water, the drift of sea water from Corpus Christi Pass and Bay 

 southward. With little rainfall on this particular section of the coast, the salt water 

 predominates nearly all the year in and about Baffin Bay as well as in the more north- 

 ern portions of the lagoon. 



During the summer of 1925 a period of excessive sahnity (indicated by high 

 specific gravity of the water) occurred in Laguna Madre, which caused severe mor- 

 tality of fish trapped within the lagoon on account of the nearly dry areas between 

 the section of high salinity (Baffin Bay) and the deeper, less saline waters of Corpus 

 Christi Bay and the Gulf of Mexico. Table 1 presents a series of specific-gravity 

 determinations within the particular area of high salinity as well as within other 

 bodies of coastal water not aft'ected. In all, 185 determinations were made throughout 

 the area covered in Figure 1, but only the major stations have been given in Table 1. 

 Waters with a low saline content are denoted by low specific gravity (Nueces and 

 Copano Bays), while waters with a high content of salts are indicated by high specific 

 gravities (Baffin Bay and Laguna Madre). Ordinary Gulf water found about the 

 passes has generally a specific gravity of about 1.026. During July and August, 1925, 

 the specific gravity of the water in Baflan Bay and lower Laguna Madre reached 

 1.055 — twice that of normal Gulf water near the passes. 



Table 1. — Excessive salinity of the water in the vicinity of Baffin Bay and Laguna Madre, Tex., during 



the summer of 1925 



[The specific gravities indicate the relative salinity in various coastal waters. Ordinary Gulf water has a specific gravity of about 

 1.026. Consult text for details. Determinations by H. F. Prytherch] 



Date 



July 29 

 30 

 31 

 31 

 31 



Aug. 4 



12 

 12 

 13 

 14 

 14 

 14 

 14 

 15 

 15 

 Sept. 3 

 3 

 i 



Locality 



Specific 

 gravity, 

 17.5° C. 



Baffin Bay - 



Laguna Madre 



Corpus Christi... 



Corpus Christi Pass... 



Corpus Christi Bay by Oso. 



Corpus Christi Bay 



Aransas Bay 



Copano Bay 



Baffin Bay 



Laguna Madre 



do 



Corpus Christi Pass.. 



Corpus Christi Bay by Oso 



Nueces Bay 



Aransas Pass 



Aransas Bay 



Copano Bay 



Baffin Bay 



Laguna Madre. 



Corpus Christi Pass 



Water 

 tem- 

 pera- 

 ture" F. 



1.055 

 1.055 

 1.029 

 1.027 

 1.028 

 1.028 

 1.025 

  1. 021 

 1.055 

 1.060 

 1.055 

 1.028 

 1.027 

 1.023 

 1.028 

 1.026 

 1.023 

 1.055 

 1.044 

 1.029 



87.0 

 87.0 

 84.0 

 85.2 

 86.0 

 83.0 

 81.7 

 82.7 

 86.0 

 87.0 

 86.0 

 87.0 

 86.0 

 88.0 

 86.0 

 85.0 

 86.0 

 88.5 

 88.0 

 86.0 



Air 

 tem- 

 pera- 

 ture °F, 



86.0 

 84.5 

 84,0 

 82.6 

 86.0 

 82.5 

 81.0 

 84.0 

 88.0 

 84.0 

 87.0 

 81.0 

 88.0 

 84.0 

 83.0 

 82.5 

 85.0 

 86.0 

 87.0 

 83.5 



Date 



Sept. 



Oct. 



Locality 



Specific 

 gravity, 

 17.5° C. 



Water 

 tem- 

 pera- 

 ture °F. 



Corpus Christi Bay by Oso. 



Nueces Bay 



Aransas Pass 



Aransas Bay , 



Copano Bay 



Baffin Bay.. 



Laguna Madre 



Corpus Christi Pass 



Corpus Christi Bay by Oso 



Nueces Bay 



Aransas Pass 



Aransas Bay 



Copano Bay — 



Baffin Bay 



Laguna Madre 



Corpus Christi Pass 



Corpus Christi Bay by Oso 



Nueces Bay 



Aransas Pass 



Aransas Bay 



1.029 

 1.023 

 1.027 

 1.027 

 1.023 

 1.055 

 1.055 

 L030 

 1.029 

 1.020 

 1.027 

 1.024 

 1.024 

 1.039 

 1.039 

 1.026 

 1.024 

 1.017 

 1.025 

 1.021 



80.0 

 84.0 

 84.0 

 80.0 

 84.0 

 84.0 

 85.0 

 85.0 

 86.0 

 87.0 

 84.0 

 84.0 

 84.0 

 83.0 

 85.0 

 81.0 

 83.0 

 84.0 

 83.5 

 81.5 



Air 



tem- 



pera- 



ture°F. 



83.0 

 82.0 

 83.0 

 78.0 

 90.0 

 83.0 

 84.0 

 85.0 

 86.0 

 86.0 

 80.0 

 84.0 

 82.5 

 80.0 

 82.0 

 84.0 

 81.6 

 82.0 

 83.0 

 79.0 



The average precipitation at Corpus Christi for May, June, July, and August, 

 1925, was but 1.26 inches, compared with the normal average for these months of 2.38 

 inches. This reduction of nearly one half of the normal rainfall during the summer of 

 1925 accounts, at least partially, for the excessive salinities that prevailed in Laguna 

 Madre. Table 1 indicates a falling specific gravity within Baffin Bay and Laguna 



