Probably due to the droughts, wherein the normal amounts of fresh water that would normally be entering the Gulf from the rivers to help keep the water salinity stabilized. Also, with it being so hot out, maybe there are organisms growing in the "stew" of the Gulf. Both of those are just my best guesses and have no fact to back them up, but they sure do sound good!! :)
The dolphin may possibly have died following the cold water in Gulf, near Corpus Christi in Texas. Dolphins cannot bear the cold temperatures, especially during winter season which is the period for infants.
For years dolphins have been beaching themselves, normally it's Due to old age, disease, or premature dolphins . These dolphins beach themselves on the east coast ( remember back a few months, hundreds of dolphins beached themselves along the east coast) no one knows why the dolphins are beaching themselves along the gulf. Biologist are researching this new phenomenon. Happening in Corpust Christie. This was all I could find, hope it helps.