1990. It appeared that the mortality was within the prior 4-year average by the end of May, 

 1990. A total of 344 stranded bottlenose dolphins were recovered along the U.S. Gulf coast 

 during January-May, 1990. Investigators from Texas recovered 159 strandings during this 

 period, while strandings recovered in the other Gulf states ranged from 42-52. Strandings by 

 state and month are shown in Table I. Overall, the number of reported strandings for 

 January-May, 1990, in the U.S. Gulf of Mexico was about 2.5 times the 1986-89 average for 

 those months. By comparison, during the 1987-88 U.S. Atlantic coast dieoff over 700 

 bottlenose dolphins were reported stranded over a 10-month period and represented a 10- 

 fold increase over the prior 4-year average in strandings. 



Between Januaiy-May, 1990, most of the dolphins recovered on a state by state basis 

 during the investigation stranded along the Texas coast. Approximately 166 dolphins were 

 reported stranded there from January- June, and 163 were recovered. Within January-March 

 and all states, the greatest number of recovered animals were from the Texas coast during 

 March (59), with January and February totals (also from Texas) of 42 and 40, respectively. 

 The totals for these months were the highest on record. Texas strandings for January were 

 4.4 times the 1986-89 Texas monthly average, February 2.3 times average, and March 1.5 

 times average. The cumulative Texas total for January-March, 1990, was 2.1 times average. 

 However, the Texas stranding recovery rate decreased after March, 1990, and Texas 

 strandings for April, 1990, were about 50% of average and the lowest total for April since 

 1986. 



A total of 204 animals were recovered from January-June along the coasts of the 

 other Gulf states. These represented about 55% of the recovered strandings for that period. 

 A total of 57 dolphins were recovered in Mississippi, 52 in Florida, 48 in Louisiana, and 46 

 in Alabama. By month, most (24) of the Mississippi strandings were recovered during March, 

 most (12 each) of the Florida strandings during February and March, most (27) of the, 

 Louisiana strandings during April, and most (12) of the Alabama strandings during March. 

 Recovery effort in 1990 in Mississippi and Florida was relatively constant, but the stranding 

 recovery effort along Louisiana was not, because of USCG supported helicopter beach- 

 surveys conducted during March and April, 1990. Stranding recovery effort along the 

 Alabama coast was consistent January-March. Alabama stranding recovery efforts increased 

 significantly during the last half of April, primarily due to Greenpeace efforts to increase 

 stranding reporting and recovery along the Alabama coast. 



It is likely that the effort expended on reporting and recovering of strandings was not 

 consistent between 1986-89 and 1990. The mass stranding of bottlenose dolphins in 

 Matagorda Bay, Texas during January 1990 was well publicized in Texas. The 1987-88 mass- 

 mortality of bottlenose dolphins on the east coast likely sensitized stranding networks and 

 various groups to strandings. The observed increase in stranding reports could thus be an 

 artifact of the influence of these events on reporting and recovery efforts. 



The results of regular, controlled effort surveys for marine mammal and sea turle 

 strandings along the Texas coast provided a basis for obtaining an independent measure of 



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