Mammals in NTEX 



In NTEX eight taxa were sighted a total of 28 times during August (Table 8). In 

 the same subunit during November surveys, only three taxa were encountered for a total 

 of nine sightings. Sperm whales, striped dolphins, spinner dolphins, spotted dolphins, 

 unidentified Stenella, and saddleback dolphins were sighted during August but not 

 November. The only taxon sighted during November surveys of NTEX and not 

 encountered during August was an unidentified whale sighted with a group of bottlenose 

 dolphins. This individual was medium in size, but could not be identified more 

 precisely. Dolphins composed 95.9% of the mammal fauna during August and 88.9% 

 during November. Bottlenose dolphin groups composed 37.0% of the dolphin sightings in 

 August and 87.5% of such sightings in November. Although the number of groups of 

 bottlenose dolphins sighted declined from 10 to 7 from August to November, other dolphin 

 species present in August were not encountered at all in November surveys. 



Mammals in NFLA 



The number of mammal groups sighted in NFLA was reduced by nearly 50% 

 (45.2%) during November in relation to August (Table 9). Three taxa were recorded 

 during November whereas seven were observed during August. Bottlenose dolphins 

 composed 45.1% and 58.8% of the August and November group sightings, respectively. 

 Although three groups of unidentified Stenella , (17.7%) were present in November, the 

 congeneric species (spotted dolphin and striped dolphin) were not identified. Considering 

 all species of the genus Stenella , November sightings were only 37.5% of those in 

 August. Saddleback dolphins, which represented 9.7% of the sightings in August were not 

 observed in November. 



Mammals in SFLA 



The number of sightings in SFLA (Table 10) was only slightly reduced, 14.7%, 

 during November in relation to August. This change was primarily the result of 

 differences in the number of sightings of pelagic dolphins of the genus Stenella : 11 (32.4% 

 of the mammal fauna) during August and 5 (17.3%) during November. In contrast to 

 dolphin populations in both northern subunits, bottlenose dolphins in SFLA were sighted 

 more frequently in November than in August. The appearance of a single manatee in the 

 coastal margin of SFLA in November may be related to the season or to local movements 

 in response to other factors. Manatees were present during both months but were not 

 commonly seen due to the inshore habits of this species (Irvine et al. In press). 



Of the four survey subunits, only in SFLA were all taxa that were encountered in 

 August, also recorded in November. Other subunits showed more conspicuous reductions 

 in the frequency and diversity of sightings. Both STEX and SFLA surveys during 

 November resulted in increased sightings of bottlenose dolphins. The absence of records 

 for sperm whales, saddleback dolphins, and Stenella species in Texas survey subunits 

 during November is noteworthy. Less conspicuous but parallel reductions occurred in 

 Florida. 



Birds in STEX 



Table 11 presents relative frequencies of birds in the STEX survey subunit. Bird 

 sightings were more frequent during November than August (190 vs. 122 records). Terns 



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