(at the northern end of the range of the species), 

 Guaymas and Ahome Point in the Gulf of Calif- 

 ornia, Gulf of Fonseca, Gulf of Panama, and 

 Gulf of Guayaquil . Four meristic characters 

 were studied: vertebrae, dorsal fin rays, anal 

 fin rays and gill rakers. Vertebral counts were 

 made on 250 fish from each locality and other 

 characters were studied on 125 specimens from 

 each locality . Unlike the northern anchovy, none 

 of the meristic characters were found to vary 

 with sex. Only gill -raker counts increased in 

 number with increase in length of fish. 



A summary of the mean number of verte- 

 brae and fin rays for each locality follows: 



From a study of the number of gill rakers 

 on the first arch related to length, it was found 

 that fish from Almejas Bay, Guaymas and Panama 

 fall close to the average curve (all localities 

 combined) whereas Guayaquil and Fonseca 

 anchovettas have a smaller number of gill rakers, 

 and Ahome Point fish have a larger number. 



Considering all four meristic characters, 

 Howard concludes that three population groups 

 are indicated: (1) Almejas Bay, (2) Guaymas, 

 Ahome Point and Fonseca, and (3) Panama and 

 Guayaquil. He further postulates that the local- 

 ities within groups (2) and (3) appear to be 

 distinct from each other on the basis of gill raker 



The range in number of vertebrae was 

 found to be small, 39 to 43, and in all localities 

 the majority of anchovettas had 41 vertebrae. 

 Only one locality, Almejas Bay, was found to 

 differ significantly from the remaining localities 

 with respect to vertebral number. 



The dorsal ray counts ranged from 13 to 

 17, with over 70 percent of the anchovettas hav- 

 ing 15 fin rays. No difference was found between 

 localities. Anal fin ray counts ranged from 18 

 to 25 with most fish having 21 to 23 rays, but 

 with variation associated with locality. From a 

 comparison of the anal ray counts of each local- 

 ity with those from the other localities it was 

 concluded that two population groups could be 

 identified: (1) Guaymas -Ahome -Fonseca and 

 (2) Almejas -Panama -Guayaquil. The first group 

 represent adjacent localities; Almejas, on the 

 other hand, is widely separated from Panama 

 and Guayaquil and was shown to be distinct from 

 these in mean number of vertebrae. 



counts, hence the six localities should be con- 

 sidered provisionally to have separate stocks 

 of anchovettas. Although the analyses indicate 

 that there is not free interchange of anchovettas 

 between the six principal baiting areas, the 

 possibility of partial intermixing is not precluded. 

 To assess the extent of mixing, Howard suggests 

 that a tagging experiment on fish in all important 

 baiting areas should be undertaken. In the last 

 annual report of the Inter-American Tropical 

 Tuna Commission (annual report for the year 

 1954), a summary is given of a tagging experi- 

 ment in the Gulf of Panama . About 5,000 ancho- 

 vettas were tagged during 1954, of which 5 have 

 been recovered subsequently, all within the Gulf 

 of Panama . One recapture was made about 1 10 

 miles distant from the point of tagging. Tagging 

 has not been started as yet in other areas. 



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