RED-THROATED LOON ( Gavia s tellata ) 



Sjtatus. --Fairly comipon spring and fall transient, and winter visitant 

 within 20 km of shore. Rare beyond 50 km from shore (Fig. 4). 



Normal p eriod of o ccurrence . --Late October to mid-Hay. 



Earliest fall r ecord . --14 November 1971. 



Latest spring record. --1 June 1975. 



Maximum counts .— SPRING: 16 in 1 h, 2-9 km offshore, 25 March 1973. 

 FALL: r4~Tn 1 h, 2-9 km offshore, 14 November 1971. WINTER: Although insuf- 

 ficient observation time was spent in the shallow zones which this species 

 frequents, 0-15 (x = 3.9) birds were observed in the 0-10 fathom zone (19 km 

 offshore) along 23 transects from December through March. 



Remarks . --Habits similar to common loon. However, Palmer (1962) noted 

 that the red-throated loon is more gregarious than the common, and several 

 hundred may gather at productive feeding areas in shallow waters. 



E 

 o 



^-» 



CO 



1000-1 



500 - 



100 - 



40- 



30 - 



20 - 



10- 







X 



X 

 X 



X 

 X 

 X 



X 

 X 



\iU 



J F 



1 r 



M 



1 1 1 1 1 r 



AMJ JASON 



a 



D 



month 



1=0.1-1.0 1=1.1-5.0 



MEAN NUMBER OF INDIVIDUALS OBSERVED PER HOUR 



X = ZONE NOT SAMPLED IN THIS MONTH 



Figure 4. Seasonal abundance and seaward distribution patterns of the red- 

 throated loon in the northern Chesapeake Bight, 1971-1977. 



10 



