LiLiL* Wetmore, Birds of Lake Burford, N. Mex. [April 



Chama on June 19. Our stay at the lake extended over a period 

 of four weeks. 



Physical Features 



Lake Burford is located approximately at 7000 feet above sea 

 level and lies in a trough or depression extending north and south 

 near the summit of the Continental Divide. The lake covers an 

 irregular basin surrounded by rolling knolls, that around most of 

 the shore come down directly to the water. These are strewn with 

 loose fragments of sandstone and overgrown with sage. In sev- 

 eral places rocky promontories of yellowish white sandstone rise 

 abruptly from the water's edge. Near these the lake bottom is 

 hard and firm ; elsewhere it is composed of soft black mud that is 

 deep and treacherous. The shoreline in 1918 was between 15 and 

 17 miles in all, and the water surface extended over between 4 and 

 5 square miles. The northern end of the lake is broad and open, 

 while the southern part is cut by projecting promontories into sev- 

 eral small bays (Plate VII, fig 1). In the southern area are three 

 small islands. The depth of the lake in the center varied from 6 

 to 9 feet. Lake Burford receives its water supply from snow 

 water and rain, and to some extent from springs. In extremely 

 high water it may overflow from a narrow east bay down a great 

 cleft in the sandstone rock known as La Puerta Grande, that leads 

 down toward the Chama (or Brazos) River, but within modern 

 times the water content of the lake has not reached such a level. 

 There is, however, an underground flow here that feeds two small 

 lakes below the large one, and seepage continues on below these. 



The waters of Lake Burford are distinctly alkaline, though the 

 alkali is not concentrated, so that sheep, cattle and horses water 

 here without trouble. Where low flats bordered the shore a thin 

 alkaline scale or efflorescence formed on the surface of the mud, 

 and isolated pools in such areas were found to be strongly saline. 

 There was a decided difference in appearance in the water of the 

 northern and southern parts of the lake. That in the broad, open 

 northern portion was gray, murky and opaque, so that objects 

 four inches below the surface were barely visible. The water in 

 the southern end was clearer and contained less sediment, so that 

 bottom might be seen at a depth of three feet. This difference 



