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 9 0 THE CONDOR [ VOL. V bers. Along .the balks of streams, such as the San Joaquin and Kings River and a few smaller creeks where moisture was plentiful and trees and plants abundant, birds thrived and the avifauna was about the same as that o[ the lower mountain districts. But in many places no such stream existed within a radius of less than ten or fifteen miles. Scarcely a tree or living shrub existed any nearer; and birds or any inhabitants would have to be such as could adapt themselves to such bar- ren conditions. During the summer months the long absence of rain dried the alfilliria so that the country was almost desolate in appearance. The level of the plain was broken occasionally by winding, shallow depressions, called by the settlers "sand hollows." These by some are said to be the remains of old water courses. The influence of irrigation has brought ,the underground water so near the surface that the "sand hollows" have been transformed into extensive ponds which are the reproductions in minature of the old Tulare Lake. The same cause, irrigation, from which Tu- lare lake nearly went dry a few years ago, has filled these dry hollows with water and they are now teeming with all the varied forms of plant and animal life once found along its shores. The burrowing owl, one of the most prevalent species formerly, is now becom- ing extinct wherever the country is thoroughly cultivated. These owls live and nest in the discarded burrows of squirrels, and the plentiful irrigation, which, in time, drowns out the squirrels, is far more fatal to the owls. The nightly "cuckoo" of these birds is seldom heard wherever the.country is intensively cultivated. The meadowlarks also are far from being as plentiful as they once were, for the same causes which are exterminating the owls make nesting a very difficult and uncer- tain matter for the ground-nesting larks. It may be said that the advent of orchards and vineyards and the multiplica- tion of other conditions upon the plains favoring the lives of many other birds, has caused the bird population along the streams and in the foothills to overflow into this new territory. The population in some districts has increased extensively .and a few species have increased to such an extent as to become a positive nuisance to the fruit growers at certain seasons of the year. The migrations through the valley are of separate interest. During the win- ter months birds of the higher mountain districts are often seen upon the plains. However, it can hardly be said that the new conditions influence the migration of birds to any degree. An abundance of spring migrants arrive every year, but in all probability they are the same species which formerly came every spring to the more favorable localities of the valley. A Morning With the Birds of Juan Vinas, Costa Rica BY MERRITT CAR rHILE in Costa Rica last year with Prof. Lawrence Bruner and M. A. Car- riker, Jr., of the University of Nebraska, 1 secured a number of bird notes which I thought might be of interest to CONDOR readers. For three weeks we had been collecting at the Estancia Jimenez, far up on the southeast slope ot the Volean Irazu, and in Monte Redondo, a mountainous