SEVENTEENTH ANNUAL REPORT 87 



GROUND IMPROVEMENTS AND MAINTENANCE WORK OF THE 

 DEPARTMENT OF CONSTRUCTION AND FORESTRY. 



Hermann W. Merkel, Chief Constructor and Forester; E. H. Costain, 

 Assistant Forester. 



The most important work in permanent improvements 

 undertaken this year was the final development of Bird Valley, 

 from the Aquatic Bird House, southward to the Elk Range. 

 This was demanded by the completion of the Eagle and Vulture 

 Aviary, and the building of the Zebra House and Wild Horse 

 Yards. This work consisted of a great amount of filling and 

 grading. It required the hauling in of over 5,000 cubic yards of 

 earth, the construction of 5,826 square yards of tar-surfaced 

 macadam roads and yards, 1,058 feet of 88-inch wire fencing on 

 steel posts, and 664 feet of yard fencing of steel. The yard 

 fences were constructed wholly by our own force, and they cer- 

 tainly are highly creditable to Mr. De Wellsworth and his men. 



This yard fencing was erected on concrete copings, with 

 pipe posts. The panels consist of a combination of bars, small 

 mesh electric-weld netting, and hand-woven wire mesh. This 

 work furnishes six large outdoor yards for the Zebra House. 

 The large ranges west of this building were also fully developed 

 and completed, so that the entire hill is now occupied by the wild 

 equines, their three buildings and 13 corrals and ranges ad- 

 joining them. The total cost of all this work, including the 

 building of 42 catch-basins and the laying of 1,255 feet of 

 drain pipe was $13,900.00. 



Immediately westward of the Eagle and Vulture Aviary, 

 a series of eight show cages and fourteen breeding cages for 

 birds have been constructed. These cages were erected on con- 

 crete foundations, running 4 feet below the surface in order to 

 exclude all danger of rats. They have been built of steel and 

 %-inch mesh wire netting throughout and when fully completed 

 will cost about $1,200.00. 



In order to facilitate the cleaning of the Sea Lion Pool, 

 and greatly reduce the amount of water necessary for each 

 filling, the entire bottom of this pool was raised about three 

 feet. 



The unsatisfactory condition of the surface of the service 

 road, concourse and approach necessitated a certain amount of 

 grading and a surfacing of tar-macadam of all those roadways. 

 This included the service road from the Service Building to 



