Wood-duck nest box protected against furred predators 

 by the metal panel-type guard attached to steel post. 

 (Photo by F. C. Schmidt) 



ers would prefer a closed season; (3) determina- 

 tion of the most important reasons why hunters 

 fail to hunt during restrictive seasons; (4) a meas- 

 ure of the amount and success of hunting on 

 various types of land ownership has been under- 

 taken; and (5) an analysis of the 1962 controlled 

 whistling-swan season in Utah, now approaching 

 completion. 



Drawdowns and waterfowl use. — Studies at the 

 Patuxent Center have shown that low-value shrub 

 swamps and soggy woodlands characterized by 

 acid, dark-stained waters — such as occur through- 

 out much of the East and the Lake States — can be 

 cleared and shallow-flooded to form attractive 

 waterfowl breeding and feeding grounds. A bi- 

 ennial summer drawdown followed by fall reflood- 

 ing permits gernunation and production of over 

 50 species of useful waterfowl food and cover 

 plants in the mid-Atlantic region. Constant flood- 

 ing during alternate years provides breeding areas 

 for waterfowl and inhibits the establishment of 

 weed species. Operation of these units in pairs 

 insures that one pond is always flooded for water- 

 fowl utilization, even when the other is drawn 

 down. Over 90 nests and broods, made up princi- 

 pally of wood ducks, Canada geese, mallards, 

 hooded mergansers, and black ducks, were ob- 

 served in 20 impoundments totaling about 200 

 acres during the 1962 nesting season. "Wintering 

 flocks, consisting mostly of ring-necked ducks, 

 mallards, black ducks, and Canada geese, have 

 reached peaks of 2,000 in recent years. 



Aquatic plant studies. — The control of aquatic 

 plants, whether invading exotics or overgrowths 

 of native species, continues to be a major problem 

 in the management of waters for fish and wildlife. 

 An associated problem, although usually not so 

 troublesome, is the development of aquatic plant 

 growths on depleted and newly impounded waters 

 suitable for waterfowl and other aquatic wildlife. 



Alligatorweed. — Although rooted stands of alli- 

 gatorweed can be killed with granular formula- 

 tions of silvex, no herbicides have been found that 

 will give consistent control of floating mats. Lim- 

 ited success has been obtained from the application 

 of several chemicals on lodged mats during periods 

 of low water, if treatment is followed by freezing- 

 weather and a rise in the water level. 



l^lants that initiate their growth at thf same 

 t ime as alligatorweed are best able to compete with 

 it. Nearly half of the common plants assoriated 

 with allijratorweed on the Santee Refuge in South 



18 



