available to waterfowl. As waterfowl season progressed, water levels within semi-impoundments 

 were reduced to the maximum extent possible without preventing hunter access. In addition to 

 making aquatic vegetation more available, reduced water levels helped to maximize optimal dabbling 

 duck feeding habitat (depths of 5.1-20.3 cm). 



Ditching 



In 1975, personnel at LPWMA began planning a tranasse network in each of its nine semi- 

 impoundments. Existing tranasses and borrow pits were used when possible. The following goals 

 were used to plan the construction of new tranasses: 



(1) to provide access for hunting, fishing, trapping, and monitoring even during low water 

 periods; 



(2) to increase diversity for wildlife and fish populations; 



(3) to provide travel corridors for estuarine organisms in order to maximize use of semi- 

 impoundments; 



(4) to provide fire breaks during controlled burns; and 



(5) to facilitate water exchange during drawdowns and flooding. 



Tranasses were dug 8 ft wide and 6 ft deep by a marsh machine (dragline mounted on 

 pontoons). Tranasses provided sufficient depth to allow mudboat access during spring and summer 

 drawdowns. Spoil deposits were staggered to maintain water flow patterns. 



Periodic maintenance of tranasses was done every 3-4 years to remove encroaching vegetation 

 and silt deposits. Tranasse maintenance was accomplished by a marsh machine using a pipeline 

 backfill blade. Use of the backfill blade was found to be more efficient than use of a dragline 



bucket. 



Controlled Burning 



A common management technique practiced at LPWMA was controlled burning. This was 

 usually done in February or March following the fur trapping season. The primary purpose was 

 to retard plant succession and stimulate growth of wildlife food plants. The decision to burn was 

 made when climax species dominated large areas, when dead or dying vegetation was abundant, or 

 when undesirable vegetation grew. Burning was conducted on a 3 or 4 year rotation depending 

 on vegetative condition. Sections within each semi-impoundment were burned with water bodies 

 and tranasses serving as natural fire -breaks. Several unburned areas were left in each semi- 

 impoundment to provide food and cover for furbearers and other wildlife during the revegetation 

 process. 



Fires were set by personnel using matches or a torch while traveling in a boat. Backfires were 

 set around duck blinds, pumping stations, water control structures, and other fire sensitive areas. 

 Extreme caution was taken to insure the safety of humans and property. 



Trespass Control of Property 



During the early years of LPWMA, it was imperative that trespass control of the area be 

 established. Daily patrols were initiated to inform anglers and other individuals that LPWMA and 

 its waterways were closed to the public. Public notice for closure of the property was included in 



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