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Develop monitoring and evaluation methods to document population responses of other wildlife to habitat and management for waterfowl, and incorporate those methods into PPJV monitoring and evaluation plans.

Directed Studies

Evaluate in each state all waterfowl management practices for potential adverse effects on other wildlife, especially those targeted under Objective #2. Determine means of avoiding, offsetting, or mitigating these effects to ensure at least a neutral cumulative effect.

Models/Surveys

Obtain, and where practical, develop information on population limiting factors and population responses to waterfowl habitat development and management actions for species to be managed under Objective #2.

Support development of quantitative population objectives by agencies and organizations with management interests and responsibilities for other species of wetland dependant wildlife and other declining wildlife endemic to the PPR.

Predator Management

      Exclosures

Exclosures are designed to separate nesting hens and nests from ground predators. Electric fences are the most commonly used barrier. Exclosures represent an intensive management effort that requires initial expense and regular maintenance throughout the nesting season. Mallards and gadwalls are the primary duck species attracted to fenced areas, but other species of birds, including non-waterfowl migratory birds, also benefit. A density of 1 - 2 duck nests per acre should be targeted.

   Location

• Locate near good wetland habitat, preferably where 10 - 20 percent of the land within 1/2 to 1 mile of the exclosure is wetland.
• Within one-half mile of 60+ acres of semipermanent wetlands and as many seasonal wetlands as possible.
• Avoid fresh or slightly brackish permanent or semipermanent wetlands, stock dams, dugouts, and streams. Avoid building adjacent to areas to be fenced. These situations increase occurrences of mink. If unavoidable, place exclosure ≥220 yards from such mink habitat.
• Surrounding area (up to 1 mile radius) should have relatively poor nesting cover, and low nest success (use Mallard Model).
• Terrain inside fence should be level to gently rolling and soil should be high quality, and stable.
• Fenced area should be void of features that attract predators such as trees, rock piles, buildings, and wetlands.
• Secure brood travel cover should be available between exclosure and brood water. Small grain cover will usually be adequate (dense cover is likely not available if area is appropriate for fence).

   Size

• 20 - 80 acres. Areas less than 20 acres will probably not attract enough duck pairs to justify cost. It takes almost as much effort to maintain a 20-acre fenced area as it does an acre one.
• Exclosures should be 3 or 4 sided with no inside (concave) corners.

   Management

• Fences should be designed to allow deer to exit
• Establish dense cover with minimum residual Robel value of 1.5 decimeters. Cool season grass (such as intermediate wheatgrass/legume mix is suitable. Buckbrush and wild rose are also suitable cover.
• Close exclosure and remove predators just prior to nesting in spring. Use track sign to determine if predators are inside when gates are closed. Do not trap outside exclosure.
• Check fence and maintain predator control regularly (daily/weekly) through nesting season.
• Open fence at end of season to prevent prey buildup and to allow free access in and out by deer.
• In dry years consider that exclosures may not be worth maintenance effort.
• Consult Ducks Unlimited, Inc., or Service for fence design.

      Fenced Peninsulas

      Location

• For peninsulas > 5 acres in size located on semipermanent or permanent wetlands
• Brackish and alkaline wetlands are preferred
• Substantial pair and brood habitat nearby
• Other guidelines similar to stand-alone exclosures

      Peninsula Cutoffs

This treatment creates a water barrier that in essence converts a peninsula into an island. Gadwall, mallards, and blue-winged teal are the principal species nesting on cutoffs. Other duck species, such as pintail and lesser scaup, are found in lesser proportions.

   Location

• Select large brackish or alkali wetlands because they are likely to have low use by raccoons and mink (cutoffs are not 100 percent predator proof).
• Near ≥60 acres semipermanent brood wetlands with emergent vegetation and large numbers of seasonal wetlands within 1/2 to 1 mile to attract pairs.
• Where surrounding attractive nesting cover is minimal.
• Cut-off channel should create ≥100 yard water barrier with trench not deeper than surrounding bottom, but not less than 2 feet.
• Slope edge of trench to not create a cut-off bank that attracts muskrat and consequently mink.
• Avoid areas with substantial emergent vegetation near cut-off.

   Size

• Peninsula size is site specific, but because of expense > 5 acres is recommended.

   Management

• Trap peninsulas annually just prior to nesting season and check occasionally (search for tracks) to see if predator removal was complete.
• Establish nesting cover with Robel value of 1 - 1.5 decimeters if existing cover is inadequate. Brush type cover is suitable and should require no annual maintenance. Seeding grass/legume cover in winter when construction is completed has worked well.
• Remove trees, tall shrubs > 1.5 m, rock piles, debris, etc., that may provide cover/attraction for predators.

Consult with Ducks Unlimited, Inc. or Service for techniques and specifications for creating cut-offs.

      Nest Structures

Properly designed nest structures provide nest sites for mallards that are secure from ground predators if properly placed. Hay bales may not provide adequate protection from raccoon and mink.

   Location

• In Class III (Stewart and Kantrud) or semipermanent wetlands. Semipermanent wetlands are preferred.
• ≤6 feet from emergent vegetation.
• Where water depth is 18 inches minimum (when wetland is at normal level).
• Avoid areas with trees nearby.
• Where the attractiveness of surrounding cover is marginal for duck nesting (cropland and grazed pasture dominate).
• Where nest success in existing cover is low.
• Areas with high density of wetlands and mallard pairs.
• No more structures than the number of mallard pairs in the area (maximum density = 1 per acre).

   Management

• Culvert type nest structures should be filled with soil to anchor in place and provide base for vegetative growth (culvert type structures are low maintenance compared to some other types).
• Baffle may have to be installed to allow mallard hen and Canada geese to co-exist.

For information on availability and installation of nest structures, contact Service, ND Game and Fish Department, SD Department of Game and Parks.

      Create Islands

Small, man-made islands provide secure nesting sites that are used particularly by mallards, gadwall, and lesser scaup. Other duck species and Canada geese will also use islands in lower concentrations. Some islands attract extremely large numbers of nesting ducks (> 30 nests per acre).

   Location

• Large (≥25 acres) alkali wetlands with water depth of about 2 feet (shallow depth minimizes construction cost).
• Where numerous wetlands exit in surrounding area to provide pair habitat and brood cover.
• Where nest predation in mainland cover is known or expected to be high.
• In areas where competing cover is minimal.
• Where a minimum water gap ≥100 yards from shore can be maintained.

   Size

• Generally, islands should be constructed at 3/4 to 1 acre surface area above water. Smaller islands have been made and used successfully by ducks, but are subject to more rapid loss due to wave and ice erosion than large islands. Islands are expensive to build, so only the most suitable sites should be used. In general, ten 1 acre islands are better than one 10 acre island from duck use and success standpoint.
• Numerous islands can be created in a single wetland but islands should be separated so they are within the breeding territories of more breeding pairs.

   Management

• Islands should be covered with a minimum of 4 inches of top soil and planted with vegetative cover (intermediate or tall wheat/legume mix is preferred). Shrubs such as buckbrush and rose require some effort to plant, but require little maintenance and are very attractive to ducks. Shrubs should be planted in small patches in the center of the island where grass/legume mix was purposely not planted.
• Visit islands annually in the spring and trap predators that are present. Maintain predator control through nesting season.
• Gulls can cause problems on some islands, but may be deterred by planting dense cover to eliminate bare areas.

Consult with Ducks Unlimited, Inc. or Service for information on construction techniques, permits, etc., that are involved in island creation.

      Manage Natural Islands

Natural islands occurring in wetlands often represent "ready made" secure nesting sites that are attractive to several duck species. While some islands are adequate "as is," most require some form of enhancement or management to obtain maximum benefits. These efforts can be costly, so prioritizing sites is important.

      Location

• Any natural island may have potential, however, certain characteristics may be associated with the greatest benefits; alkali - best, brackish, then freshwater.
• ≥100 yards from shore.
• Near good wetland complex with ample pair and brood habitat.

   Size

• One-tenth acre and larger.

   Management

• Each island is unique and may require different levels of attention.
• Establish cover on islands if it currently does not exist.
• Remove debris, trees, tall shrubs > 1.5 m, etc.
• Trap in spring to remove predators. Especially in wet years.
• Minimize human disturbance.

   Other

• Island characteristics will vary. Some islands may consistently be free of predators. Still, this needs to be determined and an annual visit is recommended. Island use by nesting ducks is extremely important for prioritizing efforts. Monitoring use will allow maximizing benefits per effort and provide information that can be used to identify other potential sites or management strategies.
• Some islands are suitable only in wet years when high water inundates connecting spit. Dry years may provide opportunity to "disconnect" islands from shore.
• The Habitat and Population Evaluation Team (HAPET) office will investigate the use of an automated system using remote sensed data and Geographical Information System techniques to identify and maintain a register of islands in the prairie pothole region.

      Skunk Control

Skunks are the primary nest predator in some areas. Skunks are easy to trap in early spring (April) and, when combined with other management effort, skunk removal can provide an extra margin of security for nesting hens.

   Location

• In areas where the predator community is simple and skunk densities are not extremely high (otherwise, alternate predators and adjacent skunk populations will quickly fill voids created).
• Target areas where coyotes are the primary canine predator as opposed to red fox.
• Concentrate effort near areas treated by other enhancement methods such as islands, planted cover, delayed haying, etc, or alternately implement a broad scale intensive effort over a large area (township, county).

   When

• Prior to whelping, April 1 to May 1.

      Red Fox Control

Red fox are a major cause of nest loss and kill many nesting hens in some parts of the Prairie Pothole Region of North America. Broad scale control of fox is generally not practical. However, special circumstances may warrant fox removal that benefit ground nesting ducks. Data should be collected to establish the effectiveness of the effort in each case.

   Location

• In areas where the predator community is simple and fox densities are not high.
• Near areas treated by additional enhancement measures such as on islands, delayed haying, planted cover, etc. This practice is probably beneficial only where fox densities are low or where complete control can be obtained.

      Coyote Management

Field studies indicate that areas dominated by coyotes will generally have higher nest success than similar areas dominated by red fox. Coyotes tend to displace red fox, yet coyote densities are usually lower in the areas they dominate (in the PPJV). It is not clear whether densities will increase as coyotes become better established.