Bradwell National Wildlife Area Management Plan: chapter 5

5 Management approaches

This section and Table 4 contain a description of all the possible approaches that could be used in the management of Bradwell National Wildlife Area (NWA). However, management actions will be determined during the annual work planning process and will be implemented as human and financial resources allow.

^d Level of Priority:
(1) = from 0 to 3 years
(2) = from 4 to 6 years
(3) = from 7 to 10 years

5.1 Upland habitat management

Grazing and fire will be used to create diversity in the structure and composition of the plant community at Bradwell NWA, thereby improving the wildlife habitat. Greater variety in the structure and composition of perennial upland cover is known to support a greater diversity of species relative to a monoculture or uniform harvest system (Askins et al. 2007; Rotenberry and Wiens 1980). For example, waterfowl nest density and success appears to increase on landscapes with many small wetlands and a patch-work of idled and managed perennial hay and annual cropland (Arnold et al. 2007). Some species, such as Northern Pintail, may benefit from haying or otherwise managing perennial cover (McMaster et al. 2005). Thus, new management interventions could be used to achieve the goal of improving wildlife habitat.

5.1.1 Prescribed burning

Prescribed burning may be undertaken in any year to reduce the cover of invasive native shrubs, alien perennial grasses, or litter build-ups that are otherwise considered a fire hazard. A cumulative total of 43 hectares (50% of the uplands) will be burned in each 5-year period, such that the average fire return interval on the upland grasslands is 10 years; this return interval is consistent with natural fire regimes in this region (Wright and Bailey 1982). To minimize short-term negative effects on migratory birds, burning will be restricted to early April before the nesting season begins, or September and October after the nesting season has ended.

Burn units will focus on restoring remnant native grasslands and maintaining planted native grasslands, in association with livestock grazing. Boundaries of burn units will include constructed features like trails and ditches, or open water bodies, and mowed fire-guards that follow property edges or ridge- tops. These boundary features either offer discontinuities in fuels, ease of equipment access, or are otherwise effective lines for ignition of backfires that will travel slowly downslope. Backfires from these boundary features will be the primary form of ignition, with strip fires or head fires used only where a black line or water body 10-15 metres in width occurs downwind and around the flanks. Burns will not be conducted where wind speeds exceed 25 km/hr, to reduce the risk of long-distance ember transport from woody fuels or the risk of fires jumping fire guards (Cheney and Sullivan 2008). Individual burn units will be designed to safely manage each fire with existing numbers of appropriately trained staff. Finally, burns will not occur during periods of fire bans dictated by surrounding municipal or provincial governments.

Other procedures respecting occupational health and safety training requirements, pre-burn checklists, incident command system, post-fire mop-up, and cooperation with surrounding land owners and municipal fire departments will be outlined in individual burn plans.

5.1.2 Livestock grazing

Grazing by domestic livestock can diversify the structure of perennial cover at Bradwell NWA and limit weeds and woody plant invasions. Thus, grazing will be an important tool for maintaining ecological integrity of the Bradwell NWA and providing more heterogeneity in nesting cover for a greater diversity of birds. Two components of implementing a livestock grazing regime include designing the regime most appropriate for the ecosystem and then constructing the infrastructure needed to support that regime. Grazing regimes are described by timing, duration, frequency, and stocking density. Grazing rotations involve the movement of animals from one pasture to another, deferment involves delaying grazing in a pasture until most plants have completed seed production or nesting is completed, and rest involves not grazing a pasture for at least one year (Heitschmidt and Stuth 1991).

Bradwell NWA will be managed with grazing deferred to summer and fall (after July 15), at a moderate stocking density, to maintain productivity and density of the grass cover for nesting waterfowl. Burns in patches of remnant native grasslands may help target grazing of Smooth Brome there in July. The estimated maximum stocking rate for Bradwell NWA is 167 animal unit months (AUMs), assuming average climate conditions and tame grass dominance on 77 ha of sandy, dark-brown uplands, and 15 ha of dark-brown wet meadows (see Thorpe 2007 for methods). Actual stocking rates between 2008 and 2012 have varied from 299 AUMs in 2008, 173 AUMs in 2009, 91 in 2010, 39 AUMs in 2011, 0 AUMs in 2012, and 122 AUMs in 2013. The impacts from over-utilization in 2008, including creation of deeply rutted trails, were still visible in 2012. Actual grazing seasons have also varied from August to October.

5.1.3 Herbicide application

Control of new invasive alien species or weeds identified as noxious under the Saskatchewan Weed Control Act will employ chemical formulations and application timing prescribed by licensed pesticide applicators. Control will be done up to 30 metres inside the NWA boundaries to promote compliance with the act above. All application methods will involve hand-held or all-terrain vehicle ATV-mounted equipment to minimize disturbance to surrounding vegetation. Spot-spray applications of broadleaf herbicides with limited residual effects will be used to target patches of the major problem species, like Canada thistle or absinthe. In all cases, no follow-up revegetation actions should be necessary, except for monitoring the success of actions and re-application where first efforts failed.

5.2 Wetland habitat management

Wetland habitats naturally fluctuate with changes in water level. Temporary ponds are frequently dry by mid-summer or completely dry in half the years over a two decade period (Stewart and Kantrud 1971). Changes in water level are driven by two primary factors: climate and land management. Only in the area of land management can wetlands be indirectly managed, by controlling the amount of runoff or groundwater seepage entering the wetland basin. Inputs associated with land management may also influence water quality through sedimentation, increased turbidity, and eutrophication. Thus, the grazing and burning proposed in Section 5.1 will inevitably affect the wetlands, by increasing runoff while decreasing infiltration and transpiration. That runoff will also contain organic and mineral nutrients in ash and livestock wastes. These are natural disturbances in this ecosystem and may be essential sources of dissolved organic carbon for biological activity in wetlands.

Water quantity and flow manipulations are not generally desired for habitat management, as artificial reservoir filling or wetland drainage are known to have adverse environmental effects on some wildlife and wildlife habitats (Murkin 1998; Bartzen et al. 2010). Because the NWA is a federally protected area, conservation of wildlife and wetland function are legal or policy expectations. However, the directed management of wetlands in the Baldwin Project are intended to benefit waterfowl, particularly broods in mid-summer, when natural water supplies may be limiting to brood survival. Because Bradwell NWA was originally created to protect the water quantity and flow control infrastructure for DUC, the water flow and quantity infrastructure will thus be maintained in order to sustain the function of the manipulated wetlands.

Maintenance may include frequent inspection and operational visits by DUC staff, and occasional heavy equipment access, soil excavation and replacement, dredging and clearing of ditches, metal culvert replacement, and revegetation of disturbed sites. These activities should be consistent with the Federal Policy on Wetland Conservation, and are not likely to result in significant adverse environmental effects under the Canadian Environmental Assessment Act, 2012. Regulatory matters regarding the removal of water from the canal system are under the control of the Saskatchewan Water Security Agency, which issues permits to DUC for this purpose.

5.3 Wildlife management

Hunting is allowed on Bradwell NWA by a notice posted at the entry to the property. It was waterfowl hunters who financially supported the DUC Baldwin Project, with the intent that waterfowl hunting would be allowed in the area. All federal and provincial wildlife hunting regulations apply on Bradwell NWA.

Occasional removal of beavers or muskrats will be permitted where those animals are responsible for plugging water control structures or back-flooding municipal roadways. Humane removal methods of the animal, lodges, and any dams, as well as follow-up prevention methods, will follow the direction of a provincial conservation officer and any applicable provincial legislation.

No other active wildlife population management is anticipated for 2014-2018.

5.4 Multi-agency land management partnership

The primary function of Bradwell NWA is to protect water control structures constructed by DUC and which feed wetlands beyond the boundaries of Bradwell NWA and into the larger DUC Baldwin Project. When considered together, Bradwell NWA and the DUC Baldwin Project provide important habitat for a nationally significant concentration of migratory waterfowl species, consistent with the Protected Areas Strategy (Environment Canada 2011b). A multi-agency land management partnership, where Bradwell NWA is consolidated with adjacent DUC properties under a single management authority led by Environment Canada, is one possible way to address the above inconsistencies and was recommended in the last management plan for Bradwell NWA (Canadian Wildlife Service 1985). With this option, conflicting needs of downstream water users may be reduced, and water resources may be managed for a broader range of wildlife, which is more consistent with Wildlife Area Regulations. In addition, expansion of the Bradwell NWA land base and wetlands would attract a more significant concentration of migratory bird species and numbers, which are more consistent with the criteria for selection and retention of a National Wildlife Area. A second option involves a cooperative management agreement with DUC to jointly manage Bradwell NWA and the surrounding DUC Baldwin Project.

Feasibility assessment of the two options above requires open communication between CWS, DUC, the Municipality of Blucher, Saskatchewan Ministries of Agriculture and Environment, and landowners surrounding Bradwell NWA, so that options for consolidation of ownership and management or further cooperation can be discussed. Communication between interested parties is the first step in assessing the ecological and socio-economic dimensions of the potential expansion of Bradwell NWA onto adjacent privately-owned properties.

5.5 Monitoring

The following monitoring activities will be conducted at Bradwell NWA to evaluate the management goals and objectives and to meet any species at risk recovery strategy or action plan objectives. As stated previously, all monitoring activities will occur within limits imposed by the financial and human resources available.

1. Distribution and abundance of waterfowl, songbird species and species at risk (Goal 1.a-c, 2.a).
2. Upland habitat suitability for grassland songbirds and prairie ducks, particularly Sprague’s Pipit and Northern Pintail, using vertical obstruction and foliar cover measures for comparison to published habitat needs (Goal 1.a-c,).
3. Distribution and abundance of native plant species (Goal 1.a-c).
4. Distribution and abundance of alien invasive species (Goal 1.c).
5. Rangeland and riparian (lentic) health assessments where lands are grazed by livestock, including before and after measurements with associated control and impact sites (Goal 1.a-c and 2.a).
6. Woody vegetation reductions in response to burning treatments, using height and density measures, including before and after measurements with associated control and impact sites (Goal 1.a, 1.c).
7. Noxious weed reductions following control methods employed, using cover, area or density measures appropriate to the target weed, in the year controls were applied and the year following (Goal 1.b).
8. Aquatic habitat quality for waterfowl, using submergent vegetation and Fathead Minnow abundance as indicators of acrolein or canal water inputs at control and impact sites (Goal 2.a.).
9. Adherence of permittee(s) and DUC to prohibited activities and permit conditions (Goal 1.a-c, 2.a-c).
10. Condition of facilities and infrastructure for consideration of repair, replacement, or decommissioning on an annual basis (Goal 1. a-c, 2.a-c).

Results of the above monitoring activities will be considered in annual and ongoing management planning for Bradwell NWA. Changes to monitoring activities may be made following the five-year review of the management plan and management goals.

5.6 Research

Research activities will be considered for permitting when the results obtained through research have the potential to:

1. Address one or more of the management goals/objectives;
2. Not interfere with the conservation of wildlife; and
3. Not be likely to cause significant adverse environmental effects.

To obtain a permit to conduct research in Bradwell NWA and to receive instructions concerning guidelines for a research proposal, please contact:

Protected Areas Ecologist
Environment Canada, Canadian Wildlife Service
Prairie and Northern Region
115 Perimeter Road,
Saskatoon, Saskatchewan, S7N 0X4

5.7 Public information and outreach

Few people visit Bradwell NWA for wildlife viewing or waterfowl hunting, and a substantial program for public information and outreach is not warranted. For national and international audiences, summary information is made widely available through Environment Canada’s Protected Areas website. For local audiences, boundary and information signs are vital for maintaining awareness of the site. Local audiences and outcomes to consider when preparing any communications materials or events, include:

• permitted agricultural users, hunters, or maintenance contractors that comply with all permit conditions or posted notices; and
• adjacent neighbours who can promptly report suspected contraventions of prohibited activities to CWS.

Since local users are most likely to impact Bradwell NWA, it is important to build local support for NWA management goals and objectives. It is reasonable to expect continued levels of local support and compliance with prohibited activities, given the fact that current management includes grazing with locally-owned livestock, permitted hunting, and permitting of the occasional removal of problem beavers.