Managing Agricultural Lands Including Hayfields, Crop Fields, and Pastures for Grassland Birds
Author: Andrea Jones and Peter Vickery, Grassland Conservation Program, Center for Biological Conservation, Massachusetts Audubon Society, Lincoln, MA
This article was reprinted with permission of the author for use in the 1999 Niagara Frontier Forest Owners Workshop. Those interested in more detailed information on this topic should contact the Massachusetts Audubon Society at the address provided.
Note: The following material was excerpted from the publication Conserving Grassland Birds Managing Agricultural Lands Including Hayfields, Crop Fields, and Pastures for Grassland Birds. This and two others in the series (see references) are available through the Massachusetts Audubon Society, Lincoln, MA. (781) 259 9506 x7401 or by sending email to <email@example.com>.
This publication is available on the web from the Massachusetts Audubon Society at
< http://www.massaudubon.org/> and directly linked through
Conserving Grassland Birds by A.L . Jones and P.D. Vickery.. Set of 3 booklets: 1. Managing agricultural lands including hayfields, crop fields, and pastures, 17pp. 2. Managing small grasslands including conservation lands, corporate headquarters, recreation fields, and small landfills, 16pp. 3. Managing large grasslands including conservation lands, airports, and landfills over 75 acres, 17pp. Center for Biological Conservation, Massacheusetts Audubon Society, 208 So. Great Rd., Lincoln, MA 01773. ph. 781/259-9500.
A.L. Jones and P. D. Vickery. Conserving Grassland Birds Managing Agricultural Lands Including Hayfields, Crop Fields, and Pastures for Grassland Birds. Massachusetts Audubon Society. (781) 259 9506 x7401. Partial Reproduction with Permission.
Agricultural lands have provided home and sanctuary to grassland birds for many hundreds of years in the Northeast. In hayfields and pastures, birds such as bobolinks and eastern meadowlarks have raised their young, hunted for food, and returned each spring to continue this cycle. Many species of wildlife, including birds, mammals, and butterflies, adapted and expanded their population throughout the Northeast in the 1800's as land was cleared for farming.
Value of Farms to Birds
Most grassland birds use hayfields, meadows, and pastures for breeding while many other birds nest nearby and use crop fields and open areas for hunting and foraging. Some species nest along weedy borders and shrubby edges of fields and rely on open fields for feeding on seeds and insects. Songbirds, such as bobolinks and eastern meadowlarks, build nests on the ground, raise young, and forage exclusively within hayfields, meadows and pastures during the summer. In the fall, fields provide food for migrating sparrows, larks, and warblers. Some songbirds that breed farther north, such as snow buntings, visit farm fields in search of food during the winter months. Many hawks and owls, such as American kestrels, northern harriers, and short-eard owls, rely on grasslands of all sizes for hunting small mammals. Waterfowl and shorebirds frequently feed in flooded portions of crop fields during migration.
Value of Birds to Farms
Many birds that live in or near agricultural areas rely on farm fields, particularly for feeding. In many cases, they hunt the pests that can destroy or invade crops. For instance, American kestrels (small falcons) that are seen hovering over fields are searching for insects as well as small mammals. Red-tailed hawks, large common birds of prey seen perching atop trees in open country, hunt mostly for rodents as well as some birds and insects; large flocks are often seen following a plow as it churns up insects. Grassland birds also rely on insects such as caterpillars and grasshoppers found in the grasses to feed their young. They have all adapted to, and are an important component of , a grassland ecosystem.
Decline of Grassland Birds
In the past 100 years there has been a decline in the quantity and quality of grasslands for wildlife. In the Northeast, hayfields that were traditionally harvested late in the season provided ideal breeding habitat for birds. Today, most hayfields are mowed earlier and more frequently in the growing season or are planted in large single-crop fields. Changes in agricultural technology, movement of farms to the west, and an increase in human population in the Northeast have resulted in a decline of habitat for grassland birds. Because farmland has become fragmented, most remaining grasslands have become smaller and isolated and are no longer suitable for many species requiring large tracts of grassland.
Historically, the large grasslands in the Northeast provided habitat for many grassland birds, particularly the grasshopper sparrow, savannah sparrow, vesper sparrow, upland sandpiper, eastern meadowlark, and bobolink. However, as grassland habitat has become fragmented into small fields and pastures, only those birds that are adapted to living in smaller fields will persist at these sites. Bobolinks, eastern meadowlarks, and savannah sparrows are reliant on the remaining hayfields and pastures for their survival.
MANAGEMENT OF HAYFIELDS FOR GRASSLAND BIRDS
Mowing is central to many farming operations as well as the conservation of grassland habitats. The following suggestions can be used on hayfields to improve wildlife habitat while minimizing a reduction in the quality or quantity of hay harvests.
Keep alert for grassland birds nesting in fields. Mowing around areas where birds are frequently seen or leaving small patches unmowed can easily protect many nesting birds. Small unmowed patches will provide cover and feeding areas for birds for the remainder of the summer.
Rotating sizable fields (greater than ten acres) that are mowed early with those that are mowed late (hay used for bedding straw, etc.) Each season can provide some fields for nesting birds while minimizing an impact on high quality hay.
If possible, defer mowing until near the end of the grassland bird breeding season (i.e., after July 15) on fields not used for intensive hay production. This includes areas such as fallow fields, edge habitats, marginal farmlands and weedy areas.
Flushing bars can be used on haying equipment to move birds hiding in grass.
Avoiding nighttime mowing will reduce the risks of injuring roosting birds.
Raising mower blades to six inches or more may avoid crushing some nests and young.
Local bird clubs or conservation organizations can help determine where and what birds are nesting in hayfields. Careful observations can determine the approximate nest locations and when birds have successfully raised their young. (See Appendix 4 for a list of local Audubon/conservation societies to contact.)
Burning improves agricultural land by releasing nutrients into the soil. Burning, particularly useful in large grasslands, enhances native grass-species composition and eliminates the buildup of ground litter. Burning removes old grass stems, standing dead vegetation, and ground litter; controls plant diseases; and helps control the spread of exotic plants and woody vegetation. It encourages growth of native warm-season grasses and forbs (if already present in the soil) and improves forage plant quality and quantity. In addition, burning benefits most grassland bird populations within one or two years following a burn.
Burning in early spring (before arrival of birds in mid-May) is most beneficial to vegetation and nesting birds. Although some ground-nesting birds will not nest immediately following a burn, they will increase one or two years after a burn.
With large grasslands (greater than 100 acres), rotate portions burned over several years on a two- to six-year rotation, leaving some patches unburned each year (ideally burn 20 to 40 percent annually) to provide wildlife habitat and create a mosaic of vegetation.
Careful planning is necessary before burning. Most grassland burns occur between mid-March and the end of April, before greening and bird nesting. Timing of a burn must consider relative humidity, wind conditions and direction, air temperature and fuel conditions. Burn designs must incorporate existing firebreaks (roads, lakes, and streams), or fire breaks must be created. Adjacent landowners should be notified prior to burning. There may be state and local regulations governing controlled burns. Contact your local fire department for guidance and permits before burning.
MANAGEMENT OF CROP FIELDS FOR GRASSLAND BIRDS
Field edge conservation: Uncultivated shrubby or grassy and weedy edges, particularly along wetlands and streams, protect soils, control erosion, improve water quality, and provide wildlife habitat for a variety of birds, such as eastern towhees and song sparrows, nesting along edge habitats, as well as for foxes and other mammals. These areas are important to birds, butterflies, and mammals for feeding, cover and/or nesting. The Natural Resource Conservation Service's Wetlands Reserve Program may be able to pay for these areas to be protected (see page 7).
Brush row removal: Field borders, particularly those dividing fields, that are not needed for wind or erosion control, or to protect wetlands, can be removed to control invasive woody plants. This results in the creation of larger grassland habitats that are attractive to more species of grassland birds. Removal of woody vegetation can be achieved by a variety of means: mechanically, with herbicides, or by burning. Removal should be avoided during the nesting season to minimize wildlife disturbance. Areas where brush has been removed should be monitored for resprouting and regrowth. Repeat applications and spot treatment may be necessary for some resilient woody plants. Herbicides are applied directly to the newly cut shrub stem.
Cover cropping: Planting a cover of grasses, grains, or legumes in unused fields decreases soil erosion, increases organic matter and soil fertility, and provides cover and feeding areas for wildlife throughout the year.
Strip cropping: In large fields, alternating strips of grass or close-growing crops with cultivated crops, particularly on the edge of a field or along a drainage area, provides cover and nesting habitat for birds and other wildlife. Leaving these areas unmowed and ungrazed during the breeding season helps prevent runoff and erosion while providing areas for birds to successfully raise young.
Wetlands protection: Wetlands adjacent to crop fields are especially important for wildlife habitat, and surrounding buffers of natural vegetation aid in the breakdown of pollutants form agricultural runoff. Pollutants in runoff include nutrients in fertilizers and harmful bacteria and viruses in manure. The wider the buffer, the greater the reduction of pollutants. In fields that are in agricultural use, and where cultivation already occurs close to a wetland, a buffer zone of 20 feet will provide some water quality benefits. However, a buffer of 60 feet or more will make a greater contribution to controlling pollutants and should be the minimum wherever possible. For maintaining good wildlife habitat in a wetland, as well as controlling pollutants, a buffer of 300 feet is preferable. Decisions on the buffer will depend on the type of pollution, slope, soil type, vegetation and the value of the wetland as wildlife habitat.
Conservation tillage: Frequent tillage destroys nests and decreases shelter and food for wildlife. In addition, tillage buries roughly 75 percent of crop residues, including waste grains and weed seeds that provide food in the fall for migrating and grassland birds and waterfowl. Conservation tillage is defined as a tillage or planting system that maintains at least 30 percent of the soil covered by plants or plant residue. Decreasing tillage reduces soil erosion, saves fuel and time, conserves soil moisture, and improves wildlife habitat, but is associated with more frequent herbicide use.
Crop rotation: Rotating crops grown in each field helps maintain or improve soil productivity and fertility. This can reduce soil erosion from wind and water, helps control weeds, manages plant pests by breaking the pest cycle, and improves or maintains the condition of the soil. Crops planted in recurring sequence may include cover crops that provide habitat for wildlife.
MANAGEMENT OF PASTURES FOR GRASSLAND BIRDS
Planting fields in warm-season grasses, in addition to the more commonly planted cool-season grasses, can benefit both the farmer and wildlife.
Cattle, sheep and horses have different food preferences; their grazing has effects on the different vegetation structures of pastures. Many grassland birds in the Northeast tolerate and benefit form light grazing because it creates a mosaic of grass heights and structures, removes ground litter, and benefits bunch grasses. Light grazing also allows the development of wildflowers and scattered shrubs. However, intensive grazing leads to a loss of plant diversity and cover for wildlife.
Livestock rotation: Rotating livestock between forage fields planted in warm-and cool-season grasses prevents overgrazing and provides high-quality nutritious grass for a greater portion of the year. Manipulating the intensity , frequency, and duration of grazing in fields preserves upland or wetland vegetation, protects stream banks from erosion, minimizes soil compaction and benefits nesting grassland birds.
Spring burning: Burning pastures, particularly on poor soil, releases nutrients into the soil and encourages growth of nutritious, palatable grasses for livestock.
Creating a mosaic: Leavings some areas ungrazed and unburned each season and allowing grass to grow (8 to 12 inches) creates ideal habitat for growth of wildflowers, butterflies, and breeding areas for grassland birds. Maintaining adequate vegetation cover prevents soil erosion from wind and water.
Long-term agricultural benefits, including reduced soil erosion, decreased pollution of fresh water, decreased energy costs from fewer tillage operations, and increased soil fertility also provide farmland where grassland birds can thrive.
RESTORATION FOR WILDLIFE
Restoring portions of inactive farmland into grassland can be beneficial to the land as well as wildlife. Planting an area in grasses prevents soil erosion and runoff and increases the fertility of the soil. It is particularly beneficial in fallow fields or idle croplands that have been depleted of nutrients.
What to plant. Native grasses are recommended when possible to provide habitat for a diversity of wildlife. Grass species should be determined base on the following criteria: amount of rainfall, length of growing season, temperature extremes, and US Department of Agriculture Plant Hardiness Zones, in addition to soil conditions such as pH, water-holding capacity, aspect, fertility, drainage, salinity, and alkalinity. Soil maps, available from local Natural Resource Conservation Service (NRCS) offices, will help determine what types of native grasses are most suitable on your land.
Prior to planting, provide a firm, weed-free seed bed and uniform soil moisture to ensure that plants will not dry. Follow seeding specifications, such as planting depths, soil types, seeding rates, and fertilizer needs, set by the seed supplier or an agency such as NRCS.
Planting a mixture of grasses provides greater diversity for wildlife habitat. However, be sure grass species are compatible in the rate of establishment, maturity, and growth habits to ensure survival of all species planted and to create a uniform stand.
Where and how much to restore. Restoring areas of grasslands of 100 or more acres is ideal for wildlife habitat but not always practical. If possible, choosing an area to restore that is adjacent to other hayfields or meadows will create the effect of a larger continuous grassland system for wildlife. By restoring a large tract of grassland, or a small area surrounded by other grassland habitats, the amount and diversity of wildlife using the habitat throughout the year increases. Predation of grassland birds usually decreases as the size or amount of edge habitat of a grassland increases. Therefore minimize edge habitat where possible (circular or square fields are preferable to rectangular fields).
Restored areas of less than five acres that are not adjacent to other fields or open habitats may benefit wildflowers and butterflies, but such parcels will not likely be used by grassland birds. Bobolinks, having the smallest acreage requirements of any grassland bird, are not found nesting in fields smaller than five acres.
Sustainable agriculture is a widely used method of farming that protects agricultural land in a way that is beneficial to soil, water, and wildlife. Sustainable practices include the following.
Increased crop rotation on fields helps fields "rest" from crops that deplete the soil of nutrients and replaces fields with cover crops such as grains or grasses to prevent erosion and protect soil. This can provide habitat for wildlife.
Decreased use of pesticides protects water sources and associated aquatic wildlife form pollution and sustains greater insect populations in fields. Integrated Pest Management (IPM) is a program throughout the US that seeks to suppress pest populations to avoid economic losses while tolerating pest levels below economically damaging levels. This systems uses pesticides in smaller, localized dosages based on pest population monitoring, crop rotation to alleviate pests, and other methods such as 1) cultivating mechanically, 2) mulching, 3) planting pest-resistant crops, and
4) sanitizing fields. The release of beneficial organisms as pest controls is also considered part of IPM. Contact your state Department of Agriculture office for further information.
Conservation tillage protects ground insects and soil nutrients, and provides food and cover for wildlife.
PRESERVATION OF FARMLAND
In order to protect existing farmland and grassland habitat from development and to provide future habitat for farmland wildlife, there are several options to protect land, including the following.
The Agricultural Preservation Restriction Program (APR) has been instituted in most New England state to protect agricultural land from development. In this voluntary program, farmers apply to the state to sell development rights to their land. Farmers are compensated by up to 90 percent of the value of the land. In return, the state acquires the deed restrictions on the land, stating that the land must remain in some form of agriculture. This allows other farmers to buy farmland at affordable prices but restricts any purchases of the land for development. Contact your state Department of Agriculture office for information on this program.
The Conservation Reserve Program (CRP) was instituted in 1985 by the US Department of Agriculture (USDA). The purpose of this program has been to reduce crop surplus, protect soil from erosion, and increase wildlife habitat. As a result, habitat has been created and enhance for waterfowl and many grassland birds. Under this plan, landowners were paid to plant perennial vegetation (grasses, legume, or trees) on eroding of highly erodible fields. This land could not be grazed or harvested for a ten-year period. Over 34 million acres have been put into CRP since 1985. Although this program is not widely used in the Northeast, the establishment of a similar program could provide incentives to conserve agricultural habitat in the region in the future.
The Wetlands Reserve Program (WRP), started in 1991, is a voluntary USDA program to help farmers and other landowners take agricultural lands out of production and restore them as wetlands. Eligible lands include wetlands farmed under natural conditions, farmed wetlands, formerly converted cropland, commenced converted wetlands, farmed wetlands pasture, stream corridors, or land substantially altered by flooding. Technical and financial assistance is provided by NRCS. Landowners could receive up to 100 percent of the value of the property and up to 100 percent of the restoration costs. In some cases, farmers may sell a permanent or long term easement to the federal government. In other cases, wetlands may be restored through a simple agreement. Under this program, conservation easements are purchased form landowners to restore, enhance, or create wetland areas. Ownership, control of access, and some compatible uses remain with the landowner. Information about restoring wetlands is available form NRCS at the local Soil and Water Conservation District offices.
The Partners for Wildlife Program (PFW) was created by the US Fish and Wildlife Service (USFWS) in 1002 to assist private landowners, including farmers, corporations, and private organizations, with habitat restoration projects. Under this program, the USFWS helps landowners with habitat restoration projects such as reseeding areas in native vegetation and restoring wetlands. For more information, contact:
Partners for Wildlife Coordinator
USFWS Northeast Regional Office
200 Westgate Center Drive
Hadley, MA 01035
The Wildlife Habitat Improvement Program (WHIP) is a new program administered by the NRCS in each state through the 1996 Farm Bill. The purpose of WHIP is to help landowners develop habitat for upland wildlife, wetland wildlife, threatened an endangered species, and fish. In the New England states, grassland restoration has been listed as a priority to improve wildlife habitat through practices such as brush control, mowing, burning, native vegetation planting, and fencing. The NRCS will provide money through a 75 percent cost share. For more information on the WHIP program in your state, contact your local district conservationist at the state NRCS office.
The American Farmland Trust (AFT) is a national organization working to protect productive farmland while encouraging farmers to improve the stewardship of their land by suggesting conservation options available to farm owners. The AFT helps officials at the local, state, and national levels to create public policies that protect farmland and offer voluntary incentives for improving land stewardship. One such method is a conservation easement, a restriction that landowners can voluntarily place on their property to protect natural resources such as topsoil, water quality, and wildlife habitat, or to protect the land for farming into the future. An agricultural conservation easement is voluntary, legally recorded agreement between the landowner and the AFT (or another qualified conservation organization) that prohibits or limits development that would damage the agricultural value or productivity of the farmland. Under this easement, a landowner my be eligible for tax benefits. For more information about agricultural conservation easements or other programs, contact:
AFT Northeast Office
Herrick Mill, 1 Short Street
Northampton, MA 01060
MASSACHUSETTS AUDUBON SOCIETY AND AGRICULTURE
Massachusetts Audubon has consistently supported agriculture as a land use that is necessary for the production of food for human consumption. The society recognizes that farms provide habitat for wildlife, and has supported federal and state laws and programs aimed at maintaining land in agricultural production and avoiding conversion of farmland to development. Massachusetts Audubon acknowledges the valid role of agriculture within the state's economy, its historic place a land use consistent with maintaining rural character, and its value in maintaining open space. This booklet is aimed at providing recommendations for managing open space for wildlife when appropriate, and is not intended to influence changes in agricultural production.
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