Malheur National Wildlife Refuge
Pacific Region
 

Management

Malheur was established in 1908 to provide habitat for migratory and resident birds. In 1966 the National Wildlife Refuge Administration Act determined that activities on National Wildlife Refuges must be compatible with the purpose for which the refuge was established. Compatibility determinations have been completed for all components of the refuge's habitat management program. Major components of this program include haying and grazing, prescribed burning, periodic drying of ponds and wetlands, grain farming, riparian restoration projects, removal of encroaching juniper and the eradication of noxious weeds.


Haying and Grazing

Migratory and resident birds utilize upland, meadow, marsh and riparian habitats for feeding, nesting, breeding and brooding. Of these four habitat types, meadows are the only areas where grazing and haying are prescribed. Grazing and haying are considered habitat management tools in meadows because, when properly regulated, they actually facilitate bird use. To be compatible managers must regulate the timing, method, duration and intensity of treatments.

Timing is regulated to minimize impacts to birds and other wildlife. Haying occurs no earlier than mid-August so that nesting or young birds are not disturbed. Grazing occurs during the fall and winter, so that the breeding season is not interrupted.

Methods are selected depending upon the circumstances involved - is there standing water? what are the previous uses in the field? are there numerous weeds? Two methods are used - Hay Only or Rake-Bunch Grazing. In Hay Only fields the meadow grasses are cut, baled and then removed from the refuge to feed livestock. In Rake-Bunch Grazing fields the meadow grasses are mowed and raked into bunches. Livestock are introduced to the field to graze either the rake-bunched hay or the remaining unmowed grasses. Duration and intensity are carefully calculated to prevent overgrazing or deterioration of native plants.

Prescribed grazing and haying of meadows provide feeding benefits to cranes, ducks and geese. The removal of vegetation allows solar heat to warm up the soil early in the spring. This early thawing of the ground increases the activity of protein-rich invertebrates, such as earthworms. It also stimulates earlier growth of new vegetation, which serves as an important food source. The invertebrates and new vegetation provide high protein sources needed by birds for egg laying and nesting, and as fuel for birds who continue their migration flights to the arctic and sub arctic.

Pond Management

Ponds and wetlands on the refuge are periodically dried up to maintain their productivity. The ponds and wetlands must be exposed to the atmosphere to allow bacteria, fungi and a variety of invertebrates to breakdown accumulated organic matter and release stored nutrients. Many wetlands also become overrun with dense stands of cattails, bulrush and sometimes common carp. When this occurs wetland productivity and wildlife diversity is greatly reduced. Fire and mechanical means (disking and harrowing) are also used to set back succession, release nutrients and expose sediments and dormant seeds to the atmosphere.

Many high quality aquatic and semi-aquatic plants (smartweeds, beggars tick and red goosefoot) have highly resistant seeds. These seeds lay dormant in the sediments of ponds for years. They only germinate under specific conditions which expose them to the right combinations of moisture, air and sunlight during the growing season. These conditions may be promoted in wetlands through slow drawdowns of ponds and wetlands - essentially induced droughts - to encourage the reinvigoration of plant communities. After these plants germinate and become established, ponds and wetlands are slowly refilled throughout the summer. This management strategy is referred to as "moist soil management". Seeds of smartweeds and other species are highly sought after by many bird species, especially during fall migration.

Small grains (rye, wheat, barley and millet) are also planted in pond bottoms. Pond bottoms have highly organic soils, are very fertile and retail moisture long into the summer. They are also easily irrigated to encourage growth. In the early fall these farmed pond bottoms are slowly flooded to provide food for fall migrating sandhill cranes, ducks, geese and songbirds. Under some circumstances wetlands are simultaneously managed for both moist soil plants and grain. These ponds produce diverse food resources and support diverse bird populations.

When a moist soil unit or grain field is flooded in the summer or early fall, subsequent spring migrants, summer broods and molting adults also benefit. In the short period after the initiation of flooding a wide variety of aquatic invertebrates colonize the newly flooded habitat. Some (midge larvae) colonize the sediments, while others (snails) use the flooded vegetation as substrate for feeding. Bacteria, fungi and algae become established on the flooded vegetation, which are in turn fed upon by a variety of aquatic invertebrates. These aquatic invertebrates are an extremely important source of protein for waterfowl and shorebirds who breed locally or are on their way to breeding grounds in the arctic. Female waterfowl and shorebirds may delay or forego nesting if they do not gain enough weight and consume enough high protein foods prior to nesting. Fast growing ducklings, crane colts, and shorebird chicks need food high in protein and lots of it so they can be ready for fall migration. After breeding adult ducks completely molt their flight and body feathers over a 2-4 week period. Many ducks continue their molting during the fall migration. Molting waterfowl consume a diet high in protein. Aquatic invertebrates are the major source of that protein.

Prescribed Fire

Prescribed fire is the safe use of fire under specific condition to achieve land management objects. On Malheur Refuge prescribed fire is used to promote the growth of wetland plants, to enhance the long term viability of wetlands, to remove decadent vegetation from meadows and uplands, and to mimic natural cycles of fire while reducing fuel loads. More information about the use of prescribed fire on refuges can be found at the Service's Fire Management site.

Weed Eradication

Non-native, noxious weeds have a detrimental effect on native plant communities by reducing native plant diversity and viability, which in turn impacts wildlife habitat. The refuge, in coordination with refuge haying and grazing permittees, has been treating stands of perennial pepperweed and Canada thistle with herbicides to reduce infestations of these non-native, noxious plants. The refuge is also using herbicides to treat encroachments of Russian olive trees and small occurrences of other non-native plants.

Comprehensive Conservation Plan

The refuge has begun preparation and planning of it's Comprehensive Conservation Plan (CCP). The CCP will guide future managment decisions when it is completed. To learn more about the CCP process visit our planning page.

 

 

 

 

 

 
Last updated: August 23, 2011