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Idaho Birding Trail LogoMale Sage GrouseMountain Bluebird
Southeast Region

Mackay Reservoir and Chilly Slough

Nearest Town: Mackay
Site Size: Mackay-1300 acres, Chilly- 5840 acres

Highlights: Raptors, Shorebirds, Songbirds, Upland Birds, Waterbirds, Waterfowl

Access: Year-round. Access free of charge.

Site Location

Directions: MACKAY RESERVOIR: from Mackay, US 93 NW 5 mi to Mackay Reservoir; access places along E shore at mp 112.9, 113.6, and 114.5; the NW and SE ends of the reservoir (by the inlet and outlet) are private land; rest of the shoreline is public (BLM). CHILLY SLOUGH: continue NW on US 93; at mp 126, L into graveled pull-out.

Description: Exposed mudflats at the reservoir in spring and fall attract numerous shorebirds and waterfowl, including Cinnamon and Green-winged Teal, Northern Shoveler, Northern Pintail, and scaup. From spring through fall, Chilly Slough is rich with birds, including Willet, Sandhill Crane, Sora, Marsh Wren, Savannah Sparrow, Red-tailed Hawk, Golden Eagle, and Northern Harrier.

More Information:
BLM (208) 879-6200
City of Mackay (208) 588-2693

Lesser Scaup
Photo Copyright Camden Hackworth
Marsh Wren
Photo Copyright Michael Woodruff

General Services:
ParkingRestroomsNo PhoneNo BoardwalkCampgroundPicnic AreaNo Observation AreaNo Visitor CenterNo Interpretive Material AvailableBoat RampNo ConcessionsHiking TrailsHuntingFishingWater SportsOHV/ATVs AllowedHorseback Riding

Handicapped Services:
No ParkingNo RestroomsNo PhoneNo BoardwalkNo CampgroundNo Picnic AreaNo Observation AreaNo Visitor CenterNo Interpretive MaterialsNo Boat RampNo ConcessionsNo Hiking Trails
What do these icons mean?

marshes/lakes/ponds Graph illustrating 80% 80%
other Graph illustrating 10% 10%
sage/shrub Graph illustrating 10% 10%

Best Observation Times
Bird Species Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec AM/PM
Raptors N N N Y Y Y Y Y Y N N N ALL
Shorebirds N N N Y Y N N Y Y Y N N ALL
Songbirds N N N N Y Y Y Y N N N N AM
Upland Birds N N N N N N N N N N N N
Waterbirds N N N N Y Y Y Y N N N N ALL
Waterfowl N N Y Y Y N N N Y Y Y N ALL
Target Species for this Site

Select a species from the list to view other sites on the Idaho Birding Trail Sites this species may be observed.

    Bittern, Herons and IbisesBlackbirds and alliesCranesFinches and alliesGeese, Swans and DucksHawks and EaglesRails and CootsShorebirdsSparrows and alliesSwallowsThrashersWood WarblersWoodpeckersWrens and Dipper


    R - Resident 1 - Abundant, easily found s - Statewide
    M - Migrant 2 - Common, but sometimes difficult to find e - Southeast
    W - Winter 3 - Uncommon or local w - Southwest
    S - Summer 4 - Rare or very local c - Central
    5 - Casual, 3-10 accepted records p - Panhandle (North)
    6 - Accidental, 1-2 accepted records
    7 - Experimental
    (B) - Documented breeding evidence(End) - Threatened or Endangered
    (b) - Circumstantial breeding evidence(Int.) - Introduced species

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