Your guide to Hawkeye Wildlife Management Area: Trails to explore and birds to discover

Hawkeye Wildlife Management Area is one of the premier birding spots in Iowa.

More than 300 bird species have been recorded within the boundaries of the area. This is largely due to its size and wide variety of habitat. At just under 14,000 acres, habitats include flood plain, large stands of timber, grassland, marshland and uplands.

The DNR is restoring prairie savanna and sandy ridge habitat in select locations. The WMA is divided into east and west. For bird-watching in the WMA, the main roads to know are Amana Road NW (for access north of the Iowa River) and Swan Lake Road NW (for access south of the Iowa River).

Geology and archaeology

There are some neat geological features at Hawkeye WMA.

At the height of the last glacial maximum, around 20,000 years ago, prevailing northwest winds shed off an ice sheet covering what is now referred to as the Des Moines Lobe. These winds, along with sand deposited from a 'paleo-Iowa River,' helped form active sand dunes in areas around and nearby the WMA. Both longitudinal (linear-shaped) and parabolic dune (crescent-shaped) forms are stabilized under natural vegetation and agricultural fields.

Half Moon Avenue, a rural access road into the WMA, owes its namesake to nearby parabolic dunes. Some of these dunes have been eroded over time by tributaries of the current Iowa River, forming sandy terraces. Although many of these terraces have been eroded away by the waxing and waning of the Iowa River, the few high places that still escape floodwaters were important settlement locations for Native Americans as well as mid- to late 19th Century homesteaders.

Native Americans likely caught fish in rock-built traps on the Iowa River, as is evident in an archaeological site just west of the WMA near the Amanas.

Accessing Hawkeye WMA

South of Iowa River — Take I-380 to the Penn St NW exit for North Liberty and head west on F28. The first three gravel roads turning north (James Ave NW, Half Moon Ave NW, and Greencastle Ave NW) all feed into the southern areas of the WMA. Take any of these gravels to Swan Lake Rd NW. Both parking lots for the following trails are located along this road.

Mallard and Gadwall Ponds Trail

Target species: Henslow's sparrow, field sparrow, blue grosbeak, eastern meadowlark, bell's vireo.

Parking location: The parking lot is located along Swan Lake Rd NW, west of the Greencastle Ave NW/Swan Lake Rd NW intersection. Once you pass under large utility wires you are almost there.

Take the blocked off access road just south of the parking lot and hike south. The access road trail is fairly level and dry. At the very end there is a creek crossing which requires some type of waterproof mud boot. However, most of the area does not require this type of footwear. Habitats include mostly grassland, hedgerows and marshland. Look for henslow's and field sparrows and eastern meadowlark in the grassland.

Listen for bell's vireo singing a 'fast and angry-like' song from the hedgerow habitat. Blue grosbeak are often found in the grassland and hedgerow habitat. Males will sit atop perches singing their pleasant, warbling song. This also is a highly recommended birding trail in the spring and fall.

Sand Point and Swan Lake Trails

Targets: Wood thrush, gray catbird, wood duck, green heron, horned lark, lark sparrow, yellow-billed cuckoo, barred owl, great horned owl.

Parking location: This parking lot is located on the northeast corner of Swan Lake along Swan Lake Rd NW. It is west of the James Ave NW/Swan Lake Rd intersection.

Take the blocked off access road at the northwest corner of the parking lot. These access roads trails are fairly level and dry. Head north along the road through timber habitat. Listen for wood thrush to the east in the timber. You may also hear field species, such as field sparrow, in adjacent private land to the west. Also look for gray catbird, woodpeckers and barred and great horned owls. After 5 to 10 minutes of hiking there is a pond on the east side of the road at an older, dilapidated parking lot. Explore this pond for wood duck and green heron, but take a slow and quiet approach as these species tend to flush when they see or hear people.

Another 50 yards north on the trail the timber ends. At this point there are two options:

— Head north toward Sand Point following the road along usually fallow or planted agricultural fields. Look on the road for horned lark that breed in nearby fields. While summer is not the best time to explore Sand Point, early to late spring is a great time to see American white pelican, all types of waterfowl, wading birds such as herons and many types of shorebirds. This area is closed to the public as a reserve during portions of the fall.

— Head east along another visible access road. This goes roughly a mile east toward James Ave NW. There is a variety of habitat along this road, including timber edge, shrub land, grassland and marshland. Keep an eye out for nesting great horned owls along the timber edge habitat to the south. Field, song and lark sparrows can be found along the northern side of the trail. The more common yellow-billed cuckoo and less common black-billed cuckoo also may be seen. Keep an eye out for American redstart in the woods and common yellowthroat in the grassy to shrubby areas.

Brandon Caswell has undergraduate degrees in biology, anthropology and geology. His graduate degree centered on dating continental collisions within the Precambrian Canada Shield. Bird-watching and nature photography are among his favorite hobbies. Email brandon.caswell83@gmail.com with birding-related questions.