14 May 2009

Considering Biogeography of Avifauna in the Central Niobrara Valley

Niobrara Valley at Fred Thomas WMA. May 15, 2009.

The unique distinction of the central Niobrara valley as a corridor with a changing range of occurrence for a number of different species of birds is readily apparent in the occurrence shown by historic records. This particular facet of the valley biology, was indicated in my research paper on the birds of the Niobrara River Valley (Transactions of the Nebraska Academy of Sciences, 1989).

Since that analysis was done two decades ago, there has been a limited amount of additional field work that conveys specific details of the current status of particular species. In addition to personal surveys, and online reports, there are many records collected by Dave Heidt at atlas blocks for the Nebraska Breeding Bird Atlas II. It is his up-to-date, and most recent observations which have made this analysis possible.

This essay considers only those records available since 1989. The area considered is Rock, Keya Paha, Brown and Cherry counties which comprise the central Niobrara River Valley. Records are available for many particular geographic locales closely associated with the river valley environs (i.e., within a township of the river channel). Overall there are more than 5100 records available for this period of time to consider for an analysis of avifaunal occurrence and distribution.

The sites listed for each species are given in an east to west manner. The site names given are based on specific geographic place names, including attributions for unnamed places based on the first to name standard.

Prairie Falcon - eastward limit during breeding season

Most recently noted during the breeding season eastward in the valley at the south Irwin Road in June 2006 where fledged young were observed. Previously noted at the Bear Creek confluence in May 1989, also in Cherry County.

Virginia Rail - northern extreme of range during winter season

Winter occurrence in wetlands along the river channel only noted very recently. Thirteen records for late-October to mid-February from Niobrara Tract, McKelvie Forest, Circle J Reserve south of Nenzel, Mogle Falls and Jim Gray Place along the Niobrara River south of Merriman.

American Woodcock - westward limit during breeding season

One June 22, 2006, one was flushed once, then again, near the Buffalo Bridge, at Fort Niobrara NWR. The only other regional record was in March 2007 at Goose Lake WMA, in southern Holt county, when it was noted by Loren Blake.

Common Poorwill - westward limit during breeding season

Thomas Creek WMA: 06/06/2007
Springview Bridge: 07/02/2006
Devils Gulch: 05/14/2006
Meadville Bridge: 07/09/2006
Norden Bridge: 06/23/2007
Wazi Oshki: 05/15/2009
Fort Niobrara NWR: 07/16/2006

Among the Niobrara River and its tributary valleys, the region has different species of nightjars, especially in the lower, or eastern Niobrara River Valley, where three species can be experienced at places such as Bohemia Prairie WMA in Knox county. The biological significance of this has not been studied to perhaps consider habitat partitioning, range overlap or other biotic considerations worthy of focused studies.

Whip-poor-will - westward limit during breeding season

Bone Creek Confluence: 06/17/2008
Thomas Creek WMA: 06/17/2008 and 07/13/2008
Springview Bridge: 06/17/2008
Meadville Bridge: 07/15/2006
Norden Bridge: 06/23/2007

These records are all courtesy of Dave Heidt.

Red-bellied Woodpecker - western extension in range

Records from Turpin Lake, Niobrara River; Focken Marsh east of Mariaville, named in recognition of the property owners; Carns Bridge*; Bone Creek Confluence* which is within a block delineated for the breeding bird atlas project; Fred Thomas WMA; Keller SRA*; Meadville Bridge*; Kewanee Creek; and, Circle J Reserve.

The places marked with an asterisk are from the breeding season.

Western Wood Pewee - eastern limit during breeding season

Has occurred during the breeding season at Fort Niobrara NWR including the Bur Oak Nature Area, Government Canyon, the Valentine Fish Hatchery, Valentine City Park, Highway 97 at Niobrara River, Anderson Bridge WMA, and Circle J Reserve.

There are no known records from eastward of the Fort Niobrara NWR vicinity.

Eastern Wood Pewee - western limit during breeding season

From Mariaville westward to Anderson Bridge WMA as indicated by 30 records. All of the records, except one, are from Valentine eastward. The western record for May 30, 2007 is from a Nebraska Game and Parks Commission birding day visit to the wildlife area at Anderson Bridge.

There is no current knowledge of the hybrid zone for the wood-pewees along the Niobrara.

Yellow-throated Vireo - western limit during breeding season

One observed May 30, 2005 at the Bur Oak Nature Area of Fort Niobrara NWR, when birder Sylvia Gallagher was visiting, and included this species in the trip journal, published on the web. The only other pertinent record for this species was on June 17, 1964 along the Niobrara River in Brown County, as documented by Lester L. Short, Jr.

Rock Wren - eastern extension during the breeding season

On the rocky bluffs north of Mogle Falls on June 23, 2006. Historically noted on May 3, 1982 at the Niobrara Valley Preserve, indicating that the species' range is probably more expansive than the single modern record indicates. Also on September 16, 1988 at Fort Niobrara NWR.

Marsh Wren - northern extreme of range during winter season; also a breeding season resident

Winter occurrence in wetlands in the river valley documented only recent observations. Observed at Anderson Bridge WMA, the Niobrara Tract of McKelvie Forest, Circle J Reserve, Mogle Falls, and Jim Gray Place during December to February, in 2004-2006.

Although these records are all from Cherry county, this species may occur in similar habitats eastward in the river valley. There is an obvious dearth of winter observations for the modern period, with any records for this season nonexistent in the historic records.

Winter Wren - northern extreme of range during winter season

Winter occurrence at spring-branch canyons along the river only noted since 2004. From the end of October to mid-February at Bobcat WMA, Conservancy Swamp on the Niobrara Valley Preserve, Krzyzanowski Tract south of Smith Falls State Park, Sears Falls on the Fort Niobrara NWR, Borman Bridge WMA, Anderson Bridge WMA, Buckhorn Springs at the northern edge of McKelvie Forest, Circle J Reserve and along the river at Mogle Falls.

During the breeding season on May 23 and June 13, 2000 at Tyler Creek and Falls, at Fort Niobrara NWR.

This species is likely to occur at numerous other suitable spring-branch canyons which have flowing water throughout the winter season, despite any extreme cold weather conditions.

Wood Thrush - western limit during breeding season

A single record for May 23, 2006 in the vicinity of Valentine.

Black-and-white Warbler - western extension of range during breeding season

Prevalent along the central Niobrara valley, with more than 30 records of occurrence from the Mariaville Bridge vicinity to the valley south of Nenzel.

American Redstart - western extension of range during breeding season

There are 53 records of occurrence for this species from south of Irwin, in western Cherry County to Mariaville. The latest seasonal occurrence is mid-July.

Ovenbird - western extension of range during breeding season

About 82 records from western Cherry County - south of Irwin - to the Mariaville area in Rock county. This is a regular and prevalent breeder in the Niobrara Valley. The western limit to its occurrence is not known.

Scarlet Tanager - western extension of range during breeding season

These locales are where this species has been seen, most recently:

Creeper Creek: 06/19/2006
Carns Bridge: 07/01/2007
Thomas Creek WMA: 06/16/2007
Fred Thomas WMA: 06/21/2006
Meadville Bridge: 07/15/2006 and 06/16/2007
Valentine Area: 05/23/2006

Its range is indicated at least as far westward as near Valentine.

Western Tanager - eastern limit of range during breeding season

There are no known modern records of this species for the central Niobrara River Valley. Last noted by an 1955 notation by Youngworth in his paper on birds of the Quicourt valley, particularly in the region of the Niobrara Game Preserve.

Rose-breasted Grosbeak - western extension of range during breeding season

Noted at:

Creeper Creek: 06/19/2006
Keller SRA: 05/14/2008
Meadville Bridge: 06/23/2008
Valentine City Park: 06/06/2003
Anderson Bridge WMA: 05/30/2007
Circle J Reserve: 06/10/2006

The breeding season distribution of this species extends at least into central Cherry County, with its true western limit not known.

Northern Cardinal - western extent of range

In 1932, Youngworth noted how this species was present at the Niobrara Game Preserve, now called Fort Niobrara NWR. Five decades later, it had continued to expand its range westward, and was noted at Anderson Bridge WMA in the latter 1980s. In June 2006, this red-bird was present during the breeding season along the river, south of Irwin, an indication of it moving westward due to an increase in woody habitat along the river valley. A record in western Cherry county is a blatant indication of an obvious change in range, yet its current western extent is not known to any observers.


Any understanding of bird occurrence and range of birds for the central Niobrara River valley is based upon a drastically limited extent of records. Many of the observations were made at a limited number of places readily accessible to tourists or volunteers for an atlas project, limiting a comprehensive view of distribution.

There is also a seasonal skew to information, with most of the details having been gathered during the breeding season.

The knowledge of current bird distribution along the central Niobrara Valley is almost entirely based upon volunteer efforts. Exceptions are a recent study of habitat considerations done by University of Nebraska-Lincoln students at the Niobrara Valley Preserve. National Park Service staff have also been monitoring the occurrence of the Piping Plover and Least Tern during its nesting period.

Information of particular detail is lacking - much of it based on historic articles - despite the apparent importance of the Niobrara River valley in any study of the variable biogeography of birds. Any flux in bird distribution that may be happening due to changing climate and habitat conditions, would occur at the edge of a species range, features historically indicated along the Niobrara valley.

There is an obvious need for more extensive surveys that can indicate changing conditions for birds in the Niobrara Valley. There are no studies being funded for such an effort, though there are several potential sources which could provide money. This includes obvious contributions by the various agencies involved with the management of the scenic river.

Understanding the birds of the Niobrara Valley should not be left to volunteer efforts, but should be given specific and ongoing research attention, with ample funding provided for obvious, essential research endeavors. Funds should also be allocated to create a record base of sightings which can provide an archive of details for comparative purposes.

Funding of biotic investigations is required to understanding the unique and vital aspects of fauna along the Niobrara River valley. With the obvious instances of dramatic variation for the range of many bird species, an understanding of the valley's bird biogeography should be based on active research in the field, not the office.

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