01 June 2008

Downtown Omaha Buildings Deadly for Migratory Birds

An injured Nashville Warbler taken from the hazardous sidewalk at the Edward Zorinsky Federal Building to the tree in a landscaped area on the north edge of downtown.

A survey of bird strikes in downtown Omaha recorded 102 instances during the month of May.

Starting early in the month, a casual survey was made around the tall buildings of downtown Omaha, to evaluate where birds might be found to have hit and structure, causing their death. Once a very significant number of carcasses were noted on May 10, 2008, a survey via bicycle was made daily around the downtown sidewalks in the early morning to document instances of bird carcasses, and occasionally injured birds.

During each survey, the building name and the particular location of the bird species - noting only those classified under the Migratory Bird Treaty Act - was recorded, with a picture or two taken of nearly every instance. If a species identification could not be made, the picture was useful to get assistance from other birders in order to determine the particular identification of the species. Each instance entered into a database according to each building, to help with data compilation and analysis.

When an injured bird was found, it was carefully picked up and moved away from the building sidewalk and any pedestrian traffic, and placed in a landscaped area, and in the case of those within the core area of the downtown building district, it was taken to a park area on the north side of downtown.

[Buildings of Downtown Omaha]

Downtown Omaha buildings. View from the northeast.

Most of the bird strikes occurred repeatedly at several prominent buildings with extensive glass areas serving as exterior walls. Those with the greater number of known instances were:

• Qwest Center Omaha - 33, with six strike occurrences denoted on May 26th; all but one of the occurrences on the west side, including one bird which struck the glass-enlosed, elevated walkway to the hotel across the street
• 1200 Landmark Center - 14, mostly on the north side
• Holland Performing Arts Center - 9, about two-thirds occur in the courtyard area, which as the trees get larger, will be a greater hazard
• Union Pacific Center - 9, mostly at the northeast corner of the structure
• Omaha World-Herald Freedom Center - 9, nearly all were along the west side, though one occurred in the recessed courtyard at the southwest corner of the building
• Central Park Plaza - 8, on the north, south and east sides of both towers
• Omaha World-Herald Building - 5, in the southeast corner
• American National Bank - 4, on the south side
[Reflectivity of the west wall at the Qwest Center Omaha]

Reflectivity of the glass wall on the west side of the Qwest Center Omaha.

View of a portion of the west wall at the QWest Center Omaha.

The strikes occur because of the combination of three items, designated as the deadly Ls: 1) the look of the building, each with a prominent glass exterior wall; 2) lights are known to confuse nocturnal migrants, which are most of the species noted; and 3) landscaping where in most instances leafy trees were planted and are growing in relatively close proximity to a reflective wall, so birds landing in the tree and looking to go elsewhere, would fly towards what would appear to be a suitable destination, but would be a false image. The distance away from the tree would be sufficient for a flight speed where the bird would be strike the reflective surface hard enough for the flying bird to become a fatality.

[1200 Landmark Center reflectivity]

North side of the 1200 Landmark Center building.

[Union Pacific Center]

View from the north of the Union Pacific Center. The area being cleared is where the Wallstreet Tower of glass, 330 feet high will be constructed.

A map is indicates the places and dates where the bird strikes occurred, and many of the instances include a photograph of the scene where the carcass was found.

Map of Bird Strikes in Downtown Omaha


View a Larger Map - This option is recommended in order to best view
the text and photographs for the complete list of bird strike records.

There would be additional strikes at some of these buildings during the month, but only those where visible evidence was present were recorded. If a bird fell onto the entry way overhangs at the Qwest, or on the courtyard ledge at the Holland Performing Arts Center, the carcasses would not be visible, and could not be tallied. Other prominent buildings which may have had bird strikes, could not be evaluated for this same reason. There would also likely be additional instances of strike mortality, but restrictions on accessing private property did not allow any evaluation; the Con Agra Campus for example, with its mix of the three deadly Ls. Some carcasses may have also been carried away by cats and/or dogs, or maybe the few other wild animals that occur, such as opposums.

A table illustrates where 35 different species have flown into a building.

Tally of Omaha Buildings Where Birds Strikes Occurred in May
Bird Species 1200 Land. Ctr. 1405 Harn. 17th Harn. All Makes Amer. Nat. Bk. Cent. Park Plaz. Zorin. Fed. Bldg. Fir. Nat. Bk. Fir. Nat. Twr. Holl. Ctr. OWH Bldg. OWH Free. Ctr. Qwest Ctr. Slow- down NE Off. Bldg. UP Cntr. Wood. Park
Sora - - - - - - - - - - - - - - - - 1 - - 4 - - - - - - - - - - - -
Mourning Dove - - - - - - - - - - - - - - - - - - - - - - 1 - - - - - - - - - -
Hairy Woodpecker - - - - - - - - - - - - - - - - - - - - - - 1 - - - - - - - - - -
Olive-sided Flycatcher 1 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Eastern Wood-Pewee 2 - - - - - - - - - - - - - - - - - - - - - - 1 - - - - - - - -
Willow Flycatcher 1 - - - - - - - - - - - - - - - - - - - - - - 2 - - - - - - - -
Flycatcher - - - - - - - - - - - - - - - - - - - - - - 1 - - - - - - - - - -
Least Flycatcher 1 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Eastern Kingbird - - - - - - - - - - - - - - - - - - - - 1 - - - - - - - - - - - -
Warbling Vireo - - - - - - - - - - 1 - - - - - - 1 - - - - - - - - - - - - - -
Red-eyed Vireo - - - - - - - - 1 - - - - - - - - - - - - - - - - - - - - - - - -
Swainson's Thrush 1 - - - - - - - - 1 - - - - - - - - - - - - - - - - - - - - - -
American Robin - - - - - - - - - - 1 - - - - - - - - - - - - 1 - - - - - - - -
Gray Catbird - - - - - - - - - - - - - - - - - - - - - - 1 1 - - - - - - - -
Tennessee Warbler - - - - - - - - - - - - 1 1 - - 1 - - - - 5 - - 1 4 - -
Nashville Warbler - - - - - - - - - - - - 1 - - - - - - - - - - 1 - - - - 1 - -
Yellow Warbler 1 - - - - - - - - - - - - - - - - 1 - - 1 1 - - - - - - - -
Chestnut-sided Warbler - - - - - - - - - - - - - - 1 - - - - - - - - - - - - - - - - - -
Yellow-rumped Warbler - - - - - - - - 1 1 - - - - - - - - - - - - - - - - - - - - - -
Palm Warbler - - - - - - - - - - - - - - - - - - - - - - - - 2 - - - - - - - -
Black-and-white Warbler - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 1 - -
American Redstart - - - - - - - - - - 1 - - - - - - - - - - - - 1 - - - - - - - -
Worm-eating Warbler 1 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Ovenbird 2 - - 1 - - - - - - - - - - - - - - - - 2 1 - - - - 1 - -
Louisiana Waterthrush - - - - - - 1 - - - - - - - - - - - - - - - - - - - - - - - - - -
Mourning Warbler - - - - - - - - - - 1 - - - - - - - - - - - - - - - - - - - - - -
Common Yellowthroat 3 - - - - - - 1 - - - - - - - - 1 - - 2 7 - - - - - - - -
Chipping Sparrow - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 1 - -
Clay-colored Sparrow - - - - - - - - 1 - - - - - - - - - - - - - - 3 - - - - - - - -
Sparrow - - - - - - - - - - - - - - - - - - - - - - - - - - 1 - - - - 1
Lincoln's Sparrow - - 1 - - - - - - - - - - - - - - - - - - - - 1 - - - - - - - -
White-throated Sparrow - - - - - - - - - - - - - - - - - - 2 - - - - 1 - - - - - - - -
Rose-breasted Grosbeak - - - - - - - - - - 2 - - - - - - - - - - - - - - - - - - - - - -
Blue Grosbeak - - - - - - - - - - - - - - - - - - 1 - - - - - - - - - - - - - -
Indigo Bunting - - - - - - - - - - - - - - - - - - 1 - - - - 4 - - - - - - - -
Common Grackle 1 - - - - - - - - - - - - - - - - 1 - - - - - - - - - - - - - -
Baltimore Oriole - - - - - - - - - - - - - - - - - - - - - - - - 1 - - - - 1 - -
Total Number: 14 1 1 1 4 8 2 2 1 9 5 9 33 1 1 9 1

The species with the greatest extent of deadly impacts were the Common Yellowthroat, with 14 instances of known strikes, Tennessee Warbler (13), Ovenbird (7), Indigo Bunting (5), Sora (5), Yellow Warbler (4), Clay-colored Sparrow (4), Eastern Wood-Pewee (3), Nashville Warbler (3), Willow Flycatcher (3), and White-throated Sparrow (3). About half of the total were warblers, with sparrows also well represented.

A number of the birds killed were females struck down during a hazardous trek to the breeding grounds. They will not be able to raise a brood that would have contributed to the population of their species.

The dates when a greater number of strikes were noted were May 29th, with 11 instances, May 10th and 26th, both with ten instances, and May 31st, with 8 instances. Most of the records - 92 - are during the period of May 10-31, giving an average of nearly four strikes per day.

[Reflective view of the First national Bank Tower]

Reflectivity of the west wall of the Omaha World-Herald Freedom Center. The First National Bank Tower and buildings to the north are shown.

{Holland Performing Arts Center courtyard]

Setting of the courtyard area of the Holland Performing Arts Center. Dead birds have been found under the large square area on the right, and to the left. The trees of the Central Park Mall are directly south of this building.

Each of these species are protected by the Migratory Bird Treaty Act. The demise of a bird caused by a building is considered taking under this Act, and the building owner is liable for the death.

[Building strike carcasses from downtown Omaha]

Ten carcasses found on 10 May.

[More building strike carcasses from downtown Omaha]

Carcasses from building strikes in downtown Omaha on 31 May.

The Nebraska office of the U.S. Fish and Wildlife Service has been informed of the results of this survey, and their representative was asked to inform representatives of the building with the largest strikes that each death of a bird is a violation of the MBTA, which may be subject to law enforcement.

[injured female Indigo Bunting]

Injured female Indigo Bunting, Qwest Center on June 2nd, 2008.

"Migratory birds are federally protected under provisions of the Migratory Bird Treaty Act (16 U.S.C. 703-712: Ch. 128 as amended). The MBTA prohibits the intentional and unintentional direct take (e.g., killing, wounding, destruction of active nests) of migratory birds."

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