Considering Bird-Strikes at OPPD Building in Downtown Omaha

Bird strikes occur consistently and regularly at a multitude of buildings located in downtown Omaha, yet only in 2009 and 2008 has the extent of these occurrences been realized by surveys.

Most officials responsible for managing these buildings may not realize the danger of their structure, but in a few instances the management has realized what is occurring and taken steps to address the hazardous conditions.

At the Energy Plaza, the corporate headquarters of the Omaha Public Power District, measures to reduce the extent of bird strikes were undertaken once they were informed of the situation by federal officials.

Since any steps to make a building bird-safe include economics, an evaluation can convey how the instances of bird strikes at the OPPD Energy Plaza have been different following this expenditure.

Bird Strikes Casualties

Through the end of October 2009, there were 27 known instances of birds being found around the Energy Plaza. Thirteen occurred in 2008, and the remainder in 2009, according to ongoing efforts to document bird-strikes at the buildings in downtown Omaha.

This is a summary of known instances:

Bird Species	Jul 2008	Sep 2008	Oct 2008	May 2009	Jun 2009	Jul 2009	Aug 2009	Sep 2009	Oct 2009
Sora	-	-	-	-	-	-	1	-	-
Mourning Dove	-	-	-	-	-	-	1	-	-
Northern Flicker	1	-	-	-	-	-	-	-	-
House Wren	-	-	-	-	-	-	-	1	-
Marsh Wren	-	2	-	-	-	-	-	-	-
European Starling	-	-	-	-	-	1	-	-	-
Nashville Warbler	-	-	1	-	-	-	-	-	-
Yellow Warbler	-	1	-	-	-	-	-	-	-
Ovenbird	-	-	-	-	-	1	-	-	-
Mourning Warbler	-	1	-	-	-	-	-	-	-
Common Yellowthroat	-	-	-	1	-	-	-	-	-
Wilson's Warbler	-	1	-	-	-	-	-	-	-
Chipping Sparrow	-	-	-	-	-	-	-	-	1
Clay-colored Sparrow	-	1	-	-	-	-	-	-	-
Grasshopper Sparrow	-	-	-	-	-	-	-	-	1
White-throated Sparrow	-	-	-	-	-	-	-	-	1
Harris's Sparrow	-	-	-	-	-	-	-	-	1
Dark-eyed Junco	-	-	-	-	-	-	-	-	2
Common Grackle	3	2	-	-	1	1	-	-	-

In the spring of 2009, OPPD spent more than $8,000 to install CollidEscape on windows where there were known occurrences of bird strikes.

An obvious consideration is if the money spent has made any difference in the number of bird strikes. Only the details can reveal these details.

There have been 19 species found around Energy Plaza. Two of these can be readily excluded any further consideration. The European Starling - an introduced species - can be excluded since it is not protected by the Migratory Bird Treaty Act. The Sora found on the south end of the east side of the building, was found nowhere near a window, so this instance can be attributed to some other unknown cause.

Obviously shown in the records - comparing times before and after installation of the window films - is the difference in the number of strikes involving warblers, which are mostly lower-canopy foragers, thus occurring in trees. There were four in 2008, with half as many in 2009, with only the Ovenbird found in the vicinity of where the windows had been covered.

Common Grackles have consistently been noted as casualties. The 2009 instances were juveniles, which had struck a hazard above the ground level windows. The deaths are lamentable, but it is questionable whether thousands of dollars should be spent to address a situation hazardous for a very common species in downtown Omaha, especially since other locales are notably deadlier.

The most recent bird strikes have been on the east side of the building, and were mostly sparrows and the junco, which are ground-feeding species according to an anlysis of guild information. This indicates any local landscaping was not an influence, since trees would not make a difference as to where these birds would occur. Among the tally were the Grasshopper Sparrow, Chipping Sparrow, Dark-eyed Junco and Harris's Sparrow.

The strikes do indicate another hazard, associated with the glass wall and interior lighting. As these bird were moving along during their migration, and stuck in the streets of the urban Omaha setting, they were confused by the situation at the Energy Plaza, and struck the glass, to their everlasting demise.

This situation can be improved by turning off interior lights in this portion of the building during the migratory period for birds in the valley of the Missouri River.

OPPD's effort provide an important perspective that helps to understand instances of bird strikes in Omaha. It seems readily apparent that their efforts have made a difference in reducing bird strikes at the Energy Plaza.

Further evaluations - at this building and elsewhere - will be be essential in making the buildings of downtown Omaha places which are bird-friendly.