HomeMy WebLinkAbout850671.tiff 2103 - 9th Avenue
Greeley, CO 80631
December 30 , 1984
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TO: Colorado Department of Health
Weld County Commissioners ,--- �3 ,� J
Colorado Landfill , Inc.
FROM: Dr. M. N. Stamper , Ornithologist R'E .
RE : Bird Populations In The Vicinity Of The Erie (Columbine)
Landfill
l i.i_Ci of report is one in a continuing sciies of letters to the
above named parties updating the bird study at Erie Landfill , recently
renamed Columbine Landfill.
As in previous reports, scavenger birds have not been a major problem
at the landfill . There were periods when gulls appeared at the land-
fill, but the practice of prompt coverage of waste has discouraged them
from remaining to feed. On Monday, December 11, 1984 , one hundred
or more gulls were sighted wheeling over the landfill . Several were
landing only to be flushed by the bulldozers which were covering the
trash as it arrived. This was the only occasion on which I saw gulls
since the last report, but the operators reported that gulls appeared
from time to time but did not remain to feed.
This is not to say that scavenger birds and especially gulls might not
become regular feeders at the landfill if trash was not promptly
covered. Gulls are indeed regular visitors at most landfills with
less efficient covering and packing procedures .
The fact that there are no large bodies of water near the Columbine
Landfill on which the gulls may congregate to rest and spend the night
is a positive factor in discouraging gulls from remaining in the
landfill area. A negative factor , which has tended to hold the gulls
a:ea and keep tf:en fi oal tiigrating to their southern wintering
grounds , is the very mild fall and winter of 1984 . But it is also
true that gulls are a hardy group of birds and some will remain as
long as there is food and open water available. The open water need
not be extensive to retain gulls but food is an absolute necessity
and its absence will insure that gulls move on. It is my opinion that
with proper coverage of landfills and other sources of waste materials
the Winter population of gulls in Colorado could be effectively
eliminated.
650671
J
Colorado Department of Health
Weld County Commissioners
Colorado Landfill , Inc.
December 30 , 1984
Page Two
Population Trends
Native bird populations at the three observation posts of the area
have tended to decline during the three years of observation. The
added activity at all three observation posts has reduced habitat and
discouraged nesting activity. In the case of the landfill area, the
intense use of the fill and the clamor associated with coverage and
maintenance has all but eliminated nesting and drastically reduced the
habitat for ground nesting birds . On some trips , I would see no birds
of any kind in the landfill area.
At the control observation area two miles due north of the landfill ,
population decreases are due to the intensive use of the land for
wheat farming. Fence row habitats have all but disappeared as close
plowing has enlarged the wheat fields on both sides of the fence .
County road number 10 has been doubled in width and drastically reduced
any previous nesting habitat and feeding grounds along the right of
way. So long as these practices prevail , native bird populations will
continue to decrease.
The area of the airport has also seen a decline in native bird popula-
tions . One factor here is the addition of hangars near the Coal Creek
habitat area and the use of ultra-light planes based in the hangars .
Construction of the facilities resulted in fill dirt being dumped over
much of the Coal Creek habitat and the low-flying ultra-light planes
disturbed the nesting adults and fledging young. These and other
factors have resulted in reducing the native bird population by one-
half . By contrast, the population of pigeons has remained relatively
constant. It is also true that starlings have increased around the
hangars and the airport restaurant during the study period.
Conclusions
By way of conclusions , there has been a general decline in the native
birds due to man' s activities during the period of this study and
that scavenger birds have been held in check at the landfill by
effective coverage of the trash, while domestic birds , such as the
pigeons and starlings , have held constant or increased in numbers .
Adenda
It is my desire that this letter conclude the series of reports and
that I be released from the agreement to study the population of birds
in the landfill area. This suggestion is prompted by personal reasons
Colorado Department of Health
Weld County Commissioners
Colorado Landfill , Inc.
December 30 , 1984
Page Three
which will take me out of the State for extended periods of time and
further by the fact that continued study would contribute little value
to the factual content or practical value of the study. It is my hope
that all concerned will agree with this suggestion and that the study
has indeed contributed to the knowledge and practices of the important
problem of waste control.
Respectfully submitted,
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Ma a 1 Stamper 0
Ornithol ist
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