Fourteen artificial nests were monitored, with four in a nature preserve and ten in residential yards. Nests contained quail and clay eggs and were monitored by game cameras. In the nature preserve, 50% of nests were predated, while 60% of nests in yards were predated. Nest predation in yards was lower within 3.5 miles of downtown. The predator community differed between the sites, with jays preying in the preserve but multiple species like grackles, mice, and squirrels taking eggs in yards.

1. Methods
Fourteen sites were monitored. Four sites were
located at Wild Basin Wilderness Preserve, and
ten sites were located at different residential
yards in Austin, Texas (Figure 1).
One artificial nest was placed at each of the
fourteen sites. Each nest was wired to a tree,
shrub, or vine tangle at approximately 2 meters
high, to mimic nest placement of the Northern
Cardinal (Cardinalis cardinalis). Three eggs were
placed in each nest: two quail eggs and one clay
egg. Game cameras were set adjacent to the
nests to capture 60-second videos of any activity
at the nest. Nests and cameras were set up for
one week. Videos from each nest were watched
in the lab, and all activities at the nest (wildlife
inspecting nest, touching egg, taking egg, etc.)
were logged in a datasheet.
For each site, ArcGIS was used to characterize
the impervious ground cover, tree canopy cover,
distance from downtown, proximity to a
greenspace, distance to nearest major road, and
distance to nearest water source.
Acknowledgments
I would like to thank the National Science
Foundation for funding the summer research. I
would also like to thank Dr. Kopec at St.
Edward’s University and Dr. George Staff at
Austin Community College. Thank you to Dr.
Amy Belaire, whose enthusiasm and guidance
have been greatly appreciated. I would also like
to recognize Jonatan Salinas and Seth Kramer
who worked with Dr. Belaire and me as a team
assisting one another whenever necessary.
Thank you to the Austin residents who allowed
us to study their yards. Thank you to the
Smithsonian Migratory Bird Center for their
advice.
Results
Over 250 videos of wildlife activity were recorded at the 14 artificial nest sites. Nests
were categorized as predated if any eggs were removed during the one-week study
interval. The predation rate of artificial nests at the Wild Basin sites was 50%,
whereas 60% of the nests were predated in the neighborhood sites. There is also a
trend that neighborhood nests that are closer to downtown are less likely to be
predated – only 20% of the nests within 3.5 miles of downtown were predated,
whereas 100% of nests farther from downtown were predated. There was a
significant positive relationship between nest predation activity (using number of
videos as a proxy) and distance from downtown (Spearman’s rho = 0.80, p = 0.006).
Conclusions
Rates of predation between Wild
Basin and neighborhood sites were
relatively similar. However,
neighborhood sites appeared to
have a more diverse community of
wildlife species that visited and
predated on nests.
In neighborhoods, areas closest to
downtown were less likely to be
predated and had reduced predator
activity at the nests.
Studies in urban ecosystems are
important for biodiversity
conservation and understanding
long-term trends associated with
urbanization. They also help urban
residents connect with and learn
about the wildlife in their own
backyards.
B. Danette Shults & Dr. Amy Belaire
Austin Community College @ St. Edward's University
.
Using artificial nests to explore nest predator species and the
rate of predation across an urban landscape
Introduction
Nest predation threatens the survival and
reproductive success of many birds. The egg is
confined to a single space until it hatches and
matures to fledgling. Nest predators may destroy
the egg or even take live chicks to feed on. As
habitats are destroyed and the human population
grows, it is important to study the effects of
urbanization on biodiversity and the factors that
affect species survival and reproductive success.
With this study, we examined urban nest predation
in collaboration with Neighborhood Nestwatch, a
program developed by the Smithsonian Migratory
Bird Center to understand the effects of
urbanization on wildlife.
Great-tailed grackle
Quiscalus mexicanus
Blue Jay
Cyanocitta cristata
Deer Mouse
Peromyscus maniculatus
Opossum
Didelphis virginiana
Squirrel
Sciurus niger
Northern Cardinal
Cardinalis cardinalis
Figure 1. Map of 14 study sites, 10 in residential
neighborhoods and 4 at Wild Basin.
References
Baicich, Paual J. and Colin J.O. Harrison. Nests, Eggs
And Nestlings Of North American Birds. 2005. 2nd ed.
Princeton: Princeton University Press. Print.
Kruger, Laura and Audra Bassett. "Artificial Nest Predation
Investigation". 2016. Presentation.
Ryder, T.B., R.Reitsma, B. Evans, and P. Marra. 2010.
Quantifying avian nest survival along an urbanization
gradient using citizen- and scientist-generated data.
Ecological Applications 20(2):419-426.
The predator communities differed between Wild Basin and neighborhood sites. The
Western scrub-jay (Aphelocoma californica) and Blue Jay (Cyanocitta cristata) were
the only two species observed to predate the artificial nests at the Wild Basin. The
videos captured at neighborhood sites revealed five species of predators, including the
Blue Jay, Great-tailed Grackle (Quiscalus mexicanus), Deer Mouse (Peromyscus
maniculatus), Opossum (Didelphis virginiana), and Squirrel (Sciurus niger).
Indications of predator activity
on clay egg
Example of artificial nest and camera
placement at Wild Basin