Southern Flying Squirrels (Glaucomys volans) as Major
Predators of Avian Nest Boxes in Conecuh National Forest,
Alabama
Brett A. DeGregorio, Jinelle H. Sperry, Daniel G. Kovar, and David A. Steen
Southeastern Naturalist, Volume 18, Issue 3 (2019): 476–488
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2019 SOUTHEASTERN NATURALIST 18(3):476–488
Southern Flying Squirrels (Glaucomys volans) as Major
Predators of Avian Nest Boxes in Conecuh National Forest,
Alabama
Brett A. DeGregorio1,2,*, Jinelle H. Sperry1,2, Daniel G. Kovar1, and
David A. Steen3
Abstract - Bird population dynamics are strongly affected by the ability to successfully
reproduce, and nest predation is the primary cause of reproductive failure for most birds.
Efforts to understand nest predation and manage its effects on species of conservation concern
require knowledge of the ecology of associated predator assemblages. Recently, studies
using cameras to record events at nests have illuminated this previously under-studied avian
life stage, but such studies have been largely limited to open-cup nests. Cavity nests may be
depredated by a different suite of predators, and incubating or brooding females occupying
such nests may be more vulnerable to predation relative to open-cup nests. Here, we used
motion-activated, infrared trail cameras to record predators of artificial nest boxes in a Pinus
palustris Mill. (Longleaf Pine) forest in southern Alabama. Although Glaucomys volans
L. (Southern Flying Squirrel) have only rarely been captured on film preying on nests, we
found them to be responsible for the vast majority (84%) of bird-nest depredations at nest
boxes, and these depredations contributed to a surprisingly low overall rate of nest success
(~20%). These results may have implications for the conservation of birds that nest in artificial
cavities in Longleaf Pine forests and highlight the importance of further studies on
predator assemblages and their effects on nesting birds.
Introduction
Predation is the primary cause of nest failure for many birds (Martin 1993, Ricklefs
1969) and contributes strongly to variation in reproductive success. Thus, nest
predation has played an extensive role in the evolution of avian life-history strategy
(Latif et al. 2012, Martin 1988). Despite considerable work on the consequences of
nest predation for birds, a deeper understanding of nest predation has been stalled
by our lack of dependable information on the identity of the predators (Benson et
al. 2010). Because different predators employ varied foraging strategies, identifying
local predators within a system informs our understanding of how birds might
reduce their risk of nest predation. Furthermore, because nest predation can also
limit the viability of bird populations (Robinson and Wilcove 1994), management
and conservation plans to reduce predation will benefit from knowing which predator
species are most likely to influence avian populations.
1Engineer Research and Development Center. 2902 Newmark Drive Champaign, IL
61822. 2Department of Natural Resources and Environmental Science. University of Illinois
at Urbana – Champaign. 1102 S. Goodwin Avenue, Urbana, IL 29801. 3Georgia Sea
Turtle Center, Jekyll Island Authority, Jekyll Island, GA 31527. *Corresponding author -
badegregorio@gmail.com.
Manuscript Editor: Andrew Edelman
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The increased adoption of miniaturized remote cameras for identifying predators
at nests has vastly improved our understanding of avian ecology and nest predator
identity (Cox et al. 2012a). Armed with the identity of nest predators within a system,
biologists are better able to understand the interactions between nest predators
and breeding birds. For instance, Pantherophis obsoletus Say (Western Ratsnake)
often use forest edges (Blouin-Demers and Weatherhead 2002), which results in
increased nest predation by snakes near edges (Cox et al. 2012b, DeGregorio et al.
2014a). Similarly, nest camera studies have provided novel insights into how proximity
to forest edges and other landscape features such as powerline right-of-ways
can make bird nests more vulnerable to avian predators and brood parasites (Cox
et al. 2012b, DeGregorio et al. 2014b, Rodewald and Kearns 2011). Although the
number of nest studies employing video cameras has steadily increased, a recent
review of research using nest cameras across North America found that studies on
cavity-nesting birds are particularly under-represented in the literature (DeGregorio
et al. 2016). Here, we address this gap using motion-activated trail cameras to
investigate the identity and behavior of predators at artificial nest boxes in Pinus
palustris Mill. (Longleaf Pine) forests of Alabama.
One potential predator of cavity-nesting birds in the southeastern United States
is Glaucomys volans L. (Southern Flying Squirrel, hereafter Flying Squirrel), a
small (60–80 g) arboreal nocturnal sciurid found throughout much of the central
and eastern United States. The species nests, roosts, and stores food in tree cavities,
a habitat that can bring Flying Squirrels into conflict with birds such as the endangered
Leuconotopicus borealis Viellot (Red-cockaded Woodpecker) as well as the
biologists tasked with helping them to recover. Flying Squirrels are often cited as
potential predators of Red-cockaded Woodpecker nests (Laves 1996, Loeb 1993) or
competitors for their cavities (Rudolph et al. 1990), and some management plans,
particularly for small recovery populations, call for the control of squirrels near
woodpecker clusters (Gaines et al. 1995).
Our specific objectives here were to use nest cameras to (1) document predator
identity at avian nest boxes, and (2) quantify the relative importance of predators
within the assemblage. After Flying Squirrels were revealed to be the major
nest predator in this system, we added a third objective: (3) explore the factors
that influenced the vulnerability of nest boxes to Flying Squirrels. Understanding
the timing of predation by Flying Squirrels, the stage of nesting that is most
vulnerable to these predators, and the outcomes of predation events can inform
future research and conservation efforts related to birds that may be impacted
by these little-known nest predators. We chose to monitor predation at artificial
nest boxes because they allowed us to generate large sample sizes for comparing
trends among 3 primary study sites. Nest boxes may provide nesting opportunities
for numerous species of bird in our study area and are easily monitored (Newton
1994). Typically, nest boxes experience lower predation rates and higher survival
than natural cavities (Møller 1989, Nilsson 1984, Purcell et al. 1997) but nevertheless
can provide useful information for making inferences regarding natural
predator rates at a particular site.
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Field-Site Description
Our study took place from March to July of 2015 and 2016 at Conecuh National
Forest in Alabama. Conecuh National Forest is ~34,000 ha of Longleaf Pine forest
adjacent to Blackwater River State Forest in neighboring Florida. We established
3 study plots in similar, contiguous pine forest. The 3 plots were components of
a before–after, control–impact study evaluating ecological effects associated with
the attempted reintroduction of Drymarchon couperi Holbrook (Eastern Indigo
Snakes: Gitzen et al. 2017). Plot 1 consisted of Longleaf Pine trees aged ~80 yrs,
with a relative basal area for the stand of 22 m2 ha-1. Since year 2000, this plot has
been on a 2-yr fire-return interval. There were ~3 ha of maintained wildlife openings
interspersed throughout the pine forest. Plot 2 consisted of Longleaf Pine forest
aged ~80 yrs at a relative basal area of 13.8 m2 ha-1. However, until year 2016, the
basal area of this site had been 22.9 m2 ha-1 prior to forest thinning. Plot 2 contained
~11 ha of maintained wildlife openings. Similar to Plot 1, this site was placed on
a 2-yr fire-return interval starting in the year 2000. Finally, Plot 3 was aged 80 yrs
old, had a basal area of 18.4 m2 ha-1, contained 7 ha of wildlife openings, and was
on a fire-return interval of 3 yrs. Each of these 3 plots were located within the Blue
Spring Wildlife Management Area.
Methods
Nest boxes
In this study, we used artificial nest boxes to make inferences about the natural
predator assemblage and its effects on nesting birds; however, an extensive body
of literature exists regarding potential biases associated with this methodology (reviewed
in Lambrechts et al. 2010). We are therefore conservative when using the
data we collected from nest boxes to make conclusions about birds nesting in natural
cavities. We constructed nest boxes using untreated cedar fence boards. Each
box was 30 cm x 14 cm x 12 cm. We cut circular entrance holes of 3.8 cm, which
is the generally recommended diameter opening for nest boxes inteded for Sialia
sialis L. (Eastern Bluebird) but is also suitable for a wide array of other cavitynesting
birds. We made the top of each nest box hinged so we could easily survey
nest contents when necessary.
In February of 2015, we established 3 grids for placing nest boxes. Grids were
centered in each of three 2-km2 areas associated with a long-term study to determine
the effects of Indigo Snake reintroductions on the ecology of the Longleaf
Pine ecosystem. At the time of the study, only 1 of the 3 plots had experienced Indigo
Snake releases. We placed a total of 251 nest boxes in the 3 plots (n = 76, 87,
and 88, respectively, in each plot). We placed boxes ~50 m apart in approximate 10
x 10 grids, although the numbers of boxes in each site varied based on the boundaries
of our site and the presence of features such as roads, clearings, or waterbodies
that prevented the placement of boxes. Each box was mounted to the side of a tree
approximately 1.5–2 m off the ground. If a tree was not present at the determined
point location (~5% of the time), we hung boxes on metal garden poles ~1.75 m off
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the ground. When mounting boxes, we oriented them to avoid having branches and
vegetation within 1.5 m of the entrance hole that might dissuade bird colonization
or obscure the view from the cameras.
Nest monitoring
We checked all nest boxes for bird occupancy at least twice per month (min–max
= 5–17 days). When a box was determined to have an active nest in it—evidenced
by the presence of a fully or partially constructed nest, eggs, or active building behavior
by birds—we immediately placed a camera at the nest. The open understory
of this habitat allowed us to use motion-activated, infrared trail cameras (Bushnell
Aggressor Trophy Cam 20MP HD, Bushnell Outdoor Products, Overland Park, KS)
to monitor nests. We placed cameras on tripods or garden stakes ~5 m away from
each nest box. We programmed cameras to take a burst of 3 photographs every
time the motion trigger was activated. Each camera had a 32-GB memory card in it
capable of storing upwards of 30,000 photographs. We visited cameras every 5–9
days to replace batteries and download memory cards. We checked the status of the
nests during each visit by partially opening the lid of the nest box and using a mirror
to view the nest contents and condition. At each nest check, we noted the nest
contents (# eggs and/or nestlings, the presence of parents, the condition of the
nest) and attempted to age nestlings when appropriate. We removed cameras after
nests had been depredated or successfully fledged young. We considered a nest to
have fledged young when the nest was empty and relatively undisturbed during the
nest check closest to the estimated fledge time for the species. We then confirmed
fledging by reviewing the photographs. For each depredated nest, we reviewed the
photographs to determine predator identity, the time and date that predation occurred,
the duration of the predation event, as well as any additional details that
could be ascertained from photographs. Following depredation events in which
birds were killed, we swept the carcasses of birds from nest boxes but otherwise did
not clean out nest boxes between seasons. All field work was done under Auburn
University animal care and use protocol #2016-2036.
Data analysis
We identified 6 variables of interest for use in our analysis of nest survival.
Because predators may detect different cues or find more value in depredating
nests at different stages (egg or nestling), we included the stage of the nest in our
analysis. We included day of year as one of the variables in our analysis because
predators often have seasonal activity patterns (Sperry et al. 2008) . Relative to
those placed on garden poles, we hypothesized that boxes mounted on natural
trees might be easier for some predators (e.g., snakes, Flying Squirrels) to access,
or might be more often encountered by chance as the predators used trees to move
between the ground and the canopy, so we included the effect of mount type on
daily survival. The different avian species which nested in our boxes could experience
different daily survival rates, so we also included nesting species identity
as a variable. We examined the effect of year to account for potential yearly
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differences (e.g., weather) and plot ID to account for potential patch-level differences
in survival between study sites.
We first modeled overall daily nest survival as a function of these 6 variables,
using logistic exposure methods (Shaffer 2004) in R 3.3.2 (R Core Team 2016). We
examined 6 models, each including 1 of the above variables, and used AICC and
model weights (Burnham and Anderson 2002) to compare them with a global model
containing all variables, and an intercept-only (constant survival) model. For models
with considerable support (> 35% weight of evidence and ~ 2 ΔAICC units from
next competing model), we examined predictions and 95% confidenc e intervals.
As the data were collected in the field, it became increasingly clear that
Flying Squirrels were by far the most frequent nest predator in our study. We
conducted further analyses on predator class-specific predation probability on
a subset of nests for which the predator was known. We used a 1-way goodness-
of-fit test (in R 3.3.2) to confirm that a disproportionate number of the
predation events we observed were caused by Flying Squirrels. To explore
what factors potentially made predation by squirrels more likely, we examined
a multinomial model in SAS 9.4 (Cary, NC) using PROC LOGISTIC. In
this model, we classified the outcome of each daily exposure period as either
survive, depredated by Flying Squirrel, or depredated by another predator.
We used nest outcome as the response variable, with “survive” as the reference
category. We included egg or nestling stage and nest-box mount type (tree
or pole) as predictor variables. Because we had relatively few observations of
predators other than Flying Squirrels depredating nests, we limited our model
to just these 2 variables, which we hypothesized had the most potential to differentiate
what causes predation by different species. We present estimated
daily predation probabilities for the different groups of the predictor variables.
Results
We monitored 26 active avian nests (11 in 2016 and 15 in 2017), belonging
to 4 species including Eastern Bluebird, Poecile carolinensis Audubon (Carolina
Chickadee), Baeolophus bicolor L. (Tufted Titmouse), and Thryothorus ludovicianus
Latham (Carolina Wren) (Table 1). Twenty-one of the active bird nests
were in boxes mounted on trees, and 5 were in boxes mounted on poles. Of the 26
monitored nests, 5 successfully fledged young and 21 were completely depredated
Table 1. Summary of avian nests monitored with trail cameras at Conecuh National Forest, AL, during
the 2015 and 2016 nesting seasons. We filmed a total of 26 avian nests in artificial nest boxes for
a total of 390 exposure days. Overall, 21 nests were depredated and 5 successfully fledged young.
Species No. nests Exposure days No. fledged No. failed Daily survival rate
Carolina Wren 7 61 0 7 0.885
Carolina Chickadee 4 105 2 2 0.981
Eastern Bluebird 10 118 2 8 0.937
Tufted Titmouse 5 106 1 4 0.959
Total 26 390 5 21 0.946
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(Table 1). We identified Flying Squirrels (Fig. 1) as the predator responsible for 16
nest failures. We also determined ants, an unidentified bird of prey, and an unknown
rodent as being responsible for 1 nest failure each. We failed to identify the nest
predator responsible for 2 additional depredation events due to camera malfunction.
However, the condition of 1 of these nests (lid of box removed, nest heavily damaged)
suggested it was likely depredated by a Flying Squirrel.
In our analysis of nest survival using logistic exposure models (26 nests, n =
390 exposure days), the identity of the nesting species was the only model with
more weight than constant survival (Table 2). The estimated daily survival rate for
Carolina Chickadees was highest (0.981), while Carolina Wren daily survival was
lowest (0.885). Confidence intervals for all species overlapped (Fig. 2A), and the
difference between Carolina Chickadee and Carolina Wren nests was not significant
when adjusted for multiple comparisons (Tukey-adjusted P = 0.094).
We were able to use data from 24 nests (n = 379 exposure days), which were
either successful or depredated by known-identity predators, in our analyses of
predator class. Flying Squirrels were by far the most frequent nest predator, depredating
84% of nests where the predator identity was known (χ2 = 8.89, P = 0.003).
The effects of mount type and nesting stage were non-significant (P = 0.38 and P =
0.46, respectively) and confidence intervals overlapped broadly (Fig. 2B).
Figure 1. Glaucomys volans (Southern Flying Squirrel) was a major predator of bird nests
in nest boxes during the 2015 and 2016 avian nesting seasons.
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Flying Squirrels exclusively preyed on nests at night, with the earliest event
initiating at 2033 hrs and the latest beginning at 0209 hrs. Once a predation event
began, squirrels were always successful in accessing and destroying the contents
of nests; nest-defense behavior by adult birds was not documented (although we
cannot be assured it did not occur). Squirrels were responsible for the failure of 7
nests containing eggs and 9 nests containing nestlings. During 2 of the nest-predation
events, the Flying Squirrel killed the adult female bird (Eastern Bluebird and
Tufted Titmouse) in the nest box. Neither of the killed adults was eaten or partially
eaten by the squirrel. We found no evidence that nestlings killed by squirrels were
eaten either. However, eggs appeared to be eaten as only eggshells remained after
Table 2. Logistic exposure models of nest survival for cavity-nesting birds using artificial nest boxes
in Alabama, 2015–2016. Analysis includes all nest data (26 nests, n = 390 exposure days) from
successful nests and nests depredated by Southern Flying Squirrels, other identified predators, and
unknown predators.
Model k AICC ΔAICC wi
Nesting species 4 163.95 0.00 0.41
Constant survival 1 165.57 1.62 0.19
Mount type 2 166.28 2.33 0.13
Day of year 2 166.94 2.99 0.09
Nest stage 2 167.51 3.56 0.07
Year 2 167.54 3.59 0.07
Plot ID 3 168.72 4.77 0.04
Global 11 174.60 10.65 less than 0.01
Figure 2. (A) Estimated daily survival rate of bird nests in nest boxes by species in Conecuh
National Forest, AL, in 2015 and 2016. (B) Predicted daily predation rates from Glaucomys
volans (Southern Flying Squirrel) estimated from a multinomial model. Estimates were
generated for all nests (overall) as well as each level of the nest stage and box mount type
variables, while holding the other variable at its mean level.
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depredation. All predation events by squirrels resulted in complete loss of the brood
(when nestlings were present) or clutch (when eggs were present). Nest-predation
events varied from 1 min in duration to 144 min, with a mean of 37 min. Although
Flying Squirrels are social animals, we never saw more than 1 squirrel visit a bird
nest at the same time.
Discussion
Our results revealed that Flying Squirrels were major nest predators in artificial
nest boxes in this Longleaf Pine forest, accounting for 16 of 19 (84%) nest failures
where the predator identity was known. Flying squirrels have been identified as potential
predators of avian cavity nests (Laves and Loeb 1999, Miller 2002), but the
empirical data that exist suggests this species (typically considered to feed on mast
and seeds; Harlow and Doyle 1990) rarely prey upon nests (15 out of 1900 documented
nest failures; DeGregorio et al. 2016). Specifically, Flying Squirrels have
been documented preying on Mimus polyglottos L. (Northern Mockingbird) nests
in Florida (n = 4; Stracey 2011), Hylocichla mustelina Gmelin (Wood Thrush)
nests (n = 8; Williams and Bohall Wood 2002) in West Virginia, and the open-cup
nests of common shrubland and suburban birds in Ohio (n = 1; Rodewald and Kearns
2011) and Missouri (n = 2; Cox et al. 2012b). Furthermore, there has been little
evidence connecting Flying Squirrels to decreased avian nest success (Conner et al.
1996, Mitchell et al. 1999). In fact, experiments have shown that removal of Flying
Squirrels has relatively little influence on Red-cockaded Woodpecker nesting success,
with some birds successfully fledging young when they used cavities in the
same tree as active squirrel cavities (Conner et al. 1996, but see Laves and Loeb
1999). Given the high proportion of nest failures in our study attributed to Flying
Squirrels, it seems likely that this species has a measurable effect on avian breeding
success in this ecosystem.
The lack of diversity in the nest-predator assemblage we observed was also
surprising. Typically, nest-predator assemblages are highly diverse with even the
most common nest predators accounting for less than half of all observed nest predation
(DeGregorio et al. 2016, Reidy and Thompson 2012, Thompson and Burhans
2003). There are some exceptions, but they generally occur in climatic extremes
where biological diversity is relatively low. For example, 80% of observed bird
nest failure in Alaska was attributed to Alopex lagopus L. (Arctic Fox; Liebezeit
and Zack 2008), and Tamiasciurus hudsonicus Erxleben (Red Squirrel) caused 45%
and 85% of nest failure, respectively, in Northwest Territories and Alberta, Canada
(Ball et al. 2008).
Given that other studies in neighboring Georgia and Florida have shown relatively
high diversity of predator species (including raptors, snakes, and mammals;
e.g., Conner et al. 2010, Ellis-Felege et al. 2012, Stracey 2011), the high proportion
of nest failure due to Flying Squirrels documented here suggests they may be
a particularly important nest predator in managed southern pine forests, although
our inferential power is limited because we monitored nests in artificial cavities,
our absolute sample size was relatively low, and the complex ecology of the natural
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system (e.g., Blanc and Walters 2008) may result in surprising patterns. For example,
it has been suggested that Flying Squirrels may develop a search image for artificial
nest boxes and find them relatively easily (Miller 2002). The relatively high
density of nest boxes that we deployed may have made them even easier for Flying
Squirrels to detect. Further study of the ecology of the system is warranted to better
understand potential effects on avian assemblages and population demographics;
these studies may be particularly worthwhile given ongoing Eastern Indigo Snake
reintroductions in Conecuh National Forest. Although we did not document differences
among sites, the presence of Eastern Indigo Snakes (which prey on snakes
that eat Flying Squirrels; Rudolph et al. 2009), may eventually initiate a trophic
cascade with consequences for both Flying Squirrels and cavity-nesting birds.
Typically, nest boxes experience lower predation rates and higher survival than
natural cavities (Møller 1989, Nilsson 1984, Purcell et al. 1997). Consequently, the
nest survival rates we observed (~20% overall survival) were surprisingly low. It
remains unclear why Flying Squirrels were responsible for the failure of so many
nests. Although Flying Squirrels killed nestlings and adult birds, they rarely consumed
them, suggesting that the predatory behavior was not primarily motivated by
food. However, Flying Squirrels did consume eggs when they raided nests containing
them and so it is possible that adults and nestlings are simply killed as Flying
Squirrels search for eggs. Alternatively, the lack of natural cavities in managed
Longleaf Pine ecosystems (Newton 1994, Waters et al. 1990) may have forced Flying
Squirrels to usurp birds and take over the boxes. We added over 250 boxes to
the landscape at once, and relatively few of them were colonized by birds (< 6% per
year) or squirrels (3% on average occupied at any given day), so there should have
been no shortage of artificial cavities for squirrels to use. However, Flying Squirrels
often use multiple tree cavities for different purposes including nesting, roosting
(individually or communally), food storage, or as latrines (Brady et al. 2000,
Layne and Mendi 1994). Additionally, Flying Squirrels will often switch between
multiple boxes to reduce their ectoparasite risk (Hanski et al. 2000), which could
lead to squirrels using more nest boxes than would be anticipated based upon their
abundance. Several studies have demonstrated the dangers and costs of artificial
nest boxes for birds and suggested that in some situations these nesting structures
may act as ecological traps (Eadie et al. 1998, Gowaty and Bridges 1991, Klein
et al. 2007). Unfortunately, we were unable to concurrently monitor bird nests in
natural cavities within the study plots to serve as controls to assess a baseline nestpredation
rate.
Nocturnal nest predation, such as by Flying Squirrels, can be dangerous to
incubating or brooding adult birds. Reidy et al. (2009) estimated that 14.6% of
breeding female Setophaga chrysosparia P.L. Sclater & Salvin (Golden-cheeked
Warbler) were killed on nests by nocturnal snakes. Cavity-nesting birds are thought
to be especially vulnerable to nocturnal nest predators (Fendley 1980, Hensley and
Smith 1986), and we observed Flying Squirrels killing at least 2 brooding adult
female birds (Eastern Bluebird and Tufted Titmouse) while depredating nests. Flying
Squirrels always preyed on nests at night, likely reducing the ability of birds
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to defend their nest or escape. Although not closely related to Flying Squirrels,
Petaurus breviceps Waterhouse (Australasian Sugar Gliders) are morphologically
and ecologically similar and have been documented depredating cavity nests of several
rare birds, including the critically endangered Lathamus discolor Shaw (Swift
Parrot; Stojanovic et al. 2014). Nest predation pressure by Sugar Gliders, during
which adult females are often killed, has been identified as a severe threat to Swift
Parrot populations, potentially causing collapse within 3 generations (Heinsohn et
al. 2015). While the 4 avian species we studied are not generally considered of conservation
concern and unlikely to experience range-wide population declines due to
nocturnal predation, predators that remove reproductive females from a population
have the potential to cause devastating effects on small or declining populations
such as the Red-cockaded Woodpecker (Heinsohn et al. 2015, Reidy et al. 2009),
and their effects should be considered by biologists tasked with managing imperiled
species, especially when artificial nest cavities are being considered as a conservation
action. Additionally, before nest boxes are placed into systems, researchers and
managers should consider the potential unintended consequences of boxes.
Our identification of Flying Squirrels as major nest predators of birds using
artificial next boxes in this system was surprising and highlights the need for a better
understanding of Flying Squirrel ecology to determine what brings them into
contact with nests, as part of the larger goal of developing a clearer picture of the
identity of nest predators at cavity nests across North America. Predators of cavity
nests are likely quite different from those of open-cup nests. Because of the vulnerability
of birds in cavities to predators, understanding predator identity will likely
be an important step in conserving cavity-nesting birds.
Acknowledgments
Many people assisted in building the nest boxes including Jason Gleditsch, Brittney
Graham, Dylan O’Hearn, Valerie Buxton, Patrick Wolff, and David Sperry. Sierra and James
Stiles provided valuable assistance in hanging boxes. We thank Jasmine Parham, Hunter
Walters, and Kryštof Chmel for their work monitoring nest boxes. This project is part of a
larger effort to reintroduce the Eastern Indigo Snake to Conecuh National Forest and monitor
the ecological impacts. Jim Godwin provided essential support with logistics and
oversight of work associated with the snake reintroductions. We also thank Derek Colbert
for providing valuable information about the forest management of the study areas. During
this study, the project was largely funded by the Alabama Department of Conservation
and Natural Resources and in cooperation with the United States Fish and Wildlife Service
and United States Forest Service. Funding for this project was provided by ERDC EQI Direct
funding PE/Project/Task: 62720/896/04
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