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Survival and Cause-specific Mortality of Adult Female Eastern Wild Turkeys in a Bottomland Hardwood Forest
Michael E. Byrne and Michael J. Chamberlain

Southeastern Naturalist, Volume 17, Issue 2 (2018): 345–356

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Southeastern Naturalist 345 M.E. Byrne and M.J. Chamberlain 22001188 SOUTHEASTERN NATURALIST 1V7o(2l.) :1374,5 N–3o5. 62 Survival and Cause-specific Mortality of Adult Female Eastern Wild Turkeys in a Bottomland Hardwood Forest Michael E. Byrne1,* and Michael J. Chamberlain2 Abstract - Meleagris gallopavo (Wild Turkey) population dynamics are greatly influenced by female survival, and high female-survival rates may offset low reproductive rates and maintain stability in populations characterized by low productivity. Additionally, reproduction may incur a cost to annual survival, given the physiological stress associated with breeding, and predation risks associated with incubation and brood-rearing. We used radio-telemetry and known-fate modeling to quantify annual survival and identify mortality causes of 54 adult female Meleagris gallopavo ssp. silvestris (Eastern Wild Turkey) tracked during 2002–2004 and 2007–2010 in a population characterized by low productivity in a bottomland hardwood forest in Louisiana. We detected 31 mortalities in which predation was the leading cause (87%), primarily attributed to Canis latrans (Coyote) and Lynx rufus (Bobcat). We estimated an annual survival rate of 0.58 (95% CI = 0.47–0.68) with no evidence of seasonal variation. This level of survival appeared to be sufficient to offset low productivity; the population was considered healthy and stable during the study period. Annual survival rates of females that incubated a nest were lower than reproductively inactive females, although confidence intervals overlapped considerably. The mechanisms underlying survival differences between reproductive classes were not entirely clear because survival of nesting females did not greatly decrease during incubation and brood-rearing seasons relative to non-nesters as would be expected under the hypothesis of increased predation risk during reproduction periods. Future studies should aim to better elucidate the links between reproduction and survival in Eastern Wild Turkey populations because this information will have important management ramifications in the southeast, where region-wide declines in productivity have been observed. Introduction Survival of adult female Meleagris gallopavo L. (Wild Turkey) is an important parameter influencing Wild Turkey population dynamics because adult females have a large influence on productivity and recruitment (Roberts and Porter 1996, Vangilder 1992). Survival and cause-specific mortality of female Wild Turkeys has been widely studied across the species’ range (e.g. Humberg et al. 2009, Kurzejeski et al. 1987, Miller et al. 1998, Nguyen et al. 2003, Roberts et al. 1995, Wright et al. 1996). Such studies are valuable to identify primary sources of mortality (e.g., harvest or predation) as well as seasonal variations in survivorship, which can guide management actions. Although the results of studies of Wild Turkey survival are often specific to the study area and conditions during the study p eriod, the combined 1School of Natural Resources, University of Missouri, Columbia, MO 65203. 2Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602. *Corresponding author - Manuscript Editor: Barry Grand Southeastern Naturalist M.E. Byrne and M.J. Chamberlain 2018 Vol. 17, No. 2 346 inferences from many studies can help inform a more complete understanding of the dynamics of survival across a range of habitats and environmental conditions. An aspect of female Wild Turkey life history that relatively few survival studies have attempted to explicitly quantify (but see Collier et al. 2009, D.A. Miller 1998, M.S. Miller et al. 1995) is the link between survival and reproduction. Theory would suggest an inverse relationship between population-level survival and reproduction as populations grow in a density-dependent manner (Guthery and Shaw 2013), and it has been suggested that high female survival may offset poor productivity to maintain stability in Wild Turkey populations (Byrne et al. 2015, Vangilder et al. 1987). Evidence suggests that in the last decade, Meleagris gallopavo ssp. silvestris Vieillot (Eastern Wild Turkey, hereafter, Turkey) populations have begun to stabilize across much of the southeastern US, following several decades of rapid population growth resulting from successful restoration projects (Byrne et al. 2015). As populations have stabilized, annual summer brood surveys conducted by state agencies have indicated a general region-wide decrease in productivity, and annual female survival has generally increased (Byrne et al. 2015). There are several potential causes for a trade-off between reproduction and survival. Incubation and brood-rearing activities may increase susceptibility to predation, leading to greater mortality during reproductive periods (Miller and Leopold 1992, Miller et al. 1998, Pollentier et al. 2014, Speake 1980). Several studies have observed seasonal variation in survival, with lowest survival occurring during periods associated with reproductive activity (Hubbard et al. 1999, Little et al. 2016, Palmer et al. 1993, Vander Haegen et al. 1988, Wright et al 1996). In addition to increased predation risk, physiological costs associated with reproduction, such as decreased immune efficiency (Cox et al. 2010, Hanssen et al. 2005, Harshman and Zera 2007), may affect survival beyond the reproductive period. As such, reproduction may incur a survivorship cost, and reproductively active females could be expected to exhibit lower rates of annual survival than reproductively inactive females. Collier et al. (2009) found lower survival rates of reproductively active Meleagris gallopavo ssp. intermedia Sennett (Rio Grande Turkey) on the Edwards Plateau of Texas; however, the link between survival and reproduction has been more ambiguous in studies of Eastern Wild Turkeys. In Georgia, Little et al. (2016) found evidence that females that incubated a nest had somewhat higher survival during spring than those that did not, but they did not perform statistical comparisons of annual survival rates. In Mississippi, Miller et al. (1998) found no differences in annual survival between reproductively active and inactive females, although nesting birds were more prone to predation than non-nesters. Miller et al. (1998) suspected a high cost of reproduction during the brood-rearing period for females raising young, but did not have sufficient evidence to say so definitively. By addressing knowledge gaps in regards to the relationship between female Eastern Wild Turkey survival and reproduction, this study will help inform management of Wild Turkeys in the southeastern US in the face of a large-scale population shift (Byrne et al. 2015), and guide future research. Our specific objectives were Southeastern Naturalist 347 M.E. Byrne and M.J. Chamberlain 2018 Vol. 17, No. 2 to (1) estimate annual and seasonal female survival rates, (2) identify and quantify specific causes of mortality, and (3) investigate whether reproductively active females had lower survival than reproductively inactive females for a population of Eastern Wild Turkeys within a bottomland-hardwood ecosystem in south-central Louisiana. At the time of our study, before the catastrophic flooding in 2011 (Chamberlain et al. 2013), Turkeys on our study site were abundant and the population was stable based on annual harvest rates of males (Louisiana Department of Wildlife and Fisheries 2010). This population was also characterized by one of the lowest per-capita female nesting success rates ever reported (Byrne and Chamberlain 2013). Therefore, we expected that compared to other studies, female survival of this population would be relatively high in order to maintain the population despite low productivity. Additionally, we hypothesized that annual survival of reproductively active birds would be less than that of reproductively inactive birds, and that reproductively active and inactive birds would have different patterns of seasonal survival. Specifically, we hypothesized that survival during the nesting and broodrearing seasons would be lower for reproductively active females because of the increased predation risk associated with those activities. Field-site Description We conducted our research on a 17,243-ha tract (hereafter, Sherburne) of bottomland hardwood forest in Iberville, St. Martin, and Point Coupee Parishes, Louisiana, located in the Atchafalaya floodway system. Sherburne included Sherburne Wildlife Management Area, managed by the Louisiana Department of Wildlife and Fisheries; Bayou des Ourses, managed by the US Army Corps of Engineers; and the Atchafalaya National Wildlife Refuge, managed by the US Fish and Wildlife Service. Approximately 770 ha of private lands are interspersed among state and federal lands. Sherburne is bordered on the south by Interstate 10, on the north by Highway 190, on the west by the Atchafalaya River, and on the east by the East Protection Guide Levee. Sherburne was 96% forest, 2% forest openings, and 2% open water, based on classification of landcover types from digital orthophoto quarter-quadrangles (Byrne and Chamberlain 2013). Common overstory species included Populus deltoides W. Bartram ex Marshall (Eastern Cottonwood), Quercus texana Buckley (Nuttall’s Oak), Q. nigra L. (Water Oak), Q. lyrata Walter (Overcup Oak), Liquidambar styraciflua L. (Sweetgum), Celtis laevigata Willdenow (Sugarberry), Fraxinus pennsylvanica Marshall (Green Ash), Salix nigra Marshall (Black Willow), and Taxodium distichum (L.) Rich. (Bald Cypress). Approximately 40% of Sherburne experiences annual persistent flooding and has limited understory vegetation. Forest openings consisted of wildlife-food plots, rights-of-way (electric and natural gas) maintained through mowing and herbicide application, levees, and natural regeneration following forest harvesting. Mean annual high and low temperatures for the region were 27.8 °C and 8.9 °C, respectively, and average annual rainfall was 155.4 cm. For a more detailed description of the study site see Byrne and Chamberlain (2013). Southeastern Naturalist M.E. Byrne and M.J. Chamberlain 2018 Vol. 17, No. 2 348 Methods We captured female Turkeys using cannon nets baited with corn at sites distributed throughout our study area during summer (June–August) from 2001 to 2003, and 2007 to 2008. We trapped during summer because Turkeys would not respond to bait sites during winter; thus, winter capture opportunities would have been practically non-existent. We fitted each captured female turkey with a standard, serially numbered aluminum leg-band (National Band and Tag Company, Newport, KY) and a 75-g (≤3% body weight) mortality-sensitive radiotransmitter (Advanced Telemetry Systems, Isanti, MN), attached backpack-style (Kenward 1987). We released all Turkeys at capture sites immediately following processing. All capture and handling procedures were covered under Louisiana State University Agricultural Center Institutional Animal Care and Use Protocol number AE2010-09. We monitored Turkeys via radio telemetry throughout the year using a 3-element Yagi antenna and an ATS R4000 receiver (Advanced Telemetry Systems, Isanti, MN). We triangulated ≥3 locations weekly for each individual from September to early February and ≥1 location daily for the remainder of the year to capture more detailed data during the reproductive seasons. We monitored Turkeys during 2002–2004, and 2007–2009. Data from females monitored during 2002–2004 was previously published in Wilson et al. (2005), although, in this manuscript, we have reanalyzed data from all study years. Field methodologies used during all years were identical unless otherwise noted. When we detected a mortality signal, we attempted to recover the radio as soon as possible and determine the cause of death. Incubating birds often activated the mortality signal, so we did not investigate mortality signals for 29 days following the initiation of a mortality signal between 1 April and 15 May during 2008 and 2009 so as not to disturb females that may have been nesting. We grouped mortalities into 4 categories based on condition of the carcass and visible sign in the immediate area. We classified mortalities as (1) Lynx rufus (Schreber) (Bobcat) predation if the carcass was cached, or if we found Bobcat tracks or scat near the kill site; (2) canid (either Canis latrans Say [Coyote] or Canis lupus familiararis L. [Domestic Dog]) predation if we found canid tracks, scat, or fur at the kill site; as (3) unknown predation, if predation was evident but we found no identifiable predator sign; and as (4) unknown mortality when scavengers had destroyed the carcass before recovery, or if there was no obvious sign of predation or injury. We partitioned the year into 3 biologically meaningful seasons based on observations of female nesting chronology on Sherburne (Byrne and Chamberlain 2013). The nesting season ran from 9 March to 9 May, based on back-dating 2 weeks from the earliest recorded nest-initiation date until the latest known re-nest initiation date. The nesting-season period covered most pre-incubation movements, egg laying, and incubation activities. We defined the brood-rearing season as the period from10 May to 30 September, and the fall/winter season as 1 October–8 March. The biological year ran from 9 March to 8 March. We estimated survival using known-fate models in program MARK (White and Burnham 1999). We used the above-mentioned biological seasons as the sampling Southeastern Naturalist 349 M.E. Byrne and M.J. Chamberlain 2018 Vol. 17, No. 2 occasion. We excluded from our analyses individuals that died within 1 week of capture to remove any bias that might result from capture mortality and censored any individuals that experienced radio-failure during the interval in which radio contact was lost. We assumed constant survival across years and allowed individuals that survived 1 year to reenter the analysis the following year to account for unbalanced sample sizes among years and ensure adequate sample sizes in each season. Thus, we shortened the entire capture history to 3 occasions (representing the 3 seasons). We treated each year that a Turkey was monitored as a new-capture history and added as a separate row of data. Entry was staggered during the first year a Turkey was monitored because all captures occurred during the brood-rearing season. Although we recognize potential biases associated with pooling across years, low sample sizes in particular years required that we adopt this methodology. All females were captured during summer (June–August); thus, we did not separate age classes because all individuals were either adults ≥ 1 year old or subadults being recruited into the adult population. To determine if survival varied seasonally, we developed 2 candidate models. The first model held survival constant across seasons, whereas the second allowed survival to vary across seasons. We used Akaike’s information criterion adjusted for small sample sizes (AICc ) and Akaike model weights (wi ) to evaluate and choose the most parsimonious model (Burnham and Anderson 2002). We used the most parsimonious model to derive an estimate of annual survival. To assess the influence of reproduction on survival, we estimated seasonal and annual survival in MARK as described above for Turkeys in which reproductive activity was known for a given year. As such, females were only introduced into the analysis during the nesting season following the summer in which they were captured. We excluded from this analysis females that experienced a mortality event or radio-failure between summer capture and 9 March of the following year. We grouped individuals into 2 categories based on reproductive activity within a given year; reproductively active Turkeys reached the stage of nest incubation, and reproductively inactive turkeys did not incubate a nest. We developed a set of candidate models to determine how season and reproductive activity affected survival and used AICc, ΔAICc, and Akaike weights (wi ) to evaluate model performance. Results We estimated survival for 54 female Turkeys monitored from 11 February 2002 to 27 August 2004, and 8 June 2007 to 9 May 2010. We recorded 31 mortalities during the course of the study and located all carcasses. Predation accounted for the greatest percentage of observed mortalities (87.1%) and included predation by canids (n = 7), Bobcats (n = 5), and unknown predators (n = 15). We could not determine cause of death for 4 females. In 2 instances, the carcass exhibited no obvious signs of injury, and in 2 cases the carcass was destroyed by scavengers before we could recover it. The 2 carcasses destroyed by scavengers prior to recovery represented mortality signals detected during the 2008–2009 nesting seasons that we did not investigate immediately to avoid disturbing an incubating female. Southeastern Naturalist M.E. Byrne and M.J. Chamberlain 2018 Vol. 17, No. 2 350 There was little evidence of seasonal variation in survival; the model that held survival constant had considerable support relative to the model of seasonal variation (ΔAICc = 4.03, wi = 0.88). Annual survival was estimated at 0.58 (95% CI = 0.47–0.68). Using data from 39 females (25 reproductively active, 14 inactive) for which we knew nesting status from the 2002–2004, 2008, and 2009 nesting seasons, the best model of survival considered nesting status as the only explanatory variable (Table 1). The model that considered only season as an explanatory variable was within 2 AIC units of the top model (Table 1), but further investigation revealed that confidence intervals of parameter estimates for all seasons included zero, indicating season was an uninformative parameter (Arnold 2010). The annual survival estimate of reproductively inactive females (0.49; 95% CI = 0.32–0.65) was greater than reproductively active females (0.30; 95% CI = 0.14–0.52), although confidence intervals overlapped considerably. There was little evidence for seasonal variation, but estimates from the model that included reproductive status and season indicated a tendency towards lower survival for both groups during the brood-rearing season (Table 2). Discussion Predation was the primary cause of mortality for female Turkeys on Sherburne, consistent with the literature on the species (Hubbard et al. 1999, Humberg et al. 2009, Miller et al. 1998, Wright et al. 1996). Bobcats and Coyotes were responsible Table 1. Model-selection results of known-fate survival models for adult female Eastern Wild Turkeys of known reproductive status (reproductively active females incubated a nest) during 2002–2004, and 2008–2009 on Sherburne Wildlife Management Area, Louisiana. K = number of parameters, AICc = Akaike’s information criterion adjusted for small sample size, ΔAICc = difference in AICc relative to smallest value, wi = AICc weight, RA = reproductive activity, and S = season (nesting, brood-rearing, fall/winter). Model K AICc ΔAICc wi RA 2 131.51 0.00 0.564 S 3 133.49 1.99 0.209 RA + S 4 133.57 2.07 0.201 RA × S 6 137.63 6.12 0.026 Table 2. Season survival probabilities (95% CI) for female Eastern Wild Turkeys with known reproductive status during 2002–2004, and 2008–2009 on Sherburne Wildlife Management Area, LA, based on known-fate survival models. We defined seasons as nesting: 9 March–9 May; brood-rearing: 10 May–30 September; and fall/winter: 1 October–8 March. Non-nesting birds did not incubate a nest, nesting birds reached nest incubation Season Non-nesting females Nesting females Nesting 0.80 (0.70–0.90) 0.71 (0.53–0.89) Brood-rearing 0.75 (0.59–0.91) 0.65 (0.47–0.83) Fall/winter 0.78 (0.64–0.92) 0.68 (0.48–0.88) Southeastern Naturalist 351 M.E. Byrne and M.J. Chamberlain 2018 Vol. 17, No. 2 in all cases in which a predator could be identified, and both species are often cited as important predators of Wild Turkeys throughout their range (Chamberlain et al. 1996, Miller and Leopold 1992, Speake 1980, Wright et al. 1996). In some areas in North America, hunting (legal and illegal) has also been shown to be an important cause of female mortality (Kimmel and Kurzejeski 1985, Vangilder and Kurzejeski 1995, Wright et al. 1996); however, there is no legal either-sex fall hunting season on Sherburne, and there was no evidence of poaching during this study. To place our survival estimates in the context of previous studies, we reviewed the literature for studies that reported annual survival estimates of female Eastern Wild Turkeys. To make meaningful comparisons, we only considered studies that used robust statistical methods (Murray 2006) to derive survival estimates from radiotelemetry data and excluded studies of introduced populations on the northern edge of the eastern subspecies range (e.g. Nguyen et al. 2003). If a study spanned multiple years and reported survival for each individual year (e.g. Miller et al. 1998), we calculated a mean annual survival estimate. In total, we identified 14 studies appropriate for comparison with our data (Table 3). Annual survival on Sherburne was within the range of that reported in the literature for Eastern Wild Turkeys and was close to the average of all studies (0.59; Table 3). Given the stability of the Wild Turkey population in our sampling area for the duration of our study (Louisiana Department of Wildlife and Fisheries 2010; N. Stafford III, Louisiana Department of Wildlife and Fisheries, Baton Rouge, LA, pers. comm.), an annual survival rate of 0.58 appears to have been sufficient to maintain the population despite very low reproductive output (Byrne and Chamberlain 2013). Annual survival on Sherburne was higher than the 0.44 annual survival rate Vangilder et al. (1987) suggested was required to offset low per-capita female reproductive success. Assuming that immigration and emigration are minimal, a population can remain stable as long as annual mortalities are compensated for by Table 3. Studies reporting annual survival estimates of female Wild Turkeys based of radiotelemetry data. Studies are ordered from lowest to highest annual-survival estimate. Study Location Mean annual survival Kurzejeski et al. 1987 Missouri 0.435 Roberts et al. 1995 New York 0.498 Miller et al. 1998 Mississippi 0.509 Pollentier et al. 2014 Wisconsin 0.510 Pack et al. 1999 Virginia/West Virginia 0.520 Wright et al. 1996 Wisconsin 0.527 Vangilder and Kurjezeski 1995 Missouri 0.537 Little et al. 2016 Georgia 0.550 Vangilder and Krzejeski 1995 Missouri 0.558 This study Louisiana 0.580 Hubbard et al. 1999 Iowa 0.676 Reynolds and Swanson 2010 Ohio 0.678 Palmer et al. 1993 Mississippi 0.683 Moore et al. 2010 South Carolina 0.740 Humberg et al. 2009 Indiana 0.777 Southeastern Naturalist M.E. Byrne and M.J. Chamberlain 2018 Vol. 17, No. 2 352 annual recruitment into that adult population (Pulliam 1988). When productivity is low, recruitment could be accomplished if females are able to survive to attempt reproduction over multiple seasons, as this should increase the probability of a female successfully raising ≥ 1 brood in her life. We believe this to have been the case on our study area. One female in this study, originally captured during summer 2003, was tracked through the fall/winter of 2004 when the first part of the study concluded. We captured this female again during the summer of 2007 and fitted her with a new radio transmitter, which unfortunately stopped working in the fall of that year. Given that this female was ≥ 1 year old when originally captured in 2003, she lived at least 5 y. One female captured as an adult in the summer of 2002 was killed by a predator in summer of 2004, placing her life span at ≥ 3 years, and another captured in summer of 2007 was still alive as of May 2010, placing her life span at ≥ 4 y. Of the 54 females monitored in this study , 26 provided > 1 y of data. Our trapping occurred in summer; thus, all individuals we radio-tagged were >1 y old at the time of capture. Unlike most studies assessing survival of female Wild Turkeys, we did not include juveniles in our analysis. The majority of studies that attempted to quantify survival in adults and juveniles found no difference, and subsequently combined age classes in their analysis (Little et al. 1990, Reynolds and Swanson 2010, Roberts et al. 1995, Vangilder and Krzejeski 1995). Thus, we are confident that our results are comparable to those reported in other studies. One exception was Hubbard et al. (1999), who found that juveniles had higher survival rates than adults. If it is true that juvenile survival is higher on Sherburne, then our annual survival estimates, which are based only on the adult females, may be somewhat low relative to the population as a whole (i.e., if all age classes had been included). Although seasonal variability in female survival has been reported in some studies (Hubbard et al. 1999, Nguyen et al. 2003, Palmer et al. 1993, Pollentier et al. 2014, Vander Haegen et al. 1988, Wright et al. 1996), it is not universally observed across the eastern subspecies’ range (Humberg et al. 2009, Kurzejeski et al. 1987, Miller et al. 1998, Roberts et al. 1995). Comparing seasonal survival rates across studies is tenuous because there is no standard in defining seasons and, how researchers chose to delineate seasons can vary considerably among studies. Nonetheless, the overall lack of consistency across studies seems to indicate that seasonal variation in survival is influenced by site-specific conditions such as the local predator community, habitat characteristics, and landscape structure and its influence on predation risk at certain time periods (Chamberlain et al. 1996, Thogmartin and Schaeffer 2000) or weather conditions, such as deep snow in winter (Healy 1992). Our findings suggest that local conditions on Sherburne during the study period were consistent enough not to significantly alter survival probability for females through the annual cycle. It is important to consider that we were forced to combine years in our analysis due to sample-size constraints for some years of the study. As such, it is conceivable that survival within seasons may have varied among years based on temporal changes in biotic and abiotic factors, and we would not have been able to detect such variation. Southeastern Naturalist 353 M.E. Byrne and M.J. Chamberlain 2018 Vol. 17, No. 2 Our findings supported our hypothesis that reproductively active females would have lower annual survival rates than inactive females; however, we found no evidence of seasonal differences in survival between reproductive classes. If increased predation during vulnerable reproductive activities were solely responsible for the observed difference in annual survival, we would have expected to see reduced survival during one or both of the reproductive seasons (nesting and brood-rearing) for reproductively active females relative to reproductively inactive females. Rather, reproductively active females exhibited survival ~10% lower than reproductively inactive females during all seasons. Thus, while our data indicate that reproduction incurred a cost to annual survival, the exact mechanisms underlying this observation are not readily apparent. Albeit anecdotal, we observed evidence, as have others (Miller et al. 1998, Palmer et al. 1993, Speake 1980) that mortality risk during brood-rearing is greater for females that successfully hatch a brood. We noted that 3 females that successfully hatched young were killed by predators within 5 d of hatching, before poults could fly and when the female was forced to ground roost. Unsuccessful nesting females should functionally behave as reproductively inactive females during this time and not encounter risks associated with caring for a brood. Where sample sizes are sufficient, future work should distinguish how survival varies between females that do not incubate a nest, females that reach nest incubation but fail to hatch any young (due to nest destruction, abandonment, or adult mortality), and females that successfully hatch young. For example, Collier et al. (2009) found that number of days spent incubating a nest was the most important determinant of breedingseason survival for female Rio Grande Turkeys on the Edwards Plateau of Texas, with survival probability negatively correlated with incubation time. No such studies exist in regards to Eastern Wild Turkeys. Reproduction does seem to incur a survival cost for female Wild Turkeys, yet it is clear that more work must be done to determine the exact mechanisms by which survival and reproduction are related, and investigations into the nature of this relationship represent an interesting course for future research. Such research is especially prescient in the southeastern US, where state wildlife agencies are grappling with trying to understand region-wide decreases in productivity, and its potential effect on population densities (Byrne et al. 2015). Moving forward, understanding the connections between reproduction and survival would inform more-accurate population-dynamic models, provide insight into what population parameters are important to monitor, and guide potential management of restored Wild Turkey populations. Acknowledgments We thank W. Wilson, R. Temple, N. Wright, S. Kennedy, and numerous volunteers for assistance with trapping and data collection. We thank the staff of the Louisiana Department of Wildlife and Fisheries (LDWF) for logistical support during the study. Funding and support were provided by LDWF, the National Wild Turkey Federation (NWTF), the Louisiana Chapter of NWTF, the School of Renewable Natural Resources at Louisiana Southeastern Naturalist M.E. Byrne and M.J. Chamberlain 2018 Vol. 17, No. 2 354 State University (LSU), the LSU Agricultural Center, the Warnell School of Forestry and Natural Resources at the University of Georgia, and the School of Natural Resources at the University of Missouri. Literature Cited Arnold, T.W. 2010. Uninformative parameters and model selection using Akaike’s information criterion. Journal of Wildlife Management 74:1175–1178. Burnham, K.P., and D.R. Anderson. 2002. Model selection and multimodel inference: A Practical Information-Theoretic Approach. 2nd Edition. Springer-Verlag, New York, NY. 488 pp. Byrne, M.E., and M.J. Chamberlain. 2013. 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