Managers often use mechanical disturbance in conjunction with, or in place of, prescribed fire to maintain pyrogenic plant communities in the southeastern United States. However, information on the effects of mechanical fire-surrogates on disturbance-dependent wildlife is lacking. The Florida scrub-jay Aphelocoma coerulescens is an endemic bird species reliant on Florida scrub, a pyrogenic shrubland plant community narrowly distributed on sandy ridges in peninsular Florida. Ocala National Forest in north central Florida supports the largest remaining population of Florida scrub-jays, and historically, maintenance of most scrub habitat at the site is through the commercial harvest (clearcutting) of mature sand pines Pinus clausa. Recently, a habitat restoration program established Scrub-Jay Management Areas by converting clearcut stands to scrub maintained in an early-successional condition by prescribed fire. We studied Florida scrub-jays in Scrub-Jay Management Areas (2016–2023) to better understand how family-group density changed over time since fire management compared with time since harvest in clearcut stands. In scrub treated with prescribed fire, Florida scrub-jay family-group density increased more rapidly postdisturbance and was consistently higher than in clearcut stands. Based on model predictions, the maximum mean density of family groups occurred at 8.5 y postfire (11.8 family groups/41 ha) in Scrub-Jay Management Areas and 6.2 y postharvest (5.5 family groups/41 ha) in clearcut stands. Our study provides the first quantitative data on the response of Florida scrub-jay populations to new forest management practices in this large and critically important population. These data provide an essential component for developing population models for Ocala National Forest under current conditions and for modeling the potential effects of future management decisions.

The Florida scrub-jay Aphelocoma coerulescens is an endemic bird species with a small and fragmented range in peninsular Florida (Woolfenden and Fitzpatrick 1996; U.S. Fish and Wildlife Service [USFWS] 2019a, 2019b). The species depends on Florida scrub, a narrowly distributed shrubland plant community that occurs on nutrient-poor sandy ridges and is maintained in a treeless state by periodic fire or mechanical treatment (Myers 1990; Florida Natural Areas Inventory [FNAI] 2010; Florida Fish and Wildlife Conservation Commission [FWC] 2019). Habitat loss, habitat fragmentation, and challenges with fire management have resulted in widespread Florida scrub-jay population declines (USFWS 2007, 2019a, 2019b). The USFWS (1987) listed the Florida scrub-jay as threatened in 1987, pursuant to the U.S. Endangered Species Act (ESA 1973, as amended). The species is a cooperative breeder, with extended family groups including two to eight individuals (Woolfenden and Fitzpatrick 1996). Most extant Florida scrub-jay populations contain fewer than 25 family groups and may be unlikely to persist over the long term (USFWS 2019a, 2019b).

The importance of periodic fire for Florida scrub-jays in Florida scrub has been well established (Fitzpatrick et al. 1991; Breininger et al. 2002, 2014a, 2014b, 2018). The optimal vegetative structure includes shrubs of medium height (1.2–1.7 m) and open sandy patches for caching acorns (Breininger 1992; Breininger and Carter 2003; Breininger and Oddy 2004; Breininger et al. 2014b; FWC 2019). On the central scrub ridges of southern Florida, Florida scrub-jay demographic rates decline in areas unburned for 20 y or longer (Woolfenden and Fitzpatrick 1984). However, scrub-jays may require more frequent fire in Atlantic coastal scrub, sometimes at intervals less than 5 y (USFWS 2006). Site-specific differences in soils and vegetative structure and composition alter responses to fire, making it challenging to generate a species-wide recommendation for the optimal fire return interval (Cox et al. 2020; Breininger et al. 2018; FWC 2019). Maintaining fire management strategies that optimize Florida scrub-jay occupancy and reproduction can be difficult, especially in areas dominated by sand pine (Pinus clausa) where fires can be difficult to control (Doren et al. 1987; Roberts and Cox 2000; FWC 2019). Land managers are often challenged by suboptimal burning conditions and as a result, much of the potentially suitable Florida scrub-jay habitat remains overgrown (Cox et al. 2020).

Managers face challenges in their attempts to integrate mechanical clearing with fire to mimic natural disturbance regimes for fire-dependent wildlife (e.g., Menges and Gordon 2010; Steen et al. 2013; Stephens et al. 2019). For Florida scrub-jays, mechanical clearing of pines is often used to restore scrub at sites where trees have become too large to manage safely with prescribed fire (Menges and Hawkes 1998; FWC 2019). However, mechanical tree harvesting may lead to increased soil disturbance, contribute to the spread of invasive plants, or reduce the efficiency of future fires (Menges and Gordon 2010; Weekley et al. 2011). Thus, additional research is needed to understand how Florida scrub-jay occupancy and productivity compare between sites managed by mechanical treatments or fire.

Ocala National Forest (hereafter Ocala NF) in north central Florida supports the largest remaining Florida scrub-jay population, one of only a few large populations with a low probability of extinction within 100 y (USFWS 2007). Ocala NF encompasses approximately 91,000 ha of scrub and sand pine plant communities that are managed for multiple objectives including commercial forest products, wildlife habitat, and recreation. The majority of potential habitat for Florida scrub-jays at Ocala NF has been historically maintained through commercial harvest of mature sand pine forest (U.S. Forest Service [USFS] 1999: Appendix E; Hinchee and Garcia 2017). A recent amendment to the Ocala NF Forest Management Plan (USFS 2009) established a habitat restoration program to increase the amount of Florida scrub-jay habitat by converting 20,982 ha of sand pine plantations to new Scrub-Jay Management Areas (SJMAs; Hinchee and Garcia 2017) that will be maintained as early successional scrub primarily through prescribed fire.

Relationships between habitat and landscape variables and the occupancy, relative abundance, and productivity of Florida scrub-jays at Ocala NF have been quantified in sand pine scrub after clearcuts (e.g., Beatty 2019; Miller and Shea 2021), but not in sand pine scrub managed with fire. Implementation of the SJMAs presents a unique opportunity to compare the response of Florida scrub-jays to management with and without fire at the same location. Thus, the primary objectives of this study were 1) to determine how the density of Florida scrub-jays changes with stand age (i.e., time since fire) within SJMAs and 2) to compare that pattern with existing data from clearcut stands of similar ages (i.e., time since clearcut). These data will provide a better understanding of how Florida scrub-jays respond to different management practices and facilitate rigorous population estimation for the entire Ocala NF population.

Ocala NF encompasses 147,622 ha across Lake, Marion, and Putnam counties in north central Florida and is bordered on the west by the Ocklawaha River and on the east by the St. Johns River. Approximately two thirds of Ocala NF is made up of the largest contiguous scrub in Florida that is characterized by nutrient-poor sandy soils (Astatula-Paola association) on dune-like ridges that formed during the Pleistocene (Myers 1990). Florida scrub is characterized by mostly treeless (<2 trees/ha; FWC 2019), open expanses of low shrubs dominated by evergreen, or nearly evergreen, oaks Quercus spp. Infrequent but high-intensity wildfires and, more recently, prescribed burning and mechanical treatments (Rickey et al. 2007; Weekley et al. 2013) maintain Florida scrub in an early-successional state. Florida scrub in Ocala NF includes three species of scrub oaks: myrtle oak Quercus myrtifolia, Chapman’s oak Quercus chapmanii, and sand live oak Quercus geminata (Myers 1990). Most scrub at Ocala NF has been managed for commercial harvesting since the 1940s (Hinchee and Garcia 2017), creating a landscape of hundreds of clearcut stands of regenerating scrub embedded within a matrix of sand pine forest of various ages.

Within Ocala NF, scrub suitable for Florida scrub-jays occurs in three primary land management categories (Figure 1): sand pine forest (MA 8.2; 67,180 ha), established SJMAs (MA 8.4; 1,185 ha), and proposed SJMAs (current sand pine forest that has been proposed for future conversion to SJMAs (19,552 ha; USFS 2009). MA 8.2 is managed as sand pine forest for commercial harvesting; stands are clearcut at 35–55 y of age, roller chopped but not treated with fire, and often direct seeded with sand pine (Hinchee and Garcia 2017). Stands converted to SJMAs are burned with prescribed fire 6–12 mo after most, or all, of the trees are harvested and subsequently managed as early successional scrub in perpetuity (USFS 2009; Hinchee and Garcia 2017). Another 5,774 ha of scrub also occurs in the Juniper Prairie Wilderness Area (designated wilderness with no management), with additional scrub within the inaccessible Pinecastle Bombing Range.

Figure 1.

Sand pine forest and Scrub-Jay Management Areas (SJMAs), Ocala National Forest, Florida. Florida scrub-jay Aphelocoma coerulescens sampling locations in SJMAs are indicated with cross-hatching. We generated this map by using a geographic information system base layer created by the U.S. Forest Service in 2021.

Figure 1.

Sand pine forest and Scrub-Jay Management Areas (SJMAs), Ocala National Forest, Florida. Florida scrub-jay Aphelocoma coerulescens sampling locations in SJMAs are indicated with cross-hatching. We generated this map by using a geographic information system base layer created by the U.S. Forest Service in 2021.

Close modal

We studied Florida scrub-jays in three SJMA regions—Hughes East, Hughes West, and Southern West—during the breeding seasons (mid-March through early July) of 2016–2023 (Figure 1; Table 1). Within each of the three SJMA regions, we delineated a 97-ha focal study area with a 200- to 250-m buffer between it and adjacent landscape features (e.g., major roads) that might affect Florida scrub-jay occupancy, density, or productivity (Figure 1). Each of the focal areas was entirely scrub, with no wetlands or other plant communities. We added focal areas to the study incrementally (Table 1). The Southern West focal area started as 81 ha in 2021, with an expansion to 97 ha in 2022 (Table 1). The maximum area monitored was 291 ha (97 ha × 3 focal areas) in 2022, accounting for approximately 25% of the total SJMA acreage available in Ocala NF. We calculated stand age as the number of years elapsed since the last burning of the focal area (Table 1).

Table 1.

Number of Florida scrub-jay Aphelocoma coerulescens family groups in three focal areas within Scrub-Jay Management Areas, Ocala National Forest, Florida, 2016–2023. Stand age represents the number of years since prescribed fire in the focal area. We estimated Florida scrub-jay density as the number of family groups per hectare and per 41 ha (100 acres).

Number of Florida scrub-jay Aphelocoma coerulescens family groups in three focal areas within Scrub-Jay Management Areas, Ocala National Forest, Florida, 2016–2023. Stand age represents the number of years since prescribed fire in the focal area. We estimated Florida scrub-jay density as the number of family groups per hectare and per 41 ha (100 acres).
Number of Florida scrub-jay Aphelocoma coerulescens family groups in three focal areas within Scrub-Jay Management Areas, Ocala National Forest, Florida, 2016–2023. Stand age represents the number of years since prescribed fire in the focal area. We estimated Florida scrub-jay density as the number of family groups per hectare and per 41 ha (100 acres).

We studied the Florida scrub-jay population by using color banding, territory mapping, and a post-reproductive survey (Woolfenden and Fitzpatrick 1984; Fitzpatrick et al. 1991; Miller and Shea 2021; Cardas et al. 2023). These methods have been used successfully with Florida scrub-jays for decades to delineate the number of family groups per unit area (e.g., Woolfenden and Fitzpatrick 1984; Breininger et al. 1995, 2014b; Breininger and Carter 2003; Miller and Shea 2021), the primary metric of management interest for a cooperatively breeding species such as the Florida scrub-jay (USFWS 2007). Occupancy modeling and distance sampling are unreliable for this species (Miller and Shea 2021) because its behavior violates important assumptions of those methodologies (e.g., scrub-jays often approach observers and thus are usually not detected at their initial location; see Buckland et al. [1993]), nor do those approaches delineate the number and size of extended family groups.

We attempted to color band at least one adult Florida scrub-jay in each family group to facilitate differentiation of groups and territories during surveys. We trap tamed and captured scrub-jays by using walk-in Potter traps and drop traps baited with peanuts and mealworms and then banded them with a numbered federal aluminum band and a unique combination of three plastic color bands. All trapping and banding protocols followed established guidelines for the use of wild birds in research (Fair et al. 2023). By 2022, we color banded more than 50% of the adult population in our focal areas.

We made regular visits (usually one or two times per week) to each family group within the focal study areas during the peak breeding season (April–June). We recorded Florida scrub-jay territory locations in the field by using portable global positioning system units or aerial photos ranging from 1:2,400 to 1:13,000. We gave special attention to the locations of territorial encounters between neighboring family groups (Fitzpatrick et al. 1991) to delineate approximate territory boundaries (Bibby et al. 1992).

We used a midsummer post-reproductive survey as a standardized period for our annual benchmark of Florida scrub-jay density and productivity (Woolfenden and Fitzpatrick 1984; Fitzpatrick et al. 1991). We followed the methods of Fitzpatrick et al. (1991) and Miller et al. (2015) to conduct an intensive post-reproductive survey on all focal stands during 20 June–10 July each year (Miller and Shea 2021), when juveniles can be easily distinguished from adults by their plumage. Teams of paired observers played recordings of Florida scrub-jay territorial “weep” and “hiccup” calls (Woolfenden and Fitzpatrick 1996) for three, 1-min periods at survey points spaced 125–150 m apart on three or more separate mornings. We used territorial responses to delineate the number and size of family groups. We used paired observers to maximize the likelihood of maintaining visual contact with observed family groups and help avoid double counting. We provided training for all participants each year to ensure the accuracy of data collection (Miller 2015).

We also monitored family groups that occupied part of adjacent habitat patches, but not included in our annual count unless a clear majority of their territory was within the focal area. We calculated the number of family groups/41 ha (100 acres) to generate a standardized density estimate for each focal area each year. This standardized density estimate allows for comparison with stands of varying size receiving other management treatments (e.g., clearcut stands) at Ocala NF.

Data analysis

Building on models developed by Miller and Shea (2021), we used a single generalized linear model (Poisson regression with a log link function) to estimate how stand age (independent variable) influenced the density of Florida scrub-jay family groups in SJMA focal areas (dependent variable). The input data for this SJMA model are included in Data S1 (Supplemental Material). In the model, we included the linear and quadratic effects of stand age (i.e., age and age2) to account for the possibility that density peaks at an intermediate age. Our previous work found a monotonic linear relationship between area and Florida scrub-jay abundance in Ocala NF, and no evidence that other patch characteristics (e.g., edge or connectivity) influenced the abundance of Florida scrub-jays in Ocala NF clearcut stands (Miller and Shea 2021).

We fit the standard Poisson regression models in R v.4.2.1 (R Core Team 2022) by using the ‘glmmTMB’ package (Brooks et al. 2017). We assessed goodness of fit using a simulation-based approach to residual assessment implemented in the R package Dharma that tested for evidence of overdispersion and unexplained patterns in model residuals (Hartig 2022). We considered the support for the linear and squared stand age terms as significant if the 95% confidence interval for the respective parameter estimate excluded zero. For a negative quadratic effect, we would expect the linear term to be positive and the squared term to be negative.

For comparison, we also present family-group density data relative to stand age trends for Florida scrub-jays monitored on clearcut stands (of varying size) that Miller and Shea (2021) previously reported (2011–2014), combined with three additional years of data collected by the FWC (2015–2017). We include the input data for this clearcut model in Data S2 (Supplemental Material). We generated model predicted means and 95% confidence intervals by using a Poisson regression with a log link function identical to the function described above, except for the addition of a random effect term representing sampling year (Miller and Shea 2021). We used data and model results from clearcut stands with permission from the authors (Miller and Shea 2021). Complete R-code can be found in Text S1, Supplemental Material.

We estimated the density of Florida scrub-jay family groups in three SJMA focal areas for a total of 14 stand-years (2016–2023; Table 1). The density of family groups/41 ha (100 acres) ranged from 5.0 (Hughes East, 3 y postfire) to 12.9 (Hughes East, 7 y postfire; Table 1). We corroborated the high densities estimated during the post-reproductive population survey in Hughes East and West with demographic monitoring of color-banded birds throughout the breeding season. The dataset in Miller and Shea (2021) combined with three additional years of FWC data (see Methods) yielded a final dataset of 46 discrete clearcut stands studied for a total of 178 stand-years during 2011–2017 (Data S2).

Florida scrub-jay family-group density was consistently higher in SJMA focal areas than in clearcut stands (Figure 2). We observed a positive quadratic relationship between stand age and the density of Florida scrub-jay family groups in SJMA focal areas, similar to the trend observed in clearcut stands (Figure 2; Table 2; also Miller and Shea [2021]). Although Florida scrub-jay densities are similar in SJMAs and clearcut areas at young stand ages, the densities increased much more rapidly and peaked a few years later in SJMAs than in clearcuts (Figure 2). Based on model predictions, the maximum mean density of Florida scrub-jay family groups occurred at 8.5 y postfire (11.8 family groups/41 ha) in SJMAs and 6.2 y postharvest (5.5 family groups/41 ha) in clearcut stands.

Figure 2.

(Top) Observed mean densities (circles and triangles) and predicted densities (dashed and solid lines) of Florida scrub-jay Aphelocoma coerulescens family groups/41 ha (100 acres) as a function of stand age for clearcuts and Scrub-Jay Management Areas (SJMAs), respectively. We calculated stand age as the number of years since tree removal (for clearcut stands) or tree removal followed by prescribed fire (for SJMAs). We fitted Poisson regression models to data from 46 clearcut stands and 3 SJMA focal areas, during 2011–2023. Shaded regions represent 95% confidence intervals. (Bottom) Box plots showing median (solid horizontal lines), interquartile range (IQR; box), whiskers (±1.5 × IQR), and outlier values (greater than ±1.5 × IQR; solid black circles) of Florida scrub-jay family groups/41 ha (100 acres).

Figure 2.

(Top) Observed mean densities (circles and triangles) and predicted densities (dashed and solid lines) of Florida scrub-jay Aphelocoma coerulescens family groups/41 ha (100 acres) as a function of stand age for clearcuts and Scrub-Jay Management Areas (SJMAs), respectively. We calculated stand age as the number of years since tree removal (for clearcut stands) or tree removal followed by prescribed fire (for SJMAs). We fitted Poisson regression models to data from 46 clearcut stands and 3 SJMA focal areas, during 2011–2023. Shaded regions represent 95% confidence intervals. (Bottom) Box plots showing median (solid horizontal lines), interquartile range (IQR; box), whiskers (±1.5 × IQR), and outlier values (greater than ±1.5 × IQR; solid black circles) of Florida scrub-jay family groups/41 ha (100 acres).

Close modal
Table 2.

Parameter estimates, standard error (SE), and lower (LCL) and upper (UCL) 95% confidence limits from the Poisson regression models relating stand age to the density of Florida scrub-jay Aphelocoma coerulescens family groups in three Scrub-Jay Management Area (SJMA) focal areas (n = 14 stand-years) and 46 clearcut stands (n = 178 stand-years) in Ocala National Forest, Florida. We included stand area as an offset in the regression model, such that we express estimates as the expected number of family groups per hectare. All values are on the natural log scale, with the random effect (clearcut model only) expressed as a standard deviation. Model results from the clearcut stands were from the dataset in Miller and Shea 2021 (with permission).

Parameter estimates, standard error (SE), and lower (LCL) and upper (UCL) 95% confidence limits from the Poisson regression models relating stand age to the density of Florida scrub-jay Aphelocoma coerulescens family groups in three Scrub-Jay Management Area (SJMA) focal areas (n = 14 stand-years) and 46 clearcut stands (n = 178 stand-years) in Ocala National Forest, Florida. We included stand area as an offset in the regression model, such that we express estimates as the expected number of family groups per hectare. All values are on the natural log scale, with the random effect (clearcut model only) expressed as a standard deviation. Model results from the clearcut stands were from the dataset in Miller and Shea 2021 (with permission).
Parameter estimates, standard error (SE), and lower (LCL) and upper (UCL) 95% confidence limits from the Poisson regression models relating stand age to the density of Florida scrub-jay Aphelocoma coerulescens family groups in three Scrub-Jay Management Area (SJMA) focal areas (n = 14 stand-years) and 46 clearcut stands (n = 178 stand-years) in Ocala National Forest, Florida. We included stand area as an offset in the regression model, such that we express estimates as the expected number of family groups per hectare. All values are on the natural log scale, with the random effect (clearcut model only) expressed as a standard deviation. Model results from the clearcut stands were from the dataset in Miller and Shea 2021 (with permission).

At Ocala NF, sand pine scrub that was clearcut and then treated with prescribed fire (this study) supported consistently higher family-group densities than sand pine scrub that was clearcut and managed for ongoing pulpwood harvest (Miller and Shea 2021). It is not surprising that Florida scrub-jays were more abundant in burned areas than in clearcuts not exposed to fire. Empirical data from our study and previous research (Rickey et al. 2007; Weekley et al. 2013; Beatty 2019) indicate that early-successional conditions suitable for Florida scrub-jays persist for a longer period in scrub treated with fire than in scrub treated with mechanical clearing only. Over a range of pyrogenic plant communities in Florida, the ecological benefits of mechanical disturbance to wildlife are greatest when those treatments are combined with fire (Menges and Gordon 2010). Similarly, across a range of seasonally dry forest types in the National Fire and Fire Surrogate Study, many plants and animals responded more favorably to mechanical treatments when combined with fire than to mechanical treatments alone (McIver et al. 2012). The relationship between time since fire and arthropod prey in Florida scrub is not clear, but fire increases orthopterans in Florida dry prairie, another pyrogenic plant community in peninsular Florida (Larned et al. 2022).

The densities of Florida scrub-jays that we documented in SJMAs (≥9 family groups/41 ha in Hughes east at its peak habitat suitability; Table 1) are higher than the densities documented for conservation lands on the Lake Wales Ridge in southern Florida (typically 3.5–4 family groups/41 ha; Woolfenden and Fitzpatrick [1984, 1986]). However, precedents for high Florida scrub-jay densities exist elsewhere. Earlier work in Ocala NF clearcuts found that densities frequently exceeded 5–7 family groups/41 ha in suitable habitat (Miller and Shea 2021) and occasionally exceeded 15 family groups/41 ha at the ecotones of recently burned scrub where new territories are being established (Dudek and Miller 2021). Florida scrub-jay densities in remnant patches of scrub in a suburban–exurban landscape can reach 7–10 family groups/41 ha, especially when supplementary food is available (Lyon 2007; USFWS 2019b). Breininger (1992) measured densities in various disturbed plant communities at Kennedy Space Center on the Atlantic coast at 5–20 family groups/41 ha.

We note that implementation of the scrub restoration program is still in its early stages, and when SJMAs occupy a greater proportion of the landscape, scrub-jay occupancy and abundance patterns could change. In Atlantic coastal scrub, local Florida scrub-jay density can be influenced by habitat availability in the landscape matrix (Breininger et al. 1995; Breininger 1999). It is conceivable that as more SJMAs are established, there may be a lag time for the population to settle and grow in scrub patches of varying quality (e.g., Fretwell and Lucas 1970). Also, the average density of Florida scrub-jays in SJMAs might be lower in the future than what we observed during this study, depending on whether density regulation occurs (Newton 1998). Given that the amount of early-successional scrub in Ocala NF is now increasing (Hinchee and Garcia 2017), continued monitoring will be needed to assess whether scrub-jay family-group densities gradually level off in the future. A limitation of our study was its relatively short duration, and the effect of fire on Florida scrub-jay demography at Ocala NF will be better understood as more SJMAs mature. As more SJMA patches become available, future research could include testing for differences in fecundity among sites.

Scrub management activities at Ocala NF will need to be continually examined, especially the effects of fire management on habitat structure and Florida scrub-jay demographics (Breininger 2004). Research on the application of pyrodiversity, including mosaic burns, in this unique system seems essential to fine-tune management objectives (Menges 2007; FWC 2019). In sand pine scrub on the Atlantic coast of Florida, mechanical treatments before prescribed burning have helped managers apply fire safely and effectively (Roberts and Cox 2000; Schmalzer et al. 2003), but evidence is lacking that mechanical disturbance by itself mimics fire in this plant community.

This study provides the first quantitative data on the response of Florida scrub-jay populations to new forest management practices in this large and critically important population. Our results provide an essential component for developing accurate population models for Ocala NF under current conditions and for modeling the potential effects of future management decisions. With continued monitoring, researchers and managers can develop decision support tools (Conroy and Peterson 2013; Leston et al. 2020) to compare alternative management scenarios with respect to Florida scrub-jay recovery objectives at Ocala NF over longer time frames.

Please note: The Journal of Fish and Wildlife Management is not responsible for the content or functionality of any supplemental material. Queries should be directed to the corresponding author for the article.

Data S1. Summary of Florida scrub-jay Aphelocoma coerulescens family groups detected in Florida Scrub-Jay Management Area focal areas in Ocala National Forest (2016–2023). The estimate of density was the number of family groups/41 ha (100 acres).

Available: https://doi.org/10.3996/JFWM-24-022.S1 (431 Bytes CSV)

Data S2. Summary of Florida scrub-jay Aphelocoma coerulescens family groups detected in clearcut stands in Ocala National Forest (2011–2017). The estimate of density was the number of family groups/41 ha (100 acres). These data include Miller and Shea (2021) and three additional years of data from the Florida Fish and Wildlife Conservation Commission (2015–2017). Used with permission from the authors.

Available: https://doi.org/10.3996/JFWM-24-022.S2 (5.12 KB CSV)

Text S1. R-code for generalized linear model (Poisson regression with a log link function) to estimate how stand age influenced the density of Florida scrub-jay family groups in SJMA focal areas compared with clearcut stands Ocala National Forest (2016–2013). Data required to run code are saved as Supplemental Material Data S1 (for SJMA focal areas) and Data S2 (for clearcut stands). Code also generates Figure 2 plots.

Available: https://doi.org/10.3996/JFWM-24-022.S3 (62.4 KB PDF)

Reference S1. Breininger DR. 1992. Habitat model for the Florida Scrub Jay on John F. Kennedy Space Center. National Aeronautics and Space Administration, NASA Technical Memorandum 107543.

Available: https://doi.org/10.3996/JFWM-24-022.S4 (3.72 MB PDF)

Reference S2. Breininger DR. 2004. An adaptive approach to managing Florida scrub-jay habitat. Merritt Island, Florida: National Aeronautics and Space Administration. Technical Memorandum NASA/TM-2004-211532.

Available: https://doi.org/10.3996/JFWM-24-022.S5 (371 KB PDF)

Reference S3. [FWC] Florida Fish and Wildlife Conservation Commission. 2019. Scrub management guidelines for peninsular Florida. Tallahassee: FWC.

Available: https://doi.org/10.3996/JFWM-24-022.S6 (5.16 MB PDF)

Reference S4. [USFWS] U.S. Fish and Wildlife Service. 2006. Habitat Management Plan for Merritt Island National Wildlife Refuge. Titusville, Florida: USFWS.

Available: https://doi.org/10.3996/JFWM-24-022.S7 (13.2 MB PDF)

Reference S5. [USFWS] U.S. Fish and Wildlife Service. 2007. Florida scrub-jay (Aphelocoma coerulescens) 5-year review: summary and evaluation. Jacksonville, Florida: USFWS.

Available: https://doi.org/10.3996/JFWM-24-022.S8 (466 KB PDF)

Reference S6. [USFWS] U.S. Fish and Wildlife Service. 2019a. Draft revised recovery plan for the Florida scrub-jay (Aphelocoma coerulescens). Atlanta: USFWS.

Available: https://doi.org/10.3996/JFWM-24-022.S9 (338 KB PDF)

Reference S7. [USFWS] U.S. Fish and Wildlife Service. 2019b. Species status assessment: Florida scrub-jay (Aphelocoma coerulescens). Version 1.0. Jacksonville, Florida: USFWS.

Available: https://doi.org/10.3996/JFWM-24-022.S10 (16.7 MB PDF)

Reference S8. [USFS] U.S. Forest Service. 1999. National forests in Florida: land and resource management plan (Appendix E). Tallahassee, Florida: USFS.

Available: https://doi.org/10.3996/JFWM-24-022.S11 (234 KB PDF)

Reference S9. [USFS] U.S. Forest Service. 2009. Land and resource management plan amendment 8. Tallahassee, Florida: USFS.

Available: https://doi.org/10.3996/JFWM-24-022.S12 (345 KB PDF)

Funding for this project was from Florida’s Nongame Trust Fund, USFWS’s Section 6 program, and The Nature Conservancy. Foundational work on Florida scrub-jay populations at Ocala NF during the 2010s was made possible through cooperation and teamwork fostered by the FWC, USFS (especially Jay Garcia and Carrie Sekerak), and USFWS (especially Todd Mecklenborg). We thank the many skilled people who assisted with fieldwork, including Jessica Blain, Travis Blunden, Dustin Brewer, Alexis Cardas, Bobbi Carpenter, Anna Deyle, Sarah Dudek, Carolyn Enloe, Ben Ewing, Anna Fasoli, Craig Faulhaber, Adrienne Fitzwilliam, Simon Fitzwilliam, Jay Garcia, Zachery Holmes, Daniel Horton, Jamielee Hyatt, Marianne Korosy, Heather Levy, Philipp Maleko, Logan McDonald, Robert Mulligan, Hannah O’Malley, James Petersen, Lois Posey, Jess Rodriguez, Jacqui Sulek, Doug Sutherland, Mikayla Thistle, Kyle Titus, and Michelle Wilcox. Brittany Bankovich designed field maps. We thank our colleagues who provided helpful information or discussion during project development, including David Breininger, Craig Faulhaber, and Jay Garcia. Comments from David Breininger, Carolyn Enloe, Conor McGowan, Carrie Sekerak, and an anonymous reviewer improved earlier drafts. This work would not have been possible without the commitment of the USFS to scrub restoration at Ocala NF.

Any use of trade, product, website, or firm names in this publication is for descriptive purposes only and does not imply endorsement by the U.S. Government.

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Author notes

The findings and conclusions in this article are those of the author(s) and do not necessarily represent the views of the U.S. Fish and Wildlife Service.