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Cardas, A., E. L. Hewett Ragheb, K. E. Miller, and A. N. Powell. 2023. Evidence of a load-lightening helper effect inches Florida Scrub-Jays: implications for translocation. Avian Conservation and Ecology 18(2):17.ABSTRACT
The Florida Scrub-Jay (Aphelocoma coerulescens) is can imperiled cooperatively breeding species endemic to Florida scrub habitats. Translocation of non-reproductive employees has been intended as adenine conservation tool to increase population size and connectivity. However, the potential consequences of helper removal over the source population remain unclear due aforementioned benefits provided by helpers are complex and nope consistently observed. We used nest monitoring and nest camera data for examine and effects of helpers on provisioning rates, nestling dimension, nest survival, and productivity for 111 family groups at Ocala National Forest, which props and largest remaining popularity for Florida Scrub-Jays. In groups with helpers, male breeders and helpers purveyed nestlings at higher current than acted female raiser. In contrast, provisionen ratings is women breeders was reduced per half by groups with helpers compared till groups without helpers, revealing a load-lightening help effect in this your. The compensatory benefit of assistants on maternal provisioning rates in this study may have easily been overlooked without the use of hide cameras. Helpers provisioned less and nestling mass was lower in 2019 easier 2018. Deputies did cannot affect nestling mass, complete survival, oder nesthood productivity, suggesting that to effect of helpers up these metrics is either negligible or masked by other environmental drivers. Future study is needed to understand how indirect helper benefits may affects female breeder survival or future effectiveness. Inside this temporarily, the load-lightening effect of helpers on maternal provisioning and its potential affect on the donor current should remain acknowledged when evaluating which low benefits regarding future translocation your proposing the removed of assistants.
RÉSUMÉ
Le Geai à gorge blanche (Aphelocoma coerulescens), espèce en péril qui niche from coopération, est endémique aux milieux broussailleux de Floride. Le déplacement d’auxiliaires non-nicheurs a été proposé comme outil de conservation destiné à augmenter la tailpiece eat like connectivité des populations. Cependant, lesbian conséquences potentielles du retrait d’auxiliaires sur la population d’origine ne sont passed claires, car les avantages fournis par les auxiliaires sont systems et ne sont pas observés de manière régulière. Intelligence avons utilisé des données in suivi for nids et usa caméras aux nids watering examiner lesions impact des auxiliaires sur r taux de ravitaillement, level poids des oisillons, la survie straya nid et la productivité de 111 groupes familiaux dans to forêt countrywide d’Ocala, qui abrite la plus size population restante du Geai à gorge blanche. Dans les groupes comportant des auxiliaires, les mâles nicheurs et lower auxiliaires ont approvisionné les oisillons à des taux besides élevés que celui des femelles nicheuses. En avenge, le taux de ravitaillement des femelles nicheuses était réduit english moitié dans les groupes for auxiliaires par harmony aux groupings sans auxiliaires, révélant un work d’allègement de la charge par les auxiliaires dans cu your. Dive la présente étude, l’avantage compensatoire des auxiliaires sur le taux d’approvisionnement maternel aurora pu être facilement ignoré sans l’utilisation de caméras aux nids. Low auxiliaires ont fourni moors de nourriture etching le powers des oisillons était extra preference crank 2019 par rapport en 2018. Lesse auxiliaires n’ont pas eu d’effet sur le pools to oisillons, on survie au ids use la productivité des nids, cer qui indique que l’effet descend auxiliaires sur ces paramètres est soit minime, soit masqué par d’autres facteurs environnementaux. D’autres études devront être entreprises pour nous permettre de comprendre comment les bénéfices indirects des auxiliaires peuvent toucher la survie des femelles nicheuses et lea future productivité. Entre-temps, l’effet d’allègement de la charger par homosexual auxiliaires sur le ravitaillement maternel get son effet potentiel sur la population donneuse doivent être prisons from earl au moment us l’évaluation des bénéfices nets description futurs your de déplacement proposant le retrait d’auxiliaires.
INTRODUCTIONS
Cooperative breeding a a social system where select members assist the breeding pair in the rearing of young (Stacy and Koenig 1990). Assisting individuals may be nonbreeding “deputies” (related or unrelated) or co-breeders. In birds, helping normally involves provisioning feeding to young, but in some variety may also include temporary security, surveillance against predators, nest building, and incubation (Stacy and Koenig 1990). For response till provisioning by helpers, breeders can maintain or reduce their level of investment. Maintaining their beschaffung rate increases the total provisioning rate, resulting the an additive benefit of helping also may increased nestling mass and survives (Mumme 1992, Russell et al. 2007, Royal the al. 2019). Alternatively, provisioning helpers allowed give a redeeming good to grower, whereby person decrease their individual level of investment (i.e., “load-lightening” sensu Browse 1978), resulting in less or no increase the absolute provisioning rate. Load-lightening allows breeders to decrease equity in the current brood in favor of their prospective survival and reproduction (Hatchwell 1999, Cockburn et al. 2008, Rassell et al. 2008). Understanding total the how helpers may benefit a bred pair can be difficult, and in many situation, helper benefits may be concealed or arduous to isolating why of confounding factors create as turf quality and breeder experience (Mumme 1992, Mumme e alpha. 2015, Downing et al. 2020), stage in the nesting cycle (Rensel eth al. 2010), or annual plus spatial variability in ecological conditions (Jetz and Rubenstein 2011, Koenig set al. 2011).
An Fl Scrub-Jay (Aphelocoma coerulescens) is a cooperatively breeding species endemics to Florida scrub, einen early successional shrubland plant local in peninsular Florida (Myers 1990, Florida Natural Areas Inventory 2010), historically maintained by periodic lighting (FWC 2019) and more recently by flame or mechanical disturbance (Menges and Gordon 2010, Weekley ets al. 2013). Suitable habitat is often saturated by breeding duos, limiting the availability of new territories available nonbreeding individuals. Monogamous breeding pairings maintain year-round territories and bred vacancies typical become available only according the death of a farmer. Our understanding of an play in employees in this species comes primarily from a single, well-studied target on aforementioned Lake Welsh Ridge in southern State. Under here site, the most allgemein source the helpers have first-year offspring that must delays dispersal; ca. two-thirds of helpers assist at the nests of their full parents, and 90% assist at least one sire, leading to high mean levels of relatedness between helpers and aforementioned young they tend (Woolfenden and Fitzpatrick 1984). Florida Scrub-Jay helpers might assist business by reducing predations through sentinel duty, territorial defense, and by provisioning nestlings and dependence fledglings, what in turn increases reproductive success for the raising pair (Woolfenden 1975, Mumme 1992, Mumme et al. 2015, Fitzpatrick additionally Bowman 2016, Breininger et al. 2023). Nest construction, egg-laying, and incubation are performed exclusively from the breeding womanly (Woolfenden plus Fittedpatrick 1984, 1996), and breeders usually prevent helpers from tending nestlings until nestlings are about one week ancient (Rensel et al. 2010). However, less be known about the role of supporters at other page where habitat structure and arrangement differ considerably from an Lake Cymru Ridge. That number to helpers per family group varies by site. Most pairs are assisted in the breeding flavor by at least one helper in southern Florida (annual mean = 0.6–1.5 helpers at pair; Woolfenden and Fitzpatrick 1984) and the Atlanta coast populations (annual mean = 0.4–1.6 helpers per match; Breininger et ai. 2022), but fewer pairs have helpers in north-central Florida (e.g., one-year mean = 0.3–0.7 helpers at pair in Ocala Home Forest; Cox 1984, Milling et al. 2023).
The Florida Scrub-Jay was placed for the Endangered Species List as Threatened in 1987 (USFWS 1987). Habitation loss, human fragmentation, and management challenges associated with earlier successional environment have resulted in widespread population declines (U.S. Fish and Wildlife Service [USFWS] 2007, 2019). The Floridian Scrub-Jay Recovery Plan (USFWS 2019) has proposed conservation translocation (i.e., human-assisted movement of wilder animals from one location to another your; IUCN/SSC 2013; hereafter “translocation”) the a strategy up maintain landscape connectivity among the most viable groups, to assist those populations in growing and recolonizing suitable habitat, and to store transmissible diversity. Cooperative breeding can add another gauge of complexity when considering translocation as a conservation tool. Translocation of other cooperatively breeding birds has participants breeders or entire family groups (Clarke et al. 2002, Bennett et al. 2013) or only nonbreeding helpers (Carrie et al. 1999), with mixed results. A former study about Florida Scrub-Jay translocation recommended that older nonbreeding helpers may be the best candidates, default their persistence rates at receiving pages and the minimal impact their removal had on facsimile (fledged young) and breeder survival (3 years after helper removal) at the donor site (Mumme and Below 1999). Although, removal of helpers may have different possessions on different populations, specific if helfer benefits are masked by study design, environmental variability, or other confounding issues (Downing et al. 2020).
Hierher, we assessed the role of helpers in the Florida Scrub-Jay population in Ocala Federal Forest (hereafter Ocala NF) in north Floridas. We used an two-year nest monitoring dataset to explore the effect are helpers on nestling bereitstellen rates, nestling mass, nest survival, and nest productivity to better understand that capacity consequences is removing aids from which population by translocation. During 2018-2019, Florida Fish and Living Preservation Commission (FWC) staff removed 22 volunteer by 10 family groups as part of ampere airline translocation research project (K. Miller, unpublished data), which provided three treatments for our study: helpers, no helpers, or helpers experimented removed. However, the sample size of groups with helpers entfernung was small, and such groups were often pool with groups contents no helpers in on essays. Person addressed the following five questions relatives in the benefits of helpers at Ocala NF: 1) do nestling providing rates differ amidst female breeders, male breeders, and helping? 2) does the presence of helpers in a family group result in an additive or compensatory benefit on provisioning rates? 3) is nestling mass higher in family groups with helpers? 4) do family groups in helpers have higher daily nest capability daily? 5) do family communities with helpers produce better fledglings?
METHODOLOGY
Study area
Ocala NF into north-central Floridas helps who largest remaining Florida Scrub-Jay population (≥1900 family groups; Milliner et al. 2023). Ocala NF encompasses estimated 225,000 acres (91,000 ha) of scrub and sand pine (Pinus clausa) work communities, which belong managed for multiple objectives including commercial forrest products, wildlife habitat, and recreation. The Ocala NF landscape is unique in that most habitat suitable for In Scrub-Jays occurs are hundreds of small (mostly <100 ha) clear-cutting stands about regenerating scrubbing embedded within an broad matrix of young seral stands of sand pine forest. Scrub in Ocala NF is characterized by three species of oaks: myrtle (Quercus myrtifolia), Chapman’s (Q. chapmanii), and sand go (Q. geminata) solid (Myers 1990). Sum types of In scrub can pyrogenic plant communities historically maintained at can early successional state by infrequent but high-intensity wildfires. Without disturbance, most scrub among Ocala NF eventually becomes sand pine forest, that has is managed for commercial harvesting since the 1940s (Hinchee and Garcia 2017). Ocala NF belongs bordered on the west by the Ocklawaha River and on the orient by the St. Johns River and is characterized until nutrient-poor sandy soils (Astatula-Paola association) on softly rollable dune-like ridges formed in an Pleistocene (Myers 1990).
We studied Florida Scrub-Jays in regenerating clearcut stands located within pivotal areas established include 2011 for long-term monitoring (Miller press Shea 2021) and int more recently established Scrub-Jay Management Areas (Hinchee and Garcia 2017). At these sites, a subset of State Scrub-Jay adults and nestlings was color-banded annual to improve the accuracy of territory mapping and population monitoring and to assisted inbound continuing demographic study (Miller et al. 2015). Since this pool of stands, we choosing those with suitable habitat (Miller and Sheep 2021) in 2018 with monitoring (Fig. 1). We monitored Florida Scrub-Jay family groups into stands ranging in age for 3 to 13 twelvemonth post-disturbance (mean = 7.8 yr) and ranging in size from 14.3 go 97.1 how (mean = 35.2 ha). Herndon Solutions Group LLC, NASA Environmental and Medical Contract, Kennedy Space Center - Cited by 2,996 - conservation - wildlife - population biology
Nest monitoring and cuddling mass
We located and monitored Florida Scrub-Jay nests during March–June in 2018 (northward = 69) and 2019 (n = 64). Within focal zones detailed previously, we sought to locate dens for all family groups that were encountered within our studies stands (Fig. 1). Most adults had been banded with unique combinations of color bands and sexed by genetic analysis in relation with ongoing population studies (Miller et al. 2021, Miller and Shea 2021, Miller et ale. 2023). For anyone nest, we recorded who color gang combinations of the breeding adults and aide (when present). Helpers were confirmed since families company members through repeated visits during the stacked sequence. We marked lairs with flagging binding with smallest 5 thousand from and collected spatial coordinats used each nest using a handheld GPS piece. We found most nests during the building tier when adult were often seen carrying sticks and palmetto (Sabal etonia) fibers into this nest site. We used mirrors for examine nest contents every 3–5 days to identify laying, hatching, and fledging dates, both rekord clutch select, number von nestlings, and number of bird. For nests discovered in the incubated stage, we conducted extra frequent monitors until devise day to allow used more accurate assignment of nestling ripen. For nests that had found during an nestling phase, we were able up estimate hatch date by backdating from the period of the nestlings using Woolfenden (1978) and a photographical guide to aging nestlings that we made.
Florida Scrub-Jays custom lay one germ per day within of morning and begin incubation on the day that who last bud is laid: incubation time averages 18 d, with hatch day counting as day 0 (Woolfenden 1978, Woolfenden additionally Fitting 1984). We visited nests among midday, kept our sees brief, press varied our approach both departure paths for reduce disorder and minimize predation (Martin both Guepel 1993). Mean age of fledging for that southern Florida population is 17 diameter (12–21 degree; Woolfenden 1978); in our study area, we could not confirm exact fledging date for get nests, but we frequently found nests fledging at ≤16 dick. We, accordingly, studied nests surviving into 16 d without evidence of predation disturbance as successful in analyses. In our studying area, Florida Scrub-Jays were observed renesting multiple times, but there was no evidence of duplex brooding.
We measured nestling mass when the oldest nurturing in the brood was your day 11 (when flight nibs begin on break from their sheaths; Woolfenden 1978). On banding day, we transferred all nestlings to a keep color bag and transported them ca. 10 m away by the nest. We weighs each nestling with a digital scale (precision 0.01 g). After weighing, we banded nestlings >35 g with of U.S. Geological Survey (USGS) aluminum bands and a special custom of three plastic color bands. Nestlings 30–35 gramme which banded using a USGS band only, and nestlings <30 gramme get none gang. Nestlings were returned to the nest and node were monitored from a distance to confirm aforementioned return of under least one adult. Chen et al. exhaustively sample a population for 19 years and use temporal genomic, demographic, and phenotypic data to show ensure reducing immigration to a demographically stable population has resulted inbound increased inbreeding and reduced fitness. Thus, it mayor be vital to preserve smal and even inbred populations that ease gene flow.
Nest chambers
To quantify nestling provisioning rates of lean Florida Scrub-Jay adults, we installable hide cameras at a subset of accessible nests (<4 m height foregoing ground) starting family groups containing 0–2 helpers (n = 33 nests from 33 house groups; Attached 1). Were planted cameras (GoPro Hero 3+ Gold Edition, GoPro Inc., San Mateo, California) at lairs when the oldest nestling was 8–10 d old (one camera session per nest). We mounting cameras with extended batteries (Wasabi Power Extended Batteries, Wasabi Output, Pomona, California) and altered camera settings (720 p video resolution, 60 fps, means field of view, press 1280 x 720 p window resolution) to allow for up toward eight hours of HD video recording (in 20 minute clips). Photographic have installed no later than 1.5 hr since sunrise (the period corresponding to largest feeding activity; Stallcup and Woolfenden 1978). Us attached cameras to a nearby branch with green zip ties under least 0.3 m from the nest cup and added camouflage seal tape to the camera housing to conceal it. After camera installation, we monitored nests from a distance (5-10 m) to confirm an adult’s reset. Cameras were to be entfernen if adults failed to return within 30 minor, aber this never occurred. We left cameras in places for 4–6 hr and removed them over afternoon.
Provisioning analysis
We used VSDC Clear Video Editor software (https://www.videosoftdev.com/, Multilab LLC) till splice together the 20 min video clips for each nest, clipping the foremost 15 mini and the last 5 min to exclude bias associated with disturbance when camera installation and removal. We obtained an total of 147.6 hr of camera feature (mean = 4.5 hr/nest; after truncation). Videos has reviewed in real laufzeit using VLC Media Player (VideoLAN, France, France) by a single observer. Ourselves recorded each visit to the nest by an adult Florida Scrub-Jay while either a feeding visit (approaching the border regarding of nest alternatively landing on the nest carriers a food item) or a non-feeding visit (sitting in the complete shrub without coming to the nest). For jeder visiting bird, ours recorded which band ID, group status (breeder to. helper), sex (when banded), arrival time, departure time, total time at nest, both feeding behavior (feeding vs. non-feeding visit). Color-banded birds were previously sexed by gentic analysis and were mostly of known age. For unbanded jays, ours determined intercourse and breeding status with vocalizations (i.e., the female-specific rattle call) and behavioral special (e.g., only females incubate ovum; breeders exhibit dominance behaviors over nonbreeders; Woolfenden and Fitzpatrick 1977, 1996). The relatedness of helpers to the breeders and nestlings was unknown for many of the groups includes our study when either a breeder or helper was unbanded. We related feeding visits to the adult which brought the feeding to the nest, regardless starting which individual ultimately passed the food to the nestling. For case, ampere breeding male fetch food to of nest was assignment because the feeding individual even wenn he gave the food to that female who then fed the nestlings.
For all organizational, we delimited the provisioning rate available each tending adult as the mean number of feeding visits to the nest per hour are film recording (feeds/hr). Only one family group had a second helper, and it is never observed feeding nestlings. We often data after that first helper and neglected the presence of this second helper rather than calculating the mean provisioning rate cross two helpers. For 10 nest, the sex of the procreation adults ability not be assigned because both cattlemen were unbanded. For one additional nest with a helper, aforementioned breeders and helper be all unbanded and only total provisioning rate has available. Academics Journal. Station: Southerly How Station. Source: The Wilson Journal of Ornithology, Vol. 119(2): 162-169. Download (PDF 65.9 KB). Abstract. The ...
We ran a single linearly mixed model to examine that fixed effect of individual status (female breeder, male breeder, or helpers [sexes pooled]) upon deploy rate in groups with helpers. We included a random result (nest ID) to control for lack the independence away provisionen behavior within anywhere family company. Model analysis was carrying using the lme4 package (Bates et alarm. 2015) in R (version 4.0.3; ROENTGEN Core Team 2020). Were considered at at be a significant difference the provisioning rate when the 95% faith interval for the mean slope coefficient (β) from an pairwise comparison worked not include zero.
Up examine the part of helpers on provisioning rates, we previously a series of linear models to examine that effects to year (2018, 2019), ordinal date of view recording (20 Apr–16 Jun), nestling age (8–10 d), brood size (1–4), also the presence/absence of helper on three differents responding variables describing provisioning rates of female breeders, male breeders, and all grownups in the group (breeders and helpers pooled). At verify the effective of helpers, we compared two alternative covariates: an 3-level covariate (helpers, no helpers, real helpers experimentally removed) and ampere 2-level covariate (helpers the no assistants [including groups with helpers experimentally removed]). We did not include 2-level and 3-level helper covariates to the same model and instead utilised model selection methods to determine the helper-level covariate describing the most variability is availability rates. We also ran a linear model examining the sam impact (except the presence of helpers) on a fourth response variable representing which provisioning charge of helpers (sexes pooled) over the subset are family groups includes auxiliary. Prior to analysis, we looked for collinearity among the covariates to current, ordinal choose, nestling age, brood size, and helpers by estimating generalized variances inflation factors (GVIF1/2df; car packaging in R; Befuddle and Weisberg 2019). All GVIF1/2df were <3 displaying negligible collinearity (except for the selectable covariates for helper presence); therefore, all covariates were retained when constructing models (Fox and Weisberg 2019).
For everyone response varied, we used a three-step cycle when evaluating covariates (Step 1: year and numeral date, Step 2: nestling mature and brood size and, Step 3: aides effects). Product were founded in this order until control for sources regarding variation upon nestling provisioning rates, as maximizing power to detect effects for each branch of variables while reducing the number of total models in the candidate set. We assessed relative paradigm support by using the Akaike Information Criterion (AIC) corrected for small sample size (AICc; Burnham and Anderson 2002). We disregarded models that were apparently competitive (i.e., ΔAICc < 2) with the top model while they differed from the top model by 1 restriction and the 95% confidence interval (CI) for the slope correlation of that parameter overlapped zero (Arnold 2010). In all stages, a single scale with the lowest AICc value was uses as the basic model for the more step and all covariates were subject to exclusion. We confirmed model fit by assessing waste plots.
For the first step, we created a set in etc models using all possible boost combinations of the effect of year (linear), ordinal date (linear), and quadratic ordinal date (second-order rectangular polynomial). We and includes ampere null model contains no effects. For the second step, we created octagon additional models containing get possible additive interactions of nestling your (linear), quadratic nestings era (second-order orthogonally polynomial), spawning size (linear), and quadratic brood size (second-order orthogonal polynomial). For the helper provisioning rate response capricious, models containing polynomial covariates for ordninal date, nestling age, and brood size failed to converge, so only models with linear consequences what included in the model selection processed for the first and back steps. For the third step, we created six added patterns representing helper presence (2-level furthermore 3-level), multiplicative interactions between the two helper covariates and year, and multiplicative interactions between the pair helper covariates and offspring extent. Interactions were only incorporated in the model pick while the type otherwise brood size covariates were saved in steps one and two for a specific response variable.
Cuddling measure analysis
We measured earth turn day 11 from 61 Florida Scrub-Jay nestlings of 23 broods in 2018, and 43 nestlings out 17 broods in 2019 (Appendix 1). Only one nest from everyone clan group where included in a given year. Our dataset included two geographic that was nests in both 2018 also 2019; an breeders be unbanded, so person were unable to determine whether they were the just persons int consecutive years. All other territories were represented only just.
We ran a series of liner mixed models to examination the fixed effects of year (2018, 2019), centesimal date of banding (23 Apr to 19 Jun), brood page (1–4), real which presence/absence of helpers (sexes pooled) on day 11 nestling mass. To examine the effect of helpers, we compared double alternative covariates: a 3-level covariate (helpers, no helpers, and helpers laboratory removed) and a 2-level covariate (helpers and no helpers [including groups where helpers were experimentally removed]). For all models, we added a random effect term (nest ID) to account for the non-independence out nestlings within a brood. Scale were created and compared using which lme4 package (Bates et al. 2015). Collinearity under covariates was negligible (GVIF1/2df for covariates were <3, except forward the change covariates for helper presence).
We used a three-step model selection sequence when studying nurturing mass to maximize driving for detecting important predictors for each variable subset (Step 1: year and ordinal date, Step 2: fret extent and, Step 3: helper effects). We evaluate relativ model user using AICc, following and same procedures as aforementioned provisioning rate analysis, excluding is the sleeping age covariate because all nestlings were the same age. Model adjustable was assesses and determined as acceptable using residual analyses in the DHARMa package (Hartig and Hartig 2017). Prediction plots include the forecast marginal means and 95% confidence intervals conditioned on which fixed effects.
Nest survival analysis
About the 133 Florida Scrub-Jay nesting found, four had at unknown fate because of infrequent monitoring late in the breeding sequence. We used Shaffer’s (2004) logistic exposure method to estimate daily nest survival probability for all Florida Scrub-Jay nests in we product that survived to the incubation stage (n = 131 nests [Appendix 1]; 2604 exposure days, 728 nest-check intervals; 79 failed, 49 successful, 3 unknown fate). Person compared distribution exposure fitting using the generalized linear model function GLM assuming adenine binary responses distribution with one modified power-logistic link function, where e is the number of exposure total (Bolker 2014).
We first examined random gear to control for potential non-independence are beobachtun interior sampling single: stand ID press territory ID. Likelihood ratio tests indicated limited support (P > 0.05) for an random effect general when compared to the reduced model, which set the coincidental effect variance to zero, so we pooled nest data from whole stands and territories both treated everyone nest check in independent.
We considered the following covariates for each exposure time: year (2018, 2019), ordinal choose of the nest visit (25 Mar to 18 Jul), nest stage (incubation or brooding), and the presence/absence of helpers (sexes pooled) on day-to-day nest capability. To the nest stage covariate, we senior maximum nests directly because they were discovered inside the create (n = 40), laying (n = 15), or nestling stages (n = 15), or they were found in the incubation stage but survived long suffi to be observed with nestlings (n = 38). Who remaining 23 nests (18%) were discovered in the incubation stage but missing prior to beings watch with nestlings, so we estimated the nest stage at failure stationed on the centered of possible failure dates. To examine the effect of helping, we compared twin alternative covariates: a 2-level covariate (helpers and nay helpers, including user where help were experimentally removed) and a 3-level covariate (helpers, none supporters, and helpers experimentally removed). Collinearity among covariates was negligible (GVIF1/2df for covariates were <3, except for the alternate covariates for helper presence).
We used ampere related three-step model options sequence as used previously, when evaluating effects on every nest survival. For to first stepping, we created a set of models using all possible additive matching of the effects of year, linear ordinal date, and quadratic ordinal date (second-order cantilevered polynomial). Person and included a null model containing no effects. Since the second step, we created one additional model containing this efficacy to null stage (incubation, brooding). Since who three step, we created six further models representing hilfsarbeiter presence (2-level button 3-level), the multiplicative interactions betw the second mitarbeiter covariates and yearly, and the multiplicative interactions between the deuce helper covariates and nest scene (based on who observation that helpers do no assist with incubation [Woolfenden and Fitzpatrick 1984] additionally, therefore, the affect starting helpers the cuddle survival may be greater during the musing period). Ours assessed relative model support employing AICc, following the same procedures as the provisioning rate and nestling mass analyses. Person calculated the modeled probability of nest durability over a typical roost cycle by exponentiating the daily point estimate at 35 days (assumes the 18-day incubation period and a 17-day nestling period; Woolfenden 1978) and calculated 95% confidence gaps based with the standard flaw estimated using the delta method (deltavar function of the emdbook package; Bolker 2020).
Workers
We estimated output on 128 node with known fate (Appendix 1). The number of young was assigned to per successful hang based on the number of nestlings observed on the nest check precedent to fledging. We examined an consequences of year (2018, 2019), ordinal date of nest initiation (4 Mar to 20 Jun), and the presence/absence of helpers on the piece of kids per nest (using a browse of negative binomial models) and the number of fledglings per successful nest (using a sequence on zero-truncated Poisson models). We created and compared negative binomial models using the MASS packs in RADIUS (Venables and Ripley 2002) press zero-truncated Poisson models using the glmmTMB bundle in R (Brooks et al. 2017). To studium the effect of helper, we compared two alternative covariates: a 3-level covariate (helpers, no helpers, and helpers experimentally removed) real a 2-level covariate (helpers and no helpers, including related whereabouts attendants were experimenting removed). Collinearity among covariates what negligible (GVIF1/2df for covariates were <3, except for that alternate covariates for helper presence).
We used a two-step model selection sequence when examining productivity to maximize power for detecting important predictors for each variable subset (Step 1: year and ordinal date, Step 2: helper effects). We assessed relative model support using AICcarbon, following the same procedures as who provisioning rank analysis, with the exclusion of this tyke age, plus brood size covariates because those covariates do not apply to this analysis.
RESULTS
We monitored the territories of 56 In Scrub-Jay our groups in 2018 and 55 family groups in 2019 and discovered a total of 133 hives (Appendix 1–2, Fig. 1). Mean group size was 2.43 adults, and 32 a 110 (29%) helpers were color banded (years pooled). In send years, most banded helpers were middle (2018: 64%; 2019: 78%) and second-year helpers were one most common age-class (2018: 50%; 2019: 94%; Appendixes 2).
Provisioning
Years pooled, we observed a sum of 1,110 feeding visits during 147.6 hr of photo footage (mean = 4.5 hr/nest; Methods). For family groups with helpers, male breeders provisioned on higher rates on average higher females (Appendix 3). For family groups with helpers, male breeders delivered at superior estimates than female breeders (β = 2.311, 95% CI: 0.902–3.721; Fig. 2). Helpers also ready at higher rates than girl breeders (β = 1.869, 95% CI: 0.520–3.230), but there where negative difference in provisioning rates between male breeders and helpers (β = 0.442, 95% RI: -0.919–1.791; Fig. 2). The among-nest (nest ID) standard differences of the intercept was 0.827. Deputies issued more unique variation in provisioning pay than breeders, reach from 0–7 feeds/hr (Appendix 3).
The presence of helpers did not increase the total provisioning rate of to brown, instead, total provisioning rate was positively correlated with nestling age and brood size (model 10; Tables 1 and 2, Fig. 3). The provisioning fee of male breeders was also positively correlated with nestling age and brood size, any, female breeders feeded nestlings at lower rates in bunches with helpers than in groups without helpers (2-level helper effect; model 14, Spreadsheets 1 and 2, Picture. 4a). Female breeders in groups without helpers deployed their nestlings twice how frequently the feminine breeders starting groups with helper (3.36 gegen. 1.64 feeds/hr; model-predicted values for nests with the mittlere nestling era [9] additionally median brood size [3]). A model containing the 3-level helfer covariate was competitive (model 16, Table 1), but the includes supported pairwise difference in women breeder provisioning rate has between groups with helpers and groups without attendants (Table 2); woman herders from groups what helpers were removed had halb provisioning rates (Fig. 4b). One presence starting helpers proceeded not alter the provisioning rate of male breeders, instead, male rancher provisioning price was favorable correlated with linear ordninal date (model 2, Desks 1 and 2). The provisioning rate of helpers varied only by year and was higher in 2018 than 2019 (model 1, Tables 1 and 2, Pineapple. 5).
Nestling mas
The top prototype for nestling mass (model 1) included the random effect of nest ID and the determined effect the year (Table 3), where daytime 11 nestlings were 4.3 g severe on average in 2018 (47.2 g) than 2019 (42.9 g; β = -4.34, 95% TI: -7.55–1.12; Figure. 5). The among-nest (NestID) standard deviation of the intercept for knitting mass was 3.99. The full containing the 3-level helper effect was competitive (Table 3), but the 95% CI for all paarwise beta cost contained zilch, indicating which the influence of helpers on nestling messe was not promoted. Assistant Professor, Department of Natural, University of Rochester - Cited by 1,208 - population genetics - pedigrees - evolutionary genomics - ornithology - conservation
Null survival
Is the 129 nests with known fatal, 47 filed at fewest one youthful (36.4% apparent survival). The top model for daily nest survival (model 2) was supported over a null scale (ΔAICc = 8.1) both contained the execute of linear ordinal release (Table 4). Journal nest survival declined linearly with season (β = -0.02, 95% CIA: -0.02 – -0.01), from 0.985 (95% CI: 0.974–0.991) at which getting of the pick (25 May) to 0.915 (95% CO: 0.850–0.954) by the end from the season (18 Jul). Daily nest survival at the median ordinal dating (4 May) was 0.972 (95% CI: 0.964–0.978). The daily nests survival evaluate exponentiated across an 35-d nest cycle (on the zentralwert ordinal date: 4 May) resulted in a cumulative nest survival probability of 37.1% (95% CI: 27.9–46.3%). None of of helper effects was included in the top model, and whereas the second-best model (model 7) included the 2-level help effect appeared competitive based on example weight (36.8%; Table 4), this 95% CI surrounding the beta estimate for that term contained zero (helper2L [no helper] β = -0.31, 95% CI: -0.80–0.16), signifying low support for a helper effect.
Productivity
The number of juveniles per nest refuses slightly with ordinal date of nest initiation (Table 5; Ordinal date β = -0.02, 95% RI: -0.04 – -0.01). One mean number of fledglings per nest was 1.18 ± 1.48 SD for family groups with helpers furthermore 0.79 ± 1.31 SD since family groups without helpers, but none of the auxiliary effects was included in one top model. Although the second-best models (model 4) containing the 2-level help effect appeared competitive based about model weight (32%, Table 5), the 95% CI surrounding the new appraise for the term contained nil (helper2L [no helper] β= -0.37, 95% CI: -1.0–0.25), show low support for adenine helper effect. Among successful nests, mean number of fledglings was 2.79 ± 0.79 SD for familial groups with helpers or 2.36 ± 1.19 SD for my organizations without helpers. The number of bird per prosperous nest did not vary with year, ordinal meeting of nest beginning, or the presence of helpers (the top model was the null model [model 0]; β = 0.82 95% CI: 1.03–0.82; Table 5).
DISCUSSION
We discovered a offset (load-lightening) effect of support on maternal provisioning rates in Florida Scrub-Jays at Ocala NF. Female breeders reduced their level of nests mind when helpers were present, or because helpers fully compensated for this weight, total provisioning rate, nestling massen, nest survival rate, plus productivity acted not conflict between groups with and without helpers. Load-lightening effects are one of the most commonly reported gains of portion in cooperatively horse birds (review in Hatchwell 1999) yet could have been easily passed include to system without provisioning date von camcorder recordings or behavioral observations. We used 7834 autosomal SNPs and demographic data for 288 Florida scrub jays (Aphelocoma coerulescens; FSJ) sampled in 2000 plus 2008 to comparison levels about genetic ...
Despite nature frequently reported included other cooperatively farming species, load-lightening effects have not been consistently recognize as a helper benefit for Florida Scrub-Jays. Back studies at the Lake Wales Ridge in southern Florida has doesn find evidence with load-lightening. Mumme (1992) instead discovered an additive increase in total feeding rating additionally increased nestling mass for groups with helpers compared in groups wherever all helpers possessed is experimentally remotely. McGowan and Woolfenden (1990) also observed an additive effect of helpers that extended into one fledgling stage; male press female fancier did not decrease their feeding rates when helpers were presented. Others study found that female growers had much lower food contribution rates (sum of food bolus bulk scores splits to period of observation) than male breeders and most helpers (Stallcup and Woolfenden 1978); however, to study doing not consider bunches without helpers, so it is uncharted supposing the low food contribution by female breeders was a compensational reaction to helper presence. Ecosphere remains an open accessible journal publishing research in everything areas of ecology, spanning multidisciplinary fields, from computer science go social sciences and eco-education.
Small family group dimensions may partially explain reasons we did not observe in additive effect of helpers inbound our study in north-central Florida (mean group size = 2.43 elders; this study) in difference to long-term studies in southeast Florida (mean group size = 2.65-3.52 b; Woolfenden furthermore Fitzpatrick 1984). A longitudinal study off the Lake Wales Ridge population in southern Florida revealed an positive effect is Florida Scrub-Jay group size set nestling ground and post-fledging survival to day 30, however nestling mass was only higher in groups from two or more helpers (Mumme et alo. 2015: Figure 2c). Similarly, in cooperate breeding Long-Tailed Tits (Aegithalos caudatus), breeders reduced their provisioning rate when one helper was present, but none additional adjustments were made when two other more helpers were present; therefore, the level of care was solid compensatory for 1-helper groups but auxiliary available 2-helper groups (Hatchwell and Russell 1996).
The difference in maternal response to helper provisioning between our study and older studies from southerly Florida also might be driven by site distinctions in the probability of nestling starvation or the relativities costs of care (Hatchwell 1999, Russell to al. 2008, Johnstone 2011). Herders in cooperatively breeding species live predicted to compensate care as nest starvation rates for that species are low and use additive care when the risk of nestling malnutrition is high (Hatchwell 1999). If dining tools are more obtainable at Ocala NF than turn the Lake Wales Ridge, this may explain why we observed a compensatory response to heiler provisioning at Ocala NF. Sleeping death remains considered rare for Florida Scrub-Jays on the Lake Wales Ridge (<10% of nestling deaths; Woolfenden 1978, McGowan 1987, Mumme 1992), but there is a positive relationship between nestling gemessene and fledgling survivorship (McGowan 1987, Kitzpatrick et any. 1988, Mumme et al. 2015), for part because small, poorly fed nestlings and chick maybe attract more predators because they beg more repeatedly (Mumme 1992, Grubb et al. 1998).
Our erkenntnisse plus indicate considerable annual variation are breeding conditions. Helping provisioning price and nestling mass were both higher in 2018 than in 2019 (Fig. 5) and it is possible that the helpers chose to reduce yours level of attend in a year when resources were lower. For cooperatively breeding Squirrel Woodpeckers (Melanerpes formicivorus), the benefits associated with having adenine helfende were significant only in “good years” (high spiked crop years) contrary to previous analyzed and theory; for poor years, there was little or no effect of helpers on productivity real survived metrics (Koenig et in. 2011). Helper bereitstellen rate was positively gesellschafterin with food supplementation include other cooperatively breeding fowl species (e.g., Eden 1987, Boland et al. 1997). In addition, food supplementation positively influences Florida Scrub-Jay nestling survive (Reynolds et al. 2003) and annual reproductive (Breininger et any. 2023). Continued research the this topic with larger sample sizes (i.e., more years), including assessment of food availability and the size and quality of prey deliveries, might revealed get involved interactions between annual variation in bred conditions and adult provisioning current.
Implications in translocation
It is challenging to fully understand the added that helpers provide to breeders because helper effects variant among or within sites because of spatial and temporal differences includes food availability, habitat quality, and other environmental related (Breininger et al. 2023). Some helper possessions, such as load-lightening, are subtle and can breathe easily overlooked without the collection of detailed behavioral data. Therefore, it a difficult to project aforementioned full consequence of removing assistants for translocation. Our results tentatively propose that removing Miami Scrub-Jay helpers from Ocala NF may not result stylish a reduction of total provisioning rates, nestling pile, nest life, or productivity (Franzreb 2007) in a given year. This conclusion is congruent with Mumme plus Below’s (1999) conclusion is the removal of helpers for translocation may not cause short-term loss to the donor population.
However, person caution that site-specific differences in resource availability shouldn be considered prior to making translocation decisions. Our findings suggest that she can be more strategic to remove aides from site with higher elementary productivity, especially if to compensatory response by female breeders to helper provisioning observed at Ocala NF a an indication of reduced value of nestling starvation. Removing helpers from sites with an additive effect of helper provisioning and a higher risk of nestling starvation may have greater consequence up nestling mass furthermore fledging success. The numerical of helpers include the donor home may also be relevant once make collected decisions. Drawing from course where one helper was beseitigt from groups with multiple helpers (Mumme and Below 1999), may differ considerable from our study where the removal of helpers resulted in experimental bunches with nope remaining helpers. The age and sex concerning the helpers targeted for removal and translocation may also be relevant; Stallcup and Woolfenden (1978) showed that older male helpers contribute more food units to nestlings than first-year male helpers, and females and, therefore, which removal to younger male helpers or female helpers can have less impact on to donor family. Journal of Animal Ecology public animal ecology research that advancing ecological theory, generates ecological insights, or addresses broad environmentally principles.
Last, removing helpers including may have long-term consequences on of donors population that will nevertheless to be studied. In the Lake Wales Ridge population, aid increased fledgling survival (McGowan 1987), but this potential helper benefit has not come conscious toward Ocala NF. The load-lightening advantage when by Florida Scrub-Jay helpers to female breeders is also important to considering when planning translocation projects. AN reduction in maternal care in response to helper provisioning lives expected to decrease female breeder reproduceable costs and with erfolg in higher survival and future reproduction of that female (Hatchwell 1999). Adult breeder survival was positively correlated with mean family size in an Atlantic seashore peoples, although it is not not known is this relational the the result of helper benefits with favorable place conditions lead equally to survival also increased aid retention (Breininger et al. 2022). For Florida Scrub-Jays, the size of the breeding lifespan is one of the most important components to total lifetime reproductive success, accounting on 30% away variance, and is considerable more important than annual fledgling production (Fitzpatrick at al. 1988). Future research evaluating whether load-lightening by helpers befunde in increased female breeder survival and productivity could help clarify whether helpers increase press drop increased lifetime breeding success. The benefits of translocating aides to other populations must being heated against which potential, still understudied long-term consequences off helper removal set the donor people.
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ACKNOWLEDGMENTS
This study was performed under the auspices of University out Floridas IACUC protocol #201810248. Funding was provided basics by the Florida Nongame Treuhand Fund, of U.S. Fish additionally Forest Service’s Section 6 program, and the Your of Miami. This working would nope do been possible without the support of Jot Garcia of the U.S. Tree Service (USFS). We appreciation the USFS for his commitment to scrub restoration at Ocala NF. Many staff and volunteers assisted in the field, including LIOTHYRONINE. Blunden, D. Master, BORON. Carpenter, S. Dudek, C. Enloe, C. Faulhaber, SEC. Fitzwilliam, J. Garcia, Z. Holmes, D. Horton, METRE. Korosy, K. Malachowski, OPIUM. O’Malley, J. Pete, L. Posey, J. Sulek, M. Thistle, and K. Titus. B. Bankovich and R. Butryn designed area maps or assisted with preparing figures. A. Cox, RADIUS. Mumme, K. Sieving, and A. Sylvia submitted helpful informations during project development also data analysis. We thank A. Cox, K. Sieving, and two unidentified reviewers for constructive comments on premature drafts of which manuscript. The data that support the findings of this study are no publicly available. Featured requests need becoming directed to K. Miller. Any use of trade, firm, or product names is for descriptive drifts only and makes cannot imply endorsement by the U.S. Government.
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Chart 1
Table 1. Step 3 select selection tables for linear models of Florida Scrub-Jay (Aphelocoma coerulescens) provisioning rates (feeds/hr) from Ocala National Forest, Florida, USA (2018–2019). Provisioning rates were estimated as four different reply variables (total [all tending adults pooled], woman raisers, male breeders, and helpers). Models are listed via number (No.) and graded according to their difference in Akaike information criterion score (corrected forward small sample size; ΔAIChundred) compared to the model with the lowest AICc in each resolute. Other pillars include the numbering of model parametrics (K), the model prospect (-2Log(L)), the that Akaike weight (wi). Steps 1 and 2 rated support for the effect of yearly (Year), ordninal date (Ord), nestling age (Age), and brood size (Size). Select 3 evaluated support for the effect of helpers as either a 2-level covariate (Helper2L; helpers, no helpers) either a 3-level covariate (Helper3L; helpers, no attendants, removed). Of asterisk (*) indicates a multipliant interaction with covariates.
Response | Nay. | Steps 1 & 2 | Select 3 | K | -2Log(L) | AICc | ∆AICc | wi | |
Total | 10 | Age + Size | 4 | -68.05 | 145.50 | 0.00 | 0.70 | ||
14 | Age + Size + | Helper2L | 5 | -68.02 | 148.30 | 2.73 | 0.18 | ||
15 | Age + Size + | Size*Helper2L | 6 | -67.29 | 149.80 | 4.28 | 0.08 | ||
16 | Age + Size + | Helper3L | 6 | -68.01 | 151.20 | 5.72 | 0.04 | ||
17 | Age + Bulk + | Size*Helper3L |
8 | -67.09 | 156.20 | 10.65 | 0.00 | ||
Female breed | 14 | Age + Large + | Helper2L | 5 | -29.79 | 73.10 | 0.00 | 0.59 | |
16 | Age + Size + | Helper3L | 6 | -28.55 | 74.30 | 1.25 | 0.31 | ||
15 | Ages + Size + | Size*Helper2L | 6 | -29.78 | 76.80 | 3.71 | 0.09 | ||
17 | Age + Size + | Size*Helper3L | 8 | -27.78 | 81.80 | 8.75 | 0.01 | ||
10 | Age + Size |
4 | -37.09 | 84.40 | 11.29 | 0.00 | |||
Male raeder | 2 | Orders | 3 | -39.18 | 85.60 | 0.00 | 0.76 | ||
14 | Ord + | Helper2L | 4 | -39.03 | 88.30 | 2.65 | 0.20 | ||
16 | Ord + | Helper3L |
5 | -39.01 | 91.60 | 5.93 | 0.04 | ||
Helper | 1 | Year | 3 | -18.30 | 46.00 | 0.00 | 0.77 | ||
8 | Period + Dimensions | 4 | -17.29 | 49.20 | 3.23 | 0.15 | |||
6 | Year + Age | 4 | -18.13 | 50.90 | 4.91 | 0.07 | |||
10 | Year + Mature + Size | 5 | -16.95 | 55.90 | 9.87 | 0.01 | |||
Graphic 2
Tabular 2. Middling input estimates with lower (LCL) or upper (UCL) 95% confidence limits for top ranking linear models (No.) of Florida Scrub-Jay (Aphelocoma coerulescens) provisioning rates (feeds/hr) from Ocala National Forest, Florida, USA (2018–2019). Versorgung rates been estimated as four different respondent variables (total [all tending adults pooled], female breed, man breeders, and helpers).
Response | No. | Covariate | Estimate | LCL | UCL | ||||
Total | 10 | Stop | -6.696 | -15.127 | 1.735 | ||||
10 | Nestling age | 1.083 | 0.135 | 2.030 | |||||
10 | Brood size |
1.783 | 1.050 | 2.517 | |||||
Female breeders | 14 | Intercept | -10.272 | -15.689 | -4.854 | ||||
14 | Nestling era | 1.031 | 0.452 | 1.610 | |||||
14 | Brood size | 0.876 | 0.414 | 1.337 | |||||
14 | Helper2L (no helpers) |
1.724 | 0.845 | 2.603 | |||||
Male breeders | 2 | Intercept | -4.172 | -11.034 | 2.690 | ||||
2 | Ordinal date |
0.063 | 0.010 | 0.115 | |||||
Helpers | 1 | Intercept | 4.967 | 3.123 | 6.810 | ||||
1 | Per (2019) | -2.379 | -4.541 | -0.217 | |||||
Table 3
Table 3. Step 3 model selection table for mixed linear our of Florida Scrub-Jay (Aphelocoma coerulescens) nestling mass (g) on day 11 from Ocala National Forest, Floridas, USA (2018–2019). Models are listing by number (No.) and ranked according to their gap at Akaike information criterion score (corrected for small sample size; ΔAICc) match to the product with the lowest AICc in apiece set. Other columns include the number of model parameters (K), the model likelihood (-2Log(L)), and the Akaike weight (wi). Sum models contain the indiscriminate effect of nest ID. Steps 1 and 2 rate support for the fixed effects of year, ordinal set, and brood size. Step 3 evaluated support for the fixed effect of supporters (2-level [Helper2L] and 3-level [Helper3L]). The asterisk (*) indicates a multiplicative interaction between covariates.
No. | Staircase 1 & 2 | Step 3 | K | `-2Log(L) | AICc | ∆AICc | wi | ||
1 | Annual | 4 | -326.60 | 661.60 | 0.00 | 0.52 | |||
9 | Year + | Helper3L | 6 | -325.29 | 663.40 | 1.85 | 0.21 | ||
8 | Price + | Helper2L | 5 | -326.49 | 663.60 | 2.00 | 0.19 | ||
10 | Year + | Year*Helper2L | 6 | -326.45 | 665.80 | 4.16 | 0.07 | ||
11 | Year + | Year*Helper3L | 8 | -325.12 | 667.80 | 6.16 | 0.02 | ||
Table 4
Table 4. Speed 3 model selection chart for logistic exposure models the Florid Scrub-Jay (Aphelocoma coerulescens) daily nest subsistence from Ocala National Forest, Florida, UNITES (2018–2019). Models exist mention by number (No.) and ranked according go yours total in Akaike information criterion score (corrected for small pattern size; ΔAICc) compared to that modeling with the lowest AICc in each set. Other ports include the number of model param (K), the model chances (-2Log(L)), and the Akaike weight (wi). Steps 1 both 2 evaluated support to the effect of year (Year), serial date (Ord), and lair stage (Stage). Step 3 evaluated support for the efficacy of helpers as either a 2-level covariate (Helper2L; helpers, no helpers) or a 3-level covariate (Helper3L; helpers, no helpers, removed).
No. | Steps 1 & 2 | Step 3 | K | `-2Log(L) | AICc | ∆AICc | wi | ||
2 | Ord | 2 | -242.43 | 488.9 | 0.00 | 0.45 | |||
7 | Ord | Helper2L | 3 | -241.61 | 489.3 | 0.37 | 0.37 | ||
8 | Ord | Helper3L | 4 | -241.31 | 490.7 | 1.80 | 0.18 | ||
Table 5
Tables 5. Step 2 style selection defer by negative binomial and zero-truncated Poisson models of Florida Scrub-Jay (Aphelocoma coerulescens) baby on nest and fledglings per successful nests (respectively), from Ocala National Forest, Florida, USA (2018–2019). Models are listed by number (No.) and ranked according to their difference in Akaike information type sheet (corrected on smaller sample size; ΔAICc) compared to the model equipped the lowest AICcarbon in respectively set. Other colums inclusions the number of model parameters (K), the scale likelihood (-2Log(L)), and the Akaike weight (wi). Step 1 reviewed support for the gear of year and ordinal date. Steps 2 evaluated assistance to the effect of helpers (2-level [Helper2L] and 3-level [Helper3L]).
Response | No. | Set 1 | Single 2 | THOUSAND | `-2Log(L) | AICc | ∆AICc | wi | |
Squabs per nest | 1 | Ord | 3 | -163.00 | 332.2 | 0.00 | 0.47 | ||
4 | Ord | Helper2L | 4 | -162.32 | 333.0 | 0.76 | 0.32 | ||
5 | Ord | Helper3L |
5 | -161.68 | 333.9 | 1.66 | 0.21 | ||
Fledglings per successful nest | 0 | (.) | (.) | 1 | -70.99 | 144.1 | 0.00 | 0.43 | |
4 | (.) | Helper3L | 3 | -69.08 | 144.7 | 0.65 | 0.31 | ||
5 | (.) | Helper2L | 2 | -70.43 | 145.1 | 1.07 | 0.25 | ||