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CHARACTERISTICS OF BREEDING HABITAT AND HABITAT USE OF THE EASTERN PAINTED BUNTING IN FLORIDA

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Title:
CHARACTERISTICS OF BREEDING HABITAT AND HABITAT USE OF THE EASTERN PAINTED BUNTING IN FLORIDA
Series Title:
Undergraduate Thesis by Derrick Thrasher
Creator:
Sieving, Kathryn ( Author, Secondary )
Thrasher, Derrick ( Author, Primary )
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Gainesville, FL
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Department of Wildlife Ecology and Conservation, University of Florida
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2013
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English
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Undergraduate Thesis

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Abstract:
The Eastern painted bunting (Passerina ciris ciris), one of North America’s most notable neotropical migrants, has experienced a rapid population decline over the past 50 years. Information about habitat associations of this species throughout its range is poorly known. Recent investigation of population densities in Florida asserts that this knowledge is crucial to properly manage breeding habitat for buntings and curb the population’s decline. In this study we sought to (1) estimate spatial use of males in coastal scrub and maritime hammock habitats by measuring territory size, (2) infer differences in vegetative structure and composition that may influence territory size, and (3) investigate behavioral differences in males between coastal scrub and maritime hammock habitats. Territory size differed significantly between the two habitats, with territories located in maritime hammock being notably larger. Vegetative structure and vegetative composition differed significantly between the two habitats while few differences were identified in behavioral characteristics. We infer that territories in the maritime hammock may support a higher density of buntings, but protection and management of both habitats is necessary to conserve this species.
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Collected for University of Florida's Institutional Repository by the UFIR Self-Submittal tool. Submitted by Kathryn Sieving.
General Note:
This thesis was written in 2013 by Derrick Thrasher and Kathryn Sieving. Derrick Thrasher conducted all field work for this project while he was an undergraduate student.

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1 Present address: 2635 SW 35 th PL Unit #802, Gainesville, FL 32608. E mail: thrashersdutch@gmail.com D.J. Thrasher and K.E. Sieving 1 Eastern Painted Bunting Habitat Use in Florida 2 CHARACTERISTICS OF BREEDING HABITAT AND HABITAT USE OF 3 THE EASTERN PAINTED BUNTING IN FLORIDA 4 5 DERRICK J. THRASHER 1 AND KATHRYN E. SIEVING 6 7 Department of Wildlife Ecology and Conservation 8 University of Florida, Gainesville, Florida 32611, USA 9 10 11 12 13 14 15 16 17 18 19 20

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Thrasher 1 ABSTRACT 21 The Eastern painted bunting ( Passerina ciris ciris ), one of North America's 22 most notable neotropical migrants, has experienced a rapid population de cline over 23 the past 50 years. Information about habitat associations of this species throughout 24 its range is poorly known Recent investigation of population densities in Florida 25 asserts that this knowledge is crucial to properly manage breeding habitat for 26 buntings and curb the population's decline In this study we sought to (1) estimate 27 spatial use of males in coastal scrub and maritime hammock habitats by measuring 28 territory size, (2) infer differences in vegetative stru cture and composition that may 29 influence territory size, and (3) investigate behavioral differences in male s between 30 coastal scrub and maritime hammock habitats. Territory size differed significantly 31 between the two habitats, with territories located in maritime hammock being 32 notably larger. Vegetative structure and vegetative composition differed 33 significantly between the two habitats while few differences were identified in 34 behavioral c haracteristics. We infer that territories in the maritime hammock may 35 support a higher density of buntings, but protection and management of both 36 habitats is necessary to conserve this species. 37 38 Keywords: coastal scrub, maritime hammock, territory size, st ructure, composition, 39 behavior. 40

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Thrasher 2 INTRODUCTION 41 The Eastern painted b unting ( Passerina ciris cirsis ) is a neotropical migrant 42 which predominantly breeds along coastal regions from central North Carolina 43 south to Brevard County, Florida ( Lowther et al. 1999) The Eastern painted 44 bunting population is of great conservation concern due to its geographically 45 restricted range, particularly in North Carolina and Florida. The species has 46 experienced a dramatic population decline, and is listed by the U.S. Fish and 47 Wildlife Service as a "species of concern" under the Migratory Bird Program 48 Strategic Plan 2 004 2014. Breeding Bird Surveys ( 1966 2003 ), show a decline of 49 0.5 % per year on average in Florida reporting an estimated population of well less 50 than 5 00,000 breeding adults with no definitive reasons for the decline recognized 51 (Sauer et al. 2007). E xtensive coastal development is thought to be the primary 52 factor in the decline of bunting populations; as a result of the species' narrow 53 geographic range, it is particularly susceptible to habitat loss and fragmentation 54 (Lowther et al. 1999). 55 Habitat associations of the species throughout the breedi ng range are not well 56 characterized but are known to include particularly open areas with scattered 57 patc hes of brush and trees, t h ickets along riparian corridors, and generally shrubby 58 habitat (AOU 1998). On Sapelo Island, Georgia, Eastern painted buntings use d 59 habitats that ha d significant amounts of edge, including early successional forests, 60

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Thrasher 3 pastures, f allow fields bordered by woodlands, and maritime shrub scrub 61 (Springborn and Meyers 2005). In Northeast Florida, preliminary studies describe 62 Eastern painted b untings as occupying "beach scrub, thickets, and disused citrus 63 groves" along the St. Johns River (Robertson and Wool fenden 1992). The 64 proximity of these habitats to grassy fields is imperative for foraging adults and 65 fledglings, and it is probable that this is a defining component of territory selection 66 (Lowther et al. 1999 ) Three major habitats hav e been characterized as important 67 areas for Eastern painted buntings to persist throughout their range in Florida. 68 These include coastal scrub, maritime hammock, and agricultural or disturbed 69 areas (Delany 2010 ). Since the birds occupy such diverse habitat in Florida, it is 70 intuitive to think that habitat type will largely affect settlement, defense, and size 71 of breeding territories. Differences in vegetation composition and structure may 72 influence a divergence in habitat use between habitats, as it relates to factors such 73 as nesting and foraging microhabitat selection in addition to routine daily 74 behavior Coastal scrub and maritime hammock dominate a large portion of the 75 breeding habitat in Florida and were the focal habitats in our study. The objectives 76 of our study were to (1) estimate spatial use of male Eastern painted buntings in 77 coastal scrub and maritime hammock habitats by measuring territory size, (2) infer 78 differences in vegetative structure an d composition that could influence territory 79

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Thrasher 4 size, a nd (3) investigate behavioral differences in male Eastern painted buntings 80 between coastal scrub and maritime hammock habitats. 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99

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Thrasher 5 METHODS 100 Study a rea 101 We conducted our study in northeast Florida, at four protected areas between 102 Fernandina Beach, FL and Jacksonville, FL from April to July 2010 The Florida 103 Department o f Environmental Protection manages three of the sites including: Fort 104 Clinch State Park (FCSP), Big Talbot Island State Park (BTSP), and Little Talbot 105 Island State P ark (LT SP ) The fourth site, located just north of Jacksonville was 106 the Timucuan Ecological and Historical National Preserve (TIMU) owned and 107 managed by the U.S. National Park Service (Figure 1) We categorized each site 108 into areas of coastal scrub or ma ritime hammock based on proximity to fore dunes 109 and by distinguishable vegetation characteristics Coastal scrub was typically 110 located within 50 100 meters of the fore dunes and was characterized by dense 111 undergrowth of salt tolerant shrubs, patchy vegetation, and extensive areas of open 112 bare sand (FL NAI and FL DNR 1990). Maritime hammock varied greatly in 113 distance from the fore dunes and was characterized by mixed hardwood species, 114 mesic conditions, and high canopy with an understory shrub layer. Maritime 115 hammock was usually bordered by salt marsh dominated by Spartina spp. LTISP 116 consisted primarily of coastal scrub, BTISP and TIMU consisted primarily of 117 maritime hammock bordered by salt marsh, and FCSP was composed of both 118 habitat types. 119

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Thrasher 6 Territor y m apping 120 W e used territorial playback techniques to assess the territory sizes of male 121 bunting s from April May 2010 ( Falls, 1981 ) Male buntings were detected either 122 visually or aurally between the hours of 6:00 11:00 and 16:00 19:00. Upon 123 detection, the recorded song of a conspecific from South Carolina was played for 124 an interval of five minutes or until a territorial response was elicited We 125 characterized a territorial response as rapid approach, calling or singing, and 126 displaying withi n five meters of the speaker. If no response was elicited within 127 five minutes the point was assumed to be outside of the defended territory and was 128 marked as a potential boundary Once a territorial response was elicited, the 129 speaker was immediately moved to a new position and the aforementioned steps 130 were repeated until 10 15 boundary points were determined, generally 131 representative of the four cardinal directions. If a bird lost interest in the playback, 132 the survey was repeated the following day until an appropriate number and 133 distribution of points we re obtained. Male buntings that could not be adequately 134 mapped were noted only as being present. Neighboring birds that were detected 135 during the survey were noted and sequentially surveyed beginning at t he point they 136 were initially detected at 137 Points were collected using handheld GPS units and were georeferenced using 138 Google Earth. GE Path was used to connect all outside boundary points and 139

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Thrasher 7 compute polygon area, in order to estimate the total defe nded territory area in 140 hectares. Each territory estimate was categorized by habitat type. In our analysis of 141 territory size, we only included birds which had territories with at least 10 15 142 well distributed points ( n=17 ). We used a t test assuming unequa l variance to 143 determine if territory size differed between habitats. 144 Vegetation s ampling 145 Five territories were randomly selected in each habitat and an approximate 146 center point was estimated for each selected territory. Four, 10 meter line transects 147 w ere placed in each selected territory at a random orientation from 0 360 and a t 148 random selected distance from the estimated center point (limited by mean 149 territory diameter) A 10 meter buffer was applied around the interior edge of the 150 territories, in which no transect was placed in order to ensure that the line transect 151 was contained within the estimated territory area. Vegetation composition and 152 structure were measured to a height of three meters along each transect, in strat a of 153 0 1 m, 1 2 m, and 2 3 m. All vegetation and substrate along transects were 154 categorized by species or type, and then by patch length. Every occurrence of a 155 species or substrate along each transect was treated as a new patch, and the stratum 156 at which each occurred was recorded. The highest height stratum that vegetation 157 within a patch reached was recorded as maximum patch height. Individual grass 158 species were combined to form the group, g rasses." We adapted a method for 159

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Thrasher 8 quantifying structure from Martin's BBird protocol (1997) to measure stem 160 densities from 2 8 meters along each transect at 2 meter intervals. Live and dead 161 stems of any diameter were counted at every point and recorded by height in 162 stratum of 0 1 m, 1 2 m, and 2 3 m. Another adaptation of the BBird protocol wa s 163 used to roughly estimate canopy cover near each transect by visual estimate. 164 Our analysis focused on understanding the general composition and structure of 165 each habitat type. To estimate composition, we determined the proportion of each 166 species of vegetation or substrate relative to the total amount of cover measured 167 on each territory. We extrapolated percent cover estimates for each habitat based 168 on mean measurements of each species or substrate across the territories. We 169 inferred structure based on mean stem density estimates and the frequency of 170 patches within each height stratum. We conducted a 1 way M ANOVA in SPSS to 171 test whether mean stem density differed between habitats at each stratum ( 0 1 m, 172 1 2 m, and 2 3 m height ) 173 Behavior al o bservations 174 We observed behaviors of male painted buntings using focal animal sampling 175 over a total of 50 hours from June July 2010. We categorized behaviors as four 176 different activities: flying, foraging, preening, and vocalizing. We surveyed for 177 male buntings between 6:00 11:00 and began focal behavioral observation s as 178 soon as a bird was visually detected (Martin and Bateson 2007) The o bservation 179

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Thrasher 9 period varied as a result of the time that a bird could be observed and observation s 180 ceased when a bird could no longer be seen. During an observation period, the bout 181 length and type of behavior were recorded every time that a bird exhibited one of 182 the target behaviors. During each bout, the plant or substrate that the behavior was 183 being observ ed on was recorded. In our analysis, we used SPPS to conduct a series 184 of 2 way ANOVA s to test if the mean time that we observed birds conducting a 185 target behavior differed between habitats. In order to infer information regarding 186 habitat use in territory defense, we quantified the proportion of time that birds were 187 observed singing from different plant species in each habitat. 188 189 190 191 192 193 194 195 196 197 198 199

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Thrasher 10 RESULTS 200 Territory m apping 201 We located 24 territories, 13 in coastal scrub and 11 in maritime h ammock, 202 distributed across all four sites Five of the birds detected were identified as after 203 hatch year males because of their green, female like plumage, with four being 204 found in coastal scrub, and one in maritime hammock. 17 of the 24 territories were 205 able to be mapped an d the size s estimated (Table 1) Territory size was 206 significantly greater in coastal scrub than in the maritime hammock ( Figure 2, x = 207 3.45 + .19 vs. x = 1.71 + .22; t test assuming unequal variances, t = 2.15, df = 14, 208 P = .00002). 209 Vegetation s ampling 210 In the maritime hammock, canopy cover was typically between 75 95% and in 211 the coastal scrub canopy cover ranged from approximately 0 20%. 39 total 212 species of plants were detected between both ha bitats. Both habitats shared li tter 213 cover, sand, grasses, and six plant species. In the coastal scrub, 16 of the 22 total 214 species detected were unique to that habitat and in the mari time hammock 17 of 215 the 23 total species were unique. Species which composed more than 4 % cover on 216 at least one transect were considered significant enough to be calculated in percent 217 cover estimates by habitat. Species which composed less than 4 % cover on at least 218 one transect were compiled as "other" and assessed only as present or absent 219

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Thrasher 11 (Table 2). In coastal scrub the three dominant covers were earleaf greenbrier, sand, 220 and wax myrtle. In maritime hammock the three dominant covers were plant litter, 221 saw palmetto, and grasses ( Figure 3 ) 222 Stem density was significantly different between coastal scrub and maritime 223 hammock at 0 1 m in height ( F 1,36 = 14.29, P = .001) and at 2 3 m in height 224 ( F 1,36 = 4.19, P = .047). There was no difference in ste m density between coastal 225 scrub and maritime hammock at 2 3 m in height ( F 1,36 = 1.89, df = 1, P = .177) 226 (Figure 4) 227 Behavioral o bservation s 228 Observations were made o n four territories in coastal scrub and three in the 229 maritime hammock. Mean bout length was 92.02 seconds in coastal scrub and 75.4 230 seconds in the maritime hammock. Of the four main behaviors, there were no 231 significant differences in the time spent vocalizing, flying, or preening between the 232 two habitats (Figure 5) Foraging was extremely difficult to ob serve in scrub, 233 therefore no statistical c omparison was made 234 V ocalizing male buntings sang from vegetation that was typically 5 7 m 235 above ground level. The vegetation that was used as singing perches varied greatly 236 with habitat and most singing perches were exposed branches above the major ity 237 of the vegetation. In coastal scrub, male buntings were observed vocalizing on six 238 different perch types, with the dominant perches being on the southern hackberry 239

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Thrasher 12 tree and the eastern red cedar. In maritime hammock, they were observed 240 vocalizing on ei ght different perch types, with the dominant perch being on 241 oak/pine snags (Figure 6). 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259

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Thrasher 13 DISCUSSION 260 The coastal scrub and maritime hammock habitats exhibited several differences 261 in structure, composition, and function which influenced the ways that male 262 painted buntings used the habitats. The vegetative communities in each habitat 263 were different in structure and diversity, likely contributing to the notable 264 differences found in territory size and to a lesser extent, behavioral time budg ets. 265 Habitat based territory differences 266 We found a significant difference in territory size of male buntings between the 267 coastal scrub and maritime hammock with territories in the coastal scrub being 268 twice as large as those in the maritime hammock. In terrestrial habitats, marshes 269 have been identified as exhibiting the highest levels of net primary productivity 270 (Whitaker and Likens 1973), and this may cause higher d ensities of foods for 271 buntings, primarily insects in the breeding season ( Lowther 1999 ). All maritime 272 hammock territories were bordered by salt marsh, and the smaller territory sizes 273 may therefore be explained by the productivity of the salt marsh. Additionally, we 274 noted that territories in the maritime hammock were largely contiguous, whe reas 275 territories in the coastal scrub tended to be more disjunct from one another (on 276 average approx. 100 150 m between territory boundaries). Therefore, population 277 densities in scrub are likely to be much lower overall than simple territory size 278 compar ison would suggest. In Missouri, the average size of western painted 279

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Thrasher 14 bunting territories estimated using spot mapping was 1.4 ha in areas of high 280 density (Norris and Elder 1982). This is comparable to the territory size of 1.71 ha 281 that we observed in the maritime hammock. The average size of territories 282 estimated in the coastal scrub was 3.45, which is also very similar to the estimated 283 3.2 ha in areas of Missouri that have been identified as having low bunting 284 densities (Norris and Elder 1982). These para llels suggest that bunting densities 285 and territory sizes in different habitats can be very different, a pattern found in 286 several other passerine species (Khoury 2010). On St. Catherine's Island, Georgia, 287 male painted buntings established territories in a stacked manner from the salt 288 marsh edge well in to the interior of the maritime hammock (Lanyon & Thompson 289 1986). We noticed no such pattern in maritime hammock territories at our study 290 sites, with buntings only existing along the salt marsh and maritime ha mmock 291 edge. In the coastal scrub, we found that te rritories were associated with large areas 292 of brush and were arranged in a patchy distribution. The restriction of males to the 293 salt marsh/ maritime hammock edge could be attributed to a reduction of brushy 294 vegetation and productivity as distance from the salt marsh increased. 295 Impacts of vegetative community on habitat use 296 Vegetation structure and composition are major factors involved in avian 297 selection of microhabitat particularly for nesting an d foraging that in turn 298 influence reproductive success (Fuller and Henderson 1992). Vegetative 299

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Thrasher 15 community composition and structure of coastal scrub and maritime hammock 300 territories were quite different in some ways, but had important similarities that 301 help explain the species occupancy within both. A central similarity is that both 302 habitats were characterized by a large portion of open area in the understory, with 303 plant litter being the primary substrate in the maritime hammock and bare sand 304 being the primar y substrate in the coastal scrub. This is likely a key requirement 305 for buntings because they rely on capturing insects to feed you ng during the 306 breeding season and the open ground may provide th em with important foraging 307 area, not only for provisioning you ng, but also themselves (Ehrlich et al. 1988, 308 Sutherland et al. 2004). 309 Other than the percentage of bare ground, scrub and hammock vegetative 310 community composition and vertical structure were very different. While we 311 encountered similar plant species richness in both habitats, only 6 of 39 species 312 occurred in both coastal scr ub and maritime hammock. The vegetative 313 communities of both habitats consisted of species that are highly adapted to persist 314 in harsh and fluctuating conditions, but soil conditions and hydrology probably 315 explain the floristic differences. The maritime ham mock expressed mesic 316 conditions and the plant community was chiefly influenced by nutrient cycling via 317 detrital organisms in the adjacent salt marsh (FL NAI and FL DNR 1990). The 318

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Thrasher 16 coastal scrub plant community was characterized by their salt blown shrubs i n 319 nutrient poor, sandy soil, and xeric conditions (FL NAI and FL DNR 1990). 320 Vegetation structure was also quite different between habitats. Since buntings 321 are mainly an understory forager and nester, we assumed that the configuration of 322 plants at diff erent stratum distinctively affected the way the birds selected and used 323 microhabitat (MacArthur and MacArthur 1961). Stem density, on average, was 324 much greater in the coastal, particularly within the understory below 2 meters. 325 Veg etation in the coastal sc rub exhibited a patchy mosaic of vegetation patches 326 and bare sand, with several species occupying the limited areas suitable for plant 327 growth. The restri ction of plant growth to isolated patches was less prevalent in the 328 maritime hammock, and plant matter was more uniformly distributed. This 329 explains the significant difference in stem den sity below 2 m in height between the 330 habitats. In the 2 3 m stratum, stem density was not significantly different 331 between habitats and this is likely a result of the ext ensive branching of the lower 332 shrub layer in both the coastal scrub and maritime hammock observed at this 333 height. Fruiting bodies were observed in many species at this stratum and it may 334 serve as crucial foraging microhabitat for adult between territory se ttlement and 335 onset of reproduction in both habitats. 336 Our methods may have under sampled the species richness of these 337 communities, because some plant species not detected on line transects were 338

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Thrasher 17 observed being used as perches in territory defense (Figu re 6). We suggest that 339 using the Modified Whit t aker technique and sampling nested quadrats of 1m 2 340 10m 2 and 100m 2 in random 20m x 50m plots would overcome this problem 341 (Stohlgren et al. 1995) 342 Behavior al time budgets 343 Data on flying, vocalizing and perching was the most reliable behavioral data 344 collected because of the ease at which these behaviors could be observed. The 345 average time observed conducting each of these behaviors was very similar 346 between the two habitats. We detected differences in foraging but it was generally 347 difficult to observe, especially in scrub; therefore we conclude nothing about 348 potential differences in foraging time between the two habitats. However, based on 349 the similar times allocated to the m ore visible behaviors in the two habitat types, 350 we conclude that habitat differences are not likely to be influencing time and 351 energy budgets in important ways. A caveat to this may lie in the large difference 352 in size of the territories we documented, as t his suggests that one important 353 difference may lie in territory defense and the amount of time/energy it takes to 354 patrol larger areas in scrub. However, we also noted that coastal scrub birds had 355 fewer, sparser neighbors than birds in the maritime hammock, suggesting that birds 356 living there may suffer fewer territory intrusions than birds in the maritime 357 hammock. As a result, territorial defense costs could be significantly higher for the 358

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Thrasher 18 maritime hammock birds. On balance, then, the data we have suggest t hat the two 359 different costs may cancel out' in that increased defense in one habitat may 360 require similar efforts as increased patrol in the other. Without more information, 361 we cannot say whether there are habitat related differences in time and energy 362 exp enditures, but suspect there are not. As in Springborn and Meyer's (2005) study 363 at Sapelo Island, Georgia, the application of radio telemetry would be fruitful in 364 understanding more about macro and micro habitat utilization in this species. 365 Radiotelemetry may also be the only efficient technique for finding nests of 366 painted buntings, and would aid in reproductive success monitoring; we 367 recommend that future bunting studies in Florida, utilize this technique (Powell et 368 al. 2005) 369 Conservation implications 370 Florida constitutes the southern extent of the eastern painted bunting's breeding 371 range (Lowther et al. 1999) As a species which is limited by s ize and location of 372 its breeding range, protection of all areas which the birds persist in is necessary in 373 order to mitigate the effects of previously experienced habitat fragmentation and 374 loss. Studies in the last few decades suggest that the breeding range in Florida has 375 expanded southward and inland (Taylor 1989) While this expansion is optimistic 376 for the s pecies, these inland breeding sites are often short lived, intermittent, and 377 localized (Sykes and Holzman 2005). Partners In Flight estimate d the total 378

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Thrasher 19 population of the eastern painted bunting to be 93,928 individuals, with 7,479 or 379 7.9% of those being in Florida (PIF 2007) Florida, being the farthest extent of the 380 eastern painted bunting s range, may experience extensive variation in numbers of 381 birds and low population size (Delany 2010). These low numbers and potential 382 variability make the species sligh tly more vulnerable to habitat level changes in 383 Florida. 384 Coastal scrub is likely the most endangered habitat in Florida (FL NAI and FL 385 DEP 1990). Development of coastal areas for anthropogenic ventures is a probable 386 and generally accepted cause of lo ss and fragmentation of coastal scrub. Further 387 change to this habitat could be detrimental to buntings in Florida if inland breeding 388 attempts continue to be intermittent and localized, since the species is normally 389 restricted to coastal are as. Other than the obvious need for conse rvation of coastal 390 lands and dune protection few management practices are recommended in 391 protected coastal areas because of the intense oceanic pressures imposed, which 392 maintain open shrubby areas (Springborn and Meyers 2005). Th e edge habitat 393 between maritime hammock and salt marshes appears to be especially productive 394 for painted buntings in Florida and limited management is needed when this 395 habitat has significant open area (Delany 2010). To improve areas of maritime 396 hammock wh ich have become unsuitable for breeding buntings, management 397

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Thrasher 20 practices should involve opening of the upper canopy to allow the growth of 398 understory grasses and shrubs (Myers 2004). 399 Without reproductive output estimates, we can only suggest that mariti me 400 hammock is the most important of the two habitat types analyzed in this study 401 based on the likelihood that population densities of buntings may be more than 402 twice as high in hammock than in scrub. Not only are scrub territories larger in 403 area, but their boundaries are not contiguous as they are in hammock. Further 404 research on reproductive success is needed, however, to provide crucial 405 information for understanding population viability across the habitats buntings 406 occupy (Johnson 2007) Therefore, we rec ommend that efforts to estimate 407 productivity of the Florida populations be made a high priority in future 408 assessments of Eastern painted bunting status. 409 410 411 412 413 414 415 416 417

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Thrasher 21 ACKNOWLEDGMENTS 418 We would like to thank t he University of Florida Institute of Fo od and 419 Agricultural Sciences and the Florida Ornithological Society for providing funding 420 for this study The Florida Department of Environmental Protection and the 421 Timucuan Ecological and Historical Preserve (NPS) provided use of their land for 422 study site s. We would like to thank Stephen Harris, Lindsay Wagner, Emma 423 Knight, and Emily Williams of the Department of Wild l ife Ecology University of 424 Florida, for their extensive assistance in the field We would also like to give a 425 special thanks to Mike Delany of the Florida Fish and Wildlife Conservation 426 Commission for his guidance on study site and habitat selection, as well as overall 427 guidance throughout the study. 428 429 430 431 432 433 434 435 436 437

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Thrasher 22 LITERATURE CITED 438 AOU. 1953. A Checklist of North American Birds, fifth ed ition. American 439 Ornithologists Union, Washington, D.C. 440 Delany, M. F. 2010 Eastern painted bunting m onitoring: Final r eport. Florida Fish 441 and Wildlife Conservation Commission. 442 Ehrlich, P.R., D.S. Dobkin, and D. Wheye. 1988. The birders handbook: A field 443 guide to the natural history of North American birds. 560. Simon and 444 Schuster, Inc. New York, NY. 445 Falls, J.B. 1981. Mapping territories with playback: an accurate census method for 446 songbirds. Studies in Avian Biology. 6:86 91. 447 FNAI. 1990. Guide to the natural commu nities of Florida. Florida Natural Areas 448 Inventory and the Florida Department of Natural Resources. 449 Fuller, R.J. and B. Henderson. 1992. Distribution of breedi ng songbirds in 450 Bradfield Woods, Suffolk, in relation to vegetation and coppice 451 management Bird Study. 39: 73 88. 452 Google Earth 5.0, 2010 Northeast Florida Landcover Data Layer. [Accessed 10 453 December 2010]. Available from: http://www.google.com/earth/. 454 GE Path. 2009 GE Path: Area Mapping Software. Version 1.4.4a Ilheus, Bahia 455 Braz il Cocoa Rese arch Center. 456

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Thrasher 23 Johnson, M.D. 2007. Measuring habitat quality: a review. The Condor. 109: 489 457 504. 458 Khoury, F. and M. Boulad. 2010. Territory size of the Mourning Wheatear 459 Oenanthe lugens along an aridity gradient Journal of Arid Environments 460 74 : 1413 1417 461 Lanyon, S. M., and C. F. Thompson. 1986. Site fidelity and habitat quality as 462 determinants of settlement pa ttern in male Painted Bunting. The Condor 463 88:206 210. 464 Lowther, P. E., S. M. Lanyon, and C. W. Thompson. 1999. Painted Bunting 465 ( Passerina ciris ) In : The Birds of North America, No. 398. A. Poole and 466 F. Gill, eds. The Birds of North America, Inc. Philadelphia, Pennsylvania. 467 MacArthur, R.H. and J W. MacArthur 1961. On Bird Species Diversity 468 Ecology 42 : 594 598 469 Martin, P. and P. Bateson. 2007. Measuring behavior: An Introductory Guide. 470 Third edition. Cambridge University Press. Cambridge, UK. 471 Martin, T.E., C.R. Paine, C.J. Conway, W.M. Hochachka, P. Allen, and W. 472 Jenkins. 1997. BBIRD Field Protocol Montana Cooperative Wildlife 473 Research Unit, University of Montana, Missoula, Montana, USA. 474 Myers, J. M. 2004. Bird without equal: The story of Georgia's Painted Bunting. 475 Downloadable from http://www.pwrc.usgs.gov/pabu/ 476

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Thrasher 24 Norris, D.J. and W.H. Elder. 1982. Distribution and habitat characterist ics of the 477 painted bunting in Missouri. Transactions of the Missouri Academy of 478 Sciences. 16: 77 83. 479 PIF 2007. Partners In Flight landbird population estimate database 480 [ http://www.rmbo.org/pif_db/laped/default.aspx March 2010] 481 Powell, L.A., J.D. Lang, D.G. Krementz, and M.J. Conroy. Use of radio telemetry 482 to reduce bias in nest searching. 2005. Journal of Field Ornithology. 76: 274 483 278. 484 Robertson, W. B., Jr., and G. E. Woolfenden. 1992. Florida bird species: An 485 annotated list. Florida Ornithological Society, Special Publication 6. 486 Sauer, J. R., J. E. Hines, and J. Fallon. 2008. The North American Breeding Bird 487 Survey, Results and Analysis 1966 2007. Version 5.15.2008. USGS 488 Patuxent Wildlife Research Center Laurel, MD [http://www.mbr 489 pwrc.usgs.gov/b bs/bbs.html, March 2010]. 490 Springborn, E. G., and J. M. Meyers. 2005. Home range and survival of breeding 491 painted buntings on Sapelo Island, Georgia. Wildlife Society Bulletin. 492 33:1432 1439. 493 SPSS for Windows. 2011. Rel. 18.0.1 Chicago. SPSS Inc. 494

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Thrasher 25 Sutherland, W.J., I. Newton, and R.E. Green. 2004. Bird Ecology and 495 Conservation: A handbook of techniques. Oxford U niversity Press. New 496 York, NY. 497 Stolhgren, T.J., M.B. Falkner, and L.D. Schell. 1995. A modified Whittaker nested 498 vegetation sampling method. Plant Ecology. 117: 113 121. 499 Sykes, P. W., Jr., and S. Holzman. 2005. Current range of the eastern population 500 of Painted Bunting (Passerina ciris). North American Birds 59:4 17. 501 Whittaker RH, Likens GE. 1973. Carbon and the biota. Brookhaven Symp. Biol 502 24:281 302 503 504 505 506 507 508 509 510 511 512 513 514

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Thrasher 26 Table 1. Estimated territory sizes of eastern painte d buntings at protected areas in northeast Florida (FCSP = Ft. Clinch State Park, LTSP = Little Talbot Island State Park, BTSP = Big Talbot Island State Park, and TIMU = Timucuan Ecological and Historical National Preserve) Coastal Scrub Site Maritime Hammock Site 2.68 FCSP 0.92 TIMU 2.88 LTSP 1.01 FCSP 3.13 FCSP 1.47 FCSP 3.3 0 FCSP 1.56 FCSP 3.42 LTSP 1.58 BTSP 3.48 LTSP 2.15 TIMU 3.53 LTSP 2.28 FCSP 4.29 LTSP 2.67 FCSP 4.3 0 LTSP " After hatch year males

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Thrasher 27 Table 2. Vegetation and substrate characteristics of Eastern painted bunting territories in northeast Florida M ean s + SE are reported for species detected at a rate of greater than 4% of the cover on individual transects. X identifies cover types that were present but detected at a rate of less than 4% on an individual transect. B old figures identify the three dominant cover types measured in each habitat. Scientific Name Abbreviation Common Name Coastal Scrub Maritime Hammock LITTER Litter 3.5 + 6.0 29.7 + 23.1 SAND Sand 16.8 + 24.0 1.0 + 4.0 GRASS Grasses 6.1 + 18.7 11.5 + 15.9 Ampelopsis arborea AMAR Peppervine 5.8 + 11.2 A lternathera flavescens ALFL Chaff f lower X Borrichia frutescens BOFR Seaside o xeye X Baccharis halimifolia BAHA Sea m yrtle X X Callicarpa americana CAAM American b eautyberry X Celtis laevigata CELA Southern hackberry .3 + 1.4 C yperus pedunculatus CYPE Beach s tar X Cnidoscolus stimulosus CNST Spurge n ettle X Eupatorium capillifolium EUCA Dog fennel X Ilex opaca ILOP American holly 4.2 + 12.3

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Thrasher 28 Ilex vomitoria ILVO Yaupon holly 6.5 + 10.6 9.1 + 11.3 Juniperus virginiana JUVI Eastern red cedar 7.3 + 17.3 1.2 + 4.0 Myrica cerifera MYCE Wax myrtle 8.7 + 12.8 .3 + 1.3 Opuntia ammophila OPAM Small d evil's tongue X Parthenocissus quinquefolia PAQU Virginia creeper .8 + 3.7 Persia borbonia PEBO Red b ay X Pinus elliottii PIEL Slash p ine X Pinus taeda PITA Loblolly p ine X Quercus falcata QUFA Southern red oak .7 + 3.3 Quercus laurifolia QULA Laurel oak 2.0 + 4.8 Quercus nigra QUNI Water oak 1.0 + 4.5 Quercus virginiana QUVI Virginia l ive oak 2.1 + 5.8 Rhus copallinum RHCO Winged s umac X Rubus argutus RUAR Sawtooth b lackberry X Rubus cuneifolius RUCU Sand b lackberry X Sabal minor SAMI Dwarf palmetto 1.6 + 0.046) Sabal palmetto SAPI Sabal palm .3 + 1.2 2.8 + 5.3 Salicornia perennis SAPE Dwarf g lasswort X Salix caroliniana SACA Carolina willow 3.3 + 12.5 Serenoa repens SERE Saw palmetto 27.1 + 35.3

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Thrasher 29 Sideroxylon tenax SITE Silver buckthorn 3.5 + 8.9 Smilax auriculata SMAU Earleaf greenbrier 22.1 + 18.8 .2 + .9 Smilax tamnoides SMTA Bristly greenbrier 1.7 + 5.3 Spartina alterniflora SPAL Smooth c ordgrass X Spartina patens SPPA Saltmeadow cordgrass 5.7 + 12.3 Toxicodendron radicans TORA Poison i vy X Uniola paniculata UNPA Sea o ats 2.0 + 7.6 Vitis rotundifolia VIRO Muscadine grape 2.2 + 4.7 Yucca aloifolia YUAL Spanish b ayonet X

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Thrasher 30 Figure Legends Fig.1 Study sites in northeast Florida: 1. Fort Clinch State Park (FCSP), 2. Big Talbot Island State Park (BTSP), 3. Little Talbot Island State Park (LTSP) and 4. Timucuan Ecological and Historical Preserve Upper right image shows a territory in maritime hammock at FCSP and lower right image shows a territory in the coastal scrub at LTSP. Figure 2. Mean territory size (ha) with SE, for male painted b untings in coastal scrub (n=9) and salt marsh/ maritime hammock (n=8) habitats, NE Florida, April July 2010. Figure 3. Dominant substrates and vegetation displayed as percent cover in coastal scrub and salt marsh /maritime hammock. The legend corresponds to the graphic beginning from the top in a clockwise manner. Substrate or vegetation which measured less than 4% are displayed together as Other.' Figure 4. Mean number of stems with SE, displayed by height from 0 to 3 m above ground, on territories in c oastal scrub and salt marsh/ maritime hammock. Figure 5. Observed time spent on typical daily behaviors by male Eastern painted buntings on breeding territories in coastal scrub and salt marsh/ maritime habitats. Behaviors are displayed as mean + SE. Figur e 6. Proportion of total vocalizing time that male Eastern painted buntings spent on individual vegetation types See Table 2 for species abbreviations. Plant

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Thrasher 31 species which served as important perches for vocalizing, but were not detected during vegetation sampling include: Baccharis halimifolia (BAHA), Magnolia grandiflora (MAGR), Pinus elliotii (PIEL), oak or pine snags (SNAG), and unknown species (UNK).

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Thrasher 32 Figure 1 # $ %&'()*+,-../0123 2/4+&+5-+&16/&'70123

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Thrasher 33 Figure 2 0 0.5 1 1.5 2 2.5 3 3.5 4 Coastal scrub Maritime hammock Mean territory size (ha) Habitat

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Thrasher 34 Figure 3 22.1 % 16.8 % 8.7 % 6.1% 7.3 % 5.8% 6.5% 5.7% 21.0% Coastal scrub SMAU SAND MYCE GRASS JUVI AMAR ILVO SPPA OTHER 29.7 % 27.1 % 9.1 % 11.5% 4.2 % 18.5% Maritime hammock LITTER SERE ILVO GRASS ILOP OTHER

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Thrasher 35 Figure 4 0 0.5 1 1.5 2 2.5 3 3.5 0-1 1-2 2-3 Mean # of Stems Height (m) Coastal scrub Maritime hmk

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Thrasher 36 Figure 5 0 50 100 150 200 250 300 Flight Forage Preen Vocalize #$%&"'()*"+$&,*-" Behavior Coastal scrub Maritime hmk

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Thrasher 37 Figure 6 0 0.1 0.2 0.3 0.4 0.5 0.6 BAHA CELA JUVI MAGR MYCE PIEL QULA QUVI SACA SNAG UNK Proportion of time observed Plant species Coastal scrub Maritime hmk