Prothonotary Warbler (Cliff Shackelford, Texas Parks and Wildlife Department)

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Prothonotary Warbler (Cliff Shackelford, Texas Parks and Wildlife Department) Prothonotary Warblers (Protonotaria citrea) breed in wet forested areas found throughout much of the low-lying eastern

1 Prothonotary Warbler (Cliff Shackelford, Texas Parks and Wildlife Department) Prothonotary Warblers (Protonotaria citrea) breed in wet forested areas found throughout much of the low-lying eastern United States (Figure 1). Their winter range includes the northwestern Gulf Coast south to northern South America plus a few Caribbean islands (Figure 1), although most individuals winter far south of the Tropic of Cancer (DeGraaf and Rappole 1995). The Partners in Flight (PIF) estimate for the global population of Prothonotary Warblers is 1,800,000 birds with a fairly high combined priority score of 15 (Rich et al. 2004). The WGCPO is estimated to support 5.6% of the global population (Partners in Flight Science Committee 2012). Because of its declining status, this warbler is listed as a Species of Greatest Conservation Need (SGCN) on many state wildlife action plans including the Texas Conservation Action Plan (Texas Parks and Wildlife Department 2011). In the southeastern U.S., Prothonotary Warblers breed in bottomland hardwood forests, riparian woodlands, swamp forests, and other similar forested wetlands and their nests are usually placed over or near water (Petit 1999). Figure 1. Global distribution of Prothonotary Warbler from planetofbirds.com. Orange = summer/breeding, yellow = migration, and blue = winter/non-breeding. According to USGS Breeding Bird Survey data, Prothonotary Warblers have a declining trend in many parts of the country including the West Gulf Coastal Plain/Ouachitas (Figure 2). In the WGCPO, based on data from 78 Breeding Bird Survey routes, the detection index decrease is -

2 3.1 (95% Confidence Interval = -4.3, -1.9). Statewide Breeding Bird Survey detection trends have also decreased since 1966 in Arkansas (-2.2; CI 95% = -3.8, -0.8) and Louisiana (-1.9; CI 95% = -3.0, -0.8), but were non-significant in Oklahoma (2.0; CI 95% = -2.1, 5.9) and Texas (0.96; CI 95% = -0.75, 2.8; Sauer et al. 2014). Within the WGCPO, Regional Concern Score for Prothonotary Warbler is 16 (out of 25 maximum; Panjabi et al. 2012). Moderate threats to their breeding area (TB-r = 3; primarily due to forest loss and fragmentation) and significant regional declines (PT-r = 5) within the WGCPO have resulted in recommendations for management attention to reverse or stabilize the long-term population decline (Partners in Flight Science Committee 2012). In spring, this warbler typically uses a trans-gulf route (Moore et al. 1990) and individuals begin to arrive in the West Gulf Coastal Plain/Ouachita (WGCP/O) region in early April yet peak in numbers in mid-april and stay through August (Wolf et al. 2001). Males establish territories in the latter half of April and females typically arrive 4-7 days later (Brown 2001). This is the only cavity-nesting eastern warbler with nest placement in cavities, crevices, or abandoned woodpecker holes (Dunn and Garrett 1997). This species also uses manmade structures for nesting including a variety of nest-box styles and shapes (Brown 2001). Nests are typically about 1.5 m above the ground (DeGraaf and Rappole 1995). Site-fidelity with breeding habitat appears to be high in this warbler especially when nesting success was high the previous year (Hoover 2003). According to Petit (1999), 71% of males (n = 31) and 29% of females (n = 47) returned to within 50 m of their previous year s nest-site in Tennessee. In one bottomland study, territory size averaged 3.66 acres with the smallest at 1.9 acres (Griscom and Sprunt 1979). Petit (1999; p. 16) lists a few papers in Illinois and Tennessee where densities average approximately 1 pair per 1-2 ha of suitable habitat. Because of extreme habitat specifity, breeding densities can be highly localized throughout their range (Petit 1999). They breed in Texas between mid-april and July with dates for nests with eggs ranging from April 25 to June 4 and the late date for fledging is June 22 (Benson and Arnold 2001).

3 Figure 2. Breeding Bird Survey (BBS) hierarchical population trend for Prothonotary Warbler in the West Gulf Coastal Plain/Ouachita Bird Conservation Region, (Sauer et al. 2014). In a study in eastern Texas, Prothonotary Warblers nested in areas that had fewer trees suggesting a more open stand was preferred (Brown 2001). When given the choice of 4 different manmade nest-boxes, they used ones with smaller (interior) volume over those with larger volume (Brown 2001). Moss makes up the majority of nest-material used by Prothonotary Warblers and large-volume cavities would require more effort to fill than small-volume ones (Brown 2001). If mounting nest-boxes are recommended for land managers, Brown (2001) found that the modified Wood Duck boxes with the warbler loft included were rarely used. Instead, several alternatives were provided including interior dimensions no larger than 10 x 10 cm but no smaller than 7 x 7 cm (Brown 2001). Within-year dispersal distances do not appear to be far for this warbler. According to Petit (1999), a 46-day old juvenile was resighted 7 km from its natal territory while, in another territory, four other juveniles that were days old were found within 200 m of the nest site. Prothonotary Warblers exhibited a trend towards increasing detection with increasing forest corridor width (Hodges and Krementz 1996). A healthy and viable population of Prothonotary Warblers, which consists of at least 500 breeding pairs, would require suitable forested habitat of at least 1,600 ha or 2,800 ha if within an agriculturally-dominated landscape (Hunter et al. 2001). Forests large enough to support large and productive populations of this warbler should be adequate to support source populations of many other species that occur in mature forested wetlands (Hunter et al. 2001); thus, this warbler can be used as an indicator species for such forests.

4 A WGCP/O study in eastern Texas determined that Prothonotary Warblers used more open stands of forested wetlands with a variety of hardwoods including planer tree (Planera aquatica), various ashes (Fraxinus sp.), red maple (Acer rubrum), and various oaks (Quercus sp.) as the more important species (Brown 2001). Land management should include the promotion of healthy forests with various hardwood species, seasonal flooding, and cavity trees. In addition to natural cavities or the lack thereof, warbler-specific nest-boxes could be added over or near the water s edge. Best Management Practices of leaving broad riparian zones along waterways to avoid erosion will benefit this warbler. Altered waterways, especially through the construction of dams which can completely inundate forested wetlands, are one of the main conservation threats to this species. LITERATURE CITED Benson, K.L.P., and K.A. Arnold The Texas Breeding Bird Atlas. Texas A&M University System, College Station and Corpus Christi, TX. (online version posted: 12 July 2001). Brown, R.E Breeding biology, habitat, nest site, and nest box selection by Prothonotary Warblers and other species in eastern Texas. Unpublished M.S. thesis, Stephen F. Austin State University, Nacogdoches, TX. 200 pp. DeGraaf, R.M. and J.H. Rappole Neotropical Migratory Birds: Natural History, Distribution, and Population Change. Comstock/Cornell Press, Ithaca, NY. 676 pp. Dunn, J.L. and K.L. Garrett A Field Guide to the Warblers of North America. Houghton Mifflin Company, Boston. 656 pp. Griscom, L. and A. Sprunt, Jr The Warblers of America. Doubleday and Co., Inc., NY. 302 pp. Hodges, M.F., Jr. and D.G. Krementz Neotropical Migratory Breeding Bird Communities in Riparian Forests of Different Widths along the Altamaha River, Georgia. Wilson Bull. 108: Hoover, J.P Decision rules for site fidelity in a migratory bird, the Prothonotary Warbler. Ecology 84(2): Hunter, W.C., D.N. Pashley, J.G. Dickson, and P.B. Hamel Bird Communities of Southern Forests. In: J.G. Dickson (ed.), Wildlife of Southern Forests: Habitat and Management, pp Hancock House, WA. Moore, F., P. Kerlinger, and T.R. Simons Stopover on a Gulf coast barrier island by spring trans-gulf migrants. Wilson Bull. 102(3):

5 Panjabi, A. O., P. J. Blancher, R. Dettmers, and K. V. Rosenberg, Version Partners in Flight Technical Series No. 3. Rocky Mountain Bird Observatory website: Partners in Flight Science Committee Species Assessment Database, version Available at: Accessed on 10 July Petit, L.J Prothonotary Warbler (Protonotaria citrea). In The Birds of North America, No. 408 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA. Rich, T.D., C.J. Beardmore, H. Berlanga, P.J. Blancher, M.S. W. Bradstreet, G.S. Butcher, D.W. Demarest, E.H. Dunn, W.C. Hunter, E.E. Iñigo-Elias, J.A. Kennedy, A.M. Martell, A.O. Panjabi, D.N. Pashley, K.V. Rosenberg, C.M. Rustay, J.S. Wendt, T.C. Will Partners in Flight North American Landbird Conservation Plan. Cornell Lab of Ornithology. Ithaca, NY. 84 pp. Sauer, J.R., J.E. Hines, J.E. Fallon, K.L. Pardieck, D.J. Ziolkowski, Jr., and W.A. Link The North American Breeding Bird Survey, Results and Analysis Version USGS Patuxent Wildlife Research Center, Laurel, MD. Accessed online at: <9 July 2014>. Texas Parks and Wildlife Department Texas Conservation Action Plan. Online version: Wolf, D.E., C.E. Shackelford, G.G. Luneau, and C.D. Fisher Birds of the Pineywoods of Eastern Texas: A Field Checklist. Texas Parks and Wildlife PWD BK W pp.

Notes on a Breeding Population of Red-headed Woodpeckers in New York State. Jacob L. Berl and John W. Edwards

Notes on a Breeding Population of Red-headed Woodpeckers in New York State Jacob L. Berl and John W. Edwards Division of Forestry and Natural Resources, West Virginia University Morgantown, WV 26505 The