Northeastern Naturalist 658 W.J. Berry, S.E. Reinert, M.E. Gallagher, S.M. Lussier, and E. Walsh 22001155 NORTHEASTERN NATURALIST 2V2(o4l). :2625,8 N–6o7. 14 Population Status of the Seaside Sparrow in Rhode Island: A 25-Year Assessment Walter J. Berry1,*, Steven E. Reinert2, Meghan E. Gallagher1,3, Suzanne M. Lussier1 , and Eric Walsh1 Abstract - To assess long-term changes in the population status of breeding Ammodramus maritimus (Seaside Sparrow) in Rhode Island, we repeated surveys conducted in 1982 by Stoll and Golet (1983). In June and July of 2007 and 2008, we surveyed 19 of Rhode Island’s largest salt marshes. Seaside Sparrow abundance had declined at 9 of 11 marshes where the species was present in 1982, and we detected no sparrows at 4 smaller (<20 ha) marshes where they were present in 1982. Seaside Sparrow abundance increased at 3 marshes, including 1 at which the birds were not detected in 1982. We used aerial photographs to quantify changes in marsh size and human development within 150-m and 1-km buffers surrounding each marsh. From 1981 to 2008, the overall average number of structures within the 150-m and 1-km buffers increased by 37% and 66%, respectively. Concomitantly, salt-marsh area decreased by an overall average of 11%. Seaside Sparrow abundance was related to marsh size, but our analyses did not detect a statistical relationship of landscape or habitat-loss variables with the decline in sparrows. The Seaside Sparrow is currently classified as a species of concern in Rhode Island. However, given the population decline we documented, and the impending threat to salt-marsh habitats imposed by rising sea levels, we suggest that the classification be reassessed now and periodically in the future, and that monitoring efforts for the species be continued. Introduction There is increasing concern over the loss and degradation of salt-marsh habitat due to accelerated rates of sea-level rise associated with anthropogenic climate change (Dahl 2011, Donnelly and Bertness 2001, Stouffer et al. 2013). Ornithologists suggest that sea level is the principal threat to salt-marsh nesting passerines over the next century (Bayard and Elphick 2011, Erwin et al. 2006). Shriver and Gibbs (2004) estimated that current sea-level rise projections dramatically reduce the probability of Ammodramus maritimus Wilson (Seaside Sparrow) population persistence to the year 2100. The loss of the Seaside Sparrow’s tidal habitats in the US coastal zone has proceeded at an accelerated pace, due principally to the draining and filling of tidal marshes for development, and the impoundment of tidal marshes for water management (Post and Greenlaw 2009, Robbins 1983, Walters et al. 2000). Indeed, the extirpation of Ammodramus maritimus nigrescens (Ridgway) (Dusky Seaside Sparrow) from Florida’s east coast has been attributed to the drainage and impoundment 1US EPA, 27 Tarzwell Drive, Narragansett, RI 02882. 211 Talcott Street, Barrington, RI 02806. 3Current address - PO Box 712, Wakefield, RI 02880. *Corresponding author - berry.walter@epa.gov. Manuscript Editor: Peter Paton Northeastern Naturalist Vol. 22, No. 4 W.J. Berry, S.E. Reinert, M.E. Gallagher, S.M. Lussier, and E. Walsh 2015 659 of salt marsh habitats (Post and Greenlaw 2009). A number of agencies have classified the Seaside Sparrow as a species of concern (AFWA 2014, Rich et al. 2004, USFWS 2008). The Seaside Sparrow is listed as 1 of 4 priority bird populations in coastal marshes in southeastern New England (Dettmers and Rosenberg 2000), and it is a species of concern in Rhode Island (RIDEM 2006). The Seaside Sparrow breeds from southern Maine to the Rio Grande Valley along the Atlantic and Gulf coasts (Post and Greenlaw 2009). All 8 subspecies are yearround residents, except the northern subspecies (A. m. maritimus Stotz) that nests from Chesapeake Bay to Maine and migrates to wintering grounds that extend from North Carolina to Florida (Post and Greenlaw 2009, Robbins 1983). Several authors (Greenlaw 1992, Lee 1983, Post and Greenlaw 2009) have promoted the Seaside Sparrow as an indicator species for gauging the overall health of salt-marsh communities. To augment our understanding of the current status of Seaside Sparrow populations in Rhode Island, we used surveys conducted in 1982 by Stoll and Golet (1983) to compare to surveys we conducted in 2007 and 2008. Stoll and Golet (1983) attempted to estimate the abundance of all of Rhode Island’s breeding populations of Seaside Sparrows, and to identify factors affecting the distribution of the species in the state. Our objectives were to: (1) quantify changes in the abundance of Seaside Sparrows in the larger salt marshes in Rhode Island from 1982 to 2007, (2) measure salt-marsh habitat loss at each survey site, (3) quantify land-use changes within 150-m and 1-km buffers surrounding each survey site, (4) investigate relationships between salt marsh and land-use changes and Seaside Sparrow abundance, and (5) provide current baseline information of Seaside Sparrow abundance. Methods Study sites In 2007 and 2008, we surveyed 19 salt marshes visited in 1982 by Stoll and Golet (1983; Fig. 1), including all 11 salt marshes (range = 7–63 ha) where they detected Seaside Sparrows. We lacked the resources required to re-survey all marshes sampled by Stoll and Golet (1983); thus, we repeated surveys in the largest 8 (range = 3–80 ha) sites where no Seaside Sparrows were detected in 1982. This rationale was based on the work of Benoit and Askins (2002) in Connecticut, who found that Seaside Sparrows were less likely to inhabit smaller marshes during the breeding season. Salt marshes may form a relatively continuous coastal band, and delineation between marsh patches is not clear in all cases. In order to facilitate the comparison between our study and Stoll and Golet’s (1983), we delineated the boundaries of 19 marshes we surveyed using their exact methods. Survey protocol We followed the methods of Stoll and Golet (1983) based on discussions with the junior author (F. Golet, pers. comm.) and personal experience (F. Golet and S. Reinert were observers in both the original study and our study). We visited each marsh twice annually between 1 June and 14 July, and conducted surveys between dawn and 9 AM. There was no time limit for the area search. Observers walked a Northeastern Naturalist 660 W.J. Berry, S.E. Reinert, M.E. Gallagher, S.M. Lussier, and E. Walsh 2015 Vol. 22, No. 4 sufficient number of transects to search within ~50 m of every point on each marsh. We made our observations during all tidal stages, although flood tides were necessarily avoided. Observers recorded all Seaside Sparrows detected visually or by song, but did not count birds detected flying over the marsh that did not land within it. Observers plotted the location of each Seaside Sparrow encountered using consecutive ID numbers on hard-copy maps, and cross-referenced the location-ID to notes on behavior and habitat. Observers only recorded birds in one direction as they walked through an area. Observers attempted to minimize double-counting individuals during surveys based on visual and auditory cues. All observers were experienced birders; each was issued a packet containing the protocol, datasheets, aerial photographs, and maps of their sites. GIS methods To quantify changes in marsh area and amount of development between survey years, we used available aerial photography from 1981 and 2008 and digitized the study marshes. We geo-referenced relevant 1981 digital aerial photography (1:50,000) with 2008 10-cm spatial resolution E911 digital color ortho-photography (RIGIS 2011). To adjust for error associated with comparing habitat delineations from imagery with differing spatial resolution, we established a minimum mapping unit of 0.2 ha Figure 1. Location of 19 study sites surveyed for Seaside Sparrows in Rhode Island in 1982, 2007, and 2008. Full site names are provided in Table 1. Northeastern Naturalist Vol. 22, No. 4 W.J. Berry, S.E. Reinert, M.E. Gallagher, S.M. Lussier, and E. Walsh 2015 661 (a minimum detectable feature of 50-m diameter or 2500 m2 based on the 1:50,000 1981 imagery scale) for the 1981 imagery and applied that to the delineations created from the 2008 imagery. We could not delineate the QP and BM sites with confidence on the 1981 photographs because of a white-wash glare that covered most of the images. We used development as a measure of potential anthropogenic impacts on sparrows. We quantified development as the number of structures (residential, commercial, and municipal buildings) within 150 m and 1 km from the marsh edge (Johnston et al. 2002). To quantify the surrounding development for 2008, we used the E911 Sites database available from RIGIS (2011). Statistical analyses F.C. Golet (pers. comm.) made available to us the raw 1982 Seaside Sparrow count-data which was summarized in Stoll and Golet (1983). For each site, we used the maximum of the 2 counts of Seaside Sparrows from 2007 and 2008 to compare to the maximum count recorded for each site in 1982. We evaluated the change in Seaside Sparrow counts among all years (1982, 2007, and 2008) using a 2-sided non-parametric sign test. We used P < 0.05 as the criterion for statistical significance. We analyzed each of the 2007 and 2008 data separately to eliminate a possible bias resulting from comparing the 4 surveys in 2007–2008 to 2 surveys in 1982. We used the modified Simberloff and Gotelli (1984) equation presented in Benoit and Askins (2002) to evaluate the probability that the smallest marsh where a Seaside Sparrow was detected was larger than expected by chance. We considered P < 0.05 evidence that, among the marshes sampled, Seaside Sparrows were selecting against the smaller ones. We hypothesized that change in Seaside Sparrow abundance might be sensitive to a decrease in marsh area or anthropogenic development. To evaluate land-use changes at our 19 study sites, we used multiple linear regression and Akaike’s information criteria approach for model development and assessment (Burnham and Anderson 2002). We developed a general global model (the most complex model of the set of plausible models) and fitted models using maximum likelihood estimation to explore associations of percent change in Seaside Sparrow abundance (response variable) between 1982 and 2007, with percent change in marsh size and the change in building density within 150-m and 1-km zones surrounding each marsh as explanatory variables. We included only marshes where Seaside Sparrows were detected in 1982 and excluded 1 marsh because we were unable to determine its size in 1982 (n = 10). Our global model was: % Sparrow Abundance Change ≈ % marsh area change (%mac) + change in structure density 150 m (csd150) + change in structure density 1 km (CSD1) We employed Akaike’s information criterion corrected for small sample size (AICc) to evaluate the relative strength of competing plausible models (Burnham and Anderson 2002). Models with ΔAICc < 2 were considered plausible models. We ran all regression analyses using SAS v. 9.3 (SAS Institute Inc. 2011). We used Northeastern Naturalist 662 W.J. Berry, S.E. Reinert, M.E. Gallagher, S.M. Lussier, and E. Walsh 2015 Vol. 22, No. 4 R statistical software version 2.8.0 (R Development Core Team 2013) to run all other analyses. Results Seaside Sparrow abundance decreased at 9 of 11 marshes where the species was detected in 1982; it decreased overall by 41% from 1982 to 2007, and by 31% from 1982 to 2008 (Table 1). During 2007/08, we detected no Seaside Sparrows at 4 marshes (all <20 ha) in which they were present in 1982; however, 1 or 2 birds at 3 of those 4 sites were recorded in 1982 (Table 1). In 2007/2008, we observed Seaside Sparrows at 1 of the 7 marshes (SEA) where they were not detected in 1982. Seaside Sparrow abundance increased between 1982 and 2007/2008 at 2 marshes (BHC and EB; Table 1).There were no statistically significant differences in Seaside Sparrow numbers between 1982 and 2007, 1982 and 2008, or 2007 and 2008 (2-sided nonparametric sign test, P = 0.065, P = 0.065, and P = 0.45, respectively). In 1982, Table 1. Abundance of Seaside Sparrows in 19 salt marshes in Rhode Island. Number of singing males given in parentheses following maximum count values. Maximum count Marsh size (ha) CodeA SiteB Town 1982 2007 2008 1981 2008 SEA Seapowet Tiverton 0 (0) 3 (3) NAC 80.1 71.6 BHC Bluff Hill Cove Narragansett 1 (0) 1 (1) 6 (5) 60.7 55 EB East Beach Charlestown 22 (5) 27 (16)D 31(10) 62.7 54.6 WIN Winnapaug Westerly 8 (4) 4 (1) 2 (1)D 60.7 44.5 HAC Hundred-Acre Cove Barrington 33 (18)D 15 (6) 19 (12) 43.7 39.8 PP Potters Pond South Kingstown 5 (1) 1 (0) 0 (0) 38.8 34.4 CB Charlestown Beach Charlestown 7 (4) 2 (1) 3 (2) 33.6 31 QUN Quonochontaug Charlestown 14 (12) 5 (3) 7 (2) 28.3 22.3 MM Marsh Meadows Jamestown 0 (0) 0 (0) 0 (0) 22.7 20.6 PRW Palmer River, West Barrington 4 (0)D 0 (0) 0 (0) 17.8 17.5 CWR Chafee Wildlife Refuge Narragansett 0 (0) 0 (0) 0 (0) 17.4 17 POT Potowomut Warwick 2 (1) 0 (0) 0 (0) 14.6 13.8 TB Third Beach Middletown 0 (0) 0 (0) 0 (0) 12.9 12.9 PRE Palmer River, East Warren 0 (0) 0 (0) 0 (0) 12.5 12.1 RP Rumstick Point Barrington 1 (0) 0 (0) 0 (0) 11.3 11 FH Fox Hill Jamestown 0 (0) 0 (0) 0 (0) 10.1 9.5 QP Quicksand Pond Little Compton 1 (0)D 0 (0) 0 (0) N/AE 6.9 KR Kickemuit River Warren 0 (0) 0 (0) 0 (0) 6.1 5.9 BM Briggs Marsh Little Compton 0 (0) 0 (0) 0 (0) N/AE 3.2 Total 98 (45) 58 (31) 68 (32) 534.0 473.0F ASite-location codes used in Figure 1, and full site names are provided in Table 1. BSalt marsh sites listed in descending order of size in 2008. CNot available. Sparrows at Seapowet were not counted in 2008. A survey performed in 2009 found 3 total birds and 3 singing males. DOnly one visit made to this site in this year. ENot available. Unable to accurately delineate marsh area for 1981 due to reflection of sun causing white-wash distortion on the photograph. FDoes not include QP or BR. Northeastern Naturalist Vol. 22, No. 4 W.J. Berry, S.E. Reinert, M.E. Gallagher, S.M. Lussier, and E. Walsh 2015 663 counts of 4 or more singing male Seaside Sparrows were recorded at 5 marshes, vs. only 3 marshes in 2007/08. In 2007/08, we did not detect Seaside Sparrows on marshes <22 ha (n = 12); all of the 8 larger marshes (which had Seaside Sparrows in 1982) had at least 1 detection during the 2 years (Fig. 2, Table 1). This tendency for the species to select larger marshes in 2007/08 was supported by the Simberloff-Gotelli test, which indicated that the observed minimum-habitat area inhabited by Seaside Sparrows was larger than expected by chance (2007: P = 0.0; 2008: P = 0.0). This result differed from 1982, when 4 marshes ranging in size from 7–18 ha were occupied by between 1 and 4 Seaside Sparrows, and the Simberloff-Gotelli test indicated that birds did not select against small marshes (1982: P = 0.16). Overall, salt-marsh area decreased by 11% across the 17 sites for which it was possible to delineate the marsh using the 1981 imagery (Table 1). There was an overall increase in structures of 37% within the 150-m buffer, and of 66% within the 1-km buffer between 1981 and 2008 (Appendix 1). The explanatory variables did not adequately explain the changes in Seaside Sparrow abundance between 1982 and 2007 or 2008 (Table 2, Fig. 3). The same 3 models (%MAC, CSD150, and CSD1) are viable alternative explanations (ΔAICc < 2) for percent change in Seaside Sparrow abundance between 1982 and 2007 or 2008. However, all 3 models for both periods had low ωi values and relatively high likelihoods (Table 2). There was more support for the %MAC model in 2007 compared to the alternative models (CSD150 and CSD1), but this relationship was marginal and weakened the following year (Tables 1, 2). Further, the top models for both periods did not explain the change in Seaside Sparrow abundance (adjusted r2 values ≤ 0.05). Table 2. Results from the multiple linear regression analysis of Seaside Sparrow abundance in 10 Rhode Island salt marshes for 2007 and 2008. Statistics from the information-theoretic approach (AICc) to model selection are presented. CSD150 and CSD1 = change in structure density within 150- m and 1-km buffer around a marsh, respectively; %MAC= percent change of marsh area. Model K AICc R2 ΔAICc Model likelihood ωi 2007 CSD150 2 17.11 0.17 0.00 1.00 0.33 CSD150 2 15.78 0.05 1.33 0.51 0.17 %MAC 2 15.57 0.03 1.54 0.46 0.15 %MAC + CSD150 3 15.05 0.18 2.06 0.36 0.12 CSD150 = CSD1 3 14.90 0.17 2.22 0.33 0.11 %MAC + CSD1 3 13.68 0.06 3.43 0.18 0.06 %MAC + CSD150 + SD1 4 13.43 0.23 3.68 0.16 0.05 2008 CSD15 2 14.98 0.03 0.00 1.00 0.25 CSD15 2 15.05 0.03 0.06 0.97 0.25 %MAC 2 15.32 0.00 0.33 0.85 0.22 %MAC + CSD150 3 17.10 0.04 2.12 0.35 0.09 CSD150 = CSD1 3 17.20 0.03 2.22 0.33 0.08 %MAC + CSD1 3 17.21 0.03 2.23 0.33 0.08 %MAC + CSD150 + SD1 4 19.39 0.05 4.41 0.11 0.03 Northeastern Naturalist 664 W.J. Berry, S.E. Reinert, M.E. Gallagher, S.M. Lussier, and E. Walsh 2015 Vol. 22, No. 4 Figure 2. Maximum number of Seaside Sparrows detected in salt marshes in 1982 relative to marsh area (ha) measured from 1981 photography (A); in 2007, relative to marsh area (ha) measured from 2008 photography (B); and in 2008, relative to marsh area (ha) measured from 2008 photography (C). Briggs Marsh and Quicksand Pond were plotted with area values from 2008 because their areas could not be delineated from 1981 aerials. Northeastern Naturalist Vol. 22, No. 4 W.J. Berry, S.E. Reinert, M.E. Gallagher, S.M. Lussier, and E. Walsh 2015 665 Figure 3. Percent change in the abundance of Seaside Sparrows surveyed per marsh site in 1982 and 2007 relative to the change in marsh area between 1981 and 2008 (A). Quicksand Pond was omitted because marsh area could not be delineated from 1981 aerials. Percent change in sparrow abundance compared to the change in structure density within a 150-m (B), and 1-km buffer (C), between 1981 and 2007. Marshes with no sparrows detected in both 1982 and 2007 were excluded. Northeastern Naturalist 666 W.J. Berry, S.E. Reinert, M.E. Gallagher, S.M. Lussier, and E. Walsh 2015 Vol. 22, No. 4 Discussion We documented a decline in the abundance of Seaside Sparrows at most of the salt marshes we studied during this study. Our research did not show a relationship between changes in Seaside Sparrow numbers at our sites and the change in structure density in the areas around the marsh, or to changes in marsh area. Another possible explanation for diminishing numbers of Seaside Sparrows on some Rhode Island marshes is a shift in habitat composition that does not favor the species. Breeding-ecology studies conducted in southeastern New England have documented an association between breeding Seaside Sparrows and patches of medium-height Spartina alterniflora Loisel. (Smooth Cordgrass) within which they place their nests (DeRagon 1988, Marshall and Reinert 1990, Reinert and Mello 1995), and Stoll and Golet (1983) found nesting Seaside Sparrows nearly exclusively in these habitats. The invasion of Phragmites australis (Cav.) Trin. ex Steud. (Common Reed) into southeastern New England estuaries has diminished the area of both Smooth Cordgrass and Spartina patens (Aiton) Muhl. (Saltmeadow Cordgrass) habitats on some salt marshes (Benoit and Askins 2002, Paxton 2007, Tiner et al. 2004), and surveys conducted in Connecticut salt marshes during the breeding seasons of 1995 and 1996 by Benoit and Askins (1999) determined that Seaside Sparrows were conspicuously absent from salt marshes on which Common Reed cover had reached or exceeded 50%. Although we do not have data on changes in graminoid cover types on the marshes we surveyed, Common Reed encroachment was clearly occurring on many of them (Charlestown Beach, Potters Pond, Third Beach, Briggs Marsh, and Quicksand Pond had >20% Common Reed cover; Nightingale 2011), and such encroachments may well have contributed to diminished habitat availability for, and thus abundance of, breeding Seaside Sparrows (Paxton 2007). Perhaps the greatest risk to the Seaside Sparrow in the decades ahead stems from loss of salt-marsh breeding habitat due to global climate change. Sea-level rise has accelerated in recent years (Boon 2012), and the flooding of marshes is the inevitable result (Dahl 2011, Shriver and Gibbs 2004). Based on analyses of long-term marsh-core data, rates of surface-marsh flooding, and short-term surface-elevation measures, Erwin et al. (2006) concluded that looking forward 50–100 years, the reversion of marsh-island complexes to open water due to accelerated sea-level rise would dramatically reduce nesting habitat for salt-marsh specialist species such as the Seaside Sparrow. Shriver and Gibbs (2004) assessed the viability of Seaside Sparrow populations in Connecticut in response to sea-level rise scenarios of 50 cm and 100 cm, and determined that both scenarios would dramatically diminish and/or alter saltmarsh habitats and reduce the probability of Seaside Sparrow population persistence to the year 2100. These vegetation changes are already being observed in RI where there is an increase in the short form of Smooth Cordgrass and a concomitant decrease in Saltmeadow Cordgrass (Raposa et al., in press). Smith (2014) reported a change from high-marsh to greater low-marsh vegetation cover on Cape Cod. Based on the current incidence of nest-flooding in Connecticut marshes, Bayard and Elphick (2011) assessed impacts of projected sea-level rise scenarios on the Saltmarsh Sparrow, a species that co-occupies mid-Atlantic and New England salt Northeastern Naturalist Vol. 22, No. 4 W.J. Berry, S.E. Reinert, M.E. Gallagher, S.M. Lussier, and E. Walsh 2015 667 marshes with the congeneric Seaside Sparrow. Their results suggested that nesting Saltmarsh Sparrows would be extremely vulnerable to even slight increases in sea level. Over the past 3 decades, the accelerated rate of sea-level rise has emerged as perhaps the principal threat to the habitats of salt-marsh nesting birds in the eastern US, especially given recent projections that sea-level may rise by as much as 2 m by 2100 (Pfeffer et al. 2008, Rahmstorf 2007). The above-mentioned effects of Common Reed invasion and sea-level rise on salt-marsh habitats may have even greater implications for Seaside Sparrows given their preference for relatively large marsh tracts for breeding sites. Our data suggested an avoidance of small marshes by Seaside Sparrows during 2007/2008, and this finding was consistent with those of Benoit and Askins (2002) in Connecticut where they found that breeding Seaside Sparrows settled in only the largest marshes. Currently, the conservation classification of the Seaside Sparrow in Rhode Island is “concern” (RIDEM 2006). Species that are at the next higher level of state protection, “threatened”, are described as, “… native species that are likely to become State endangered in the future if current trends in habitat loss or other detrimental factors remain unchanged.” In general, taxa classified as threatened in RI have 3–5 known or estimated populations, or are especially vulnerable to habitat loss (RIDEM 2006). Although between-year differences were not statistically significant, our data exhibited a pattern of Seaside Sparrow population decline in Rhode Island between 1982 and 2007/08. Two findings warrant attention: (1) Seaside Sparrow abundance decreased on 9 of 11 marshes where birds were found in 1982 by an average of 41% from 1982 to 2007 and 31% from 1982 to 2008; and (2) singing male birds—indicators of actively breeding populations—were infrequent during both periods. Four or more singing males were observed during a single survey on only 5 marshes (n = 18, 12, 5, 4, and 4 singing males) in 1982 and 3 marshes (n = 16, 12, and 5 singing males) in 2007/2008. In light of these findings, the loss of salt-marsh habitat documented at our study sites over a quarter-century, and the threats to estuarine biota posed by rising sea levels as described above, it would seem prudent to continue monitoring the population and to reexamine the State conservation status of the species presently and periodically into the future. Acknowledgments We thank P. Paton and C. Elphick for their assistance with experimental design. S. Paton and E. King helped with access to several US Fish and Wildlife Service properties. We thank J. Heltshe for his statistical guidance. A. Kuhn helped with statistics and modeling. M. Charpentier helped with GIS. B. Sherman, E. Dettmann, A. Smith, E. Blomberg, P. Capobianco, L. Carberry, R. Emerson, R. McKinney, F. Golet, T. Gleason, W. Munns, K. Raposa, C. Trocki, M. Tucker, L. Vandeveer, K. Winiarski, K. McKeton, and C. Powell collected sparrow-count data without which this study could not have been completed. T. Auer, J. Grear, R. McKinney, and P. Paton commented on earlier versions of the manuscript. Finally, we would like to thank F. Golet for maps, data, and sage advice. Without his cooperation and guidance, this project would not have been possible. Although the research described in this article has been funded wholly by the US Environmental Protection Agency, it has not been subjected to internal review, and therefore, it does not necessarily reflect the views of Northeastern Naturalist 668 W.J. Berry, S.E. Reinert, M.E. Gallagher, S.M. Lussier, and E. Walsh 2015 Vol. 22, No. 4 the Agency. This is contribution number ORD-008919 of the Atlantic Ecology Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, US Environmental Protection Agency. Literature Cited Association of Fish and Wildlife Agencies (AFWA). 2014. State wildlife action plans (SWAPs) Available online at http://www.teaming.com/state-wildlife-action-plansswaps. Accessed 19 August 2014. Bayard, T.S., and C.S. Elphick. 2011. Planning for sea-level rise: Quantifying patterns of Saltmarsh Sparrow (Ammodramus caudacutus) nest flooding under current sea-level conditions. Auk 128:393–403. Benoit, L.K., and R.A. Askins. 1999. Impact of the spread of Phragmites on the distribution of birds in Connecticut marshes. Wetlands 19:194–208. Benoit, L.K., and R.A. Askins. 2002. Relationship between habitat area and the distribution of tidal- marsh birds. Wilson Bulletin 114:314–323. Boon, J.D. 2012. Evidence of sea-level acceleration at US and Canadian tide stations, Atlantic Coast, North America. Journal of Coastal Research 28:1437–1445. Burnham, K.P., and D.R. Anderson. 2002. Model Selection and Multimodel Inferences: A Practical Information-Theoretic Approach, 2nd Edition. Springer, New York, NY. 488 pp. Dahl, T.E. 2011. Status and trends of wetlands in the conterminous United States 2004 to 2009. US Department of the Interior; Fish and Wildlife Service, Washington, DC. 108 pp. DeRagon, W.R. 1988. Breeding ecology of Seaside and Sharp-tailed Sparrows in Rhode Island salt marshes. M.Sc. Thesis. University of Rhode Island, Kingston, RI. 95 pp. Dettmers, R., and K. Rosenberg. 2000. Partners in Flight landbird conservation plan. Physiographic area 9: Southern New England. Northeast Partners In Flight Working Group and American Bird Conservancy, The Plains, VA. 48 pp. Donnelly, J.P., and M.D. Bertness. 2001. Rapid shoreward encroachment of Salt Marsh Cordgrass in response to accelerated sea-level rise. Proceedings of the National Academy of Sciences of the United States of America 98:14,218–14,223. Erwin, R.M., D.R. Cahoon, D.J. Prosser, G.M. Sanders, and P. Hensel. 2006. Surfaceelevation dynamics in vegetated Spartina marshes versus unvegetated tidal ponds along the mid-Atlantic coast, USA, with implications to waterbirds. Estuaries and Coasts 29:96–106. Greenlaw, J.S. 1992. Seaside Sparrow, Ammodramus maritimus. Pp. 211–234, In K.J. Schneider and D.M. Pence (Eds.). Migratory Non-game Birds of Management Concern in the Northeast. USDI Fish and Wildlife Service, Region 5, Newton Corner, MA. 400 pp. Johnston, R.J., G. Magnusson, M.J. Mazzotta, and J.J. Opaluch. 2002. Combining economic and ecological indicators to prioritize salt-marsh restoration actions. American Journal of Agricultural Economics 84:1362–1370. Lee, D.S. 1983. Introduction. Pp. 1–2, In T.L. Quay Jr., D.S. Lee, E.F. Potter, and C.S. Robbins (Eds.). The Seaside Sparrow: Its Biology and Management. Occasional Papers of the North Carolina Biological Survey 1983–1985. North Carolina State Museum of Natural History, Raleigh, NC. 174 pp. Marshall, R.M., and S.E. Reinert. 1990. Breeding ecology of Seaside Sparrows in a Massachusetts salt marsh. Wilson Bulletin 102:501–513. Northeastern Naturalist Vol. 22, No. 4 W.J. Berry, S.E. Reinert, M.E. Gallagher, S.M. Lussier, and E. Walsh 2015 669 Nightingale, M. 2011. Mapping vegetation composition on Rhode Island coastal salt marshes for habitat quality assessment. M.Sc. Thesis. University of Rhode Island, Kingston, RI. 54 pp. Paxton, B.J. 2007. Potential impact of Common Reed expansion on threatened high-marsh bird communities on the seaside: Breeding bird surveys of selected high-marsh patches. Center for Conservation Biology Technical Report Series, CCBTR-07-03. College of William and Mary, Williamsburg, VA. 19 pp. Pfeffer, W., J. Harper, and S. O’Neel. 2008. Kinematic constraints on glacier contributions to 21st-century sea-level rise. Science 321:1340–1343. Post, W., and J.S. Greenlaw. 2009. Seaside Sparrow (Ammodramus maritimus). Number 127, In A. Poole (Ed.). The Birds of North America Online. Cornell Lab of Ornithology, Ithaca, NY. Available online at http://bna.birds.cornell.edu/bna/species/127. Accessed 3 March 2010. R Development Core Team. 2013. R: A language and environment for statistical computing, reference index version 2.8.0. R Foundation for Statistical Computing, Vienna, Austria. ISBN 3-900051-07-0. Available online at http://www.R-project.org. Accessed 15 January 2015. Rahmstorf, S. 2007. A semi-empirical approach to projecting future sea-level rise. Science 315:368–370. Raposa, K.B., R.L. Weber, M. Cole Ekberg, and W. Ferguson. In press. Vegetation dynamics in Rhode Island salt marshes during a period of accelerating sea-level rise and extreme sea-level events. Estuaries and Coasts. Reinert, S.E., and M.J. Mello. 1995. Avian-community structure and habitat use in a southern New England estuary. Wetlands 15:9–19. Rich, T.D., C.J. Beardmore, H. Berlanga, P.J. Blancher, M.S.W. Bradstreet, G.S.Butcher, D. Demarest, E.H. Dunn, W.C. Hunter, E. Iñigo-Elias, J.A. Kennedy, A. Martell, A. Panjabi, D.N. Pashley, K.V. Rosenberg, C. Rustay, S. Wendt, and T. Will. 2004. Partners in Flight North American landbird conservation plan. Cornell Lab of Ornithology, Ithaca, NY. Available online at http://www.partnersinflight.org/cont_plan/. Accessed March 2005. Rhode Island Department of Environmental Management (RIDEM). 2006. Rare native animals of Rhode Island: Revised March 2006. Available online at http://www.dem.ri.gov/ programs/bnatres/fishwild/pdf/species2.pdf. Accessed 30 April 2011. Rhode Island Geographical Information System. (RIGIS). 2011. RIGIS data distribution system. Environmental Data Center, University of Rhode Island, Kingston, RI. Available online at http://www.edc.uri.edu/rigis. Accessed 7 February 2011. Robbins, C.S. 1983. Distribution and migration of the Seaside Sparrow. Pp. 31–44, In T.L. Quay Jr., D.S. Lee, E.F. Potter, and C.S. Robbins (Eds.). The Seaside Sparrow: Its Biology and Management. Occasional Papers of the North Carolina Biological Survey 1983–1985. North Carolina State Museum of Natural History, Raleigh, NC. 174 pp. SAS Institute Inc. 2011. SAS® 9.3 System options: Reference, 2nd Edition. SAS Institute Inc., Cary, NC. Shriver, W.G., and J.P. Gibbs. 2004. Seaside Sparrows (Ammodramus maritimus) in Connecticut. Pp. 397–409, In H.R. Akcakaya, M.A. Burgman, O. Kindvall, C.C. Wood, P. SjögrenGulve, J.S. Hatfield, and M.A. McCarthy (Eds.). Species Conservation and Management: Case Studies. Oxford University Press, New York, NY. 533 pp. Simberloff, D., and N. Gotelli. 1984. Effects of insularization on plant-species richness in the prairie–forest ecotone. Biological Conservation 29:27–46. Smith, S.M. 2014. Vegetation change in salt marshes of Cape Cod National Seashore (Massachusetts, USA) between 1984 and 2013. Wetlands 35:127–136. Northeastern Naturalist 670 W.J. Berry, S.E. Reinert, M.E. Gallagher, S.M. Lussier, and E. Walsh 2015 Vol. 22, No. 4 Stoll, M.J., and F.C. Golet. 1983. Status of the Seaside Sparrow in Rhode Island. Audubon Society Report of Rhode Island 17:60–61. Stouffer, P.C., S. Taylor, S. Woltmann, and C.M. Burns. 2013. Staying alive on the edge of the earth: Response of Seaside Sparrows (Ammodrammus maritimus) to salt marsh inundation, with implications for storms, spills, and climate change. Pp. 82–93, In T.F. Shupe and M.S. Bowen (Eds.). Proceedings of 2013 Louisiana Natural Resources Symposium, Louisiana State University, Baton Rouge, LA. 115 pp. Tiner, R.W., I.J. Huber, T. Nuerminger, and A.L. Mandeville. 2004. Coastal wetland trends in the Narragansett Bay Estuary during the 20th century. National Wetlands Inventory Cooperative Interagency Report. US Fish and Wildlife Service, Northeast Region, in cooperation with the University of Massachusetts-Amherst and the University of Rhode Island, Hadley, MA. 37 pp. plus appendices. US Fish and Wildlife Service (USFWS). 2008. Birds of Conservation Concern 2008. Division of Migratory Bird Management, Arlington, VA. 85 pp. Walters, J.R., S.R. Beissinger, J.W. Fitzpatrick, R. Greenberg, J.D. Nichols, H.R. Pulliam, and D.W. Winkler. 2000. The AOU Conservation Committee review of the biology, status, and management of Cape Sable Seaside Sparrows: Final report. The Auk 117:1093–1115. Northeastern Naturalist Vol. 22, No. 4 W.J. Berry, S.E. Reinert, M.E. Gallagher, S.M. Lussier, and E. Walsh 2015 671 Appendix 1. Changes in the number of structures within 2 buffer zones at 19 salt marshes in Rhode Island from 1981 to 2008. Site-location codes are those used in Figure 1, and full site names are given in Table 1. Salt marsh sites are listed in descending order of marsh size in 2008. Number of structures in Number of structures in 150-m buffer 1-km buffer Code Site 1981 2008 Size (ha) 1981 2008 Size (ha) SEA Seapowet 19 29 183 214 325 896 BHC Bluff Hill Cove 116 160 148 881 1428 788 EB East Beach 0 0 156 92 159 982 WIN Winnapaug 163 213 200 765 1248 1103 HAC Hundred Acre Cove 51 92 167 1507 2523 1251 PP Potters Pond 204 226 145 993 1408 809 CB Charlestown Beach 48 81 121 332 556 718 QUN Quonochontaug 46 68 100 321 505 643 MM Marsh Meadows 3 9 80 384 604 610 PRW Palmer River West 12 19 59 197 347 549 CWR Chafee Wildlife Refuge 4 21 83 323 725 675 POT Potowomut 16 25 63 329 488 574 TB Third Beach 12 10 52 31 42 515 PRE Palmer River East 0 0 59 345 632 528 RP Rumstick Point 21 24 46 85 133 486 FH Fox Hill 2 3 49 53 91 503 QP Quicksand Pond 1 2 58 111 153 572 KR Kickemuit River 0 9 38 618 1317 461 BM Briggs Marsh 25 28 57 208 266 581 Total 743 1019 7789 12,950