Distribution and Habitat Use of King Rails in the Illinois and Upper Mississippi River Valleys

Abstract

The migratory population of the king rail (Rallus elegans) has declined dramatically during the past 40 years, emphasizing the need to identify habitat requirements of this species to help guide conservation efforts. To assess distribution and habitat use of king rails along the Illinois and Upper Mississippi valleys, USA, we conducted repeated call‐broadcast surveys at 83 locations in 2006 and 114 locations in 2007 distributed among 21 study sites. We detected king rails at 12 survey locations in 2006 and 14 locations in 2007, illustrating the limited distribution of king rails in this region. We found king rails concentrated at Clarence Cannon National Wildlife Refuge, an adjacent private Wetlands Reserve program site, and B. K. Leach Conservation Area, which were located in the Mississippi River floodplain in northeast Missouri. Using Program PRESENCE, we estimated detection probabilities and built models to identify habitat covariates that were important in king rail site occupancy. Habitat covariates included percentage of cover by tall (>1 m) and short (>1 m) emergent vegetation, percentage of cover of woody vegetation, and interspersion of water and vegetation (2007 only) within 50 m of the survey location. Detection probability was 0.43 (SE = 0.12) in 2006 and 0.35 (SE = 0.03) in 2007 and was influenced by observer identity and percentage of cover by tall herbaceous vegetation. Site occupancy was 0.11 (SE = 0.04) in 2006 and 0.14 (SE = 0.04) in 2007 and was negatively influenced most by percentage of cover by woody vegetation. In addition, we found that interspersion of vegetation and water was positively related to occupancy in 2007. Thus, nesting king rails used wetlands that were characterized by high water‐vegetation interspersion and little or no cover by woody vegetation. Our results suggest that biologists can improve king rail habitat by implementing management techniques that reduce woody cover and increase vegetation‐water interspersion in wetlands.

Balancing habitat delivery for breeding marsh birds and nonbreeding waterfowl: An integrated waterbird management and monitoring approach at Clarence Cannon National Wildlife Refuge, Missouri

“…This composite management action results in the "hemi-marsh" state and is consistent with findings for wintering waterfowl (Smith and others, 2004) and the evidence that breeding king rails benefit from periodic disturbances to reduce the dominance of perennial vegetation and enhance interspersion (Bolenbaugh and others, 2012;Darrah and Krementz, 2009).…”

“…This is only a starting point-we will improve our decision support tools over time. We will provide copies of King Rail articles by Bolenbaugh et al 2012 andDarrah andKrementz 2009 for your convenience but it is not necessary to consider these articles to complete the data sheet. King Rail occupancy at Clarence Cannon based on available data.…”

Distribution and Habitat Associations of Breeding Secretive Marsh Birds in Louisiana’s Mississippi Alluvial Valley

“…Interestingly, we detected numerous individuals in early spring and many of our sampled wetlands had attributes which would presumably be attractive to these breeding birds (Reid 1989;Meanley 1992;Darrah and Krementz 2009). Budd (2007) also found very low numbers of breeding King Rails in the MAV of Arkansas and our combined results seem to indicate that this species breeds very infrequently in the region.…”

Habitat associations and survey effort for shrubland birds in an urban pine barrens preserve

“…This was the most parameterized (about four sample points per model parameter) of the six models. We also modeled the influence of habitat type (p(HABITAT)), observer identity (p(OBSERVER)), and time of day (p(STARTTIME)) on detection probability, as all of these factors can influence the potential detectability of numerous bird species (Chandler et al, 2009;Darrah and Krementz, 2009;Gonzalo-Turpin et al, 2008;King et al, 2009a,b;Mitchell and Donovan, 2008;Pagano and Arnold, 2009;Ruiz-Gutiérrez et al, 2010;Skirven, 1981). We converted habitat cover and point count start times into standard normal deviates (z-scores) to help facilitate convergence of the numerical optimization algorithm, and modeled observers as categories (observer 1 vs. 2).…”

“…Because detection of animals often varies among habitat types and structural characteristics (Chandler et al, 2009;Chace et al, 2009;Darrah and Krementz, 2009;Gonzalo-Turpin et al, 2008;Mitchell and Donovan, 2008;Ruiz-Gutiérrez et al, 2010), neglecting to correct for detection probability may lead to erroneous conclusions based on a species' detectability in different habitats rather than its actual habitat preferences. Recent bird studies have incorporated an occupancy-detection modeling approach to rigorously test hypotheses about habitat associations (Betts et al, 2008;DeWan et al, 2009;Hennemen and Andersen, 2009;Kroll et al, 2007;Pagano and Arnold, 2009;Richmond et al, 2008), but such analyses have not been done for shrubland birds in pine barrens.…”