Conspecific brood parasitism in the tropics: an experimental investigation of host responses in common moorhens and American purple gallinules

Species occupying a broad latitudinal range may show greater phenotypic plasticity in behavior than species with smaller ranges or more specific habitat requirements. This study investigates for the first time the occurrence of conspecific brood parasitism (CBP) in sympatric tropical populations of the common moorhen (Gallinula chloropus pauxilla Bangs) and the American purple gallinule (Porphyrula martinica L.). CBP occurred in at least 20% (N = 76) of common moorhen nests on the Rio Chagres in Panama. Half (N = 20) of the parasitic eggs were accepted, but 10 were destroyed or ejected from host nests. Introductions of experimental eggs into nests revealed hosts were more likely to accept parasitism later in the host's laying period and during incubation, consistent with expectation of an adaptive response. CBP was not detected in a small sympatric population of American purple gallinules. Members of this population did not eject experimental eggs, suggesting a lack of experience with costly CBP. Contrasting ecological factors help explain why these two species of rail (Family Rallidae) differ in regard to CBP. Purple gallinule territories were sparse, owing to the distribution of preferred habitat. Moorhens flocked outside of the breeding season. They nested more synchronously, at higher densities, and primarily in ephemeral floating vegetation. Further, moorhens suffered a rate of nest loss nearly double that of American purple gallinules, and this increased over the course of the breeding season. Moorhen clutches were larger on average, and more variable in size than those of purple gallinules. Reproductive effort and rate (seasonality) constitute important life history differences between these species that may constrain the evolution of reproductive tactics. Comparing these sympatric populations, and others differing in life-history traits and ecological constraints, highlights the role of risk management in the evolution of CBP

Seasonal home range dynamics and sex di�erences in habitat use in a threatened, coastal marsh bird

A comprehensive understanding of spatiotemporal ecology is needed to develop con- servation strategies for declining species. The king rail (Rallus elegans) is a secretive marsh bird whose range historically extended across the eastern United States. Inland migratory populations have been greatly reduced with most remaining populations inhabiting the coastal margins. Our objectives were to determine the migratory status of breeding king rails on the mid-Atlantic coast and to characterize home range size, seasonal patterns of movement, and habitat use. Using radiotelemetry, we tracked individual king rails among seasons, and established that at least a segment of this breeding population is resident. Mean (±SE) home range size was 19.8 ± 5.0 ha (95% kernel density) or 2.5 ± 0.9 (50% kernel density). We detected seasonal variation and sex differences in home range size and habitat use. In the nonbreeding season, resi- dent male home ranges coincided essentially with their breeding territories. Overwintering males were more likely than females to be found in natural emergent marsh with a greater area of open water. Females tended to have larger home ranges than males during the nonbreeding season. We report for the first time the use of wooded natural marsh by overwintering females. Brood-rearing king rails led their young considerable distances away from their nests (average maximum distance: ~600 ± 200 m) and used both wooded natural and impounded marsh. King rails moved between natural marsh and managed impoundments during all life stages, but the proximity of these habitat types particularly benefitted brood-rearing parents seeking foraging areas with shallower water in proximity to cover. Our results demonstrate the importance of interspersion of habitat types to support resident breeders. Summer draining of impounded wetlands that are seasonally flooded for wintering waterfowl allows regrowth of vegetation and provides additional habitat at a critical time for wading birds

Interclutch variability in egg characteristics in two species of rail: Is maternal identity encoded in eggshell patterns?

© 2022 Johnson, McRae. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Maternal signatures are present in the eggs of some birds, but quantifying interclutch variability within populations remains challenging. Maternal assignment of eggs with distinctive appearances could be used to non-invasively identify renesting females, including hens returning among years, as well as to identify cases of conspecific brood parasitism. We explored whether King Rail (Rallus elegans) eggs with shared maternity could be matched based on eggshell pattern. We used NaturePatternMatch (NPM) software to match egg images taken in the field in conjunction with spatial and temporal data on nests. Since we had only a small number of marked breeders, we analyzed similar clutch images from a study of Eurasian Common Moorhens (Gallinula chloropus chloropus) with color-banded breeders for which parentage at many nests had been verified genetically to validate the method. We ran 66 King Rail clutches (n = 338 eggs) and 58 Common Moorhen clutches (n = 364 eggs) through NPM. We performed non-metric multidimensional scaling and permutational analysis of variance using the best egg match output from NPM. We also explored whether eggs could be grouped by clutch using a combination of egg dimensions and pattern data derived from NPM using linear discriminant analyses. We then scrutinized specific matches returned by NPM for King Rail eggs to determine whether multiple matches between the same clutches might reveal maternity among nests and inform our understanding of female laying behavior. To do this, we ran separate NPM analyses for clutches photographed over several years from two spatially distant parts of the site. With these narrower datasets, we were able to identify four instances where hens likely returned to breed among years, four likely cases of conspecific brood parasitism, and a within-season re-nesting attempt. Thus, the matching output was helpful in identifying congruent egg patterns among clutches when used in conjunction with spatial and temporal data, revealing previously unrecognized site fidelity, within-season movements, and reproductive interference by breeding females. Egg pattern data in combination with nest mapping can be used to inform our understanding of female reproductive effort, success, and longevity in King Rails. These methods may also be applied to other secretive birds and species of conservation concern.ECU ALS PLOS Institutional Account Progra

Seasonal home range dynamics and sex differences in habitat use in a threatened, coastal marsh bird

A comprehensive understanding of spatiotemporal ecology is needed to develop conservation strategies for declining species. The king rail (Rallus elegans) is a secretive marsh bird whose range historically extended across the eastern United States. Inland migratory populations have been greatly reduced with most remaining populations inhabiting the coastal margins. Our objectives were to determine the migratory status of breeding king rails on the mid-Atlantic coast and to characterize home range size, seasonal patterns of movement, and habitat use. Using radiotelemetry, we tracked individual king rails among seasons, and established that at least a segment of this breeding population is resident. Mean (±SE) home range size was 19.8 ± 5.0 ha (95% kernel density) or 2.5 ± 0.9 (50% kernel density). We detected seasonal variation and sex differences in home range size and habitat use. In the nonbreeding season, resident male home ranges coincided essentially with their breeding territories. Overwintering males were more likely than females to be found in natural emergent marsh with a greater area of open water. Females tended to have larger home ranges than males during the nonbreeding season. We report for the first time the use of wooded natural marsh by overwintering females. Brood-rearing king rails led their young considerable distances away from their nests (average maximum distance: ~600 ± 200 m) and used both wooded natural and impounded marsh. King rails moved between natural marsh and managed impoundments during all life stages, but the proximity of these habitat types particularly benefitted brood-rearing parents seeking foraging areas with shallower water in proximity to cover. Our results demonstrate the importance of interspersion of habitat types to support resident breeders. Summer draining of impounded wetlands that are seasonally flooded for wintering waterfowl allows regrowth of vegetation and provides additional habitat at a critical time for wading birds.ECU Open Access Publishing Support Fun

Mapping Habitat Suitability for the Eastern Black Rail throughout its Atlantic Coastal Range Using Maximum Entropy (MaxEnt)

Modeling a species' distribution can be a powerful tool for predicting the location of additional habitat. Identifying suitable habitat is of critical importance for data-deficient species of conservation concern. The Black Rail (Laterallus jamaicensis), a small marsh bird, is listed as globally endangered. We created a habitat suitability model for the eastern subspecies focusing on the Atlantic coastal plain using eBird data contributed by citizen scientists and environmental data from the Esri databank using a maximum entropy model framework. The map generated from the model indicated habitat suitability in areas known for Black Rail occupation and predicted other suitable sites. Environmental factors that best predicted Black Rail presence were flooded areas with shrub and herbaceous vegetation, proximity to water, and flat plains. These environmental associations were congruent with characteristics of high marsh, emphasizing its importance for the species. Black Rails have been found to occupy this habitat type in the coastal part of their range. Habitat association studies conducted in other parts of the species' range that focused on smaller areas and used presence/absence survey data collected via species-targeted callback surveys identified similar habitat characteristics. Our habitat suitability model thus adds to a growing list of studies using distribution data from public databases with significant power to predict occupancy over a landscape scale. The map generated by this model will inform land management decisions and habitat restoration efforts

Characterization of microsatellite loci for a threatened species, the King Rail, Rallus elegans, using a next-generation sequencing protocol

The King Rail Rallus elegans (Audubon) has experienced population declines of 4.6 % per year on average since the 1960s. Wetland loss, most severely affecting inland marshes, has significantly reduced this species\u27 distribution to the coastal margins of its historic range. Polymorphic microsatellite markers were generated by 454 pyrosequencing of genomic DNA from King Rails, and Clapper Rails R. longirostris from Louisiana after AFLP enrichment and barcoding of restriction fragment cut sites across individuals. Of 1,419 microsatellite-containing sequences, 20 hypervariable microsatellite loci with up to 20 different alleles were identified at the alignment stage. We characterized nine loci, tested variability in 45 Atlantic coast King Rail samples, and detected 4-19 alleles per locus. Cross-species amplification revealed variability in the Virginia Rail, R. limicola, and Sora, Porzana carolina. These loci will be useful for studying secretive marsh rails, many of which are threatened or endangered. © 2013 Springer Science+Business Media Dordrecht

Genetic analyses reveal cryptic introgression in secretive marsh bird populations

Hybridization is common in bird populations but can be challenging for management, especially if one of the two parent species is of greater conservation concern than the other. King rails (Rallus elegans) and clapper rails (R. crepitans) are two marsh bird species with similar morphologies, behaviors, and overlapping distributions. The two species are found along a salinity gradient with the king rail in freshwater marshes and the clapper in estuarine marshes. However, this separation is not absolute; they are occasionally sympatric, and there are reports of interbreeding. In Virginia, USA, both king and clapper rails are identified by the state as Species of Greater Conservation Need, although clappers are thought to be more abundant and king rails have a higher priority ranking. We used a mitochondrial DNA marker and 13 diagnostic nuclear single nucleotide polymorphisms (SNPs) to identify species, classify the degree of introgression, and explore the evolutionary history of introgression in two putative clapper rail focal populations along a salinity gradient in coastal Virginia. Genetic analyses revealed cryptic introgression with site‐specific rates of admixture. We identified a pattern of introgression where clapper rail alleles predominate in brackish marshes. These results suggest clapper rails may be displacing king rails in Virginia coastal waterways, most likely as a result of ecological selection. As introgression can result in various outcomes from outbreeding depression to local adaptation, continued monitoring of these populations would allow further exploration of hybrid fitness and inform conservation management

Ursinus College Alumni Journal, August 1967

Exposure \u2767 Ursinus • Viewpoint at commencement time: Means to an end; Toward freedom; Liberal morality; Open-minded attitude; Quality vs. quantity • From the President • What makes Suzy a language dud? • The paradox of urbia: an interview • Negro voices of the city • Springtime was alumni time • Dr. Myers wins alumni award • Dr. Wessel speaks on urbia • Alumni giving climbs in 1967 • Campus clippings: Collegeville area grows; Staigers tour world; Color film; Miss congeniality; New Board members; Placement service; Schultze promoted; Humble gift; Include Ursinus in your will • Sporting scene: Tennis; Baseball; Track • Anatomy of medical school life • Class notebook • Faculty members speak at spring regional meetings • Weddings • Births • In memoriam • Physicians Club meets •https://digitalcommons.ursinus.edu/alumnijournal/1089/thumbnail.jp