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Vasseur, P.L.; Collins, S.A., and Selman, W., 2023. Effects of tropical cyclones and other severe weather events on Reddish Egret (Egretta rufescens) populations in Louisiana, U.S.A. Journal of Coastal Research, 39(6), 1124–1136. Charlotte (North Carolina), ISSN 0749-0208. Tropical cyclones (i.e. tropical depressions, tropical storms, and hurricanes) and other extreme weather events directly impacting Louisiana from 2016–21 were examined to determine their effects on adult Reddish Egrets equipped with satellite transmitters in SE (n = 11) and SW (n = 14) Louisiana. Fourteen tropical cyclones (six hurricanes, five tropical storms, one tropical depression, and two extratropical cyclones) impacted Louisiana during the study, and telemetry data were reviewed immediately on and around (±1 day) the arrival of each storm to monitor any movements and individual survival. As many as nine of 25 (36%) transmittered Reddish Egrets presumably died from the direct impacts of five tropical cyclones; seven of nine mortalities were associated with three major hurricanes. Mortality was presumed based on stationary GPS fixes for multiple days or the termination of data transmission following a storm. All mortalities were presumed, as no carcasses were recovered. Previous telemetry studies reported Reddish Egrets often survived intense tropical cyclones and direct impacts were not appreciable at the population level. Yet, more than one-third of the transmittered birds in the sample population potentially died from storm-related impacts, and the population may have declined drastically, assuming some unmarked individuals also likely died. Because the Reddish Egret is restricted to coastal habitats, the species appears to be particularly vulnerable to tropical cyclone effects. If predictions of increased frequency and intensity of tropical cyclones by the end of this century are accurate, these storms pose a significant threat to Reddish Egret populations. With accelerated loss and degradation to suitable coastal habitats, protection and restoration of key foraging and nesting sites for sensitive species similar to the Reddish Egret are needed in Louisiana and other disturbance-prone areas along the Gulf Coast. [ABSTRACT FROM AUTHOR]

Time–activity budget studies provide valuable insights for better understanding animal behavior relative to spatial and temporal habitat use. We examined a reintroduced, nonmigratory Whooping Crane (Grus americana) population to determine how time–activity budgets change relative to crane age, sex, habitat type, and season. Our study area encompassed natural marshes and working wetlands primarily in southwestern Louisiana. From June 2012 to January 2016, we conducted continuous focal sampling on individuals (n = 27) from the first 4 captive-reared cohorts released in the state. We classified age groups as juveniles, subadults, and adults, and identified 5 main habitat types utilized by cranes in Louisiana: crawfish ponds, rice fields, agricultural levees/farm roads, fallow fields, and natural wetlands. On average, cranes spent approximately 53% of their diurnal time–activity budget foraging. Maintenance/rest (28%), vigilance (12%), locomotion (6%), and other/unknown (2%) behaviors accounted for the remainder of the time observed. Foraging most frequently occurred in fallow fields and crawfish ponds where cranes likely encountered greater invertebrate biomass and density. Cranes tended to spend less time foraging and more time on maintenance as they aged, which could indicate age-dependent differences based on experience on the landscape. Vigilance levels were not significantly affected by age, but males tended to be more vigilant than females. As this young population continues to mature, additional study of breeding pairs and family groups may elucidate other behavioral differences in response to the dynamic habitat conditions in the region. Los estudios de presupuesto de actividades - tiempo dan un punto de visto valioso para entender el comportamiento animal con respecto al uso espacial y temporal del hábitat. Examinamos una población reintroducida no migratoria de grulla Grus americana para determinar cómo cambia el presupuesto actividad- tiempo según la edad y sexo de la grulla, el tipo de hábitat y la estación. Nuestro estudio comprende pantanos naturales y humedales activos principalmente en el sudoeste de Louisiana. De junio del 2012 a enero del 2016, hicimos un muestreo focal continuo de individuos (n=27) de las 4 primeras cohortes criadas en cautiverio liberadas en el estado. Clasificamos los individuos por edad, como juveniles, subadultos y adultos, e identificamos 5 tipos principales de hábitat que usaban las grullas en Louisiana: estanques de langostinos, campos de arroz, diques agrícolas/caminos agrícolas, campos de cultivo en descanso y humedales naturales. En promedio, las grullas gastaron 53% de su presupuesto diario de actividades-tiempo forrajeando. El resto del tiempo observado se repartía entre comportamientos de mantenimiento/descanso (28%), vigilancia (12%), locomoción (6%) y otra/desconocido (2%). El forrajeo más frecuente se observaba en campos de cultivo en descanso y en estanques de langostino donde las grullas posiblemente encontraban mayor densidad y biomasa de invertebrados. Las grullas tendían a pasar menos tiempo forrajeando y más tiempo en mantenimiento conforme envejecían, lo que podría indicar diferencias dependientes de la edad según experiencia en el paisaje. Los niveles de vigilancia no cambiaban significativamente con la edad, pero los machos tendían a ser más vigilantes que las hembras. Conforme la joven población continúa su maduración, estudios adicionales de parejas reproductivas y grupos familiares pueden dilucidar otras diferencias conductuales en respuesta a las condiciones dinámicas del hábitat de las región. Palabras clave: campo de arroz, comportamiento, estanque de langostinos, forrajeo, Gruidae, humedales. [ABSTRACT FROM AUTHOR]

Declines in populations of Passerina ciris (Painted Buntings) have led to their recent classification as a species of conservation concern. As part of a larger study investigating factors associated with nest success in south-central Louisiana during 2010-2011, we monitored a subsample of nests ( n = 14) with video cameras in 2011 to identify nest predators and parasitism events. In addition, we quantified parental activity at the nest to determine if nest attendance and visitation rate during the incubation and nestling stages affected nest success. On average, successful nests were visited less frequently (0.74 ± 0.07 visits/hr) than failed nests (1.04 ± 0.07 visits/hr) during incubation. During the nestling stage, mean nest attendance of successful nests was lower (11.51 ± 1.96 min/hr) compared to failed nests (30.95 ± 3.23 min/hr), and contrary to predictions, mean visitation rate of successful nests (5.46 ± 0.46 visits/hr) was greater than that of failed nests (2.50 ± 0.50 visits/hr). Visitation was positively associated with greater nest concealment, which may have helped mitigate the risk of attracting predators and brood-parasites through increased parental activity. [ABSTRACT FROM AUTHOR]

In temperate regions, the annual pattern of spring onset can be envisioned as a 'green wave' of emerging vegetation that moves across continents from low to high latitudes, signifying increasing food availability for consumers.Many herbivorous migrants 'surf' such resource waves, timing their movements to exploit peak vegetation resources in early spring. Although less well studied at the individual level, secondary consumers such as insectivorous songbirds can track vegetation phenology during migration as well.We hypothesized that four species of ground‐foraging songbirds in eastern North America—two warblers and two thrushes—time their spring migrations to coincide with later phases of vegetation phenology, corresponding to increased arthropod prey, and predicted they would match their migration rate to the green wave but trail behind it rather than surfing its leading edge.We further hypothesized that the rate at which spring onset progresses across the continent influences bird migration rates, such that individuals adjust migration timing within North America to phenological conditions they experience en route.To test our hypotheses, we used a continent‐wide automated radio telemetry network to track individual songbirds on spring migration between the U.S. Gulf Coast region and northern locations closer to their breeding grounds.We measured vegetation phenology using two metrics of spring onset, the spring index first leaf date and the normalized difference vegetation index (NDVI), then calculated the rate and timing of spring onset relative to bird detections.All individuals arrived in the southeastern United States well after local spring onset. Counter to our expectations, we found that songbirds exhibited a 'catching up' pattern: Individuals migrated faster than the green wave of spring onset, effectively closing in on the start of spring as they approached breeding areas.While surfing of resource waves is a well‐documented migration strategy for herbivorous waterfowl and ungulates, individual songbirds in our study migrated faster than the green wave and increasingly caught up to its leading edge en route.Consequently, songbirds experience a range of vegetation phenophases while migrating through North America, suggesting flexibility in their capacity to exploit variable resources in spring. [ABSTRACT FROM AUTHOR]