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Larval surveys can be an important tool in butterfly studies serving many purposes including determining species presence. Current survey recommendations for the imperiled frosted elfin Callophrys irus (Godart, 1824) (Family: Lycaenidae) include use of larval surveys for detecting species presence. But similar-appearing larvae of the gray hairstreak Strymon melinus (Hubner, 1818) (Family: Lycaenidae) also occur on C. irus host plants, which if misidentified as C. irus can result in false-positive detections. We reared C. irus and S. melinus larvae (n = 61 and n = 16 respectively) and assessed three characteristics of late instar larvae for distinguishing between them in the field. Larval body coloration overlapped for both species (pale green and pale pink) though C. irus was typically green while S. melinus was typically pale pink or red. Cranial pigmentation was also a helpful though imperfect distinguishing characteristic accurately identifying 65 (94.20%) of 69 larvae. The ratio of cranial width to distance between the sensory setae insertions on the prothoracic shield was a definitive distinguishing characteristic with C. irus having ratios <2.20 and S. melinus having ratios >2.20. We recommend observers determine the presence of C. irus at a given site based on multiple larvae (2-3 individuals minimum) if using a combination of body color and cranial pigmentation, or on one individual larva if using ratio measurements. Both larval body color and cranial pigmentation can be determined in the field; the former with the naked eye and the latter with a 60x hand lens. Ratio measurements require use of a dissecting microscope ex-situ. [ABSTRACT FROM AUTHOR]

King's hairstreak, Satyrium kingi (Klots and Clench, 1952), is rarely encountered throughout its range, with relatively little known about its life history and behavior. While adults can be difficult to study in the field, observations of caterpillars may inform management as their presence and position on host trees, Symplocos tinctoria, elucidates both habitat and host tree preferences. We surveyed for King's hairstreak caterpillars and adults in three management units in a Maryland floodplain forest. The units were managed with either prescribed fire and/or harvesting timber and also differed in time-since-management. Caterpillars were surveyed at night using UV flashlights from the ground and in the canopy using an articulated lift. We examined caterpillar frequency on different size classes of S. tinctoria within the three management units, and examined the ratio of caterpillar heights relative to the height of occupied S. tinctoria trees. We did not find any statistical differences in caterpillar frequency across different tree heights. The mean ratio of caterpillar heights from the ground relative to the height of the tree appeared normally distributed. We could not differentiate between management units in the model due to the lack of replication for time-since-management, however our observations and results may have practical implications for land managers. [ABSTRACT FROM AUTHOR]

Grassland birds have the highest rates of population declines and are among the highest priority birds for conservation in North America. Although significant effort has been conducted on the breeding ecology of many grassland birds, there have been limited investigations into wintering ecology. We used systematic mist-netting to conduct a five-year assessment of wintering return rates, patch fidelity, and response to prescribed fire for Grasshopper and Savannah Sparrows on grasslands in the Corkscrew Regional Ecosystem Watershed of southwest Florida. Mean annual apparent return rate was 23.9% for Grasshopper Sparrow and 16.1% for Savannah Sparrow, but the addition of gap-year birds (not captured in one year but captured in the following year) increased those rates to 27.7% for Grasshopper Sparrow and 17.4% for Savannah Sparrow. Patch fidelity (returning to the same net lane from the previous capture) was 73.4% between-season for Grasshopper Sparrow and 17.1% for Savannah Sparrow. Within-season patch fidelity was 69.3% for Grasshopper Sparrow and 38.7% for Savannah Sparrow. The differences between species were significant for both between-season and within-season fidelity rates. Grasshopper Sparrow capture rates were significantly higher in years one and two post- fire, but not in year three post-fire when they were similar to the pre-fire levels. The pattern of post-fire capture rates for Savannah Sparrow was similar, but the return to pre-fire levels occurred in year two post-fire. The top performing model for both Grasshopper and Savannah Sparrows was the model that included both the management unit and whether the unit was burned. The number of unique captures post-fire was significantly more for Grasshopper Sparrow (48.4%) and Savannah Sparrow (91.1%) than pre-fire. Given the continental concern for Grasshopper Sparrow and the continual loss of grassland habitat nationally and regionally, the CREW Grasslands represents important winter habitat and may be representative of the significance of south Florida to wintering grassland birds. [ABSTRACT FROM AUTHOR]

The frosted elfin (Callophrys irus) butterfly inhabits landscapes that may be subject to frequent fire to be sustained. Frosted elfins pupate primarily in leaf litter, at the soil surface, or just below it, and may suffer high mortality rates when fires occur. Gathering better information on this source of mortality is critical to planning prescribed fire operations in a manner conducive to the long‐term survival of the species.We buried lab‐reared frosted elfin pupae (n = 61) at 0.75 cm (n = 31) or 1.75 cm (n = 30) below the ground and conducted two experimental fires that mimicked typical prescribed fires.Eighteen of 30 (60%) buried at 1.75 cm survived 4 weeks postburn; no pupae buried at 0.75 cm survived. Most (n = 17) of the pupae that survived successfully enclosed the following year. Surviving pupae encountered lower maximum temperatures and were exposed to shorter durations of above‐lethal temperatures compared to those that died.Our data demonstrate that high mortality rates can be expected due to fire, yet fire remains a critical tool for maintaining the habitat. Fire practitioners should mitigate losses by using ignition patterns and suboptimal burn conditions to reduce fire intensity, or burn in a mosaic pattern across the landscape to ensure enough survival to perpetuate frosted elfin populations. [ABSTRACT FROM AUTHOR]

The article titled "Vocalizations Help Distinguish Male and Female Brown-Headed Nuthatches (Sitta pusilla) in the Field" discusses the discovery of sex-based vocalizations in the Brown-Headed Nuthatch, a cooperatively breeding species found in mature pine forests of the southeastern United States. The researchers have observed distinct vocalizations that can be used to differentiate between males and females in the field. Female nuthatches produce higher-pitched serial vocalizations with frequent peeps and multiple-syllable twitters, while male vocalizations lack these characteristics. This finding provides valuable insights into the behavior and ecology of this species and highlights the benefits of long-term field studies. [Extracted from the article]

Although species reintroduction attempts are now common, monitoring of reintroduction attempts rarely extends beyond initial population establishment. This short timespan likely fails to document long‐term population stability, subtle changes in behavior, and the potentially larger effects that some reintroduced species may have on other species. The Red‐cockaded Woodpecker (RCW; Dryobates borealis) is an important habitat specialist and ecosystem engineer that excavates cavities in living trees. Excavation of natural RCW cavities can take years to complete, but they also persist for many years and are used by many other species. We quantified characteristics of cavity trees excavated by RCWs (n = 44) in two populations that were reintroduced to unoccupied areas more than 10 years earlier. We measured features associated with heartwood rot and used generalized linear mixed effects regression to determine whether these features differed for trees selected for cavity excavation compared with random neighboring trees. We also assessed population trends for cavity‐nesting species that commonly used RCW cavities on one of the sites. Height of first live limb was the only factor distinguishing natural RCW cavity trees from control trees. Four of six cavity‐nesting species monitored increased significantly following RCW establishment. The increases may relate to the many natural and artificial cavities created during the reintroduction effort. Future reintroductions of the RCW should lead to successful natural cavity excavation if sufficiently large trees with smaller live crowns are present. Future efforts may also benefit the broader community of cavity‐nesting birds. [ABSTRACT FROM AUTHOR]