Journal of Raptor Research最新文献

{"title":"Commentary: Subadult Nest Occupancy Rates and Floater-To-Breeder Ratios in Raptor Population Assessment","authors":"W. G. Hunt, P. Law","doi":"10.3356/JRR-22-87","DOIUrl":"https://doi.org/10.3356/JRR-22-87","url":null,"abstract":"Subadult (immature) raptors of a variety of species are capable of holding breeding territories and even reproducing (Newton 1979, Steenhof et al. 1983). Robust populations, however, typically contain few, if any, pair members in pre-definitive plumage, and the general explanation is that adults tend to outcompete younger individuals for territory ownership where space is limiting. Their rarity as territory-holders can therefore be a useful indicator of breeding habitat saturation, whereas their increase has been considered ‘‘early warning’’ that vital rates (survival and reproduction) are insufficient to fill territorial space (Ferrer and Donazar 1996, Ferrer et al. 2003). Territory saturation also constitutes a threshold beyond which floaters (nonterritorial adults) can be expected to accumulate. The size of such a population and the ratio of floaters to territory-holders will stabilize if vital rates remain high enough to maintain saturation, a mode of population limitation known as Moffat’s equilibrium (Hunt 1998). The equilibrium floater-tobreeder ratio is useful in broadly indexing the durability of territory saturation as well as the degree of expected feedback of floater intrusions upon nest success (see Haller 1996). A stochastic population matrix model developed by Monzón and Friedenberg (2018) explored the floater dynamics of Moffat’s equilibrium (Hunt 1998, Hunt et al. 2017). Importantly, the rate of floater transition to the breeder stage was modeled dynamically so that transitions were determined by the availability of territories. Their model projected life-stage-structure and allowed computation of instantaneous floater-to-breeder ratios and rates of subadult nest occupancy in a hypothetical Golden Eagle (Aquila chrysaetos) population. The authors ran simulations of population decline and growth, habitat expansion and contraction, and valuably, the 10-yr cycling of a hypothetical prey population. Monzón and Friedenberg’s (2018) report emphasized that floater-to-breeder ratios and the incidence of subadult nest occupancy responded to these scenarios in ways indicating that neither, as a ‘‘snapshot metric,’’ can diagnose the status of a population in the absence of other information. For example, high instantaneous floater-to-breeder ratios characterized not only robust populations, but also those where territory occupancy was shrinking because of habitat loss. High rates of subadult occupancy manifested in both increasing and declining populations. In all, we found Monzón and Friedenberg’s (2018) modeling results consistent with Moffat’s equilibrium dynamics as described by Hunt (1998), Hunt and Law (2000), and Hunt et al. (2017). We believe that variations upon the authors’ algorithm can find useful application in studies of","PeriodicalId":16927,"journal":{"name":"Journal of Raptor Research","volume":"5 1","pages":"493 - 497"},"PeriodicalIF":1.7,"publicationDate":"2023-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78678491","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Book Review: Vultures of the World: Essential Ecology and Conservation","authors":"Matías A. Juhant, Evan McWreath, J. Burnett","doi":"10.3356/JRR-57-3-Book-Review","DOIUrl":"https://doi.org/10.3356/JRR-57-3-Book-Review","url":null,"abstract":"Vultures of the World: Essential Ecology and Conservation. By Keith L. Bildstein. 2022. Cornell University Press, Comstock Publishing Associates, Ithaca, New York, USA. ISBN: 978-1501761614. Hardcover, $25.29 and Kindle, $12.99. Dr. Keith Bildstein’s latest book, Vultures of the World: Essential Ecology and Conservation, provides an engaging look at vultures and condors, seeking to help us understand this widely recognized but underappreciated avian group. Bildstein is known to many Journal of Raptor Research (JRR) readers as a past Raptor Research Foundation Vice-President (1999–2002) and member of the Board of Directors (1988–1997). Bildstein is also a former Sarkis Acopian Director of Conservation Science at Hawk Mountain Sanctuary, Kempton, Pennsylvania, USA. His new book reflects the culmination of nearly two decades of personal experience observing and studying vultures worldwide, focusing on migration and movement behavior, physiology, and ecology of migratory and nonmigratory vulture species. We (MAJ, EM, and JB) appreciate the opportunity to review this book on vultures and condors, as the three of us study these full-time obligate scavengers in the western hemisphere. In his three-page preface, Bildstein makes two critical points that the new generation of vulture biologists should consider. The first point: Bildstein has broadened his perspectives over the decades by interacting with other research biologists, and without those interactions, this book could not have been written. Consequently, this point emphasizes the importance of humility and having or developing social abilities necessary to discuss the subjects of study with your peers. The second point: two monumental monographs by Brown and Amadon (1968) and Mundy et al. (1992) have provided an effective model to describe the essential ecology of these full-time obligate scavengers, facilitating Bildstein’s work on vultures at a global scale. The takehome message here is that regardless of the age of the reference, older literature can provide critical insight into the current knowledge of the subject of study. Vultures of the World provides thoughtful explanations to simple questions such as ‘‘Why are vultures the only full-time obligate scavengers in the vertebrate group? What physical and behavioral adaptations have evolved that allow them to inhabit a diverse set of habitats? How do vultures find and feast on rotting flesh?’’ Moreover, it provides helpful background on New World (family Cathartidae) and Old World (family Accipitridae) vultures. JRR readers may remember these terms refer only to the current species distributions and not their geographical origins, which is an important distinction, as Old World vultures may have evolved in the New World, and those we call New World vultures most likely evolved in the Old World. The scavenging habits of these two families are thought to have evolved independently, leading to adaptations such as large bodies, broad wings, power","PeriodicalId":16927,"journal":{"name":"Journal of Raptor Research","volume":"12 1","pages":"502 - 504"},"PeriodicalIF":1.7,"publicationDate":"2023-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87556222","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Toward Rapid Population Assessment for Raptor Conservation: Subadults, Floaters, Strawmen, and Context. A Response to Hunt and Law","authors":"J. Monzón, Nicholas A. Friedenberg","doi":"10.3356/JRR-22-117","DOIUrl":"https://doi.org/10.3356/JRR-22-117","url":null,"abstract":"Many raptors exhibit life history characteristics that simultaneously place them at conservation risk and make them difficult to study, including delayed reproduction, long life spans, low annual fecundity, and large seasonal movements. Developing effective methods for rapid assessment of raptor populations will improve the feasibility and timeliness of adaptive management. To this end, we used a stage-structured demographic model to evaluate the insight into population decline risk provided by two population structure measurements: subadult nest occupancy and the ratio of non-territorial ‘‘floater’’ adults to territorial breeders (Monzón and Friedenberg 2018). Here, we respond to a commentary by Hunt and Law (2023) that addresses our study’s premises. There is no disagreement that the metrics require further context to be diagnostic; however, Hunt and Law (2023) offer three specific criticisms of our study, calling them strawmen. Although we did not intend them as such, discussing each criticism here offers an opportunity to clarify how these demographic metrics are and should be interpreted. First, Hunt and Law (2023) assert that we proposed, as a strawman, that subadult nest occupancy has only one possible explanation. They are referring to our summary of previously published work suggesting ‘‘a high incidence of subadults on nests might characterize a population in decline or at high risk of decline because it may be depleted of adult breeders and floaters’’ (Monzón and Friedenberg 2018, citing Balbontı́n et al. 2003 and Ferrer et al. 2003). Our summary reflects the preponderance of studies on the subject. Even Hunt and Law (2023), shortly after pointing out the narrowness of our summary, establish the general rarity of subadult nesting among raptors and assert that it should be regarded as a meaningful warning sign even if observed at a low level. With this premise as a hypothesis, we explored various ecological scenarios that can yield high rates of subadult nest occupancy and then assessed the value of this snapshot metric for indicating risk of population decline. The metric on its own was useful for identifying scenarios of moderate decline risk but failed to discern cases of low and high risk (Monzón and Friedenberg 2018). The examples presented by Hunt and Law (2023) all provide additional ecological context with which to interpret the metric properly and share the theme of high adult mortality being an important factor—the exact conclusion we reached in our original study (Monzón and Friedenberg 2018). In the example of Golden Eagles (Aquila chrysaetos) in the Altamont Pass Wind Resource Area in California, a high rate of subadult nest occupancy is interpreted in the context of high adult mortality from collisions with wind turbines (Wiens and Kolar 2021). Similarly, the","PeriodicalId":16927,"journal":{"name":"Journal of Raptor Research","volume":"75 1","pages":"498 - 501"},"PeriodicalIF":1.7,"publicationDate":"2023-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88177034","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nest Usurpation by a Female Mississippi Kite (Ictinia mississippiensis)","authors":"C. Boal","doi":"10.3356/JRR-22-103","DOIUrl":"https://doi.org/10.3356/JRR-22-103","url":null,"abstract":"Virtually all species compete for resources, which can lead to aggressive intraand interspecific interactions between individuals (Scott and Fredericson 1951). These interactions may take the form of displays, aggressive chases, and physical contacts (Jamieson and Seymour 1983, Bildstein and Collopy 1985, Boal 2001). Among conspecifics, these interactions may be agonistic, which is an escalation of behaviors from threat displays (often ritualized) to aggression, ultimately resulting in the submission or death of one combatant (McGlone 1986). For example, territorial Harris’s Hawks (Parabuteo unicinctus) engage in posturing, display, and eventual attack if an intruding conspecific does not leave (Dawson and Mannan 1991). In more extreme cases, individuals may kill and cannibalize conspecifics (Allen et al. 2020). The Mississippi Kite (Ictinia mississippiensis) is a highly social, quasi-colonial species (Skipper 2018, Parker 2020). For example, in 2022 I monitored 52 nests among 20 urban parks (one to eight nests/ park) in Lubbock, Texas, USA, and documented a mean density of one nesting pair per 2.7 ha (62.46 SD). Additionally, large nonbreeding groups may communally roost in trees near occupied nests. Despite such close proximities, aggressive interactions between Mississippi Kites appear to be exceedingly rare, with only a few documented events that usually consist of adults chasing subadults away from nests (Shaw 1985, Parker 2020). In summer 2020, I banded a nesting female Mississippi Kite with a US Geological Survey Bird Banding Lab aluminum leg band and a plastic green-colored band with the white letters ME (hereafter G-ME). I did not band the male of the breeding pair. The pair’s 2020 nesting attempt was successful in fledging one young. On 4 June 2021, I confirmed the female G-ME had returned to the 2020 nest area. The 2020 nest had blown out, but the kites had constructed a new nest and I observed multiple copulations between an unbanded male and G-ME. On 23 June 2021 at approximately 1020 H CST, I approached the G-ME nest to assess breeding status. At this date, all the monitored kite nests in my study were in the incubation stage. Upon my arrival I observed G-ME standing on the north side of the nest and facing an unbanded adult female Mississippi Kite perched in the cup of the nest (Fig. 1). The two kites posed with gaped beaks, nape feathers erected, and wings flared out as they faced each other. An unbanded adult male was perched on a branch approximately 1 m above and to the side of the nest. Although I did not know when the interaction was initiated, I watched for more than 10 min as the two female kites commenced to fight on the nest. They began making pecking strikes at each other, progressing to breast to breast contact and batting at each other with their wings and making pecking strikes toward each other’s faces (Supplemental Material 1). When one bird struck out with its beak, the other would retract its head backward to avoi","PeriodicalId":16927,"journal":{"name":"Journal of Raptor Research","volume":"27 1","pages":"485 - 488"},"PeriodicalIF":1.7,"publicationDate":"2023-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87306140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Extirpation of Orange County, California, Breeding Burrowing Owl Population: The Convergence of Philopatry, Habitat Fragmentation, and Allee Effects","authors":"P. Bloom","doi":"10.3356/JRR-22-90","DOIUrl":"https://doi.org/10.3356/JRR-22-90","url":null,"abstract":"ABSTRACT. From 1898 through approximately 12 decades the status of the Burrowing Owl (Athene cunicularia) in coastal southern California and particularly Orange County was well documented. The earliest reports considered the species abundant along the south coastal slope, but starting about 1931, the breeding population slipped into a noticeable decline that continued until 2014, when the last known breeding attempt in Orange County occurred. Publications and reports from 1931–2016 have documented a chronic, but slow trend toward extirpation of the breeding population of coastal southern California from Santa Barbara County south through northern San Diego County. On the south coastal slope, only in southern San Diego County does a remnant breeding population exist. Causes of the Orange County decline include habitat loss, degradation, and fragmentation; California ground squirrel (Otospermophilus beecheyi) eradication; and coastal predator management at California Least Tern (Sterna antillarum browni) and Western Snowy Plover (Charadrius nivosus) nesting colonies. The impact of these factors was compounded by short natal and breeding dispersal distances and ultimately by Allee effects. This report documents the last known nesting attempts of Burrowing Owls in Orange County, California. Although it remains plausible that an occasional future nesting attempt may still occur, the species in Orange County, as well as nesting colonies in other coastal southern California counties, can now be regarded as ecologically extirpated. RESUMEN. Desde 1898 y durante las siguientes ocho décadas, el estatus de Athene cunicularia en la costa sur de California y particularmente en el Condado de Orange ha sido bien documentado. Los primeros informes consideraban que la especie era abundante a lo largo de la ladera costera sur, pero a partir de 1931, la población reproductiva comenzó a disminuir notablemente y esta tendencia continuó hasta 2014, cuando se produjo el último intento reproductivo conocido en el Condado de Orange. Diez publicaciones e informes diferentes (1931–2016) han documentado una tendencia crónica pero lenta hacia la extinción local de la población reproductiva de la costa sur de California desde el Condado de Santa Bárbara hasta el norte del Condado de San Diego. En la ladera costera sur, solo en el sur del Condado de San Diego existe una población reproductiva remanente. Las causas de la disminución en el Condado de Orange incluyen la pérdida, degradación y fragmentación del hábitat; la erradicación de la ardilla Otospermophilus beecheyi; y el manejo de depredadores costeros en colonias de anidación de Sterna antillarum browni y Charadrius nivosus. El impacto de estos factores se vio agravado por las cortas distancias de dispersión de nacimiento y reproducción y, en última instancia, por el efecto Allee. Este informe documenta los últimos intentos conocidos de anidación de A. cunicularia en el Condado de Orange, California. Aunque sigue siendo ","PeriodicalId":16927,"journal":{"name":"Journal of Raptor Research","volume":"9 1","pages":"475 - 484"},"PeriodicalIF":1.7,"publicationDate":"2023-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78730786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling the Spatial Distribution of Carcasses of Eagles Killed by Wind Turbines","authors":"M. Huso, D. Dalthorp, Jeffrey Mintz, T. Nygård, R. May","doi":"10.3356/JRR-21-53","DOIUrl":"https://doi.org/10.3356/JRR-21-53","url":null,"abstract":"ABSTRACT. Currently, the US Fish and Wildlife Service makes eagle permitting and management decisions nationwide based on a limited understanding of the impacts of wind power generation on eagles, and the factors that influence risk at a given facility. Accurate estimates of eagle mortality at wind power facilities form the basis for comparing the magnitudes of mortality rates in different areas and for measuring the benefits of proposed methods of minimizing the collision-caused impacts to eagle populations. Simple counts of observed eagle carcasses at wind facilities are almost certainly underestimates of the true mortality because fatalities can be removed by scavengers, be missed by searchers, or fall outside searched areas. For the latter, models of relative carcass density as a function of distance from the turbine can be fit to observed carcass locations and used to estimate the proportion of carcasses expected to land within an area of any configuration beneath a turbine. In the USA, however, it has been difficult to estimate these models for large birds such as Bald Eagles (Haliaeetus leucocephalus) and Golden Eagles (Aquila chrysaetos) due to inadequate numbers of dead eagles found at any single facility. In this case, analysis of a surrogate species might be useful to inform carcass distributions. We chose to model the carcass distribution of White-tailed Eagles (Haliaeetus albicilla) in Norway as an informative surrogate for Bald Eagles and Golden Eagles in the USA. Our three best-fitting parametric models were very consistent in estimating that 50% (95% CI: 40–60%) of White-tailed Eagle carcasses land within approximately 42 m of the turbines that had 70-m hubs and approximately 40-m blades. Although our models were fit to data from White-tailed Eagles and not Bald or Golden Eagles, applying these models when calculating mortality impacts of wind developments on both eagle species will likely improve the accuracy of post-construction mortality estimates, particularly at sites where substantial areas may be unsearchable. Accurate post-construction mortality estimates can inform pre-construction fatality prediction models. Resource managers can determine whether their conditions are sufficiently similar to those we modeled to warrant the use of these models for Bald and Golden Eagle carcass distributions. RESUMEN. Actualmente, el Servicio de Pesca y Vida Silvestre de EEUU toma las decisiones de permisos y gestión de las águilas en todo el país en función de una comprensión limitada tanto de los impactos que la generación de energía eólica produce sobre las águilas como de los factores que influyen en el riesgo de una instalación determinada. Las estimaciones precisas de la mortalidad de las águilas en las instalaciones de energía eólica aportan la información base necesaria para comparar las magnitudes de las tasas de mortalidad en diferentes áreas y para medir los beneficios de los métodos propuestos para minimizar los impactos causad","PeriodicalId":16927,"journal":{"name":"Journal of Raptor Research","volume":"234 1","pages":"456 - 467"},"PeriodicalIF":1.7,"publicationDate":"2023-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75911017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Vocal Activity Patterns of the Changeable Hawk-Eagle (Nisaetus cirrhatus) in Peninsular Malaysia during Mid-Breeding Season","authors":"Amera Natasha Mah Muhammad Adam Mah, C. L. Puan, M. Zakaria","doi":"10.3356/JRR-22-72","DOIUrl":"https://doi.org/10.3356/JRR-22-72","url":null,"abstract":"ABSTRACT. Vocalization in birds serves an important role in territory establishment and mate attraction as well as maintaining conspecific interactions and providing signals pertaining to food or threat. In Malaysia, most raptor behavioral studies on vocalization have been carried out on nocturnal raptors. Such studies have often been limited by the difficulty of accessing habitats where forest species reside and by raptors' elusive behaviors. We assessed the vocalization and vocal activity patterns of a common diurnal raptor, the Changeable Hawk-Eagle (Nisaetus cirrhatus), in an isolated lowland forest reserve, the Ayer Hitam Forest Reserve in Selangor, Malaysia, in mid-April 2021. Automated bioacoustics recorders were placed for 5 d in four different sites to passively collect the hawk-eagles' vocalizations. We recorded 480 hr of calls over the 5 d and the Changeable Hawk-Eagle uttered at least seven call types, with peak and longer call events at midday (1100 H and 1200 H, respectively). Calls were heard from 30 min before sunrise (0600 H) until shortly after sunset (1900 H). Call type 1 was by far the most common call type (2738 calls over 5 d) and was uttered throughout the day, possibly during flight and when perched. Other call types were uttered from late morning (1000 H) with exception of call type 3, which was uttered earlier (0900 H). Our findings may help provide improved raptor survey methods as well as fill the knowledge gap for diurnal raptor vocalizations in Malaysia. RESUMEN. La vocalización en las aves cumple un papel importante en el establecimiento del territorio, en la atracción de la pareja, en el mantenimiento de interacciones conespecíficas y en la emisión de señales relacionadas con comida o amenaza. En Malasia, la mayoría de los estudios de comportamiento de rapaces sobre vocalización se han llevado a cabo en rapaces nocturnas. Dichos estudios a menudo se han visto limitados por la dificultad de acceder a los hábitats donde residen las especies de bosque y por los comportamientos esquivos de las aves rapaces. Evaluamos la vocalización y los patrones de actividad vocal de una rapaz diurna común, Nisaetus cirrhatus, en una reserva forestal aislada de tierras bajas, la Reserva Forestal Ayer Hitam en Selangor, Malasia, a mediados de abril de 2021. Se colocaron grabadores bioacústicos automatizados durante cinco días en cuatro sitios diferentes para recolectar pasivamente las vocalizaciones de N. cirrhatus. Registramos 480 horas de llamadas durante los cinco días y N. cirrhatus emitió al menos siete tipos de llamadas, con un pico de llamadas y llamadas más largas al mediodía (1100 H y 1200 H, respectivamente). Las llamadas se escucharon desde 30 minutos antes del amanecer (0600 H) hasta poco después del atardecer (1900 H). El tipo 1 de llamada fue por mucho el más común (2738 llamadas durante cinco días) y se emitió durante todo el día, posiblemente durante el vuelo y cuando estaba posado. Otros tipos de llamadas se emitieron","PeriodicalId":16927,"journal":{"name":"Journal of Raptor Research","volume":"35 1","pages":"393 - 404"},"PeriodicalIF":1.7,"publicationDate":"2023-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75517741","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Conservation of Asian Raptors in the Changing Environment: Continued Need for Local, Regional, and Global Collaborative Strategies","authors":"C. L. Puan","doi":"10.3356/JRR-57-3-Introduction","DOIUrl":"https://doi.org/10.3356/JRR-57-3-Introduction","url":null,"abstract":"Asia, as the largest continent, comprises a wide range of biomes that host more than 230 species of diurnal and nocturnal raptors, with especially high biodiversity toward the equator. In addition, Asia holds numerous endemic and rare species specialized for particular habitats; unfortunately, many of these are threatened and/or understudied. About one quarter of Asia’s raptors are migratory, and migrating raptors provide a significant attraction for tourists and birdwatchers, which contributes to local income generation, and education and research at migratory hotspots and overwintering sites. Such vast migratory movements have been documented at prominent count sites such as Chumphon in Thailand, Tanjung Tuan in Malaysia, and Kenting in Taiwan, thanks to the efforts of many volunteers. Asian raptors serve key ecosystem functions and services, owing to their diverse trophic levels and ecological niches. For example, the Barn Owl (Tyto alba) serves as a biological control agent in many agricultural areas in Southeast Asia. Scavenging vultures in South, Central, and East Asia remove carcasses while simultaneously preventing the spread of diseases. This implies that the absence or changes in raptor populations could potentially lead to adverse cascading effects such as competitive exclusion, intraguild predation, and extirpation or extinction. In Southeast Asia, many raptor habitats are threatened by anthropogenic activities linked to drastic land development and exploitation of natural resources to support the growth of human populations. In addition to habitat loss and degradation, raptors of Asia also face multiple threats ranging from collisions with wind power generation facilities or vehicles, to electrocutions, to secondary poisoning through agrochemicals. Despite the presence of some laws and regulations, poaching and illegal trade for consumption and pet businesses that involve raptors remain problematic in Asia. Some more recent threats also should not be overlooked. Falconry activity in Southeast Asia seems to be a new trend that has been promoted via social media, although tracing the sources of supply and demand of such activities is difficult. Some of the more localized issues posing threats to raptors include feeding of unnatural food to coastal raptors as part of tourism attractions, intentional and accidental trapping of birds by farmers and fishermen, and limestone quarrying. Thanks to the efforts of many local raptor researchers and volunteers, there have been increasing numbers of ecological studies on Asian raptors over the last two decades, which is encouraging for raptor conservation. However, there is still a dearth of studies on many forest-dependent species, island endemics, and habitat specialists with small geographic ranges and/or long generation times. Many of these species are extinction-prone, found in habitats that are difficult to access, elusive, and scarcely distributed. Given the long-term effects of global clim","PeriodicalId":16927,"journal":{"name":"Journal of Raptor Research","volume":"49 1","pages":"341 - 343"},"PeriodicalIF":1.7,"publicationDate":"2023-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84326934","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Full Annual Cycle of the American Kestrel: State of the Knowledge, Information Gaps, and Conservation Needs","authors":"James C. Bednarz, Jean-François Therrien","doi":"10.3356/jrr-introduction","DOIUrl":"https://doi.org/10.3356/jrr-introduction","url":null,"abstract":"","PeriodicalId":16927,"journal":{"name":"Journal of Raptor Research","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135640848","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Patterns of Water Use by Raptors in the Southern Great Plains","authors":"C. Boal, B. Bibles, Trevor S. Gicklhorn","doi":"10.3356/JRR-21-70","DOIUrl":"https://doi.org/10.3356/JRR-21-70","url":null,"abstract":"ABSTRACT. There is a paucity of data evaluating water use by raptors. Although raptors are believed to satisfy their water requirements through metabolic processes, they are known to experience reduced reproductive success during periods of drought, and there is evidence of water being important for site occupancy in arid landscapes. Several raptor species have a seasonal or year-round presence in west Texas, a drought-prone, semi-arid region of the Southern Great Plains. We examined species-specific timing of free water use by common raptors in this region, and examined environmental conditions associated with water use. We collected 4549 camera trap-days of data across 4 yr at ten human-made water sources placed for cattle. We recorded 14 species of raptors among the 1177 detections of raptors visiting water sources; of these, 1084 raptors (92.1%) perched at tanks, and 93 (7.1%) flew by tanks. Of the raptors that perched at tanks, 63.5% drank and 20.8% both bathed and drank. Barn Owls (Tyto alba; 35.6%), Swainson's Hawks (Buteo swainsoni; 32.0%), and Northern Harriers (Circus hudsonius; 21.0%) were the predominate species detected. Visits by Northern Harriers and Swainson's Hawks increased with increasing temperature and decreasing precipitation. Visits by Barn Owls increased with increasing drought severity. Further, detections per 100 trap-days increased substantively across our 4-yr study period during which the region experienced one of the worst droughts on record. Although our data do not demonstrate these raptors require free water, they do reveal an increasing use of free water in relation to hotter and drier conditions. How this influences survival and reproduction remains unknown, but may become a pressing question because current climate models predict the study area will experience increases in heat and decreases in precipitation. RESUMEN. Hay escasez de datos que evalúen el uso del agua por parte de las aves rapaces. Aunque se cree que las aves rapaces satisfacen sus necesidades de agua a través de procesos metabólicos, se sabe que experimentan un éxito reproductivo reducido durante los períodos de sequía, y hay evidencia de que el agua es importante para la ocupación de sitios en paisajes áridos. Varias especies de aves rapaces tienen una presencia estacional o anual en el oeste de Texas, una región semiárida en el sur de las Grandes Llanuras propensa a la sequía. Examinamos el momento específico de uso de agua libre de cada especie para las aves rapaces comunes en esta región, y analizamos las condiciones ambientales asociadas con el uso del agua. Recolectamos 4549 días de datos de cámaras trampa a lo largo de cuatro años en diez fuentes de agua artificiales colocadas para el ganado. Registramos 14 especies de rapaces entre las 1177 detecciones de rapaces visitando las fuentes de agua; de estas, 1084 rapaces (92.1%) se posaron en los tanques y 93 (7.1%) volaron cerca de los tanques. De las rapaces que se posaron en los tanques, e","PeriodicalId":16927,"journal":{"name":"Journal of Raptor Research","volume":"55 1","pages":"444 - 455"},"PeriodicalIF":1.7,"publicationDate":"2023-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88817088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}