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Assessing the Uncertainty of Total Seabird Bycatch Estimates Synthesized from Multiple Sources with a Scenario Analysis from the Western and Central Pacific 多来源综合海鸟副渔获量估算的不确定性评估及中西太平洋情景分析

Western Birds Pub Date : 2022-08-10 DOI: 10.3390/birds3030017

Can Zhou, B. Liao

{"title":"Assessing the Uncertainty of Total Seabird Bycatch Estimates Synthesized from Multiple Sources with a Scenario Analysis from the Western and Central Pacific","authors":"Can Zhou, B. Liao","doi":"10.3390/birds3030017","DOIUrl":"https://doi.org/10.3390/birds3030017","url":null,"abstract":"Each year, billions of seabirds undertake migrations, connecting remote regions of the world, potentially synchronizing population fluctuations among distant areas. This connectedness has implications for the uncertainty calculations of the total seabird bycatch estimate at a regional/global scale. Globally, fisheries bycatch poses a major problem in fishery management, and estimating the uncertainty associated with a regional/global seabird bycatch estimate is important because it characterizes the accuracy and reliability of the fisheries’ impact on the seabird populations. In this study, we evaluate different assumptions underlying the estimation of the variability of the total seabird bycatch at a regional/global scale based on local assessment reports. In addition to theoretical analysis, we also simulate multiple spatially distant separately managed areas with relatively low levels of observer coverage, based on bycatch data from the Western and Central Pacific Fisheries Commission convention area. The results show that assuming a completely synchronized variation produced the most conservative uncertainty estimate and it also missed an opportunity to improve the precision. Simplified correlation structures also failed to capture the complex dynamics of bycatch rates among spatially distant areas. It is recommended to empirically estimate the correlation of bycatch rates between each pair of sources based on bycatch rate time series.","PeriodicalId":52426,"journal":{"name":"Western Birds","volume":"29 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78857295","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Breeding Status and First Nest Record of the Lesser Goldfinch in Montana 蒙大拿州小金翅雀的繁殖状况及首次筑巢记录

Western Birds Pub Date : 2022-08-01 DOI: 10.21199/wb53.3.5

P. Hendricks, A. Mitchell

引用次数: 0

Apparent Predation by Rock Wren of Common Sagebrush Lizard 岩鹪鹩对山艾树蜥蜴的明显捕食

Western Birds Pub Date : 2022-08-01 DOI: 10.21199/wb53.3.8

D. Casey, P. Hendricks

{"title":"Apparent Predation by Rock Wren of Common Sagebrush Lizard","authors":"D. Casey, P. Hendricks","doi":"10.21199/wb53.3.8","DOIUrl":"https://doi.org/10.21199/wb53.3.8","url":null,"abstract":"analyses of the stomach contents of wrens (Troglodytidae) rarely report verte- brates (Beal et al. 1916, Bent 1948, Poulin et al. 2001, lopes et al. 2005), and few published records exist of wrens capturing and consuming vertebrate prey. We report here on a rock Wren ( Salpinctes obsoletus ) that was seen apparently preying upon a Common Sagebrush lizard ( Sceloporus graciosus ). The observation occurred on 11 June 2015 during the Western Field Ornithologists convention held in Billings, Montana, on a field trip Casey led to Bear Canyon. Bear Canyon is located in Carbon County on the south side of the Pryor Mountains in south-central Montana at the northern edge of the Wyoming Basin Ecoregion near the Montana/Wyoming border (Marks et al. 2016). This arid canyon is bounded by outcropped limestone and sup-ports a dominant vegetation of utah Juniper ( Juniperus osteosperma ), limber Pine ( Pinus flexilis ), and Big Sagebrush ( Artemisia tridentata ). at about 10:00 MDT, while surveying a brushy and rubble-filled draw (45.0777° N, 108.5393° W; 1580 m elevation), we found a rock Wren already grasping in its bill a small lizard by the neck (Figure 1). We watched and photographed the bird from a distance of approximately 10 m for at least 60 seconds. During that time the wren acted alert to our presence but nevertheless stayed in one location in full view of the group. The wren twice struck the lizard on a rock, as if to kill it, although we saw no movement by the lizard during our observation. after this brief period the wren moved out of our view and was not seen again. From the wren’s behavior and the fresh body condition of the lizard, we assume that it captured the lizard alive","PeriodicalId":52426,"journal":{"name":"Western Birds","volume":"148 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73149017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Willow Flycatcher Nesting within Narrowleaf Cottonwood in the Sierra Nevada 内华达山脉窄叶棉杨内筑巢的柳捕蝇鸟

Western Birds Pub Date : 2022-08-01 DOI: 10.21199/wb53.3.7

S. E. Dietrich

{"title":"Willow Flycatcher Nesting within Narrowleaf Cottonwood in the Sierra Nevada","authors":"S. E. Dietrich","doi":"10.21199/wb53.3.7","DOIUrl":"https://doi.org/10.21199/wb53.3.7","url":null,"abstract":"in the Sierra Nevada the Willow Flycatcher (Empidonax traillii brewsteri) typically nests within wetlands in high-elevation meadows (Green et al. 2003), almost always in shrubby willows (Salix spp.) and alders (Alnus spp.) (Serena 1982, harris et al. 1987, Valentine 1987, Sanders and Flett 1989, Bombay et al. 2003) and rarely more than 3 m off the ground (Beedy and Pandolfino 2013). Occasionally, however, it nests in more complex multilayered riparian woodland comprising a shrub understory and an upper canopy featuring larger trees such as cottonwood and aspen (Populus spp.; Dietrich 2020), as elsewhere in the species’ range (Sogge et al. 2010). During surveys for nesting Willow Flycatchers in June 2021, i located a nest in a narrowleaf cottonwood (Populus angustifolia) tree along the Little Truckee river near Stampede reservoir in the Tahoe National Forest. The nest was 4.5 meters high, and the nest tree was surrounded by a mix of aspen and other cottonwood trees but also included an understory of shrubby willows (Figure 1). The cottonwood with the nest was approximately 8.5 meters tall, and other nearby cottonwood trees were similar in height. Nearby aspen trees were much taller (>10 m), and the willow shrubs of the understory were shorter (<3 m). The cup nest was located near the main trunk where two branches came together and appeared to be composed of grass and sedge-like vegetation (Figure 1). The area around the nest was dense with cottonwood branches and leaves that kept the nest well concealed and shaded. This group of riparian trees and shrubs were growing on a large sediment bar forming an island with channels on both sides near where the river flows into Stampede reservoir. Sogge et al. (2010) reported Southwestern Willow Flycatchers (E. t. extimus) nesting in smaller willow shrubs at high elevations in the Southwest but also in larger box elder (Acer negundo), coast live oak (Quercus agrifolia), russian olive (Elaeagnus angustifolia), and salt cedar (Tamarix spp.) trees. Whitfield et al. (1999) reported Southwestern Willow Flycatchers nesting in large willows and occasionally","PeriodicalId":52426,"journal":{"name":"Western Birds","volume":"20 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81365593","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Molt Strategies by Age and Subspecies in the Willow Flycatcher 依年龄及亚种之柳条捕蝇者换羽策略

Western Birds Pub Date : 2022-08-01 DOI: 10.21199/wb53.3.4

P. Pyle, Blaine H. Carnes

{"title":"Molt Strategies by Age and Subspecies in the Willow Flycatcher","authors":"P. Pyle, Blaine H. Carnes","doi":"10.21199/wb53.3.4","DOIUrl":"https://doi.org/10.21199/wb53.3.4","url":null,"abstract":"We clarify the molt strategies of the Willow Flycatcher (Empidonax traillii) by subspecies through the examination of 455 museum specimens. Most and typically all juvenile primary coverts are retained during the preformative molt in fall and winter, allowing yearlings to be distinguished from older birds from their first spring through their second fall. In addition to replacing the body feathers and some to (usually) all secondary coverts and tertials, the preformative molt can include no other remiges or rectrices (46% of specimens), all remiges and rectrices (33%), or some remiges in an “eccentric” sequence (21%). During the prealternate molt, replacement of upper wing coverts and tertials is much less extensive than in the preformative molt, varying from replacement of no feathers in 27% of specimens to replacing more than half of the median and greater coverts and all three tertials in other specimens. Both the preformative and the first prealternate molts are significantly more extensive in eastern E. t. traillii than in the three western subspecies (brewsteri, adastus, and extimus). The definitive prealternate molt is also significantly more extensive than the first prealternate molt in the western subspecies but not in traillii. These differences between traillii and the other subspecies may result from longer migration distances, hence more solar exposure on an annual basis, and different molt-strategy dynamics between eastern and western North American passerines, perhaps relating to preferences for moister habitats. Further investigation is needed on the timing of molts on the winter grounds and the extent of body-feather replacement during the prealternate molt.","PeriodicalId":52426,"journal":{"name":"Western Birds","volume":"27 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84201223","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

First Record of the White-faced Ibis Nesting in Baja California Sur 下加利福尼亚南部白面朱鹮筑巢的首次记录

Western Birds Pub Date : 2022-08-01 DOI: 10.21199/wb53.3.6

G. Marrón, Luisa Marrón, R. Carmona

引用次数: 0

Habitat-Patch Occupancy of Western Screech-Owls in Suburban Southern California 南加州郊区西部尖声猫头鹰栖息地斑块占用情况

Western Birds Pub Date : 2022-08-01 DOI: 10.21199/wb53.3.2

Jonah Gula

引用次数: 0

The Tricolored Blackbird in Washington State: First Assessment of Status and Distribution 华盛顿州的三色黑鸟:地位和分布的首次评估

Western Birds Pub Date : 2022-08-01 DOI: 10.21199/wb53.3.1

A. J. McCormick