scholarly journals Predicting the Effects of Cerulean Warbler, Dendroica cerulea Management on Eastern Ontario Bird Species

2004 ◽  
Vol 118 (2) ◽  
pp. 229 ◽  
Author(s):  
Jason Jones ◽  
William J. McLeish ◽  
Raleigh J. Robertson

Single-species habitat management strategies are often undertaken without explicit consideration of their effects on the larger community. Here we explore the potential effects of managing eastern Ontario deciduous forests for the Cerulean Warbler (Dendroica cerulea) by examining its potential as a biodiversity indicator species and as an umbrella species. Our results indicate that the Cerulean Warbler would not be an effective biodiversity indicator, as its distribution across the studied landscape did not coincide with areas of high avian species richness. However, the Cerulean Warbler may be effective as an umbrella species for the maintenance of populations of other canopy-nesting species that require mature deciduous forest habitats. It is hoped that the conclusions reached in Ontario, while perhaps not directly transferable to all parts of the breeding range, encourage other Cerulean Warbler researchers to ask similar questions in their study areas.

The Auk ◽  
2001 ◽  
Vol 118 (3) ◽  
pp. 727-735 ◽  
Author(s):  
Jason Jones ◽  
Raleigh J. Robertson

Abstract We examined habitat selection by breeding Cerulean Warblers (Dendroica cerulea) at three spatial scales in eastern Ontario over three years (1997–1999). Territories were characterized by well-spaced large trees, with high canopies and dense foliage cover at heights between 12–18 m. Nesting habitat additionally was characterized by dense foliage cover above 18 m. The results of our nest-patch (0.04 ha circle around nest) and nest-site (0.01 ha circle) analyses indicate that male Cerulean Warblers may take active roles in nest-site selection when selecting territories. We conclude from our nest-patch and nest-site selection analyses that territories likely contain multiple nest patches and sites and that male Cerulean Warblers may defend areas with multiple nest patches or sites, which may attract females to settle with them. Whether or not Cerulean Warbler females use nest-site availability as a mate- or territory-choice cue remains unknown. We also tested the validity of a commonly made assumption that a random sampling of habitat by researchers is representative of the habitat actually available to birds and found that, in our study area, the assumption was invalid. Taken together, our results point toward the need to maintain sizeable stands of mature, deciduous forest to ensure the persistence of Cerulean Warblers in eastern Ontario. Population characteristics such as lower minimum area requirements and a resilience to habitat disturbance may make that an easier job in eastern Ontario than elsewhere in this species' breeding range.


2008 ◽  
Vol 18 (2) ◽  
pp. 164-180 ◽  
Author(s):  
Huw Lloyd

AbstractPoint count distance sampling surveys were conducted at three sites in the Cordillera Vilcanota to determine whether variation in high-Andean species richness, diversity and abundance was a reflection of Polylepis habitat quantity. Bird community and abundance measures revealed that there was considerably variation in bird species richness, diversity and mean encounter rates between large, medium, and small forest patches. Densities of Polylepis-dependent bird species (including five globally-threatened and eight restricted-range species) were greater in larger forest patches and differed significantly between different patch size categories. Density estimates for matrix-dependent species were higher in smaller Polylepis patches indicating that the matrix exerts an influence on bird species composition and abundance in remnant Polylepis forests, particularly smaller patches. Comparison of lowland forest habitat specialists using three categories of rarity revealed that between 19–22% of all Polylepis-dependent species were intrinsically rare within larger forest patches, and a greater number (34–74%) were rare in smaller forest patches. Population estimates for all species, in particular for all threatened species, were extremely low, numbering ⩽ 10 individuals at nine of the ten sites examined. The results suggest that declines in the densities of certain Polylepis birds may be predictable following habitat loss and that these patterns of rarity should govern population recovery goals through appropriate habitat restoration strategies. Such strategies are urgently required and must be designed to prevent further habitat loss, and to increase Polylepis habitat quantity to boost threatened bird populations in the Cordillera Vilcanota.Evaluaciones de distancias de puntos de conteo fueron conducidas en tres lugares en la Cordillera Vilcanota para determinar si la variación en la riqueza, diversidad y abundancia de las especies de los Andes altos, era un reflejo de la cantidad de hábitats de Polylepis. La comunidad de aves y su abundancia revelaron que hubo una considerable variación en la riqueza de especies, diversidad y la media encontrada en rangos parches de bosque comprendidos entre grandes, medios y pequeãos. La densidad de especies de aves dependientes de Polylepis (incluyendo cinco amenazados globalmente y ocho especies con rango restringido) fueron mayores en parches grandes de bosque y difirieron significativamente entre diferentes categorías de tamaãos de parche. La densidad estimada para especies matriz-dependientes fue mayor en pequeãos parches de Polylepis indicando que la matriz ejerce una influencia en la composición de especies de aves y abundancia en vestigios de bosques de Polylepis, particularmente parches pequeãos. En comparación con especialistas de hábitat de bosque bajo, empleando tres categorías de rareza revelaron que entre 19–22% de todos las especies dependientes de Polylepis fueron intrínsicamente raras dentro de parches grandes de bosque, y un número mayor (34–74%) fueron raras en los parches pequeãos de bosque. La población estimada para todas las especies, en particular para todas las especies amenazadas, fue extremadamente baja, contando ⩽ 10 individuos en nueve de los 10 sitios examinados. El resultado sugiere que la disminución en la densidad de ciertas aves de Polylepis se podría predecir después de la pérdida de hábitat y que esos patrones de rareza podrían servir como objetivos para la recuperación de la población a través de estrategias de restauración de hábitats apropiados. Este tipo de estrategias son requeridas con urgencia y deberían estar diseãadas para prevenir futuras pérdidas de hábitats, incrementar la cantidad de hábitat de Polylepis para aumentar la población de aves amenazadas en la Cordillera Vilcanota.


Check List ◽  
2010 ◽  
Vol 6 (2) ◽  
pp. 319
Author(s):  
Esteban Guevara ◽  
Tatiana Santander ◽  
Juan E. Guevara ◽  
Renán Gualotuña ◽  
Vinicio Ortiz

Sangay National Park is located at the mid-eastern Andean foothills of the Cordillera Oriental of Ecuador. We present a preliminary avifauna inventory corresponding to the lower zone of the Sangay National Park (SNP). One-hundred and twenty-seven bird species belonging to 39 families were recorded, including noteworthy records that represent range extensions for four species, Phaetornis hispidus (Gould 1846) (White-bearded Hermit), Ramphastos ambiguus Swainson 1823 (Black-mandibled Toucan), Phylloscartes orbitalis (Cabanis 1873) (Spectacled Bristle Tyrant), and Microcerculus bambla (Boddaert 1783) (Wing-banded Wren). We also obtained information on threatened species such as Aburria aburri (Lesson 1828) (Wattled Guan), Phlogophilus hemileucurus Gould 1860 (Ecuadorian Piedtail), and Dendroica cerulea (Wilson 1810) (Cerulean Warbler) and reproductive data on one species, Patagioenas speciosa (Gmelin 1789) (Scaled Pigeon). To our knowledge this is a first ornithological survey carried out at this specific site of the SNP.


2008 ◽  
Vol 86 (4) ◽  
pp. 329-337 ◽  
Author(s):  
John M. Tirpak ◽  
William M. Giuliano ◽  
C. Allan Miller

Declines in ruffed grouse ( Bonasa umbellus (L., 1766)) populations in the central and southern Appalachians may be linked to low brood survival. Therefore, managing for high-quality brood habitat could improve grouse numbers. Understanding how brood habitat selection affects survival and the spatial scale at which this occurs is therefore fundamental to developing effective habitat management strategies. From 1999–2002, we monitored 38 broods for 5 weeks post hatch and estimated utilization distributions (n = 28), site-scale habitat use (n = 21), and daily survival rate (mean = 0.966, range = 0.920–0.997, and n = 19). Relative to available habitat, broods selected sites with greater herbaceous ground cover and higher small (<2.5 cm diameter at breast height, DBH) stem densities and landscapes containing higher proportions of road and young deciduous forest. Herbaceous ground cover provided arthropod prey and concealment from predators and was a primary factor driving habitat selection. High stem densities and early successional habitats provided increased security, but were only used if adequate ground cover was present. Broods strongly selected roads and experienced higher survival near edges. However, higher road densities were associated with lower survival at the landscape scale. This pattern reflects the differential scale at which grouse and their predators respond to edge.


Fire Ecology ◽  
2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Marcelo H. Jorge ◽  
Sara E. Sweeten ◽  
Michael C. True ◽  
Samuel R. Freeze ◽  
Michael J. Cherry ◽  
...  

Abstract Background Understanding the effects of disturbance events, land cover, and weather on wildlife activity is fundamental to wildlife management. Currently, in North America, bats are of high conservation concern due to white-nose syndrome and wind-energy development impact, but the role of fire as a potential additional stressor has received less focus. Although limited, the vast majority of research on bats and fire in the southeastern United States has been conducted during the growing season, thereby creating data gaps for bats in the region relative to overwintering conditions, particularly for non-hibernating species. The longleaf pine (Pinus palustris Mill.) ecosystem is an archetypal fire-mediated ecosystem that has been the focus of landscape-level restoration in the Southeast. Although historically fires predominately occurred during the growing season in these systems, dormant-season fire is more widely utilized for easier application and control as a means of habitat management in the region. To assess the impacts of fire and environmental factors on bat activity on Camp Blanding Joint Training Center (CB) in northern Florida, USA, we deployed 34 acoustic detectors across CB and recorded data from 26 February to 3 April 2019, and from 10 December 2019 to 14 January 2020. Results We identified eight bat species native to the region as present at CB. Bat activity was related to the proximity of mesic habitats as well as the presence of pine or deciduous forest types, depending on species morphology (i.e., body size, wing-loading, and echolocation call frequency). Activity for all bat species was influenced positively by either time since fire or mean fire return interval. Conclusion Overall, our results suggested that fire use provides a diverse landscape pattern at CB that maintains mesic, deciduous habitat within the larger pine forest matrix, thereby supporting the diverse bat community at CB during the dormant season and early spring.


2016 ◽  
Vol 76 (4) ◽  
pp. 818-823 ◽  
Author(s):  
F. A. F. Jacomassa

Abstract The goal of this study was to identify which bird species consume Solanum granuloso-leprosum fruits and disperse its seeds. 60 hours of focal observations were carried out between April and May 2006 on the edge of a deciduous forest fragment in the Uruguay River region, Rio Grande do Sul state, Brazil. Ten species were observed in total removing 443 fruits. Saltator similis removed 61.8% of the fruits, followed by Tangara sayaca (17.1%), Pipraeidea bonariensis (11.7%), and T. preciosa (6.8%), while the remaining six species accounted for only 2.5% of the fruits removed. Most fruit removal occurred early in the day or mid-afternoon. The most common feeding behaviors were picking (60.7%), followed by stalling (23%) and hovering (16%). Birds flew more than 10 m from the fruit plant in 62% of the removal events. All bird species observed here may be considered potential dispersers of S. granuloso-leprosum, as they moved the seeds away from the mother plant where strong competition and predation are likely to occur. Results also suggest that S. granuloso-leprosum may be useful in ecological restoration programs.


2016 ◽  
Vol 71 ◽  
pp. 627-635 ◽  
Author(s):  
Francesco Valerio ◽  
Marco Basile ◽  
Rosario Balestrieri ◽  
Mario Posillico ◽  
Sergio Di Donato ◽  
...  

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