WITHIN-TERRITORY HABITAT USE AND MICROHABITAT SELECTION BY MALE CERULEAN WARBLERS (DENDROICA CERULEA)

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.

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Habitat use and microhabitat selection of two lizard species with different niche requirements in a resource availability gradient

Studies on Neotropical Fauna and Environment ◽

10.1080/01650521.2020.1752549 ◽

2020 ◽

pp. 1-13

Author(s):

Sergio Alejandro Terán-Juárez ◽

Eduardo Pineda ◽

Jorge Víctor Horta-Vega ◽

José Rogelio Cedeño-Vázquez ◽

Alfonso Correa-Sandoval ◽

...

Keyword(s):

Habitat Use ◽

Resource Availability ◽

Microhabitat Selection ◽

Lizard Species ◽

Selection Of

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MINIMUM ESTIMATES OF SURVIVAL AND POPULATION GROWTH FOR CERULEAN WARBLERS (DENDROICA CERULEA) BREEDING IN ONTARIO, CANADA

The Auk ◽

10.1642/0004-8038(2004)121[0015:meosap]2.0.co;2 ◽

2004 ◽

Vol 121 (1) ◽

pp. 15 ◽

Cited By ~ 34

Author(s):

Jason Jones ◽

Jennifer J. Barg ◽

T. Scott Sillett ◽

M. Lisa Veit ◽

Raleigh J. Robertson

Keyword(s):

Population Growth ◽

Dendroica Cerulea ◽

Cerulean Warblers

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Cerulean Warbler (Dendroica Cerulea) Microhabitat and Landscape-Level Habitat Characteristics in Southern West Virginia

The Auk ◽

10.1093/auk/122.2.497 ◽

2005 ◽

Vol 122 (2) ◽

pp. 497-508 ◽

Cited By ~ 6

Author(s):

Cathy A. Weakland ◽

Petra Bohall Wood

Keyword(s):

West Virginia ◽

Forest Fragmentation ◽

Microhabitat Use ◽

Dendroica Cerulea ◽

Cerulean Warbler ◽

Open Canopy ◽

Territory Density ◽

Cerulean Warblers ◽

Mountaintop Mining ◽

Spot Mapping

AbstractThe Cerulean Warbler (Dendroica cerulea) is a species of conservation concern in eastern North America, where declines in its population have been documented over the past several decades. A high proportion of the population occurs in forested areas of southern West Virginia, where it may be threatened by loss and degradation of forested habitat from mountaintop mining and valley fill (MTMVF). We examined, from a landscape perspective, the effects of forest fragmentation (in particular, effects of fragment size and response to edges) on Cerulean Warblers, using territory mapping techniques and geographic information system (GIS) technology in portions of four counties in southwestern West Virginia. We quantified landscape characteristics from digitized aerial photographs and measured microhabitat characteristics on spot-mapping plots. Territory density of Cerulean Warblers was 4.6 territories per 10 ha in intact forest and 0.7 territories per 10 ha in fragmented forest. The best habitat model included both landscape and microhabitat variables and indicated that territory density increased with increasing snag density, percentage of canopy cover >6–12 m and >24 m in height, and distance from mine edge. Models for predicting microhabitat use at the territory level were weak, indicating that microhabitat characteristics of territories were similar to habitat available on spot-mapping plots. The species did not appear to avoid internal edges, such as natural canopy gaps and open-canopy or partially open-canopy roads. Territory placement on ridges was greater than expected, and in bottomlands (ravines) and midslopes less than expected, given availability. Fifty percent of all territories were on ridges. Preference for ridges suggests that MTMVF may have a greater effect on Cerulean Warbler populations than other sources of forest fragmentation, given that ridges are removed in MTMVF. Our data indicate that Cerulean Warblers are negatively affected by mountaintop mining from loss of forested habitat, particularly ridgetops, and from degradation of remaining forests, as evidenced by lower territory density in fragmented forests and lower territory density closer to mine edges.

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Sociality and Foraging Behavior of the Cerulean Warbler in Venezuelan Shade-Coffee Plantations

The Condor ◽

10.1093/condor/102.4.958 ◽

2000 ◽

Vol 102 (4) ◽

pp. 958-962 ◽

Cited By ~ 5

Author(s):

Jason Jones ◽

Paolo Ramoni Perazzi ◽

Erin H. Carruthers ◽

Raleigh J. Robertson

Keyword(s):

Foraging Behavior ◽

Territory Size ◽

Flock Size ◽

Adult Males ◽

Shade Coffee ◽

Coffee Plantations ◽

Dendroica Cerulea ◽

Cerulean Warbler ◽

Mixed Species Flocks ◽

Cerulean Warblers

Abstract We examined the use of Venezuelan shade-coffee plantations by the Cerulean Warbler (Dendroica cerulea) and other Neotropical migrants. Cerulean Warblers were commonly observed as pairs in mixed-species flocks. Average (± SE) flock size was 13 ± 2 species with 22 ± 3 individuals. Average flock territory size was 2.5 ± 0.2 ha. No differences were detected in foraging behavior (maneuvers, location, or success) among adult males, adult females, and immature birds. Adult males were often observed visiting flowers of canopy trees. The results of this study indicate that shade coffee plantations may provide suitable wintering habitat for Cerulean Warblers although comparisons with other habitats are needed.

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Minimum Estimates of Survival and Population Growth for Cerulean Warblers (Dendroica Cerulea) Breeding in Ontario, Canada

The Auk ◽

10.1093/auk/121.1.15 ◽

2004 ◽

Vol 121 (1) ◽

pp. 15-22

Author(s):

Jason Jones ◽

Jennifer J. Barg ◽

T. Scott Sillett ◽

M. Lisa Veit ◽

Raleigh J. Robertson

Keyword(s):

Growth Rate ◽

Population Growth ◽

Adult Male ◽

Population Growth Rate ◽

Adult Mortality ◽

Leslie Matrix ◽

Population Declines ◽

Male Mortality ◽

Dendroica Cerulea ◽

Cerulean Warblers

Abstract The Cerulean Warbler (Dendroica cerulea) tops many lists of species of conservation concern because of severe population declines and habitat loss. Here we present the first robust estimates of annual survival and population growth rates for this species. We used capture—mark—recapture models to estimate survival of adult male Cerulean Warblers in an eastern Ontario population that has been studied since 1994. Adult male survival probability (ϕ) was constant over time in our best-supported model. Our second-best-supported model indicated a negative effect of a 1998 ice storm on survival. The third-best-supported model indicated a significant year effect on survival. On the basis of those results and previously published estimates of annual fecundity, we calculated a population growth rate using a two-stage Leslie matrix. Population growth rate (λ) was 0.73, using the estimate for constant survival. Model elasticities imply that adult mortality had a stronger effect on λ than did seasonal fecundity. Oversummer survival estimates suggest that events during migration or on wintering grounds are responsible for most adult male mortality. It appears that our study population, thought to be one of the healthiest known for this species, may not be currently reproducing at a high enough rate to accommodate adult mortality. However, caution must be used when interpreting those results, given the possibility of underestimating survival and fecundity of this species.

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Population genetic structure and dispersal across a fragmented landscape in cerulean warblers (Dendroica cerulea)

Conservation Genetics ◽

10.1007/s10592-004-7831-9 ◽

2005 ◽

Vol 6 (2) ◽

pp. 159-174 ◽

Cited By ~ 39

Author(s):

M. L. Veit ◽

R. J. Robertson ◽

P. B. Hamel ◽

V. L. Friesen

Keyword(s):

Genetic Structure ◽

Population Genetic Structure ◽

Population Genetic ◽

Fragmented Landscape ◽

Dendroica Cerulea ◽

Cerulean Warblers

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Within-Territory Habitat Use and Microhabitat Selection by Male Cerulean Warblers (Dendroica Cerulea)

The Auk ◽

10.1093/auk/123.3.795 ◽

2006 ◽

Vol 123 (3) ◽

pp. 795-806 ◽

Cited By ~ 2

Author(s):

Jennifer J. Barg ◽

Deviah M. Aiama ◽

Jason Jones ◽

Raleigh J. Robertson

Keyword(s):

Management Strategies ◽

Space Use ◽

Habitat Characteristics ◽

Core Area ◽

Dendroica Cerulea ◽

Use Patterns ◽

Core Areas ◽

Song Transmission ◽

Cerulean Warblers ◽

And Function

Abstract Although most habitat characteristics are known to be continuously variable in space, practicality dictates that most habitat-selection studies at the spatial scale of the territory treat within-territory habitat as essentially homogeneous. However, the limitations associated with such a compromise have remained largely unexamined. Male Cerulean Warblers (Dendroica cerulea) exhibit nonrandom space- use patterns within their territories, in that all territories contain areas of intensive use or core areas. In addition to documenting territory-wide habitat and behavioral use patterns in this species, we asked two specific questions about core-area structure and function. (1) Are core-area habitats distinct in their vegetative composition and structure from the rest of the territory? (2) What behavioral mechanisms underlie the nonrandom space-use patterns? On a territory-wide basis, males used trees in proportion to their availability; however, core areas were predominantly composed of bitternut hickory (Carya cordiformis), which was a highly preferred song-post tree. Core areas were not consistently associated with any other habitat feature, including canopy gaps. Core areas were singing centers; song-post densities within core areas were 10× higher than in noncore areas. In our study area, bitternut hickories have significant delayed leaf-out patterns, potentially offering minimal acoustic hindrance to song transmission until late in the breeding season. These singing centers may be strategically placed to simultaneously maintain vigilance over social nests and maximize communication with conspecifics. Core areas are potentially as important to males as nesting habitat is to females, and their provision should be taken into account when implementing conservation or management strategies. Uso de Hábitat en los Territorios y Selección de Microhábitats por los Machos en Dendroica cerulea

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Post-fledging habitat use in a declining songbird

PeerJ ◽

10.7717/peerj.7358 ◽

2019 ◽

Vol 7 ◽

pp. e7358 ◽

Cited By ~ 2

Author(s):

Clayton D. Delancey ◽

Kamal Islam

Keyword(s):

Habitat Use ◽

Radio Telemetry ◽

Basal Area ◽

Vegetation Density ◽

White Oak ◽

Mature Trees ◽

Mature Forest ◽

Cerulean Warbler ◽

Migratory Songbird ◽

Cerulean Warblers

Background Fledglings of many mature forest-dependent Neotropical songbirds move from mature forest habitats into areas of thick vegetation such as regenerating clearcuts. The Cerulean Warbler (Setophaga cerulea), a Neotropical migratory songbird, is a species of conservation concern across its range and it is listed as endangered in Indiana. This species has declined faster than any other species of wood-warbler in North America. Most prior research on Cerulean Warblers has examined the breeding biology, but there are no data on habitat use by fledgling Cerulean Warblers. Our research aimed to determine where fledgling Cerulean Warblers dispersed after they left their nest, but before they migrated to their wintering grounds. Methods Since 2007, Cerulean Warbler breeding populations have been monitored in Yellowwood and Morgan–Monroe state forests in southern Indiana as part of a 100-year study called the Hardwood Ecosystem Experiment. To identify habitats used by fledgling Cerulean Warblers, we captured by hand or mist-nets, adult and juvenile Cerulean Warblers once young had fledged from a nest. We attached radio-transmitters to individuals and tracked each bird daily using radio-telemetry. Radio-telemetry data were collected from May to July 2015–2017, and microhabitat data on fledgling locations and random locations were collected during the same years in the month of July. Results Fledgling presence, when compared to random non-use sites, was positively correlated to presence of grapevines, greater vertical vegetation density, and greater ground and canopy cover. Fledgling presence was negatively correlated with white oak abundance, aspect, basal area, and the abundance of mature trees that Cerulean Warbler adults use for nesting. Conclusions Our study is the first to demonstrate that Cerulean Warbler fledglings occupy habitats that are characterized by specific habitat components. Fledgling sites were located in areas with high vegetation density, such as clusters of grapevine, which provided cover from predators. Identifying Cerulean Warbler habitats throughout the breeding season can better inform natural resource personnel on how to manage forests to meet the habitat needs of this rapidly declining migratory songbird.

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