Budworm-linked warblers as early indicators of defoliation by spruce budworm: A field study
Outbreaks of eastern spruce budworm (Choristoneura fumiferana; hereafter SBW) are a major natural disturbance in coniferous forests of eastern North America. These outbreaks provide a superabundant source of food for insectivorous birds. Three species, referred to as budworm-linked warblers, exhibit...
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| Format: | Article |
| Language: | English |
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Elsevier
2021-06-01
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| Series: | Ecological Indicators |
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S1470160X21002089 |
| _version_ | 1818843827232833536 |
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| author | Jeanne Moisan Perrier Daniel Kneeshaw Martin-Hugues St-Laurent Peter Pyle Marc-André Villard |
| author_facet | Jeanne Moisan Perrier Daniel Kneeshaw Martin-Hugues St-Laurent Peter Pyle Marc-André Villard |
| author_sort | Jeanne Moisan Perrier |
| collection | DOAJ |
| description | Outbreaks of eastern spruce budworm (Choristoneura fumiferana; hereafter SBW) are a major natural disturbance in coniferous forests of eastern North America. These outbreaks provide a superabundant source of food for insectivorous birds. Three species, referred to as budworm-linked warblers, exhibit strong positive numerical responses to early increases of SBW density: Tennessee Warbler (Leiothlypis peregrina), Cape May Warbler (Setophaga tigrina), and Bay-breasted Warbler (S. castanea). Their abundance increases even before defoliation is visible from aerial surveys. Budworm-linked warblers may detect new epicenters of SBW outbreaks through natal dispersal, as this movement is typically much more extensive than subsequent (breeding dispersal) movements. Our main objectives were, thus, (1) to determine whether sudden increases in the abundance of budworm-linked warblers could be used to detect early stages of SBW outbreaks, and (2) to examine age-specific responses of budworm-linked warblers to local and landscape-level habitat characteristics, in order to investigate the potential role of natal dispersal in the detection of new epicenters. To do so, we estimated the abundance of each species of budworm-linked warbler in 75 study plots sampling a gradient of SBW density and related them to 7 stand variables and landscape metrics with generalized additive mixed models. We also compared the responses of yearling (second-year; SY) and older (after-second-year; ASY) individuals to the density of SBW larvae and habitat variables at different spatial scales. We captured 31 Tennessee Warblers, 27 Cape May Warblers, and 57 Bay-breasted Warblers. The abundance of all three species of budworm-linked warblers increased with SBW larval density, but the numerical response of Bay-breasted Warbler was initiated earlier and it varied with age. SY individuals tended to be associated with stands supporting lower larval densities than ASY individuals and, as suggested by other authors, Bay-breasted Warbler appeared to be more efficient at exploiting SBW larvae at low density. For that reason, this species represents an early indicator of stands undergoing SBW outbreaks and we propose to use its abundance as an indicator to orient labour-intensive ground surveys of SBW larvae. |
| first_indexed | 2024-12-19T05:04:03Z |
| format | Article |
| id | doaj.art-95ad74b0756b4a33a5489329d790c006 |
| institution | Directory Open Access Journal |
| issn | 1470-160X |
| language | English |
| last_indexed | 2024-12-19T05:04:03Z |
| publishDate | 2021-06-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Ecological Indicators |
| spelling | doaj.art-95ad74b0756b4a33a5489329d790c0062022-12-21T20:35:00ZengElsevierEcological Indicators1470-160X2021-06-01125107543Budworm-linked warblers as early indicators of defoliation by spruce budworm: A field studyJeanne Moisan Perrier0Daniel Kneeshaw1Martin-Hugues St-Laurent2Peter Pyle3Marc-André Villard4Département de biologie, chimie et géographie, Centre d’étude de la forêt, Université du Québec à Rimouski, 300 Allée des Ursulines, Rimouski, Québec G5L 3A1, CanadaDépartement des sciences biologiques, Centre d’étude de la forêt, Université du Québec à Montréal, 141 Avenue du Président-Kennedy, Montréal, Québec H2X 1Y4, CanadaDépartement de biologie, chimie et géographie, Centre d’étude de la forêt, Université du Québec à Rimouski, 300 Allée des Ursulines, Rimouski, Québec G5L 3A1, CanadaInstitute for Bird Populations, Petaluma, CA 94953, USADépartement de biologie, chimie et géographie, Centre d’étude de la forêt, Université du Québec à Rimouski, 300 Allée des Ursulines, Rimouski, Québec G5L 3A1, Canada; Department of Biology, Mount Allison University, 62 York St, Sackville, New Brunswick E4L 1E2, Canada; Corresponding author at: Sépaq, 5176 rue Fabre, Montréal, Québec H2J 3W5, Canada.Outbreaks of eastern spruce budworm (Choristoneura fumiferana; hereafter SBW) are a major natural disturbance in coniferous forests of eastern North America. These outbreaks provide a superabundant source of food for insectivorous birds. Three species, referred to as budworm-linked warblers, exhibit strong positive numerical responses to early increases of SBW density: Tennessee Warbler (Leiothlypis peregrina), Cape May Warbler (Setophaga tigrina), and Bay-breasted Warbler (S. castanea). Their abundance increases even before defoliation is visible from aerial surveys. Budworm-linked warblers may detect new epicenters of SBW outbreaks through natal dispersal, as this movement is typically much more extensive than subsequent (breeding dispersal) movements. Our main objectives were, thus, (1) to determine whether sudden increases in the abundance of budworm-linked warblers could be used to detect early stages of SBW outbreaks, and (2) to examine age-specific responses of budworm-linked warblers to local and landscape-level habitat characteristics, in order to investigate the potential role of natal dispersal in the detection of new epicenters. To do so, we estimated the abundance of each species of budworm-linked warbler in 75 study plots sampling a gradient of SBW density and related them to 7 stand variables and landscape metrics with generalized additive mixed models. We also compared the responses of yearling (second-year; SY) and older (after-second-year; ASY) individuals to the density of SBW larvae and habitat variables at different spatial scales. We captured 31 Tennessee Warblers, 27 Cape May Warblers, and 57 Bay-breasted Warblers. The abundance of all three species of budworm-linked warblers increased with SBW larval density, but the numerical response of Bay-breasted Warbler was initiated earlier and it varied with age. SY individuals tended to be associated with stands supporting lower larval densities than ASY individuals and, as suggested by other authors, Bay-breasted Warbler appeared to be more efficient at exploiting SBW larvae at low density. For that reason, this species represents an early indicator of stands undergoing SBW outbreaks and we propose to use its abundance as an indicator to orient labour-intensive ground surveys of SBW larvae.http://www.sciencedirect.com/science/article/pii/S1470160X21002089Boreal forestDespotic behaviorDispersalHerbivorous insectsEarly intervention strategiesInsect outbreaks |
| spellingShingle | Jeanne Moisan Perrier Daniel Kneeshaw Martin-Hugues St-Laurent Peter Pyle Marc-André Villard Budworm-linked warblers as early indicators of defoliation by spruce budworm: A field study Ecological Indicators Boreal forest Despotic behavior Dispersal Herbivorous insects Early intervention strategies Insect outbreaks |
| title | Budworm-linked warblers as early indicators of defoliation by spruce budworm: A field study |
| title_full | Budworm-linked warblers as early indicators of defoliation by spruce budworm: A field study |
| title_fullStr | Budworm-linked warblers as early indicators of defoliation by spruce budworm: A field study |
| title_full_unstemmed | Budworm-linked warblers as early indicators of defoliation by spruce budworm: A field study |
| title_short | Budworm-linked warblers as early indicators of defoliation by spruce budworm: A field study |
| title_sort | budworm linked warblers as early indicators of defoliation by spruce budworm a field study |
| topic | Boreal forest Despotic behavior Dispersal Herbivorous insects Early intervention strategies Insect outbreaks |
| url | http://www.sciencedirect.com/science/article/pii/S1470160X21002089 |
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