Density-dependent and density-independent effects on outbreak dynamics in an invasive forest insect
Several bark and wood-boring insects exhibit eruptive population dynamics during which declining host vigor triggers rapid insect population growth and widespread tree mortality. The invasive woodwasp Sirex noctilio F. (Hymenoptera: Siricidae) is typically considered a semi-aggressive species due to...
| Autores principales: | , , , |
|---|---|
| Formato: | Artículo |
| Lenguaje: | Inglés |
| Publicado: |
Springer
2026
|
| Materias: | |
| Acceso en línea: | http://hdl.handle.net/20.500.12123/24919 https://link.springer.com/article/10.1007/s10340-025-02006-w https://doi.org/10.1007/s10340-025-02006-w |
| _version_ | 1855487423777079296 |
|---|---|
| author | Villacide, Jose Maria Liebhold, Andrew M. Cavigliasso, Pablo Corley, Juan Carlos |
| author_browse | Cavigliasso, Pablo Corley, Juan Carlos Liebhold, Andrew M. Villacide, Jose Maria |
| author_facet | Villacide, Jose Maria Liebhold, Andrew M. Cavigliasso, Pablo Corley, Juan Carlos |
| author_sort | Villacide, Jose Maria |
| collection | INTA Digital |
| description | Several bark and wood-boring insects exhibit eruptive population dynamics during which declining host vigor triggers rapid insect population growth and widespread tree mortality. The invasive woodwasp Sirex noctilio F. (Hymenoptera: Siricidae) is typically considered a semi-aggressive species due to the absence of aggregation pheromones and a strong dependence on density-independent factors. However, in many parts of its invaded range, S. noctilio displays pronounced outbreaks and spatial aggregation, suggesting more complex population mechanisms. We hypothesized that S. noctilio behaves as an aggressive forest insect in its invaded range, where population dynamics are driven by a combination of both density-independent (host condition) and density-dependent (population density) mechanisms. To test this, we conducted a field experiment in an invaded region, where host susceptibility was manipulated using herbicide-induced stress, and local population density was assessed by selecting plantations with contrasting wasp densities. We jointly investigated the effects of these factors on female host selection and offspring performance. We found that host stress strongly influenced female host selection, whereas local population density had little influence on the probability of attack. In contrast, larval performance was largely unaffected by host stress but exhibited positive density-dependent effects, with more and larger individuals emerging from trees in plantations with higher S. noctilio population densities. These positive density-dependent responses are inherently destabilizing and likely contribute to the pattern of eruptive population dynamics seen in invasive populations of this forest insect. |
| format | Artículo |
| id | INTA24919 |
| institution | Instituto Nacional de Tecnología Agropecuaria (INTA -Argentina) |
| language | Inglés |
| publishDate | 2026 |
| publishDateRange | 2026 |
| publishDateSort | 2026 |
| publisher | Springer |
| publisherStr | Springer |
| record_format | dspace |
| spelling | INTA249192026-01-07T13:10:17Z Density-dependent and density-independent effects on outbreak dynamics in an invasive forest insect Villacide, Jose Maria Liebhold, Andrew M. Cavigliasso, Pablo Corley, Juan Carlos Plagas Forestales Dinámica de Poblaciones Especie Invasiva Forest Pests Sirex Population Dynamics Invasive Species Sirex noctilio Región Patagónica Several bark and wood-boring insects exhibit eruptive population dynamics during which declining host vigor triggers rapid insect population growth and widespread tree mortality. The invasive woodwasp Sirex noctilio F. (Hymenoptera: Siricidae) is typically considered a semi-aggressive species due to the absence of aggregation pheromones and a strong dependence on density-independent factors. However, in many parts of its invaded range, S. noctilio displays pronounced outbreaks and spatial aggregation, suggesting more complex population mechanisms. We hypothesized that S. noctilio behaves as an aggressive forest insect in its invaded range, where population dynamics are driven by a combination of both density-independent (host condition) and density-dependent (population density) mechanisms. To test this, we conducted a field experiment in an invaded region, where host susceptibility was manipulated using herbicide-induced stress, and local population density was assessed by selecting plantations with contrasting wasp densities. We jointly investigated the effects of these factors on female host selection and offspring performance. We found that host stress strongly influenced female host selection, whereas local population density had little influence on the probability of attack. In contrast, larval performance was largely unaffected by host stress but exhibited positive density-dependent effects, with more and larger individuals emerging from trees in plantations with higher S. noctilio population densities. These positive density-dependent responses are inherently destabilizing and likely contribute to the pattern of eruptive population dynamics seen in invasive populations of this forest insect. EEA Bariloche Fil: Villacide, José. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche. Instituto de Investigaciones Forestales y Agropecuarias Bariloche (IFAB). Grupo de Ecología de Poblaciones de Insectos; Argentina Fil: Villacide, José. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Forestales y Agropecuarias Bariloche (IFAB). Grupo de Ecología de Poblaciones de Insectos; Argentina; Argentina Fil: Liebhold, Andrew. Czech University of Life Sciences. Faculty of Forestry and Wood Sciences; República Checa Fil: Liebhold, Andrew. US Forest Service. Northern Research Station; Estados Unidos Fil: Cavigliasso, Pablo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Marcos Juárez; Argentina Fil: Corley, Juan Carlos. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche. Instituto de Investigaciones Forestales y Agropecuarias Bariloche (IFAB). Grupo de Ecología de Poblaciones de Insectos; Argentina Fil: Corley, Juan Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Forestales y Agropecuarias Bariloche (IFAB). Grupo de Ecología de Poblaciones de Insectos; Argentina Fil: Corley, Juan Carlos. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche. Departamento de Ecología; Argentina 2026-01-07T13:06:36Z 2026-01-07T13:06:36Z 2026-01 info:ar-repo/semantics/artículo info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion http://hdl.handle.net/20.500.12123/24919 https://link.springer.com/article/10.1007/s10340-025-02006-w 1612-4758 1612-4766 https://doi.org/10.1007/s10340-025-02006-w eng info:eu-repograntAgreement/INTA/2019-PD-E1-I600-001, Bioecología y estrategias de manejo de organismos perjudiciales y benéficos en escenarios de intensificación sustentable de cultivos info:eu-repograntAgreement/INTA/2023-PD-L01-I074, Bases ecológicas y epidemiológicas para el diseño de estrategias de manejo de plagas agrícolas y forestales info:eu-repo/semantics/reference/hdl/20.500.12123/19663 info:eu-repo/semantics/restrictedAccess http://creativecommons.org/licenses/by-nc-sa/4.0/ Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) application/pdf Springer Journal of Pest Science 99 : article number 3. (2026) |
| spellingShingle | Plagas Forestales Dinámica de Poblaciones Especie Invasiva Forest Pests Sirex Population Dynamics Invasive Species Sirex noctilio Región Patagónica Villacide, Jose Maria Liebhold, Andrew M. Cavigliasso, Pablo Corley, Juan Carlos Density-dependent and density-independent effects on outbreak dynamics in an invasive forest insect |
| title | Density-dependent and density-independent effects on outbreak dynamics in an invasive forest insect |
| title_full | Density-dependent and density-independent effects on outbreak dynamics in an invasive forest insect |
| title_fullStr | Density-dependent and density-independent effects on outbreak dynamics in an invasive forest insect |
| title_full_unstemmed | Density-dependent and density-independent effects on outbreak dynamics in an invasive forest insect |
| title_short | Density-dependent and density-independent effects on outbreak dynamics in an invasive forest insect |
| title_sort | density dependent and density independent effects on outbreak dynamics in an invasive forest insect |
| topic | Plagas Forestales Dinámica de Poblaciones Especie Invasiva Forest Pests Sirex Population Dynamics Invasive Species Sirex noctilio Región Patagónica |
| url | http://hdl.handle.net/20.500.12123/24919 https://link.springer.com/article/10.1007/s10340-025-02006-w https://doi.org/10.1007/s10340-025-02006-w |
| work_keys_str_mv | AT villacidejosemaria densitydependentanddensityindependenteffectsonoutbreakdynamicsinaninvasiveforestinsect AT liebholdandrewm densitydependentanddensityindependenteffectsonoutbreakdynamicsinaninvasiveforestinsect AT cavigliassopablo densitydependentanddensityindependenteffectsonoutbreakdynamicsinaninvasiveforestinsect AT corleyjuancarlos densitydependentanddensityindependenteffectsonoutbreakdynamicsinaninvasiveforestinsect |