Loman, Z.G., A.P. Monroe, S.K. Riffell, D.A. Miller, F.J. Vilella, B.E. Wheat, S.A. Rush, and J.A. Martin. 2018. Nest Survival Modeling Using A Multi-Species Approach In Forests Managed For Timber And Biofuel Feedstock. Journal of Applied Ecology 55(2):937-946 10.1111/1365-2664.13015
Abstract
1. We analyzed nest data from a designed experiment to test for differences in habitat utility for 14 bird species in forest plots managed for biofuel feedstock production using switchgrass (Panicum virgatum) intercropping within a loblolly pine (Pinus taeda) plantation in Mississippi, USA.
2. We adapted hierarchical community models that use hyper-parameters to incorporate information from a suite of common and rare species to understand community-level nest survival. This approach incorporates information from rare species that are often discarded due to low sample sizes, but can inform community-level demographic parameters. We illustrate using this approach in generating both species-level and community-wide estimates of daily survival rates for songbird nests. We were able to include rare species with low sample size (minimum n = 4) to inform a community-level hyperprior, allowing us to estimate effects of nest placement covariates on daily survival at the community level, then compare this with a single-species approach using surrogate species.
3. Species-level survival and parameter estimates were similar to those generated by single species models, but estimates for species with low sample size may be unduly influenced by other species exhibiting varying survival responses to similar ecological conditions.
4. Covariates of nest placement indicated that presence of switchgrass at the nest site level (< 4 m) reduced daily nest survival, although intercropping at the forest stand level increased daily nest survival. Stand-level disturbances associated with establishing switchgrass and site-level microstructure may differentially promote or inhibit assemblages of nest predators within a diverse nest predator guild.
5. Synthesis and applications Hierarchical community models present a viable method for estimating community nest survival estimates and effects of covariates while incorporating limited data for rare, or rarely detected, species.