Background: Although pelagic seabirds are broadly recognised as indicators of the health of marine systems, numerous gaps exist in knowledge of their at-sea distributions at the species level. These gaps have profound negative impacts on the robustness of marine conservation policies. Correlative modelling techniques have provided some information, but few studies have explored model development for non-breeding pelagic seabirds. Here, I present a first phase in developing robust niche models for highly mobile species as a baseline for further development. Methodology: Using observational data from a 12-year time period, 217 unique model parameterisations across three correlative modelling algorithms (boosted regression trees, Maxent and minimum volume ellipsoids) were tested in a time-averaged approach for their ability to recreate the at-sea distribution of non-breeding Wandering Albatrosses (Diomedea exulans) to provide a baseline for further development. Principle Findings/Results: Overall, minimum volume ellipsoids outperformed both boosted regression trees and Maxent. However, whilst the latter two algorithms generally overfit the data, minimum volume ellipsoids tended to underfit the data. Conclusions: The results of this exercise suggest a necessary evolution in how correlative modelling for highly mobile species such as pelagic seabirds should be approached. These insights are crucial for understanding seabird-environment interactions at macroscales, which can facilitate the ability to address population declines and inform effective marine conservation policy in the wake of rapid global change. ABSTRACT Boosted regression trees; digital accessible knowledge; distribution modelling; Maxent; minimum volume ellipsoids; pelagic seabird distribution; Diomedea exulans KEYWORDS
Assisted migration of warm-adapted genotypes to currently cooler climates may reduce maladaptation from future climate change. Few assisted migration trials have considered limitations of the cooler climates and pathogens currently present at transplant sites. This is especially important to consider in riparian ecosystems that are priority targets for restoration in the western United States as they harbor diverse communities. In an effort to validate assisted migration as an effective strategy for mediating the negative impacts of climate change, we used a provenance trial with replicated genotypes from 19 populations of the foundation riparian tree species, Fremont cottonwood (Populus fremontii), transplanted to a cold site to test for genetic variation in growth, mortality, and resistance to shoot blight fungi (Venturia sp.). Populations from cool sites had up to 4 times faster growth, 3 times higher survival, and 8 times higher resistance to Venturia than populations from warm sites, providing evidence of local adaptation to both climate and pathogenic fungi. Budburst phenology and shoot blight were correlated with frost damage, subsequent shrub-form architecture, and mortality. While climate change models predict 6 ∘ C increases, plants transferred distances of 6 ∘ C at this time would not perform well; an intermediate transfer distance of less than 3 ∘ C would avoid maladaptation to the current environment during assisted migration. Thus, multiple and intermediate transfer phases to supplement local genetic variation will likely be necessary for effective assisted migration to accommodate current environments and large changes in climate.
Summary 1.Although the genetics of foundation plant species is known to be important drivers of biodiversity and community structure, and climate change is known to have ecological and evolutionary consequences for plants, no studies have integrated these concepts. Here we examine how their combined effects are likely to affect the diversity of future communities. 2. We draw on several complimentary fields (community ecology, landscape genetics and biogeography) to model how climate change will alter productivity of foundation plant species and their associated communities. We focus on three issues: (i) genetic variation of foundation species influences community diversity; (ii) gene-by-environment interactions define associated communities; and (iii) relationships between productivity and species diversity follow predictable patterns. 3. For many foundation species, responses to climate are population specific because populations are often genetically differentiated and locally adapted. Thus, biological models that examine the effects of climate change on species distribution, forest productivity, community structure or function, should incorporate population effects. Our genetics-based Universal Community Transfer Function (UCTF) provides a method to integrate climate-based population differences into community diversity models. 4. Several major findings emerged: (i) using the UCTF, we found that genetics-based differences between populations play an important role in defining future communities. (ii) The shape of the productivity/diversity relationship (e.g. humpbacked versus linear) dramatically affects future communities making it essential to quantify this relationship. (iii) Climate change will impact the community differently at leading, continuous and rear edges of a species' distribution, but diversity at the rear edge will suffer most. 5. Genetics-based approaches are important to understand the ecological and evolutionary consequences of climate change on future communities and ecosystems. Such modelling can assist in identifying populations of foundation species of special value based on their sensitivity to climate change, future biodiversity and potential to support high biodiversity with assisted migration.
We examined the impact climate change (CC) will have on the availability of climatically suitable habitat for three native and one exotic riparian species. Due to its increasing prevalence in arid regions throughout the western US, we predicted that an exotic species, Tamarix, would have the greatest increase in suitable habitat relative to native counterparts under CC. We used an ecological niche model to predict range shifts of Populus fremontii, Salix gooddingii, Salix exigua and Tamarix, from present day to 2080s, under five general circulation models and one climate change scenario (A1B). Four major findings emerged. 1) Contrary to our original hypothesis, P. fremontii is projected to have the greatest increase in suitable habitat under CC, followed closely by Tamarix. 2) Of the native species, S. gooddingii and S. exigua showed the greatest loss in predicted suitable habitat due to CC. 3) Nearly 80 percent of future P. fremontii and Salix habitat is predicted to be affected by either CC or Tamarix by the 2080s. 4) By the 2080s, 20 percent of S. gooddingii habitat is projected to be affected by both Tamarix and CC concurrently, followed by S. exigua (19 percent) and P. fremontii (13 percent). In summary, while climate change alone will negatively impact both native willow species, Tamarix is likely to affect a larger portion of all three native species' distributions. We discuss these and other results in the context of prioritizing restoration and conservation efforts to optimize future productivity and biodiversity. As we are accounting for only direct effects of CC and Tamarix on native habitat, we present a possible hierarchy of effects- from the direct to the indirect- and discuss the potential for the indirect to outweigh the direct effects. Our results highlight the need to account for simultaneous challenges in the face of CC.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.