Biodiversity change & global change drivers
All around the world, populations and ecological communities are changing, creating a complex mix of increases, decreases or no changes in population abundance, species richness and species composition. The aim of my PhD is to find the mechanisms behind these heterogeneous patterns. Specifically, I am focusing on land-use change, habitat conversion and their interactions with climate warming which are thought to be the greatest drivers of change within ecosystems. By testing how human activities affect populations and biodiversity over time, we can quantify both immediate and temporally delayed impacts, which together allow us to predict how Earth’s biota will change across the Anthropocene.
Daskalova, G.N., Myers-Smith, I.H., Bjorkman, A.D., Blowes, S.A., Supp, S.R., Magurran, A., Dornelas M. (2018) Forest loss as a catalyst of population and biodiversity change. bioRxiv
The specific research questions I am addressing are:
1. Do rarity metrics and global change drivers explain variation in vertebrate population change?
2. How is land-use change influencing biodiversity change?
3. How are land-use intensification and land abandonment influencing biodiversity change?
4. How can we statistically attribute biodiversity change to global change drivers using big data in ecology?
Species pool & the landscape context of biodiversity change in the Arctic
The relationship between the regional species pool (all species present in a region) and local biodiversity trends, such as species turnover (the change in the species composition of a site over time) is a major research unknown for biology, particularly in the Arctic tundra, one of the biomes most sensitive to climate change. We are recording all the plant species we could find in two distinct vegetation communities on Qikiqtaruk-Herschel Island to determine how the regional species pool influences plant diversity at different landscape scales. Next, we will combine our ground observations with drone imagery to determine where across the tundra landscape we find the hotspots of biodiversity, and the source of potential future changes in plant community composition. This project is part of the larger ITEX network and our protocol is published on the Open Science Framework:
Rixen, C., Daskalova, G.N., Bjorkman, A.D., and Normand, S. (2019). Species Pool Protocol for the International Tundra Experiment Network (ITEX). Open Science Framework. DOI: 10.17605/OSF.IO/AGDFQ
In 2019, I am heading back to the Arctic to discover the tundra’s hidden biodiversity, supported by a National Geographic Early Career Grant. Our goal is to capture the species that are often missed by traditional small-scale monitoring and determine where across the landscape they are most often found. Linking across the plot and landscape scales, we will be able to make better predictions about how the Arctic’s biodiversity will be altered in a warmer climate.
Does rarity influence vertebrate population change?
(with Dr Isla Myers-Smith and John Godlee)
Understanding which factors predispose species to population change is essential for conservation decision-making. Around the world, populations are decreasing, increasing or remaining stable over time. Our goal was to determine if rarity explains these heterogeneous patterns across the planet.
Data publicly available from the Living Planet Database.
Species’ rarity and conservation status are often assumed to predict population change and thus inform conservation management. However, empirical tests of this assumption are lacking. Here we show that rarity and conservation status do not predict population change at UK and global scales, but species with smaller populations and larger ranges were more likely to fluctuate. We found taxonomic but not geographic patterning of population change among over 9000 populations from over 2000 vertebrate species, among which only amphibians experienced net declines. Our study suggests that with improved monitoring of diverse taxa and metrics beyond rarity, we can better inform conservation prioritization.
This research project started at a tutorial discussion group part of the Critical Thinking in Ecology honours course at the University of Edinburgh. You can read more about how we designed our project, as well as some of our key findings on the Critical Thinking blog.
Daskalova, G.N., Godlee, J.L., Myers-Smith, I.H. Rarity and conservation status do not predict vertebrate population trends. (in revision) Available on bioRxiv.
Tundra vegetation change
(Team Shrub collaborative research projects)
As part of my previous job as a lab and data manager for Team Shrub and now as a PhD student in the lab, I’m involved with some of Team Shrub’s collaborative research projects, including research on active layer depth changes on Qikiqtaruk-Herschel Island and how detection of vegetation attributes differs across scales, from field observations to drone imagery.
Myers-Smith, I.H., Grabowski, M., Thomas, H., Angers-Blondin, S., Daskalova, G.N., et al. Eighteen years of ecological monitoring reveals multiple lines of evidence for tundra vegetation change. (Accepted in Ecological Monographs, manuscript available on request)
Population responses of farmland bird species to agri-environment schemes and land management options in Northeastern Scotland
The decline of farmland birds in the UK is one of the most well-documented cases of biodiversity loss globally, and despite land stewardship supported by funding from agri-environment schemes (AES), the negative trends have not yet been reversed. To investigate AES contribution towards farmland conservation, we compared the rates of population change of five priority farmland bird species across 53 farms in Northeastern Scotland. We documented a weak effect size of participation in agri-environment schemes on farmland bird abundance, and recommend that future monitoring studies be designed after consulting a power analysis. Among different land management options, we found that species-rich grasslands, water margins and wetland creation enhanced breeding bird abundance, highlighting the importance of relatively undisturbed herbaceous or grassland vegetation for farmland conservation.
Daskalova, G. N., Phillimore, A. B., Bell, M., Maggs, H., & Perkins. A. J. (2018) Population responses of farmland bird species to agri‐environment schemes and land management options in Northeastern Scotland. Journal of Applied Ecology.