Periodic Reporting for period 1 - PinCER (Personality in Community Ecology Responses: Integrating the behaviour and species interactions of a marine invader)
Berichtszeitraum: 2020-01-13 bis 2022-01-12
This project used a unique and innovative combination of experimental and theoretical research, to analyse the role of behaviour and individual trait variation in biological invasions. Invasive species are a current risk to global biodiversity, particularly in marine systems where shipping has produced a massive influx of introduced species. Invasive species have enormous economic and ecological impacts on the communities that they invade, which demands a greater understanding of the processes driving invasions and invasive-species.
The overarching goal of this project way to disentangle the links between an animal’s behavioural traits and their interactions with other species. The experimental work aimed to analyse the invasive impacts of the round goby (Neogobius melanostomus) on aquatic communities in the Baltic Sea. By focusing on the round goby, a highly successful and damaging invader, this work provides important new data on the impacts of invasive species in northern Europe, as we as providing critical advances in our understanding of how individual traits influence the invasion process.
The three research-specific objectives are:
1. To quantify links between individual personality types of animals and their food-web interactions.
2. To concurrently assess variability in the behavioral trait composition and food-web interactions of round goby populations, across their invasion front.
3. To systematically analyze the evidence that individual trait variability (particularly behavioural variability), alters species interactions and community dynamics.
The overarching goal of this project way to disentangle the links between an animal’s behavioural traits and their interactions with other species. The experimental work aimed to analyse the invasive impacts of the round goby (Neogobius melanostomus) on aquatic communities in the Baltic Sea. By focusing on the round goby, a highly successful and damaging invader, this work provides important new data on the impacts of invasive species in northern Europe, as we as providing critical advances in our understanding of how individual traits influence the invasion process.
The three research-specific objectives are:
1. To quantify links between individual personality types of animals and their food-web interactions.
2. To concurrently assess variability in the behavioral trait composition and food-web interactions of round goby populations, across their invasion front.
3. To systematically analyze the evidence that individual trait variability (particularly behavioural variability), alters species interactions and community dynamics.
To address objectives 1 and 2, two Work Packages used an experimental approach to analyse behavioural and trophic variation in round goby populations within Danish waters along their invasion front. For the first Work Package, proof-of-concept pilot experiments were conducted in 2020, to test behavioural assays for analysing round goby traits in a well-established invasive population from Guldborgsund strait in Southern Denmark (54.69645N 11.84067E). These 2020 experiments showed that it is viable to analyse behavioural traits in wild fish alongside non-lethal methods to measure their food-web position (i.e. fin clips for stable isotope analysis). One publication from this package describing the behavioural experiments and their novel methodology is currently in preparation.
The second Work Package expanded on 2020’s experiments, by using the same experimental approach at four sites along 100 km of the round goby’s invasion front, from Dragør near the invasion front (55.58034N 12.65598E) to Grønsund a well-established population in southern Denmark (54.90371N 12.10367E). This work successfully sampled four round goby populations in May 2021, so that their behavioural traits, physiological variation and food web position could be analysed. Final data analysis on this major experimental program is still underway, with preliminary results suggesting that there significant within-species variation in behavioural traits and food-web position across their invasion front. The major publication from this work is currently in preparation, and a second publication analysing the impacts of round goby feeding on benthic fauna in Guldborgsund has been published (van Deurs, Moran et al. 2021, NeoBiota doi:10.3897/neobiota.68.67340). A Master’s student project was also conducted as part of this work package (Thesis “The effects of behavioural and physiological variation on the spread of a marine invasive fish / the round goby”, Andrea Galli, to be submitted Feb 2022), and a third manuscript is also expected to be produced based on this Master's project.
To address objective 3, the third Work Package in this project used systematic review and meta-analysis methods to review existing literature and analyse how individual trait variation can alter the outcome of ecological interactions. Given the major interruptions to experimental work in this project due to COVID, more focus was placed on this theoretical work than initially expected, and multiple publications have resulted from this Work Package. The main study was a systematic synthesis review, focusing on how individual trait variation can influence the outcome of ecological interactions. This collected information from 96 studies showing qualitative shifts in ecological interactions driven by individual variation, and described a new framework for understanding how these processes occur. This was recently published, and selected as a ‘Editor’s Choice’ paper in the journal Oikos (Moran et al. 2021, Oikos doi:10.1111/oik.08201). Additional systematic review studies that have been published under the Work Package are: a large meta-analysis focusing on the effects of diet on risk-taking behavioural traits in animals (Moran et al. 2020, Biol Revs, doi:10.1111/brv.12655); a methodological paper focusing on the use of statistical approaches to analyse effects on trait variance in meta-analyses (Sánchez‐Tójar, Moran et al. 2020, J Evol Biol, doi:10.1111/jeb.13661); and a meta-analysis on body size trait variation of male-female interactions in the invasive mosquitofish (Kim, Moran et al. 2021, J Anim Ecol doi:10.1111/1365-2656.13554; led by Master’s student Bora Kim, Bielefeld University).
The second Work Package expanded on 2020’s experiments, by using the same experimental approach at four sites along 100 km of the round goby’s invasion front, from Dragør near the invasion front (55.58034N 12.65598E) to Grønsund a well-established population in southern Denmark (54.90371N 12.10367E). This work successfully sampled four round goby populations in May 2021, so that their behavioural traits, physiological variation and food web position could be analysed. Final data analysis on this major experimental program is still underway, with preliminary results suggesting that there significant within-species variation in behavioural traits and food-web position across their invasion front. The major publication from this work is currently in preparation, and a second publication analysing the impacts of round goby feeding on benthic fauna in Guldborgsund has been published (van Deurs, Moran et al. 2021, NeoBiota doi:10.3897/neobiota.68.67340). A Master’s student project was also conducted as part of this work package (Thesis “The effects of behavioural and physiological variation on the spread of a marine invasive fish / the round goby”, Andrea Galli, to be submitted Feb 2022), and a third manuscript is also expected to be produced based on this Master's project.
To address objective 3, the third Work Package in this project used systematic review and meta-analysis methods to review existing literature and analyse how individual trait variation can alter the outcome of ecological interactions. Given the major interruptions to experimental work in this project due to COVID, more focus was placed on this theoretical work than initially expected, and multiple publications have resulted from this Work Package. The main study was a systematic synthesis review, focusing on how individual trait variation can influence the outcome of ecological interactions. This collected information from 96 studies showing qualitative shifts in ecological interactions driven by individual variation, and described a new framework for understanding how these processes occur. This was recently published, and selected as a ‘Editor’s Choice’ paper in the journal Oikos (Moran et al. 2021, Oikos doi:10.1111/oik.08201). Additional systematic review studies that have been published under the Work Package are: a large meta-analysis focusing on the effects of diet on risk-taking behavioural traits in animals (Moran et al. 2020, Biol Revs, doi:10.1111/brv.12655); a methodological paper focusing on the use of statistical approaches to analyse effects on trait variance in meta-analyses (Sánchez‐Tójar, Moran et al. 2020, J Evol Biol, doi:10.1111/jeb.13661); and a meta-analysis on body size trait variation of male-female interactions in the invasive mosquitofish (Kim, Moran et al. 2021, J Anim Ecol doi:10.1111/1365-2656.13554; led by Master’s student Bora Kim, Bielefeld University).
By analysing behavioural and food-web variation across a species’ invasion front, the experimental work within this represents an important technical advance in how we analyse individual variation in nature. Each individual animal has their own specific set of traits, and individual differences in behavioural traits (or personality) is both very common in animals and can have profound impacts on how an individual interacts with their environment. Methods that can analyse both trait variation in live animals, and concurrently use non-lethal methods (i.e. stable isotope analysis) to analyse food-web variation are a novel and important next step in behavioural ecology research in general. In addition, analysing individual variation using these methods along an invasion front in unprecedented and will provide important new insight into the ecology and impacts of the invasive round goby. Four publications are anticipated to result from this experimental work (of which one has already been published; van Deurs, Moran et al. 2021, NeoBiota), which together will have an important role in directing future research in behavioural ecology and invasion biology.
The four theoretical/systematic review based publications linked to this project each analyse important aspects of the relationship between individual variation and ecological interactions, and represent an important new body of work in behavioural ecology. For example, Moran et al. (2021, Oikos) provides a framework for understanding how individual trait variation impacts the outcomes ecological interactions generally. This framework is relevant to our study system of round gobies and their impacts on Baltic Sea communities, but also has broad significance across research fields within ecology, including those that focus on predator-prey, male-female, plant-animal, host-symbiont and social interactions, so represents an important conceptual advance in ecology generally. In sum, this project provides both important experimental and conceptual advances in behavioural ecology and invasion biology, by using novel experimental methods and advanced systematic review approaches to studying individual variation in nature.
The four theoretical/systematic review based publications linked to this project each analyse important aspects of the relationship between individual variation and ecological interactions, and represent an important new body of work in behavioural ecology. For example, Moran et al. (2021, Oikos) provides a framework for understanding how individual trait variation impacts the outcomes ecological interactions generally. This framework is relevant to our study system of round gobies and their impacts on Baltic Sea communities, but also has broad significance across research fields within ecology, including those that focus on predator-prey, male-female, plant-animal, host-symbiont and social interactions, so represents an important conceptual advance in ecology generally. In sum, this project provides both important experimental and conceptual advances in behavioural ecology and invasion biology, by using novel experimental methods and advanced systematic review approaches to studying individual variation in nature.