Whole lake responses to species invasion mediated by climate change
Lead Research Organisation:
NERC CEH (Up to 30.11.2019)
Department Name: Parr
Abstract
Lake ecosystems face multiple stresses including nutrient enrichment, climate change and invasion of nonindigenous species. This latter stress is widely recognised as having a major impact on biodiversity and the functioning of ecosystems worldwide and its effects are increasing because human activity has enhanced rates of dispersal and climate change is opening new niches at high latitudes. Windermere, comprising two basins, is England's largest lake and one of the best studied in the world with detailed records extending back for up to 70 years. A marked deterioration in water quality has been observed in the last 10 to 15 years despite continued removal of a key nutrient, phosphorus, at the wastewater treatment works. For example, summer algal blooms have increased and concentrations of oxygen at depth have decreased. The numbers of the rare and protected fish, the Arctic charr, have also declined dramatically in recent years. These changes have coincided with the population expansion of a lower-latitude, nonindigenous species, the roach. In this project we will test the hypotheses that the roach expansion is a result of the documented warmer waters in Windermere and that the population increase has triggered a 'trophic cascade' leading to greater predation on the zooplankton, which in turn has reduced the algae from control by their grazer. We will also test whether the decline in Arctic charr numbers results from competition with roach, since both feed on the zooplankton. We are in a unique position to assess the long term ramifications of multiple stressors because of the wealth ecological and environmental data and preserved samples collected from Windermere for most of the last century. The project will involve targeted, detailed analysis of the long-term data, analysis of the historical archived fish and zooplankton samples, identification of food sources of the different fish populations and food-web structure using stable isotope analysis and studies of fish gut contents, hydroacoustic analysis to estimate fish density and location and modelling to estimate roach ecological niche, zooplankton grazing and algal growth. The project is relevant to current general ecological issues such as the importance of top-down-control, the effects of multiple stressors and possible species extinction caused by species invasion. The results will also be highly relevant to the management of lakes since if our hypotheses are correct, nutrient removal will need to be even more stringent in the face of climate change and disruption of food-chains caused by invasion of nonindigenous species.
Publications
WINFIELD I
(2012)
Long-term changes in the diet of pike (Esox lucius), the top aquatic predator in a changing Windermere Long-term changes in pike diet
in Freshwater Biology
Vindenes Y
(2014)
Effects of climate change on trait-based dynamics of a top predator in freshwater ecosystems.
in The American naturalist
Thackeray SJ
(2013)
Food web de-synchronization in England's largest lake: an assessment based on multiple phenological metrics.
in Global change biology
Smyntek P
(2012)
Dissolved carbon dioxide concentration controls baseline stable carbon isotope signatures of a lake food web
in Limnology and Oceanography
Simpson J
(2014)
Dissipation and mixing during the onset of stratification in a temperate lake, W indermere
in Limnology and Oceanography
Perga M
(2016)
A century of human-driven changes in the carbon dioxide concentration of lakes
in Global Biogeochemical Cycles
Ohlberger J
(2014)
When phenology matters: age-size truncation alters population response to trophic mismatch.
in Proceedings. Biological sciences
Elliott J
(2015)
Predicting the habitat expansion of the invasive roach Rutilus rutilus (Actinopterygii, Cyprinidae), in Great Britain
in Hydrobiologia
Description | Whole lake responses to species invasion mediated by climate change Ongoing analysis of long-term data and stable isotope analysis of long term archived material has shown substantial shifts in food web structure consequent on environmental perturbation in the two basins of Windermere. A new method to quantify size classes of preserved zooplankton samples has been developed and is being applied to the long-term samples to assess whether changes in fish populations can be linked to changes in zooplankton size-structure as hypothesised. A paper (Smyntek et al) used empirical and mechanistic models to produce a better method of accounting for changes in delta13C content of the baseline (zooplankton) populations by taking account of how the phytoplankton discriminate against delta 13C as a function of pH. This will improve estimate of baseline zooplankton delta 13C and hence improve estimates of foodweb interactions. |
Exploitation Route | The work highlighted the disruptive effect an expansion of a non-native species can have on lake water quality by triggering new trophic interactions. This is relevant to lake management as phosphorus reduction will need to be more severe in order to meet environmental targets. |
Sectors | Agriculture Food and Drink Environment |
Description | One day workshop exploring the lessons learnt from research on Windermere for practitioners concerned with effects of invasive species and climate change on lakes. Beneficiaries: Representatives from Environment Agency, Natural England, Natural Resources Wales, Scottish Natural Heritage and Cumbria Freshwater Invasive Non-Native Species attended and gave presentations. |
First Year Of Impact | 2013 |
Sector | Agriculture, Food and Drink,Environment |
Impact Types | Policy & public services |
Description | Nitrate Vulnerable Zones |
Geographic Reach | National |
Policy Influence Type | Participation in a guidance/advisory committee |
Impact | The work helped guide Defra decide which lakes should be in nitrate vulnerable zones in order to protect the environment, but taking into account the cost to the farming community. |
URL | https://www.gov.uk/guidance/nutrient-management-nitrate-vulnerable-zones |
Description | Cumbrian Lakes Research Forum |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Professional Practitioners |
Results and Impact | Over 40 delegates from 15 organisations attended to hear about the research being carried out on Cumbrian lakes from NERC funded grants. |
Year(s) Of Engagement Activity | 2015 |
Description | Guest lecture to students at Wolverhampton University |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Undergraduate students |
Results and Impact | Guest lecture on protected freshwater fish species |
Year(s) Of Engagement Activity | 2017 |
Description | Presentation at international conference |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Professional Practitioners |
Results and Impact | Presentation on effects of climate change at an international fisheries management conference. |
Year(s) Of Engagement Activity | 2017 |
Description | Presentation on lake research and monitoring to the U3A |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Public/other audiences |
Results and Impact | Presentation for about an hour to the University of the Third Age group in Cockermouth explaining the different types of monitoring and research that we undertake. |
Year(s) Of Engagement Activity | 2017 |
Description | Presentation to Environment Agency Fisheries practitioners |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Professional Practitioners |
Results and Impact | Seminar by Dr Ian Winfield to Environment Agency Fisheries practitioners. |
Year(s) Of Engagement Activity | 2017 |
Description | Presentation to West Cumbria Rivers Trust on the Arctic charr |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Regional |
Primary Audience | Public/other audiences |
Results and Impact | Presentation to the West Cumbria Rivers Trust on the Arctic charr |
Year(s) Of Engagement Activity | 2018 |
Description | Presentation to local natural history group on the Arctic charr |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Public/other audiences |
Results and Impact | Presentation to local natural history group on the Arctic charr in Windermere. |
Year(s) Of Engagement Activity | 2017 |