GLobal Insect Threat-Response Synthesis (GLiTRS): a comprehensive and predictive assessment of the pattern and consequences of insect declines
Lead Research Organisation:
University of Cambridge
Department Name: Zoology
Abstract
With increasing recognition of the importance of insects, there are growing concerns that insect biodiversity has declined globally, with serious consequences for ecosystem function and services. Yet, gaps in knowledge limit progress in understanding the magnitude and direction of change. Information about insect trends is fragmented, and time-series data are restricted and unrepresentative, both taxonomically and spatially. Moreover, causal links between insect trends and anthropogenic pressures are not well-established. It is, therefore, difficult to evaluate stories about "insectageddon", to understand the ecosystem consequences, to devise mitigation strategies, or predict future trends.
To address the shortfalls, we will bring together diverse sources of information, such as meta-analyses, correlative relationships and expert judgement. GLiTRS will collate these diverse lines of evidence on how insect biodiversity has changed in response to anthropogenic pressures, how responses vary according to functional traits, over space, and across biodiversity metrics (e.g. species abundance, occupancy, richness and biomass), and how insect trends drive further changes (e.g. mediated by interaction networks).
We will integrate these lines of evidence into a Threat-Response model describing trends in insect biodiversity across the globe. The model will be represented in the form of a series of probabilistic statements (a Bayesian belief network) describing relationships between insect biodiversity and anthropogenic pressures.
By challenging this "Threat-Response model" to predict trends for taxa and places where high-quality time series data exist, we will identify insect groups and regions for which indirect data sources are a) sufficient for predicting recent trends, b) inadequate, or c) too uncertain. Knowledge about the predictability of threat-response relationships will allow projections - with uncertainty estimates - of how insect biodiversity has changed globally, across all major taxa, functional groups and biomes.
This global perspective on recent trends will provide the basis for an exploration of the consequences of insect decline for a range of ecosystem functions and services, as well as how biodiversity and ecosystem properties might be affected by plausible scenarios of future environmental change.
GLiTRS is an ambitious and innovative research program: two features are particularly ground-breaking. First, the collation of multiple forms of evidence will permit a truly global perspective on insect declines that is unachievable using conventional approaches. Second, by validating "prior knowledge" (from evidence synthesis) with recent trends, we will assess the degree to which insect declines are predictable, and at what scales.
To address the shortfalls, we will bring together diverse sources of information, such as meta-analyses, correlative relationships and expert judgement. GLiTRS will collate these diverse lines of evidence on how insect biodiversity has changed in response to anthropogenic pressures, how responses vary according to functional traits, over space, and across biodiversity metrics (e.g. species abundance, occupancy, richness and biomass), and how insect trends drive further changes (e.g. mediated by interaction networks).
We will integrate these lines of evidence into a Threat-Response model describing trends in insect biodiversity across the globe. The model will be represented in the form of a series of probabilistic statements (a Bayesian belief network) describing relationships between insect biodiversity and anthropogenic pressures.
By challenging this "Threat-Response model" to predict trends for taxa and places where high-quality time series data exist, we will identify insect groups and regions for which indirect data sources are a) sufficient for predicting recent trends, b) inadequate, or c) too uncertain. Knowledge about the predictability of threat-response relationships will allow projections - with uncertainty estimates - of how insect biodiversity has changed globally, across all major taxa, functional groups and biomes.
This global perspective on recent trends will provide the basis for an exploration of the consequences of insect decline for a range of ecosystem functions and services, as well as how biodiversity and ecosystem properties might be affected by plausible scenarios of future environmental change.
GLiTRS is an ambitious and innovative research program: two features are particularly ground-breaking. First, the collation of multiple forms of evidence will permit a truly global perspective on insect declines that is unachievable using conventional approaches. Second, by validating "prior knowledge" (from evidence synthesis) with recent trends, we will assess the degree to which insect declines are predictable, and at what scales.
People |
ORCID iD |
Lynn Dicks (Principal Investigator) |
Publications
Ashe-Jepson E
(2023)
Day-flying lepidoptera larvae have a poorer ability to thermoregulate than adults
in Ecology and Evolution
Ashe-Jepson E
(2023)
Day-flying Lepidoptera larvae have a poorer ability to thermoregulate than adults
Ashe-Jepson E
(2023)
Tropical butterflies use thermal buffering and thermal tolerance as alternative strategies to cope with temperature increase
in Journal of Animal Ecology
Ashe-Jepson E
(2023)
Day-flying lepidoptera larvae have a poorer ability to thermoregulate than adults.
Ashe-Jepson E
(2023)
Hot topics in butterfly research: Current knowledge and gaps in understanding of the impacts of temperature on butterflies
in Insect Conservation and Diversity
Bluethgen N
(2023)
Insect declines in the Anthropocene
Description | Work within the GLiTRS project has strengthened arguments for the use of predictive modelling to understand and mitigate future biodiversity change. We have been active within GEO BON and other networks in making the case for model-based indicators. GLiTRS has facilitated our contribution to the Grand Challenges in Entomology project, which is proving extremely influential in shaping the strategy of the Royal Entomological Society. |
First Year Of Impact | 2023 |
Sector | Education,Environment |
Impact Types | Societal Policy & public services |
Description | BBSRC Biodiversity Expert Working Group |
Geographic Reach | National |
Policy Influence Type | Participation in a guidance/advisory committee |
Description | Evidence to the UK House of Commons Science, Innovation and Technology Committee: Inquiry on insect decline and UK food security |
Geographic Reach | National |
Policy Influence Type | Contribution to a national consultation/review |
URL | https://committees.parliament.uk/work/7381/insect-decline-and-uk-food-security/ |
Description | Shaping Royal Entomological Society Strategic Priorities |
Geographic Reach | Multiple continents/international |
Policy Influence Type | Contribution to new or improved professional practice |
URL | https://www.royensoc.co.uk/grand-challenges-in-entomology-project/ |
Description | MEASURING ENVIRONMENTAL TOXINS ACTION LEGACY ON BEES |
Amount | £133,121 (GBP) |
Funding ID | NIF\R1\221715 |
Organisation | The Royal Society |
Sector | Charity/Non Profit |
Country | United Kingdom |
Start | 03/2023 |
End | 05/2025 |
Title | Regional differences in thermoregulation between two European butterfly communities |
Description | Understanding how different organisms cope with changing temperatures is vital for predicting future species' distributions and highlighting those at risk from climate change. As ectotherms, butterflies are sensitive to temperature changes, but the factors affecting butterfly thermoregulation are not fully understood. We investigated which factors influence thermoregulatory ability in a subset of a Mediterranean butterfly community. We measured adult thoracic temperature and environmental temperature (787 butterflies; 23 species) and compared buffering ability (defined as the ability to maintain a consistent body temperature across a range of air temperatures) and buffering mechanisms to previously published results from Great Britain. Finally, we tested whether thermoregulatory ability could explain species' demographic trends in Catalonia. The sampled sites in each region differ climatically, with higher temperatures and solar radiation but lower wind speeds in the Catalan sites. Both butterfly communities show nonlinear responses to temperature, suggesting a change in behaviour, from heat-seeking to heat avoidance, at approximately 22 °C. However, the communities differ in the use of buffering mechanisms, with British populations depending more on microclimates for thermoregulation compared to Catalan populations. Contrary to the results from British populations, we did not find a relationship between region-wide demographic trends and butterfly thermoregulation, which may be due to the interplay between thermoregulation and the habitat changes occurring in each region. Thus, although Catalan butterfly populations seem to be able to thermoregulate successfully at present, evidence of heat avoidance suggests this situation may change in the future. |
Type Of Material | Database/Collection of data |
Year Produced | 2023 |
Provided To Others? | Yes |
URL | https://datadryad.org/stash/dataset/doi:10.5061/dryad.rbnzs7hjk |
Title | Research data supporting "Regional differences in thermoregulation between two European butterfly communities" |
Description | Sampling was conducted at five sites in Catalonia, north-eastern Spain, consisting of a mixture of grassland and Mediterranean oak forest and comprising different altitudes (0-1,400 m above sea level), from March to September 2019 (22 days) and from March to October 2020 (23 days). Data were collected between 10:00 and 18:00, except for some occasional records outside this interval; the necessary permits were obtained from the Generalitat de Catalunya (record Nº SF/0048/2019 and SF/0086/2020). For Great Britain, data were collected from five calcareous grassland and three upland grassland localities, in summer 2009 and 2018. For details see Bladon et al. (2020). No ethical approval was required for this study. The same methods were used for collecting data in both regions to ensure comparability. Butterflies were searched for throughout the day at each site. When a butterfly was captured, its thoracic temperature (Tbody) was measured by touching a type-K thermocouple probe (TC direct, reference 406-477) attached to a handheld indicator (TC direct, reference 753-526) against the butterfly's thorax. Measurements were taken within 30 seconds of capture, while holding the butterfly in the net without directly touching it and keeping it in the shade, to minimise the effect of temperature changes inside the net. All nets were of a similar colour (approximately AMT-4 green or Hex #645d40) to minimise possible warming differences. Next, air temperature (Tair) was measured at waist height in the shade and, if the butterfly had been on a substrate before capture, air temperature approximately 2 cm above the substrate (microclimate temperature or Tmicrocl) was also measured. To estimate solar radiation experienced by the butterflies, we used the sum of beam normal irradiance (BNI) and diffuse horizontal irradiance (DHI) obtained from the Copernicus Atmosphere Monitoring Service (Schroedter-Homscheidt et al., 2022). BNI measures the radiation that arrives directly from the sun (i.e. without being scattered) at a surface perpendicular to the sunbeam. We chose BNI, instead of other measures of solar radiation, because butterflies can orient themselves to the sun to maximise the radiation they receive. DHI measures the radiation that arrives at a horizontal surface after being scattered by the atmosphere, which can be a considerable component of the radiation balance in some cases (Xie et al., 2021). These variables are interpolated from various input data at spatial resolutions from 3 to 5 km (CAMS; 2022). We downloaded data for each sampled site and month, measured as Wh/m2 over time windows of 1 minute. To estimate average forewing length for each species in Catalonia, a minimum of eight specimens per species were captured and taken to the laboratory. The butterflies were photographed using a standardised setup, consisting of a Canon EOS Rebel T2i DSLR camera attached to a Kaiser RS 2 CP copy stand (product reference KA5304), surrounded by a protective case made from white cardboard to provide a shield from external lighting. ImageJ software (Schneider et al., 2012) was used to measure forewing length, by drawing the outline of the forewing and measuring the longest line contained within it. An average was taken for each species or, in the case of sexually dimorphic species, for each species and sex. |
Type Of Material | Database/Collection of data |
Year Produced | 2023 |
Provided To Others? | Yes |
URL | https://www.repository.cam.ac.uk/handle/1810/361945 |
Description | E-perceptive project |
Organisation | Nokia Foundation |
Country | Finland |
Sector | Charity/Non Profit |
PI Contribution | We have started developing a low energy camera-based system to monitor insect biomass in real time, using computer vision, in partnership with the University of Cambridge Computing Labs. One postdoc has worked on this project for 13 months. |
Collaborator Contribution | Partners donated funding to support our research activities. |
Impact | A multidisciplinary collaboration involving computer scientists and ecologists. We are in the testing phase of a prototype for the E-Perceptive system. |
Start Year | 2023 |
Description | EntoGEM |
Organisation | University of Nevada |
Country | United States |
Sector | Academic/University |
PI Contribution | The GLiTRS team have built a relational database to store insect population time-series. We are providing a storage location for data generated by the EntoGEM team. Together we will create a global database of insect time-series. |
Collaborator Contribution | the EntoGEM project aims to create a Global Evidence Map (GEM) for insects. This is a database of studies, created from a systematic literature review, on insect population trends. The EntoGEM team have produced GEMs for two insect orders: Odonata and Lepidoptera. They are now in the process of extracting the data for Lepidoptera, which will be stored in the GLiTRS database. The two teams will work together to co-create (with GLiTRS) a meta-analysis of trends for this group. |
Impact | none yet |
Start Year | 2022 |
Description | Status of Insects: An International Research Coordination Network, funded by the US National Science Foundation |
Organisation | Insect Research Systems |
Country | United Kingdom |
Sector | Private |
PI Contribution | Lynn Dicks is a member of the Steering Group for the Status of Insect RCN, and leads the Working Group on Solutions. In collaboration with the RCN, we wrote a proposal for a Round Table discussion event at the forthcoming International Congress on Conservation Biology. This has been accepted, and will take place July 23-27, 2023, in Kigali, Rwanda. Title: Conservation of small things - how to incorporate insects (and other invertebrates) into the global biodiversity conservation agenda. The format will be six 12-minute presentations, each with 3 minutes for questions, plus a 1.5-hour Round Table discussion chaired by the Symposium Organiser. |
Collaborator Contribution | RCN is a network of US researchers on insect biodiversity. Members of the RCN organising committee supported our proposal for a Round Table event at a forthcoming international conference, and put forward one speaker. |
Impact | none yet |
Start Year | 2022 |
Description | University of Cambridge- UK Centre for Ecology and Hydrology |
Organisation | University of Cambridge |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | UKCEH is overall lead on the project, providing coordination across Work Packages |
Collaborator Contribution | Cambridge leads on the Expert elicitation elements of the project, and on the solutions package. Provides expert entomological expertise. |
Impact | none yet |
Start Year | 2020 |
Description | Evidence to Science, Innovation and Technology Committee, House of Commons |
Form Of Engagement Activity | A formal working group, expert panel or dialogue |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Policymakers/politicians |
Results and Impact | Oral and written evidence given to the 'Insect decline and UK food security' Inquiry. Event broadcast live on Parliament TV. |
Year(s) Of Engagement Activity | 2023 |
URL | https://committees.parliament.uk/work/7381/insect-decline-and-uk-food-security/ |
Description | Expert elicitation event at Ecological Society of America conference |
Form Of Engagement Activity | A formal working group, expert panel or dialogue |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Professional Practitioners |
Results and Impact | Experts were asked to rank threats to specific insect groups. |
Year(s) Of Engagement Activity | 2022 |
Description | Expert elicitation event at International Congress of Entomology |
Form Of Engagement Activity | A formal working group, expert panel or dialogue |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Professional Practitioners |
Results and Impact | Event to rank threats to specific insect orders |
Year(s) Of Engagement Activity | 2022 |
Description | More or Less World Service podcast Insect Decline interview |
Form Of Engagement Activity | A broadcast e.g. TV/radio/film/podcast (other than news/press) |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Public/other audiences |
Results and Impact | Prof Lynn Dicks was interviewed as part of an episode of the More of Less podcast about insect decline, as measured through splatted bugs on windscreens and number plates. |
Year(s) Of Engagement Activity | 2023 |
URL | https://www.bbc.co.uk/sounds/play/w3ct5b71 |
Description | Save Our Wild Isles: Hungry for Change documentary |
Form Of Engagement Activity | A broadcast e.g. TV/radio/film/podcast (other than news/press) |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Industry/Business |
Results and Impact | Inspired by Wild Isles, the iconic BBC nature documentary series, WWF, the RSPB, the National Trust and Silverback Films produced four films for businesses and organisations across the UK. Hungry for Change reveals the impact of the food system on nature in the UK and explores what actions businesses, employees, and farmers can take to reduce their impact. It includes interviews from leaders in the food and farming community, including Henry Dimbleby MBE (Author of the National Food Strategy) Tony Juniper CBE (Chair, Natural England), Ken Murphy (Group Chief Executive, Tesco), Dame Sharon White (Chairman, John Lewis Partnership), nature-friendly farmers like Patrick and David Barker (Lodge Farm) and Neil Heseltine (Hill Top Farm) and Professor Lynn Dicks form the University of Cambridge, on how businesses can help solve critical issues in the food system and put nature at the heart of their decision-making. Save Our Wild Isles: Hungry for Change is a 2023 winner of a Global Sustainability Film Award in the Greener Living category. By October 2023, the film had been seen by more than 17,000 employees at key businesses, including all Nestle staff. |
Year(s) Of Engagement Activity | 2023 |
URL | https://www.saveourwildisles.org.uk/business/food-and-farming |
Description | Talk to sixth form students and parents attending a Museum of Zoology summer school |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Schools |
Results and Impact | Gave a talk to students and their parents, at the end of a schools engagement week in which sixth form pupils curated an exhibition in the Museum of Zoology. Title: Pollinator decline: a case study of the need for transformative change to avert biodiversity loss. |
Year(s) Of Engagement Activity | 2023 |
Description | The Brain Hunters, El Cazador de Cerebros, Spanish TV Show |
Form Of Engagement Activity | A broadcast e.g. TV/radio/film/podcast (other than news/press) |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Public/other audiences |
Results and Impact | Prof Lynn Dicks featured in a popular Spanish TV science documentary series called 'El Cazador de Cerebros (The Brain Hunters)'. The episode was called 'Which species shall we save?' and aired on 24 April 2023. The interview was filmed in the Cambridge University Museum of Zoology, and discussed evidence-based conservation and the importance of conserving all species, even insects. |
Year(s) Of Engagement Activity | 2023 |
URL | https://www.rtve.es/play/videos/el-cazador-de-cerebros/especies-salvaremos/6873006/ |