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Insect declines are being reported worldwide and private, residential gardens could provide refugia for these species under increasing land use change. Interest in wildlife-friendly gardening has increased, but many management recommendations lack a scientific evidence-base. We used a large citizen science scheme, the Garden Butterfly Survey (GBS), with data from over 600 gardens across Great Britain (2016-2021) to determine how the surrounding landscape influences the abundance and species richness of butterflies in gardens and whether wildlife-friendly gardening practices, such as having long grass and providing nectar plants, benefit butterflies. First, we show that GBS provides reliable estimates of species abundances by comparing with results from standardised, long-term monitoring data. Garden size and surrounding land use had significant effects on butterfly abundance and richness in gardens, including positive relationships with garden size, woodland and arable farmland and negative relationships with urbanisation. Both the presence and area of long grass in gardens were positively related to higher butterfly richness and abundance, with the latter being driven by butterflies that use grasses as larval host plants. These effects differed depending on the surrounding landscape, such that long grass resulted in higher garden butterfly abundance in landscapes dominated by arable farming, and higher abundance and richness in highly urbanised areas. The presence of flowering ivy (Hedera spp.) in gardens resulted in higher abundance of Celastrina argiolus holly blue which uses ivy as a larval host, and of Vanessa atalanta red admiral and Polygonia c-album comma, which favour it as a nectar source. Our work provides evidence that undertaking simple wildlife-friendly garden practices can be beneficial for attracting butterflies, particularly in heavily modified areas. With over 728,000 ha of gardens in Great Britain, the cumulative effect of leaving areas of lawn uncut and providing nectar and larval host plants could be key for helping biodiversity., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Since widespread monitoring began in 1976 in the UK, habitat‐specialist butterfly populations have declined dramatically. The main driver is habitat degradation, caused primarily by land‐use change, perhaps interacting with changes in vegetation phenology.Here, we focus on two declining species: Boloria selene (Dennis & Schiffermüller) and Boloria euphrosyne L., Lepidoptera: Nymphalidae. We hypothesise that these species differ in their preferred breeding habitat, and this is driven by differences in their temperature preferences, mediated by vegetation cover.We use mark‐release‐recapture techniques and oviposition observations to characterise and compare adult distribution, habitat use and oviposition site preferences of the two species.Egg‐laying females of both species are shown to occur in areas with relatively high abundance of the larval food plants, Viola spp. (violets), principally V. riviniana, and they oviposit where Viola spp. abundance is locally high. However, in contrast to B. selene, ovipositing B. euphrosyne tends to occur in areas with relatively short and sparse cover of vegetation.B. euphrosyne oviposit in sites with a relatively high plant surface temperature irrespective of ambient temperatures, in contrast with B. selene in which the temperature of oviposition sites increases as ambient temperature increases. These differential temperature strategies likely underlie differences in breeding habitat preference.Microclimatic cooling caused by increased vegetation growth in spring may be one reason B. euphrosyne is declining in the UK, while both B. euphrosyne and B. selene may be affected by declining Viola spp. availability. Our data provide further evidence that drivers of butterfly declines can be multi‐factorial, and paradoxically, that thermophilic species do not necessarily benefit from climate warming if responses of other species result in cooling of their habitats. [ABSTRACT FROM AUTHOR]

Private gardens are recognised as potentially important refugia for butterflies. Yet little is known about how gardens might be contributing to butterfly conservation, as their restricted accessibility has meant that garden habitats are not well‐represented in traditional monitoring schemes.Garden BirdWatch (GBW) is the UK's largest structured bird survey, comprising over 25 years of weekly bird counts from more than 14,000 gardens, predominantly occupying suburban and rural locations. Since 2007, a subset of GBW participants have additionally recorded the weekly abundances of butterflies. Using data for 14 seasons (2007–2020) from 7971 gardens with consistent butterfly monitoring, we present the first garden‐specific, national trends for 22 widespread butterfly species (37% of all UK butterflies).Half of the species investigated increased significantly in abundance in gardens between 2007 and 2020. Conversely, only one species, Wall (Lasiommata megera), showed a marginal reduction, though this change was not statistically significant.A strong, positive association between these new, habitat‐focused trends and those for UK butterflies more broadly, previously reported by the UK Butterfly Monitoring Scheme (UKBMS), indicates that patterns of abundance in gardens are largely a reflection of the changes that are occurring nationally. However, butterflies do appear to be faring better in gardens compared to the wider landscape. Averaging trends across non‐migratory species revealed that GBW recorded significantly greater increases over time than UKBMS.Effective monitoring of butterflies in gardens can produce reliable and informative population trends, and it provides important evidence of the significant role gardens play in sustaining butterfly populations. [ABSTRACT FROM AUTHOR]

Asynchrony in population abundance can buffer the effects of environmental change leading to greater community and ecosystem stability. Both environmental (abiotic) drivers and species functional (biotic) traits can influence population dynamics leading to asynchrony. However, empirical evidence linking dissimilarity in species traits to abundance asynchrony is limited, especially for understudied taxa such as insects. To fill this knowledge gap, we explored the relationship between pairwise species trait dissimilarity and asynchrony in interannual abundance change between pairs of species for 422 moth, butterfly, and bumblebee species in Great Britain. We also explored patterns differentiating traits that we assumed to capture 'sensitivity to environmental variables' (such as body mass), and traits that may reflect 'diversity in exposure' to environmental conditions and lead to niche partitioning (for example, habitat uses, and intra‐annual emergence periods). As expected, species trait dissimilarity calculated overall and for many individual traits representing response and exposure was positively correlated with asynchrony in all three insect groups. We found that 'exposure' traits, especially those relating to the phenology of species, had the strongest relationship with abundance asynchrony from all tested traits. Positive relationships were not simply due to shared evolutionary history leading to similar life‐history strategies: detected effects remained significant for most traits after accounting for phylogenetic relationships within models. Our results provide empirical support that dissimilarity in traits linked to species exposure and sensitivity to the environment could be important for temporal dissimilarity in insect abundance. Hence, we suggest that general trait diversity, but especially diversity in 'exposure' traits, could play a significant role in the resilience of insect communities to short‐term environmental perturbations through driving asynchrony between species abundances. [ABSTRACT FROM AUTHOR]

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 the 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. [ABSTRACT FROM AUTHOR]

Since the classic work of E.B. Ford, explanations for eyespot variation in the Meadow Brown butterfly have focused on the role of genetic polymorphism. The potential role of thermal plasticity in this classic example of natural selection has therefore been overlooked. Here, we use large daily field collections of butterflies from three sites, over multiple years, to examine whether field temperature is correlated with eyespot variation, using the same presence/absence scoring as Ford. We show that higher developmental temperature in the field leads to the disappearance of the spots visible while the butterfly is at rest, explaining the historical observation that hindwing spotting declines across the season. Strikingly, females developing at 11°C have a median of six spots and those developing at 15°C only have three. In contrast, the large forewing eyespot is always present and scales with forewing length. Furthermore, in contrast to the smaller spots, the size of the large forewing spot is best explained by calendar date (days since 1st March) rather than the temperature at pupation. As this large forewing spot is involved in startling predators and/or sexual selection, its constant presence is therefore likely required for defence, whereas the disappearance of the smaller spots over the season may help with female crypsis. We model annual total spot variation with phenological data from the UK and derive predictions as to how spot patterns will continue to change, predicting that female spotting will decrease year on year as our climate warms. [ABSTRACT FROM AUTHOR]

Biodiversity conservation is fundamentally linked to human values, attitudes, and behaviours. Nature connectedness, the strength of a person's relationship with nature, is an important determinant of pro-nature actions, and therefore vital for counteracting biodiversity loss. Citizen science may improve nature connectedness, though such outcomes are underexplored in comparison to scientific and educational results. Addressing this gap, we studied the experiences of participants in the Big Butterfly Count, a UK mass-participation citizen science activity that aims to raise awareness and gather data on the abundance of widespread butterfly and moth species. Participants completed surveys before and after the three-week Big Butterfly Count period (n = 382), and at six- to seven-week follow up (n = 345). Improvements in nature connectedness, decreased anxiety, and increased tendency to notice nature and butterflies, were found immediately after the count period, with improved wellbeing and nature noticing at follow-up. Stronger emotional responses during the butterfly count were associated with greater increases in nature connectedness and nature noticing. Qualitative data revealed mixed emotions, from sadness and concern about biodiversity loss, to feelings of hope and optimism through taking actions to help butterflies. These findings suggest that citizen science participation prompts people to notice and enjoy nature in ways that enhance their wellbeing and connection with nature, supporting the mutual health of people and the rest of the natural world. The study highlights the potential for nature-based citizen science to benefit conservation beyond the focal species or habitat, by changing how people think, feel and act towards nature more broadly. • Citizen science research rarely considers nature connectedness, an important driver of pro-conservation behaviours. • A quasi-experimental design explored the impact of citizen science participation on nature connection and wellbeing. • Big Butterfly Count participation increased nature connectedness and nature and butterfly noticing, and decreased anxiety. • Stronger emotional experiences were associated with greater increases in nature connection and nature noticing. • By improving human-nature relationships, citizen science makes important contributions to biodiversity conservation. [ABSTRACT FROM AUTHOR]