Biology subjects

Memmott, J.

Publications and source records attributed to Memmott, J..

3 recordsLinked to original sources

bioRxiv2025

The impact of artificial linear features on the pollination of plant communities

Linear features, such as road verges, hedgerows can function as corridors for species dispersal. Previous studies showed that these features could enhance movement of pollinators such as bees, increasing pollination success of bee pollinated plants. However, it remains unclear if these effects extend to communities of plants pollinated by other pollinators. We conducted a field experiment where we measured the pollination of phytometer plant communities linked by linear features. We constructed six 30m artificial linear features in both urban and rural meadows in the Southwest UK, and placed plant communities on either end of these linear features, comparing these to phytometers without linking linear features. Plant communities were assembled with seven species known to attract different groups of insect pollinators including bees, flies, and moths. We tested self-incompatibility of plant species and used their seed set to measure pollination. We found that linear features significantly improved the pollination success of three bee pollinated species, whilst the seed production of fly and moth pollinated species were either unaffected or less affected. Overall, it is likely that linear features benefit the pollination of some plant species more than others. Our results suggest that linear features play an important role in maintaining pollination for some plant species, highlighting the importance of evaluating community-level impacts of corridors on pollination. Given the importance of bees as pollinators, linear features can provide a practical strategy to conserve and improve pollination, but where species are fly or moth pollinated, alternative strategies may need to be considered.

ecology↗

bioRxiv2024

Decline of honeybees and its consequences for beekeepers and crop pollination in western Nepal

O_LIPollination service by insects is globally threatened, yet trends outside of Europe and North America are poorly understood. Therefore, in less-studied regions of the world, beekeeper records can provide valuable insights into changes in pollinator populations. C_LIO_LIWe conducted a questionnaire survey of 116 beekeepers in 10 villages in the Jumla District of western Nepal, where the native honeybee Apis cerana cerana is widely kept as a managed honeybee. We complemented the beekeeper survey with field data on insect-crop visitation, a household income survey, and an interview with a local lead beekeeper. C_LIO_LI76% of beekeepers reported declines in the Apis cerana cerana population. 86% experienced declines in honey yield per hive, and 78% reported declines in the number of beehives per beekeeper. Honey yield per hive fell by 50% between 2012 and 2022, whilst the number of occupied hives decreased by 44%. Beekeepers ranked climate change and declining flower abundance as the most-important drivers of the decline. C_LIO_LIThe drastic bee declines raise concerns for the future food and economic security of this region, where honey sales contribute to 16% of total household farming income. Apis cerana cerana plays a major role in crop pollination and contributes more than 50% of all flower visits to apple, cucumber, and pumpkin. C_LIO_LITo mitigate further declines in this region, we promote the use of pollinator-friendly farming practices including more wild flowers and maintenance of native habitat areas, and well-insulated log or top-bar log hives to buffer bees against extreme temperature fluctuations, which are expected to worsen with climate warming. C_LI

ecology↗

bioRxiv2021

Tripartite networks show that keystone species can multitask

Keystone species are disproportionately important for ecosystem functioning (1,2). However, while all species engage in multiple interaction types with other species, the importance of keystone species is often defined based on a single dimension of their Eltonian niche (3), that is, one type of interaction (e.g., keystone predator). Therefore, it remains unclear whether the importance of keystone species is unidimensional or if it extends across interaction types. We conducted a meta-analysis of tripartite interaction networks to examine whether species importance in one dimension of their niche is mirrored in other niche dimensions, and whether this is associated with interaction outcome, intimacy, or species richness. We show that keystone species importance is positively associated across multiple ecological niche dimensions, independently of species abundance, and find no evidence that multidimensionality of keystone species is influenced by the explanatory variables. We propose that the role of keystone species extends across multiple ecological niche dimensions, with important implications for ecosystem resilience and conservation. Significance StatementKeystone species are often identified by focusing on a single type of interaction (e.g., predation, pollination, herbivory) which contrasts with the multiple roles that species play in biological communities. We conducted a meta-analysis of 18 tripartite interaction networks to explore if keystonness is correlated across the multiple dimensions of species Eltonian niches. Our results suggest that species importance tends to span across multiple interaction types, independently from abundance, which can be key to understand community resilience and collapse in face of multiple threats.

ecology↗