Body size is an integral functional trait that underlies pollination-related ecological processes, yet it is often impractical to measure directly. Allometric scaling laws have been used to overcome this problem. However, most existing models rely upon small sample sizes, geographically restricted sampling and have limited applicability for non-bee taxa. Allometric models that consider biogeography, phylogenetic relatedness, and intraspecific variation are urgently required to ensure greater accuracy. We measured body size as dry weight and intertegular distance (ITD) of 391 bee species (4,035 specimens) and 103 hoverfly species (399 specimens) across four biogeographic regions: Australia, Europe, North America, and South America. We updated existing models within a Bayesian mixed-model framework to test the power of ITD to predict interspecific variation in pollinator dry weight in interaction with different co-variates: phylogeny or taxonomy, sexual dimorphism, and biogeographic region. In addition, we used ordinary least squares regression to assess intraspecific dry weight ~ ITD relationships for ten bees and five hoverfly species. Including co-variates led to more robust interspecific body size predictions for both bees and hoverflies relative to models with the ITD alone. In contrast, at the intraspecific level, our results demonstrate that the ITD is an inconsistent predictor of body size for bees and hoverflies. The use of allometric scaling laws to estimate body size is more suitable for interspecific comparative analyses than assessing intraspecific variation. Collectively, these models form the basis of the dynamic R package, "pollimetry," which provides a comprehensive resource for allometric pollination research worldwide.

The survey of insect flower visitors to crops dependent on their pollination is an essential component in determining their effectiveness as pollinators. In most cases, different survey techniques are required for different crops because of variation in planting design, floral density, spatial distribution of flowers or where additional factors such as the variation in plant vigour are being explored. Here we provide survey techniques that have been, or are currently being employed to survey flower visitors across different crops in New Zealand and Australia. Future studies may consider the use of similar designs that will allow for increased standardisation within and between locations and studies. This will provide opportunities for improved direct comparisons between studies, and the ability to combine data sets to address broader spatial-scale questions regarding insect pollination.

1. Grazing can have considerable ecological impacts when managed inappropriately, however livestock production is a significant contributor to global food security and the removal of land from production is not always a viable option. Grazing management practices that incorporate periods of planned rest (i.e. strategic‐rest grazing) may be an alternative to grazing exclusion or continuous grazing that could achieve ecological and animal production outcomes simultaneously.
2. We conducted a meta‐analysis of global literature to investigate how strategic‐rest grazing mediates ecological (i.e., plant richness and diversity), biophysical (plant biomass and ground cover) and production response variables (animal weight gain and animal production per hectare) compared to continuously grazed or ungrazed areas.
3. Overall, total ground cover and animal production per hectare were significantly greater under strategic‐rest grazing than continuous grazing management, but biomass, plant richness, plant diversity and animal weight gain did not differ between grazing treatments. Increasing the length of rest relative to graze time under strategic‐rest grazing was associated with an increase in plant biomass, ground cover, animal weight gain and animal production per hectare when compared to continuous grazing.
4. Synthesis and applications . Understanding both the ecological and animal production trade‐offs associated with different grazing management strategies is essential to make informed decisions about best‐management practices for the world's grazing lands. We show that incorporating periods of rest into grazing regimes improves ground cover and animal production per hectare and that these benefits are more pronounced with increases in the length of time land is rested for. This extended rest also improves biomass production and weight gain compared to continuous grazing systems. Based on these meta‐analyses, we recommend that future research considers the duration of rest compared to graze time in comparisons of grazing systems.

Body size is an integral functional trait that underlies pollination-related ecological processes. This dataset consists of direct measurements of body size, as dry weight, and the intertegular distance (ITD) of 391 bee species (4035 specimens) and 103 hoverfly species (399 specimens) across four biogeographic regions: Australia, Europe, North America and South America. We used Bayesian mixed-models to test the power of ITD to predict interspecific variation in pollinator dry weight in interaction with different co-variates: phylogeny or taxonomy, sexual dimorphism and biogeographic region. In addition, we used ordinary least squares regression to assess intraspecific dry weight ~ ITD relationships for ten bee and five hoverfly species. Including co-variates led to more robust interspecific body size predictions for both bees and hoverflies relative to models with ITD alone. In contrast, at the intraspecific level, our results demonstrate that ITD is an inconsistent predictor of body size for bees and hoverflies. Collectively, these models form the basis of the dynamic R package, 'pollimetry’, which provides a comprehensive resource for allometric pollination research worldwide.

Livestock grazing can facilitate the maintenance of biodiversity in landscapes or cause landscape degradation and biodiversity loss. With a global population expected to surpass 9 billion people by 2050, there will be increasing pressure on the world's grazing lands to produce protein while minimising impacts on landscapes. This thesis explores the potential for grazing that incorporates extended and planned rest (Strategic-rest grazing, hereafter SRG) to enable continuing livestock production while also maintaining biodiversity and biophysical functions. In Chapter 2, I conducted a global meta-analysis comparing impacts of SRG to continuously grazed or ungrazed areas. I found that total groundcover and animal production per hectare were significantly greater with SRG compared to continuous grazing, while biomass, plant richness, plant diversity and animal weight gain did not differ between grazing treatments. Where the length of rest, relative to graze time increased with SRG, there were significant increases in biomass and further increases in groundcover and animal production per hectare in comparison to continuous grazing. These findings highlight the importance of incorporating the length of rest relative to graze duration into analyses comparing grazing systems. I found that the main focus of research around SRG differed between major geographic regions and climate zones. North American, Australian and New Zealand research mostly focused on short-term animal productivity, as did research in temperate areas. In contrast, research from Europe predominantly focused on biodiversity conservation. Research in more arid areas has focused largely on general sustainability for continuing animal production. Where richness and diversity of flora and fauna were compared between SRG and continuously grazed areas, responses were mostly favourable in SDG areas, or there was no difference. There were few examples of negative outcomes in SRG areas. Where richness and diversity in SRG areas were compared to ungrazed areas there was often no difference between SRG and ungrazed. Despite the often-favourable responses for production and ecological outcomes with SRG, a very small number of studies have considered the potential to achieve animal production and biodiversity conservation simultaneously with SRG approaches. This suggests we have limited understanding of trade-offs and synergies between these two goals. Ground-layer biodiversity and landscape function outcomes were assessed in naturalised pastures on six properties managed with short-duration grazing (hereafter SDG, a form of SRG) and compared with outcomes on properties managed in ways more typical of the region (largely continuous and with unplanned rest; hereafter RP). With SDG management there was approximately 19% greater perennial herbaceous cover and a corresponding 14% lower cover of undesirable introduced annual plants. Significant improvement in attributes relating to landscape functioning were also seen with SDG management, with environmental factors less important in influencing these attributes. Pasture composition also differed between management approaches with increased cover of favourable forage species and reduced cover of species that increase under heavy grazing pressure with SDG management. There was minimal difference in the richness and Shannon-Wiener diversity in the ground-layer of pastures managed in contrasting ways. Insects are an important component of overall landscape biodiversity and are sensitive to changes in land-use and agricultural intensification. Insect richness and abundance were assessed on RP and SDG properties and found to be significantly higher on SDG sites. These increases were likely largely due to the greater cover of tall perennial plants and litter cover and increased structural heterogeneity of the pasture sward with SDG management. These increases suggest there is potential for altered grazing practices to improve the capacity of grazed landscapes to provide ecosystem services from insects such as natural pest control and pollination, as well as provide food resources for wildlife. This thesis has highlighted the potential to balance animal production, biophysical and biodiversity outcomes with grazing incorporating extended rest and that research to-date has largely been on animal production outcomes rather than biodiversity responses. Importantly, it highlights that minimal research has considered trade-offs and synergies between animal production and biodiversity conservation outcomes, and the potential to achieve both simultaneously. If we are to meet the growing demand for protein from the world's grazing lands, while also preventing landscape degradation and sustaining biodiversity, it is essential to fill this knowledge gap.