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High concentrations of Total Dissolved Solids (TDS) and salts in drinking water, often exacerbated by drought conditions, have been reported to have a detrimental impact on cattle health and performance. This research investigated water quality parameters including TDS and salts (sodium, calcium, magnesium, potassium, aluminium, zinc, iron, manganese, carbonate, bicarbonate, sulphate, nitrate and nitrite). The project summarised the range of TDS and salts in feedlot drinking water across Australia, thus determining potential impacts on cattle health and production. Additionally, feedlots using surface water sources for drinking water had the cyanobacteria species present identified and quantified. Such a study has not previously occurred in Australia.

The study was split into four parts with this report including over 100 historical water samples taken prior to 2018; 68 feedlot managers/owners completed the survey regarding water use delivered in paper and online format; 82 water samples from April to June 2019 from 58 feedlots were analysed for a suite of parameters. Where multiple water sources were used, the source water was analysed, this occurred for 24 samples. Additionally, water samples that included surface water were analysed for cyanobacteria (27 samples). Feedlots participating in the project were equivalent to over 50% of the licenced cattle feedlots.

Of the 68 feedlots completing the paper based and online survey, the majority (64%) source their cattle drinking water from groundwater. On a per-head basis, the use of groundwater as a drinking water source became even more important, covering two thirds of surveyed feedlot cattle. Surface water from dams and rivers were also a common source of water, and less common sources included reverse osmosis treated water from coal seam gas operations, tank roof water, and irrigation water.

The majority of feedlots (75%) were not aware of any issues with their drinking water quality. Of those that indicated that they had concerns about their water quality, seven feedlots identified cyanobacteria (Blue green algae) and Escherichia coli as an issue; four identified turbidity and scale (likely from calcium build up) clogging floats; and four feedlots reported that they now treat water for use in their boiler, but do not treat for cattle, while one feedlot identified high iron as an issue for boiler water.

Among trough water samples analysed for TDS, the majority (86 %) were considered satisfactory for cattle consumption and would not be expected to limit animal performance (≤ 3,000 mg/L). There were, however, cases of poor water quality identified. The highest TDS reported was 11,600 mg/L in groundwater. This water was shandied with surface water and was the maximum in the mixed trough water (5,400 mg/L), which would be expected to limit cattle performance (NASEM, 2016). Chloride was present in the highest concentration of all anions analysed. Nitrate concentrations were highest in the groundwater samples with only one trough sample exceeding the nitrate concentration threshold of 20 mg/L (NASEM, 2016). Sulphate ranged from undetected (<0.3 mg/L sulphur as sulphate) to 575 mg/L, with the highest values in groundwater samples, all samples were below the 1,000 mg/L guideline (ANZEC, 2000). Only 3% of trough samples exceeded the ANZEC (2000) limit of 5 mg aluminium/L. Manganese concentration was highest in surface water samples with 57% to 90% of trough water samples sourced from surface water exceeding the 0.05 mg/L upper-limit guideline (NASEM, 2016). The biological significance of high manganese waters remains to be elucidated, although water concentrations are well below the Maximum tolerable limit reported for dietary Manganese of 1000 mg/kg dry matter (NASEM, 2016). Two surface water samples were in excess of the trigger value for Microcystis aeruginosa (11,500 cells/mL) and were reanalysed and tested for toxins. Only one sample was below a pH 5.1 and one sample above pH of 9.

Several water treatment scenarios were investigated with distributors and installers in Australia with reverse osmosis being the most suitable treatment option. As there are no Australian references for the effect of water quality on the performance of the cattle, Patterson et al. (2004), a publication from the USA, was used for the analysis of benefit and cost of water treatment with reverse osmosis. Treatment with reverse osmosis lead to increased, and more cost-effective, cattle productivity. However, the water used in the article by Patterson et al. (2004) had high sulphate concentrations, so the same responses are unlikely with Australian water. Future research testing water quality in the range of variation experienced by Australian feedlots, in a controlled manner, would allow the industry to determine the most relevant animal production gains and thus the benefits of reverse osmosis.

In conclusion, water quality was determined to be of suitable quality for the majority of feedlots surveyed. Isolated cases of poor water quality were identified. This project is beneficial to the industry as it has yielded a comprehensive understanding of the current sources and quality of feedlot drinking water for a single point in time. Overall, this project will improve feedlot decision-making regarding the conditions when water quality parameters may impact animal health and production in beef cattle feedlots.

Global agricultural crop production has become increasingly pollinator-dependant. Eusocial bee taxa within the family Apidae (e.g., honey bees, bumble bees, stingless bees) are wellestablished, successful crop pollinators globally. In particular, the ubiquity and wellestablished management of the European honey bee (Apis mellifera Linnaeus, 1758) has resulted in an overreliance of this pollinator worldwide. As other non-bee insects are also effective pollinators, it has become increasingly important to better understand the capability and life history needs of non-bee pollinator taxa so they can provide alternative, or supplementary, pollination services to managed bees and be supported within the landscape. This will ensure that consistent and reliable pollination services continue to be supplied to agricultural systems. This thesis investigates the pollination effectiveness and reproductive needs of the second most important pollinator taxon behind bees, the flies (Diptera), in pollinator-dependant food crops.

First, I conducted a systematic literature review on the diets and habitat needs of 431 crop flower-visiting fly species found globally and collated the existing information into a database. I was able to document the diets and habitat needs of 242 crop-visiting fly species (24 families and 119 genera) inhabiting all eight global biogeographical regions. I found that these crop-visiting fly species live in 35 different natural habitats and belong to 10 different feeding guilds. The results of this review identified major gaps in our understanding of the life history needs of crop-pollinating flies. In particular, current floral management schemes are largely focused on the resource needs of bees. As flies require other non-floral habitats to complete their life cycles, the diverse life history needs of flies and other non-bee taxa are not currently supported by existing pollinator management practices.

Second, I investigated the identity and efficiency of floral visitors to carrot seed crops. To do this, I conducted floral field surveys and pollen deposition trials across two years (2020-21) within varying environmental conditions in the Riverina region of New South Wales (NSW). I conducted 268 floral visitation surveys and identified 53 different insects (26 families) as floral visitors of seed carrot in temperatures ranging from 10.5ºC to 39.5 ºC and in 19.7% to 94.7% relative humidity. Spatial and temporal complementarity was observed across all dominant taxonomic groups (ladybeetles, bees, flies). Wild taxa generally matched managed honey bees in terms of abundance and their capability to transfer pollen between carrot parent lines. Further, wild taxa, not managed European honey bees deployed for pollination services, are providing the bulk of pollination services to Australian hybrid seed carrot.

Third, I determined the oviposition and habitat needs of pollinating hoverflies (Syrphidae: Eristalini). I did this by deploying 14 portable pools filled with soil and decaying vegetation across four seed carrot sites in the Riverina (NSW) region of Australia. All pools successfully supported the immature stages (eggs and larvae) of hoverflies after 12 to 21 days, and two beneficial species of flies were reared from the pools: Eristalinus punctulatus and Eristalis tenax (Linnaeus, 1758). Both species were effective pollinators of seed carrot in Chapters Three and Four of this thesis, respectively. These results suggest that deploying portable habitat pools filled with decaying plant materials in agroecosystems may be a successful management intervention to rapidly facilitate hoverfly pollinator reproduction.

Fourth, I assessed the effectiveness of the Australasian endemic golden native dronefly Eristalinus punctulatus (Macquart, 1847), at transferring pollen to hybrid seed carrot flowers. While both honey bees and the native drone fly were capable of depositing pollen onto seed carrot floral stigmas, golden native drone flies on average deposited more pollen onto stigmas than European honeybees. I also observed the first recorded event of natural oviposition of this fly species on the Mid North Coast (NSW) region. When observing the oviposition of this fly, I found that they oviposited within discarded raspberry plant root balls at a commercial berry farm. This observation, coupled with their demonstrated pollination effectiveness in seed carrot, suggests that these endemic flies could be supported as potential pollinators by deploying non-floral habitat within agroecosystems.

Finally, I compared the pollination effectiveness and activity patterns of two managed fly pollinators and two managed bee species at commercial raspberry and blackberry farms in two major berry growing regions in Australia: Mid North Coast (NSW) and Northern Tasmania (TAS). All taxa were capable of effectively pollinating raspberry and blackberry after one visit to a flower; however, the quality, weight, and number of pollinated drupelets per fruit varied depending on the taxa tested. In small cages, E. tenax and wild taxa pollinated raspberry fruits that weighed significantly more and were of higher quality than fruits harvested from C. stygia cages; however, there were no significant differences in the quality, weight, and number of pollinated drupelets in blackberry across all taxa. Further, in a blackberry polytunnel in Tasmania, E. tenax flies were significantly more active than European honey bees, and the fruits harvested from the E. tenax polytunnel did not differ from fruits visited by honey bees. These results demonstrate that some fly species could be effective supplementary, or alternative, pollinators to managed bees in commercial raspberry and blackberry.

This thesis demonstrates the importance of understanding how wild taxa, like flies and non-Apis bees, contribute to pollination service delivery, and how best to support these taxa within agroecosystems. Some flies and other wild taxa can provide significant and effective pollination services to some crops. If supported with foraging and habitat needs, these taxa may be able to provide similar pollination services to the honey bees used within these systems. Identifying wild pollinator taxa and their life history needs, assessing their capability as pollinators in a variety of crop systems, developing rearing techniques to commercialize effective taxa, and methods to support effective wild and managed pollinator assemblages within agroecosystems, are all important next steps to improve pollination services and yields of pollinator-dependant cropping systems globally.

The dataset consists of six tabs (each referring to a data chapter of the thesis). Data related to this dataset was collected online from Scopus research database (Chapter 2), and in the field from Lake Powell, Victoria, Australia (Chapter 5), and from the East-North Coast of New South Wales, Australia (chapters 3, 4, 6, and 7). Each tab has a spreadsheet with data from each thesis research chapter, and the content of each tab is explained below:

Chapter 2: A review of honey bee (Apis mellifera L.) interactions with other pollinators. The dataset consists of information extracted from reviewed articles, such as the title of the article, the authors, the year of publication, the country in which the research was performed, the place of study (i.e., open fields, or enclosed areas like glasshouses, cages, etc.), whether the study aimed to test competition or not, whether the study found and/or discussed competition or not, the type of interaction (i.e., direct or indirect) between honey bees and other species, the main methods used to perform the research, the interacting species with honey bees, and the behaviour performed by honey bees during the interaction.

Chapter 3: Observation of birds foraging on raspberry orchards. The dataset consists of the number of instances insectivorous or nectarivorous birds were seen perched on cages containing brown blowflies, within a raspberry orchard block. The first column is the days since flies were released inside cages until birds were seen inside the same cages, column two is the number of observational hours on each day of data collection, the following four columns have the bird species name and the number of individuals of each species, and the last column is the total number of individuals.

Chapter 4: Effectiveness of brown honeyeater (Lichmera indistincta) in pollinating blueberry flowers compared to insect pollinators. The dataset consists of stigmas collected after a single visit by one pollinator species. The first column is the pollinator ID, the second column is the identification of the stigma sampled, and the last column is the number of conspecific (i.e., blueberry) pollen grains deposited.

Chapter 5: Pollen collection by honey bee hives in almond orchards. The data consists of pollen pellets removed from different hives placed in almond orchards for pollination. The first column is the almond flower abundance during the flowering season (measures were always taken from the same tree branch throughout the study period), column two is the day of data collection (11 days in total), column three is the apiary identification, column four is the hive identification, column five is the heterospecific pollen richness (number of species), column six is the abundance of heterospecific pollen, column seven is the weight of heterospecific pollen collected from each hive, column eight is the weight of almond pollen collected from each hive, column nine is the total weight.

Chapter 6: Impacts of protective nets on pollen flow in blueberry orchards. The dataset consists of analyses of pollen deposition on blueberry stigmas under different netting treatments. The first column is the blueberry plant variety stigma was sampled from, column two the orchard block identification, column three is the netting treatment (i.e., covered - block completely covered by nets, partially - block partially covered by nets with sides open, and open - no nets), column four is the week of data collection (seven weeks in total), column five is the abundance of blueberry flower within each block (measures were always taken from the same blueberry plant), column six is the conspecific pollen abundance, column seven is the heterospecific pollen abundance on the stigmas, column eight is the heterospecific pollen richness in the stigmas, column nine is the point of data collection within the orchards (i.e., edge or center), and the last column is the number of non-blueberry flowers present in the remnant vegetation surrounding the orchard blocks.

Chapter 7: Effects of multiple visits on pollen deposition in blueberry, blackberry, and raspberry flowers. The dataset consists of pollen deposition analyses after multiple visits by different insect taxa in blueberry, blackberry, and raspberry flowers. The first column is the sample identification, column two is the crop species (i.e., Rubus sp - raspberry, rabbiteye - blueberry, or blackberry), column three is the crop species variety, column four is the block identification, column five is the date of sample collection, column six is the row number within the block that the sample was collected from, column seven is the identification tag used for the sample during collection, column eight is the total number if visits received by the sample (i.e., stigma), column nine is the combination of species that visited the stigma (i.e., MX - mix of species, SB - stingless bees, HB - honey bees, CR - carpenter bees), column ten is the number of conspecific pollen counted on the stigma, column eleven is the number of heterospecific pollen counted on the stigma, column twelve is the richness of heterospecific pollen counted on the stigma, column thirteen is the total visit duration time in seconds, column fourteen to thirty four is the visit duration of each subsequent visit.

1. Cattle diet plays a crucial role in the quality of dung and the consequent reproductive capacity of dung beetles. We investigated how three pasture types (improved native, forage oat and inter-sown rye/clover) influence the dung quality, the number of broods and reproductive output measured as brood size (dry weight and ellipsoid volume), development time and F₁ progeny size (beetle length and pronotum width) of Onthophagus binodis, Euoniticellus africanus and Euoniticellus intermedius.
2. Nitrogen content was highest in rye/clover-derived dung compared with improved native and forage oat. Improved native-derived dung had the highest carbon, energy, organic matter, pH and insoluble non-starch polysaccharide content, whereas forage oat had the lowest contents. Forage oat had the highest moisture content, ash and soluble non-starch polysaccharide content compared with the other pastures.
3. Progeny length was influenced by pasture type, with female E. intermedius, and males and females of O. binodis being 11.4%, 11.2% and 7.3% longer, respectively, in rye/clover-derived dung than forage oat dung. The pronotum width of O. binodis F₁ progeny was 9.8% wider when produced from rye/clover dung than forage oat.
4. Rye/clover- and improved native-derived dung provided the best resource for dung beetle reproduction compared with forage oat dung. Based on this study, cattle diet is important for consideration when evaluating reproductive ability and progeny measurements. Cattle diet should be further investigated as only three pasture types were investigated out of a numerous number of species and combinations.