Recent concern for the adverse effects from neonicotinoid insecticides has centered on risk for insect pollinators in general and bees specifically. However, natural resource managers are also concerned about the risk of neonicotinoids to conservation efforts for the monarch butterfly (Danaus plexippus) and need additional data to help estimate risk for wild monarch butterflies exposed to those insecticides. In the present study, monarch butterfly larvae were exposed in the laboratory to clothianidin via contaminated milkweed plants from hatch until pupation, and the effects upon larval survival, larval growth, pupation success, and adult size were measured. Soils dosed with a granular insecticide product led to mean clothianidin concentrations of 10.8 – 2193 ng/g in milkweed leaves and 5.8 – 58.0 ng/g in larvae. Treatment of soils also led to clothianidin concentrations of 2.6 – 5.1 ng/g in adult butterflies indicating potential for transfer of systemic insecticides from the soil through plants and larvae to adult butterflies. Estimated LC50s for total mortality (combined mortality of larvae and pupae) and EC50 for larval growth were variable but higher than the majority of concentrations reported in the literature for clothianidin contamination of leaves.

A set of experiments was conducted to determine the dietary clothianidin exposures that cause prepupal mortality in the absence of other adverse effects. Monarch larvae were raised from hatch to pupae on clothianidin contaminated swamp milkweed plants. Larval growth, larval survival, and prepupal survival were monitored throughout the experiments in which the exposures ranged from 1.4 – 2,793.1 ng/g leaf. Exposures of 5.4 – 46.9 ng/g leaf resulted exclusively in prepupal mortality while higher exposures of 1,042.4 – 2,793.1 ng/g leaf resulted exclusively in larval mortality. An LC50 and LC10 of 37 and 6 ng/g, respectively, were estimated based on prepupal mortality.

A set of experiments was conducted to determine the dietary clothianidin exposures that cause prepupal mortality in the absence of other adverse effects. Monarch larvae were raised from hatch to pupae on clothianidin contaminated swamp milkweed plants. Larval growth, larval survival, and prepupal survival were monitored throughout the experiments in which the exposures ranged from 1.4 – 2,793.1 ng/g leaf. Exposures of 5.4 – 46.9 ng/g leaf resulted exclusively in prepupal mortality while higher exposures of 1,042.4 – 2,793.1 ng/g leaf resulted exclusively in larval mortality. An LC50 and LC10 of 37 and 6 ng/g, respectively, were estimated based on prepupal mortality.

This dataset shows the effects of three insecticides (diazinon, fipronil, imidacloprid) and two fungicides (chlorothalonil, propiconazole) on larval metamorphosis in the coral Acropora tenuis. These five pesticides have been detected in the Great Barrier Reef lagoon and/or catchments. Settlement assays were conducted in Nov-Dec 2016 and Nov 2017. The aim of this research is to add toxicity data for inclusion into water quality guidelines. In order to improve water quality guidelines and subsequent risk assessments for pesticides in tropical marine ecosystems, the current study investigated the effects of three insecticides (diazinon, fipronil, imidacloprid) and two fungicides (chlorothalonil and propiconazole) on larval settlement and metamorphosis of the common reef-building coral Acropora tenuis larvae following 48 h exposures. Concentration-response curves were plotted to estimate no effect concentration (NEC) and effect concentration (ECx) values that inhibited larval settlement by 10% and 50% (EC10 and EC50, respectively). NEC is the concentration below which the pesticides are not expected to cause a reduction in larval metamorphosis. Methods: Gravid colonies (25-40 cm diameter) of the coral Acropora tenuis (Dana, 1846) were collected from 4 – 8 m depth in November 2016 from Trunk Reef (18°18.2’ S, 146°52.2’ E) and in November 2017 from Falcon Island (18°46’ S, 146°32’ E), GBR under Great Barrier Reef Marine Park Authority Permit G12/35236.1. Colonies were transported to the National Sea Simulator at the Australian Institute of Marine Science (AIMS) in Townsville and maintained in 1700 l flow-through holding tanks until spawning. Temperatures were held at 26-27°C, which was equivalent to the water temperature at the collection site. Gametes were collected from 8 parental colonies on each occasion, fertilised and symbiont-free larvae were cultured at approximately 500 larvae L-1 in 500 L flow-through tanks (Negri and Heyward, 2001, Nordborg et al., 2018). Larvae were competent to settle after 5 d and we used 7-10-day old A. tenuis larvae, each 800-1000 µm in length for consistency in the pesticide exposure experiments. The five pesticides in this study were > 98% pure and purchased from Sigma-Aldrich (NSW, Australia). Stock solutions (5 mg l-1) of all pesticides were dissolved in dimethyl sulfoxide (DMSO, final concentration < 0.01% (v/v) in exposures) and prepared in milli-Q water. A. tenuis larvae were exposed to diazinon (2.62 – 638 µg l-1), fipronil (1.57 – 1144 µg l-1), imidacloprid (3.88 – 947 µg l-1), chlorothalonil (0.69 – 507 µg l-1) and propiconazole (8.42 – 2053 µg l-1). Pesticide analyses were done by The University of Queensland, Queensland Alliance for Environmental Health Sciences (QAEHS), Woolloongabba, Australia. Static exposures were conducted in 20 mL glass scintillation vials containing 12-14 larvae made up to 10 mL filtered seawater (0.5 µm) with 6-7 concentrations (per pesticide) and 6 replicate vials per concentration. All tests included solvent controls containing identical concentrations of DMSO carrier. Seawater and solvent carrier controls were run in 12-18 replicate vials. Copper (CuCl2) was used as a reference toxicant at 6 concentrations between 1.12 – 36 µg L-1 and 6 replicate vials per concentration. Glass vials were transferred in random positions within a refrigerated shaking incubator (TLM-530, Thermoline Scientific) at 70 RPM to maintain gentle water movement which prevents larvae from attaching and undergoing metamorphosis in the containers (Negri et al., 2016). Larvae were exposed under a light intensity of approximately 60 µmol photons m-2 s-1 (12:12 h L:D cycle) and at 26.7 ± 0.7 °C (range). Vials were re-randomised at 24 h. After 48 h exposure larvae and treatment water were transferred into 6-well polystyrene culture plates (Nunc, NY, USA) and returned to the incubator but without water movement. Metamorphosis was initiated by the addition of crustose coralline algae (CCA) extract

Wild bee and butterfly samples were collected from the margins of agricultural fields located on five Conservation Areas in Missouri. In 2016 and 2017, samples were collected and composited by genera for a total of 90 samples. Samples were extracted via pressurized liquid extraction and solid phase extraction cleanup. Samples were analyzed for 168 pesticides and degradates using both gas and liquid chromatography-tandem mass spectrometry. Overall, 16 pesticides were detected. Pesticides detected in greater than 2% of the composite samples included: metolachlor (24%), tebuconazole (22%), atrazine (18%), imidacloprid desnitro (13%), bifenthrin (9%), flumetralin (9%), p,p’-DDD (6%), tebupirimfos (4%), fludioxonil (4%), flutriafol (3%), cyproconazole (2%), and oxadiazon (2%). Concentrations for individual pesticides ranged from 2 to 174 ng/g. Results indicate that wild pollinators are exposed to a wide variety of pesticides.

Wild bee and butterfly samples were collected from the margins of agricultural fields located on five Conservation Areas in Missouri. In 2016 and 2017, samples were collected and composited by genera for a total of 90 samples. Samples were extracted via pressurized liquid extraction and solid phase extraction cleanup. Samples were analyzed for 168 pesticides and degradates using both gas and liquid chromatography-tandem mass spectrometry. Overall, 16 pesticides were detected. Pesticides detected in greater than 2% of the composite samples included: metolachlor (24%), tebuconazole (22%), atrazine (18%), imidacloprid desnitro (13%), bifenthrin (9%), flumetralin (9%), p,p’-DDD (6%), tebupirimfos (4%), fludioxonil (4%), flutriafol (3%), cyproconazole (2%), and oxadiazon (2%). Concentrations for individual pesticides ranged from 2 to 174 ng/g. Results indicate that wild pollinators are exposed to a wide variety of pesticides.

- Text description of regulatory methods for estimating nectar and pollen concentrations from soil applications and seed treatments; - Table S1: Parameter set for imidacloprid used for simulations to assess the relative risk of neonicotinoid pesticides to hummingbirds. - Table S2: Full sensitivity results for ruby-throated hummingbird exposure to imidacloprid simulation - Table S3: Data used for estimating the Mineau scaling factor for imidacloprid. This dataset is associated with the following publication: Etterson, M., E. Paulukonis, and S. Purucker. Using Pop-GUIDE to Assess the Applicability of MCnest for Relative Risk of Pesticides to Hummingbirds. Ecologies. MDPI, Basel, SWITZERLAND, 4(1): 171-194, (2023).

- Text description of regulatory methods for estimating nectar and pollen concentrations from soil applications and seed treatments; - Table S1: Parameter set for imidacloprid used for simulations to assess the relative risk of neonicotinoid pesticides to hummingbirds. - Table S2: Full sensitivity results for ruby-throated hummingbird exposure to imidacloprid simulation - Table S3: Data used for estimating the Mineau scaling factor for imidacloprid. This dataset is associated with the following publication: Etterson, M., E. Paulukonis, and S. Purucker. Using Pop-GUIDE to Assess the Applicability of MCnest for Relative Risk of Pesticides to Hummingbirds. Ecologies. MDPI, Basel, SWITZERLAND, 4(1): 171-194, (2023).