Krischik Lab at work in the field, greenhouse and lab
Bumblebee (Bombus Impatiens ) colony in study on effects of insecticides. Note queen bee (largest bee).
Potting plants for rearing butterflies and bees.
Cages set up in greenhouse for bumble bee and butterfly studies.
Researchers Ivan Munkres and Matt Lagus performing bioassays on effects of insecticides on butterflies.
Monarch (Danaus plexippus ) larvae exposed to sublethal doses of neonicotinoid-treated milkweed.
Post doc researcher, Rebeca Gutierrez-Moreno, applying insecticide to mallow leaves for sublethal bioassay.
Painted lady butterfly (Vanessa cardui ) on mallow host plant in rearing cage with eggs.
Researcher Matt Lagus feeding Vanessa cardui for bioassays on the effects of insecticides.
Researchers Nick Partington and Matt Lagus performing bioassays on the effects of insecticides on butterflies.
Potato fields adjacent to pollinator habitat in pesticide drift study.
Potato fields adjacent to pollinator habitat in pesticide drift study.
Bumble bee on purple prairie clover habitat adjacent to sprayed potato field.
Beetle bank construction at St. Croix Regional Park for study on benefits of beetle banks in creating habitat for overwintering insects.
Researchers installing bee huts at St. Croix Regional Park study site.
All photos on this page, Krischik Lab 2019-2020.
Mast student Temo Balaxashvilli performing experiments on the effects of sublethal insecticides on Bombus impatiens colony health.
Researcher Matt Lagus inspecting bumble bee colony in bioassay study tent.
Outside plot for butterfly and bee host and nectar plants.
Swamp milkweed (Asclepias incarnata ) in greenhouse study cages for monarch (Danaus plexippus ) bioassays on the effects of insecticides on butterflies.
Monarch (Danaus plexippus ) feeding imitation nectar from watermelon boats for bioassay on effects of insecticides.
Painted lady butterflies (Vanessa cardui ) feeding on treated syrup in melon boat.
This table shows the concentration required to kill 10 (LC10 ), 50 (LC50 ), and 90% (LC90 ) of painted lady larvae for four different insecticides. A high value indicates that larvae can tolerate higher levels of the insecticide, while a lower value means it is more toxic. While chlorantraniliprole has relatively low toxicity to bumble bees, this study shows it is more toxic to painted lady larvae.
In a study on habitat near potato fields in MN, we found that 100% of samples collected in nearby pollinator habitat were contaminated with at least 1 pesticide, and up to as many as 15 different pesticides. The bars are the number of native plants containing insecticide residue. For native plants growing near potato fields, only 1 plant contained 1 insecticide residue and 2 plants contained 15 insecticide residues. Numbers above the bars indicate the number of plants that had trace amounts of insecticides. Plant samples were collected from habitat adjacent to 3 potato fields (Hastings, Big Lake: n = 30), 1 soybean field (North Branch: n = 6) and 4 corn fields (Alexandria: n = 28). All samples were analyzed for insecticide residues by USDA AMS Gastonia, NC.
Integrated Pest Management (IPM) research looked at best habitat for nesting and overwintering beneficial insects called beetle banks. 36 bank sites were installed at 3 sites in Washington county. At a citizen science field day we sifted and counted 10% of each beetle bank and found a mean of 131 insects in beetle banks compared to 1 insect in the control plots. More insects were found in the banks opposed to controls (no bank offered).
Best habitat for nesting and overwintering wild native bees: 36 bee huts for native stem nesting bees were installed at 3 sites in Washington county. At a citizen science field day, 36 reed bee huts were inspected at 3 sites which contained 236 occupied reeds or 95% of the huts occupied by nesting bees. The 36 bee huts were inspected again in April, 2020 which contained XXXX overwintered insects from 2019.
Leafcutter bee nesting in reeds of bee huts.
Dr. Krischik identifying insect species at beetle bank site, October 2019.