Our research

Legacy Contaminants

 
 

Forest stakeholders in NB operated arguably the world’s largest aerial insecticide spray program during the mid 20th century. Organochlorine insecticides were used extensively to control spruce budworm populations. In aquatic ecosystems many invertebrates are sensitive to organochlorines.

We used sedimentary measures of DDT and remains of zooplankton and benthic invertebrates preserved within dated sediment cores from NB lakes to assess responses to and recovery from historic DDT use. Within our study lakes, invertebrate community composition and concentration suggest marked shifts in response to insecticide stressors and presumably other environmental changes in recent decades.

Overall, ecological recovery has not occurred at the most impacted lakes. This collaborative research with Karen Kidd highlights potential legacy effects of persistent pollutants.

 
 
Students sub-sampling a sediment core from Goodwin Lake, NB located in the headwaters of the Northwest Miramichi River. Rachel Carson highlighted this area in her seminal book Silent Spring.

Students sub-sampling a sediment core from Goodwin Lake, NB located in the headwaters of the Northwest Miramichi River. Rachel Carson highlighted this area in her seminal book Silent Spring.

Sediment core from Sinclair Lake, NB. We sample the upper 15 cm of sediments to better understand how lake ecosystems respond to organochlorine stressors used widely during the 1950s and 1960s.

Sediment core from Sinclair Lake, NB. We sample the upper 15 cm of sediments to better understand how lake ecosystems respond to organochlorine stressors used widely during the 1950s and 1960s.