From their environment to their behavior

Lessons learned from Illinois’ river otters.

By Nelda A. Rivera,  Nohra Mateus-Pinilla [PDF]


A river otter brings lunch to the latrine site. Photograph adapted from Mateus-Pinilla laboratory©


River otters are at the top of the trophic food chain, with a varied diet that, for Illinois’ otters, usually includes multiple fish species, mollusks, crayfish, and amphibians—as found by Satterthwaite-Phillips and collaborators in their fatty acid analysis of otter’s adipose tissue conducted in 2014 (Satterthwaite-Phillips et al. 2014). Other reports also indicate that river otters may pray on reptiles (including snakes and turtles), insects and their larvae, and occasionally other mammals and birds.

The variation in the diet of river otters makes them excellent biomonitors—organisms that accumulate in their tissues environmental contaminants—, providing quantitative information about the environment’s quality in specific areas and over time. In Illinois, another study conducted by Carpenter et al. (2014) identified organochlorine pesticides such as dieldrin and DDE (a Continue reading “From their environment to their behavior”

Record levels of banned insecticide found in Illinois otters | By Eric Freedman


The study published in the journal “Ecotoxicology and Environmental Safety” found high concentrations of chemical compounds in the livers of 23 otters in central Illinois.

“Thus otters serve as biomonitors — organisms that contain information on the quantitative and qualitative aspects of the environment — of wildlife exposure,” according to a new study. They also serve as biomonitors for human health because the same toxic chemicals found in otters have also been found in people who eat contaminated fish.

Estimated use of dieldrin. Graphic: Samantha Carpenter, Illinois Natural History Survey, University of Illinois, Urbana-Champaign

“there are specific watersheds that are areas of concern — not only for otters — for any of the wildlife species that are living in those places, especially those at the top of the food chain.”


Read the whole story at Great Lakes Echo, here.

Illinois river otters still exposed to chemicals banned decades ago | By Diana Yates

from left – Samantha Carpenter, wildlife technical assistant; Kuldeep Singh, Clinical Assistant Professor, Veterinary Diagnostic Laboratory, Clinical Assistant Professor, Pathobiology ; Nohra Mateus-Pinilla, Wildlife Veterinary Epidemiologist INHS ; and Jan Novakofski, Associate Vice Chancellor for Research for Compliance, Professor of Animal Sciences, Professor of Nutritional Sciences. Photo by L. Brian Stauffer.


CHAMPAIGN, IL. – Researchers report that river otters in Central Illinois are being exposed to polychlorinated biphenyls (PCBs) and pesticides that were banned in the U.S. in the 1970s and ’80s.

Read the whole story by the University of Illinois News Bureau here.