The Role of Haemosporidian Parasites on the Reproductive Success of the American Dipper in the Black Hills — 80a — Aidan Green, Oxana Gorbatenko

The American Dipper, Cinclus mexicanus, is a species of aquatic songbird that forages for aquatic invertebrates in mountain streams. The American Dipper population located in the Black Hills is geographically isolated and genetically distinct from other Western populations. However, unlike populations in the West, surveys from 1988-2018 have found a steady decline in their population and basin-distribution. Their decline is suspectedly caused by stream degradation caused by dams, urban and agricultural run-off, and mining activities that reduce the abundance of aquatic invertebrates. However, the role of potential biological factors on the reproductive success of American Dippers has not been investigated. Haemosporidian parasites are a group of three genera commonly found in birds, particularly those that live in areas with high altitudes, high precipitation, and proximity to water. Studies have observed reduced immune function, abnormal morphology, reduced body mass and increased nestling mortality in infected closely related White-Throated Dippers, Cinclus cinclus. Considering that American Dippers occupy optimal habitat for Haemosporidian parasites and have high nestling mortality rates, we monitored nest sites during breeding season and collected blood samples from American Dippers to establish the role these parasites have on reproductive success. Nests were monitored from April to July. Dippers were caught in mist nests, banded, measured, and collected 200 µL of blood. DNA was extracted from the nucleated blood cells and ran through qPCR to detect the presence or absence of Haemosporidian parasites. Infection and relative parasite concentration in positive samples were correlated with reproductive success determined from nest monitoring. Collected data will shed light into the role Haemosporidian parasites may play on the reproductive success of the Black Hills American Dipper.

University of Sioux Falls
Dr. Jessica Graham