About This Project

Significant declines in North American songbird populations over the past 50 years highlight the need for research on new and varied threats to these species. Current known contributing factors include habitat loss, pesticide use, and climate change, however little is known about the effects of heavy metal toxicity. This project aims to screen blood lead levels in songbirds admitted to a wildlife hospital to determine the risk of lead exposure and correlate with cause of admission and outcomes.

Ask the Scientists

What is the context of this research?

Lead pollution is a widespread, global issue affecting both humans and wildlife. Environmental contamination, especially in urban settings, is persistent despite bans on the use of lead in paint, gasoline, and other products. Lead toxicity in raptors and waterfowl due to ingestion of fishing sinkers or lead shot is well known and has been extensively studied over the last 50 years. The risk of lead toxicity in songbird species is less understood. The little research that exists suggests that songbirds may be at risk for lead exposure through ingestion of contaminated soils. There is evidence that even subclinical levels of lead exposure can lead to changes in songbird behavior.

What is the significance of this project?

Since 2018, we have performed blood lead testing on a small subset of songbird patients, mostly due to neurological symptoms. Of songbird patients tested, 11% had lead levels high enough for chelation treatment and 45% had detectable levels of lead in their blood (unpublished data). This research project will allow for broad screening of our songbird patients in order to determine the prevalence of lead toxicity in these species and better understand the potential impacts on a population level.

What are the goals of the project?

The main goal of this research project is to perform a concentrated testing effort to better assess the prevalence of lead exposure in songbirds admitted for rehabilitation. This information will improve rehabilitation efforts by determining the importance of screening for lead toxicity in this population. Due to their small size, it is more difficult to obtain a blood sample from songbirds and only a small blood sample can be safely taken. Therefore, a better understanding of the likelihood of lead exposure will help direct diagnostic testing for both patient welfare and resource management. This information will also expand our knowledge of population level impacts of lead exposure on songbird species.