Caroline R Van Hemert, Ph.D. (Former Employee)

On this page, learn about USGS work with the Alaska Landbird Monitoring Survey (ALMS), Beak Deformities in Landbirds, and Boreal Partners in Flight (BPIF).

Over the past 26 years, Alaskans have witnessed a startling increase of beak deformities among Black-capped Chickadees and other species of resident birds. This disease, called avian keratin disorder (AKD), is characterized by debilitating beak overgrowth and other abnormalities of keratinized tissues. Affected birds have difficulty feeding and preening and may suffer high rates of mortality. If...

Environmental health is defined by connections between the physical environment, ecological health, and human health. Current research within the U.S. Geological Survey (USGS) recognizes the importance of this integrated research philosophy, which includes study of disease and pollutants as they pertain to both wildlife and humans. Due to its key geographic location and significant wildlife...

Links, videos, and news articles related to beak deformity research.

Literature Cited in the Beak Deformity web pages

Beak deformities can be caused by a variety of factors, including contaminants, nutritional deficiencies, disease, parasites, blunt trauma, or genetic abnormalities. In 2016, we identified a novel picornavirus (Poecivirus) in Black-capped Chickadees with avian keratin disorder (AKD). Our results suggest that Poecivirus is the most likely factor responsible for beak deformities in Alaskan birds...

The most commonly observed physical abnormalities among Alaskan birds are overgrown or crossed beaks.

The rates of beak deformities documented in Black-capped Chickadees and American Crows in Alaska are the highest ever recorded within a wild bird population anywhere.

Birds with beak deformities often have difficulty foraging and preening and may not be able to keep themselves warm and well-fed during cold winter months. Although some birds with beak deformities breed successfully, they typically encounter more challenges than normal birds.

Large numbers of Black-capped Chickadees with abnormal beaks were reported in south-central Alaska in the late 1990s. More recently, similar beak deformities have appeared in other species throughout the state. At least 30 Alaskan bird species are affected and the geographic extent of the problem appears to be growing. In addition to Alaskan observations, we have received increasing numbers of...

At least 30 Alaskan bird species are affected by beak deformities and the geographic extent of the problem appears to be growing. In addition to Alaskan observations, we have received increasing numbers of reports from other parts of North America and Europe.

Elevated ocean temperatures are linked to the development of harmful algal blooms (HABs). Toxins from these blooms may pose health threats to marine organisms, including seabirds. Since 2015, the USGS has worked with a variety of stakeholders to develop testing methods and research projects to better understand the geographic extent, timing and impacts of algal toxins in Alaska marine ecosystems...