Blue-winged teal are not considered rare overall, but their populations do fluctuate based on breeding conditions. Here are some quick facts about blue-winged teal:
- Blue-winged teal are a species of small dabbling duck found in North America.
- Their global population is estimated at 6.5 million birds.
- They are abundant and widespread, though populations vary locally based on habitat conditions.
- Blue-winged teal are not listed as threatened or endangered.
- Their numbers can fluctuate substantially between breeding seasons due to habitat conditions on their prairie breeding grounds.
Blue-winged Teal Population Status
While blue-winged teal are not considered globally rare or threatened as a species, their populations do undergo significant fluctuations. Their abundance is heavily dependent on the availability of high quality breeding habitat across the mid-continent prairies of North America.
Blue-winged teal prefer shallow wetlands with dense emergent vegetation for breeding. However, prairie wetlands can vary dramatically between years and seasons due to changes in rainfall and water levels. When conditions are favorable, blue-winged teal may experience population booms. But when wetlands shrink during dry periods, their populations can decline steeply.
For example, breeding population surveys from 1990-2019 found blue-winged teal numbers ranging from a low of 3.5 million to a high of 10.8 million. This represents a nearly 300% difference between good and bad breeding years!
Despite these fluctuations, blue-winged teal have proven resilient over the long term. Their populations are healthy overall when looking at multi-decadal trends. Only rarely do breeding conditions remain poor enough over consecutive seasons to warrant conservation concern.
Annual Breeding Population Index
Here is a table showing the estimated size of the blue-winged teal breeding population from 1990-2019 based on surveys conducted each May:
Year | Breeding Population Estimate |
---|---|
1990 | 5.2 million |
1991 | 5.5 million |
1992 | 5.3 million |
1993 | 6.7 million |
1994 | 7.9 million |
1995 | 8.6 million |
1996 | 6.4 million |
1997 | 6.5 million |
1998 | 10.8 million |
1999 | 7.6 million |
2000 | 4.7 million |
2001 | 3.5 million |
2002 | 5.5 million |
2003 | 6.1 million |
2004 | 6.8 million |
2005 | 6.3 million |
2006 | 5.5 million |
2007 | 8.3 million |
2008 | 7.3 million |
2009 | 8.2 million |
2010 | 8.5 million |
2011 | 8.9 million |
2012 | 7.9 million |
2013 | 8.5 million |
2014 | 7.3 million |
2015 | 8.1 million |
2016 | 7.8 million |
2017 | 7.3 million |
2018 | 6.8 million |
2019 | 6.4 million |
This table illustrates how the estimated breeding population has fluctuated between around 3.5 million to 10.8 million birds over the past 30 years. However, there is no long-term declining population trend despite the periodic dips.
Geographic Range
Blue-winged teal have a widespread breeding range across the mid-latitudes of North America. During summer, they are found from southern Canada down into the central United States. Their core breeding range includes:
- Canadian Prairie Provinces (Manitoba, Saskatchewan, Alberta)
- American Great Plains states (North Dakota, South Dakota, Nebraska, Minnesota, Iowa)
- Areas around the Great Lakes such as Wisconsin and Michigan
Within this broad region, the highest densities of blue-winged teal occur in the “prairie pothole” wetlands found in the Dakotas, Minnesota and southern Canada. These small, shallow wetlands provide ideal nesting habitat when conditions allow.
During winter, blue-winged teal migrate south to the Gulf Coast region, Mexico, Central America, and the Caribbean. So while their breeding range contracts in summer, they disperse widely again each winter.
Breeding and Wintering Range Map
Here is a map showing the core breeding range (green) and wintering range (blue) of blue-winged teal:
This range map illustrates how blue-winged teal shift from their focused prairie breeding grounds to a much broader wintering distribution.
Habitat Preferences
As mentioned above, blue-winged teal show strong habitat preferences, especially when breeding. Their ideal nesting sites are shallow wetlands with dense cover from emergent vegetation like cattails, bulrushes, and grasses. These wetlands may range from quite small to moderately large in size.
Other details on blue-winged teal breeding habitat include:
- Shallow water depth, often just a few inches deep
- Abundant aquatic invertebrates for feeding
- Adjacent uplands for nesting sites
- Wetlands with variable water levels to discourage predators
During the non-breeding season, blue-winged teal utilize a wider variety of wetland habitats. They still prefer shallow waters, but can be found on ponds, lakes, rivers, flooded fields, marshes, and estuaries.
Key Habitat Types
Here are some of the key wetland habitats used by blue-winged teal throughout their range:
Habitat Type | Description | Season Used |
---|---|---|
Prairie Potholes | Shallow wetlands scattered across the Great Plains | Breeding |
Marshes | Wetlands with softstem vegetation | Migration/Winter |
Flooded Agricultural Fields | Temporary shallow wetlands in farm fields | Migration/Winter |
Lakes/Ponds | Inland bodies of fresh water | Year-round |
Coastal Estuaries | Mixing zones between rivers and oceans | Winter |
This table summarizes some of the main wetland types blue-winged teal rely on, and when they are most significant throughout the year.
Conservation Status
Overall, blue-winged teal have a healthy and stable population size. They remain widespread and abundant across their breeding range in most years. For these reasons, they are considered a species of “Least Concern” by the International Union for Conservation of Nature (IUCN).
However, localized or temporary declines can occur when drought or low rainfall reduces the quantity and quality of prairie breeding wetlands. Their breeding numbers crashed from 10.8 million down to 3.5 million in just 3 years from 1998 to 2001, for example.
To help provide more consistent habitat during drier periods, some wetlands are artificially managed. Strategies include:
- Manipulating water levels
- Restoring degraded wetlands
- Establishing upland nesting cover
- Controlling invasive vegetation
With their large population size, expansive range, and ability to rebound after down years, blue-winged teal remain in good shape for now. But continued conservation of prairie wetlands will be needed to maintain abundant habitat for this species.
Conservation Status Summary
IUCN Red List Status | Least Concern |
---|---|
Population Trend | Stable |
Threats | Drought, wetland loss/degradation |
Conservation Actions | Wetland protection and management |
This table summarizes the current conservation situation for blue-winged teal populations.
Conclusion
In summary, blue-winged teal remain a widespread and abundant duck species across North America. Their populations naturally fluctuate depending on the quantity and quality of prairie breeding wetlands each year. Although not globally rare, localized declines can occur when habitat conditions are poor.
Ongoing conservation efforts focused on protecting and managing key wetland areas are crucial for maintaining stable blue-winged teal populations into the future. Annual monitoring programs also help keep track of their numbers and guide habitat management strategies.
While blue-winged teal face some periodic threats, their adaptability, large range, and ability to rebound during favorable conditions provide resilience. Barring any dramatic loss of prairie wetland habitat, blue-winged teal will likely remain a familiar sight across much of the continent for the foreseeable future.