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10 Things You May Not Know About Fish and Wildlife

Fish and wildlife play crucial roles across ecosystems and in human society. High animal diversity contributes to healthy ecosystems, and many species provide important economic benefits to our communities.

Fish and wildlife play crucial roles across ecosystems and in human society. High animal diversity contributes to healthy ecosystems, and many species provide important economic benefits to our communities. However, due to changing climate conditions, such as hotter temperatures and shifting precipitation patterns, many animals are losing habitat, facing tougher competition for survival, or experiencing other adverse impacts. Scientists are actively working to understand these impacts and help inform the important adaptation decisions that natural resource managers need to make. Learn more about our work with these 10 examples from the National and Regional Climate Adaptation Science Centers.

The 'i'iwi bird is a type of honeycreeper native to the forests of Hawai'i.

1. Hawaiian Forest Birds: Warming temperatures could expand the range of mosquitos in upper mountain forests, increasing the exposure of Hawaiian forest birds to avian malaria. Mosquito-carried diseases such as avian pox and avian malaria can devastate native Hawaiian forest birds. For decades, upper mountain forests have provided refuge for these birds because mosquitoes could not survive the cooler temperatures. However, scientists supported by the Pacific Islands CASC found that with warming temperatures, mosquitoes will move further upslope and increase in number. Unlike continental birds, island birds cannot move northward in response to these changes, but must adapt or move to less hospitable habitats to survive.

2. Waterfowl: The density of wetlands in the Prairie Pothole Region is expected to decline, impacting the waterfowl that heavily rely on this habitat. The Prairie Pothole Region spans parts of North and South Dakota, Minnesota, Montana, Iowa, and south-central Canada is known for its wetlands which provide critical habitat for breeding and migrating waterbirds. Scientists supported by the North Central CASC found that, on average, the density of wetlands is projected to decline across the U.S. Prairie Pothole Region. They also looked at 29 wetland-dependent bird species and found that all but two species are projected to lose habitat in the future.

3. Birds and Reptiles: As temperatures are expected to rise in the Southwest, birds and reptiles may experience a wide variety of impacts. Scientists supported by the Southwest CASC examined the current and future breeding ranges of 15 bird and 16 reptile species, and found that two-thirds of the species could experience a decrease in range, while one-third could see an increase. Scientists also found that the more fragmented the species’ habitats are under today’s conditions, the more vulnerable they appear to be in the future. These findings suggest that management actions focused on conserving and restoring connections between habitat patches could help lessen the severity of projected decreases in range.

4. Honey BeesUrban environments increase pathogen abundance in honey bees and reduce honey bee survival. Honey bees are important pollinators and play a significant role in food production and our economy. Researchers supported by the Southeast CASC found that honey bee colonies that are closer to urban areas and those managed by beekeepers are exposed to a higher abundance and more types of pathogens than those in rural areas. Studying urban areas gives scientists a unique glimpse into the projected future because many cities have already warmed as much, due to heat island effects, as they are expected to warm due to climate change by 2050 or even 2100.

Walleye Underwater
(Credit: Gretchen Hansen. USGS Photo Agreement Form)

5. Wisconsin Sport Fish: Warming lake and stream temperatures are changing habitat conditions, favoring some fish species while threatening others. In Wisconsin, scientists supported by the Northeast CASC found that populations of walleye, which rely on cold water habitats, are declining, while largemouth bass populations are increasing. Due to warming water temperatures, the percentage of Wisconsin’s lakes that support walleye is predicted to decline from 10% to less than 4%, while the percentage of lakes that will support largemouth bass is predicted to increase from 60% to 89%. These findings can help managers focus stocking efforts on lakes that have the best chance of supporting walleye into the future.

6. Cutthroat Trout: In Montana, native fish, such as westslope cutthroat trout, are losing habitat while invasive species, such as rainbow trout, are expanding their range. The westslope cutthroat trout has drawn generations of fly-fishers to the remote Flathead River system in western Montana. The mountain streams that cutthroat trout prefer were once too cold for rainbow trout. But warming water temperatures have allowed rainbow trout to expand into the cutthroat trout territory. Northwest CASC-supported scientists found that cutthroat and rainbow trout are now mating, decreasing the number of genetically pure westslope cutthroat trouts and spelling trouble for the long-term viability of this iconic species.

7. Pacific Lamprey and Pacific Eulachon: Pacific lamprey and Pacific eulachon are threatened by a variety of impacts to both their ocean and freshwater habitats. Pacific lamprey and Pacific eulachon are important traditional foods for Native American tribes of the Columbia River Basin and coastal areas of Oregon and Washington. Scientists supported by the Northwest and Alaska CASCs found that changing ocean conditions, such as higher than average sea surface temperatures, will adversely affect the life cycles of both lamprey and eulachon. Changes in the water flow and temperature of freshwater streams and rivers can also impact the spawning and survival of these species.

8. Species of Conservation Concern: Hotter and drier conditions in the South Central U.S. are shifting the habitats of important wildlife species. Scientists supported by the South Central CASC examined 20 species of conservation concern, including the black-tailed prairie dog and the lesser prairie-chicken, and found that some species are likely to gain habitat in the future, while others will lose. Findings from this project were incorporated into New Mexico’s Crucial Habitat Assessment Tool (CHAT). CHATs are being used by states across the western U.S. to facilitate conservation and project planning, and are useful to decision-makers at all levels of government.

Herd of a dozen pronghorn in a grassy steppe
Pronghorn - Credit: Tom Koerner, FWS

9. Pronghorn: In the arid Southwest, North America’s fastest land mammal is in decline – and drought may be partially to blame. While pronghorns remain numerous in some parts of their range, they are declining in parts of the Southwest. To uncover what the future might hold for southwestern pronghorn, researchers supported by NCASC looked at whether changes in temperature and precipitation were linked to population declines. They then used models projecting future climate conditions to estimate how the region’s pronghorns would fare in the future. These scientists found that 50% of the pronghorn populations they examined could disappear by 2090, as the arid Southwest becomes hotter and drier.

10. MooseProjected changes to winter and summer conditions in the North Woods may have profound implications for moose. In 2015, NCASC and the Northeast CASC partnered with the Wildlife Conservation Society to help New York state understand and plan for different scenarios of how moose might fare in the future. For example, when snow cover is reduced, winter ticks have higher survival rates, which can lead to higher rates of tick infestation on moose. Similarly, warmer winters can also impact the success of tree pests, like the wooly hemlock adelgid, which can be detrimental to the health of trees that represent an important winter food source for moose.

This year, 2018, marks the 10-year anniversary of the establishment of the National Climate Adaptation Science Center (NCASC). In those 10-years, the eight regional Climate Adaptation Science Centers (CASCs) were established, and together, NCASC and the CASCs funded over 425 science projects and built a network of research partners, resource management stakeholders, interdisciplinary staff, fellows, and early career researchers. 

In celebration of our work and accomplishments over the last 10 years, we have launched a monthly series featuring “10 Things You May Not Know” about different topics our science has focused on, including drought, glaciers, and wildfire.