Faculty from the School of Natural Resources (SNR) shared information at the Sportsmen's Forum: Climate Change and Nebraska Wildlife, hosted by the National Wildlife Federation Dec. 1 in Hardin Hall.

The event was to "help people in Nebraska understand what are the implications right here in our state," said Duane Hovorka, who conducts agricultural policy and outreach for the National Wildlife Federation.

Rick Schneider, Nebraska Game & Parks Commission, presented an overview of the ways that scientists measure climate change, and concluded that, without reduction in greenhouse gas emissions, current projections show we'll "reach a global temperature in the next 50 to 100 years that most species haven't seen before. The future we're going to get [depends on] what we do with greenhouse gas emissions. We have a very short time, a couple of decades, to turn things around before they really get out of hand."

Bob Oglesby, a professor of climate modeling in SNR and the Department of Geosciences, discussed what climate models show, particularly with regard to snowmelt in the Rockies and streamflow in the Platte.

He noted that the flow of water in the Platte depends on having snow in the Rockies that melts gradually, rather than on less-predictable rainfall. With the caveat that climate models so far are global in scale, not well-suited to answering questions about a specific place, Oglesby said that all models agree on warmer temperatures and less snow in the Rockies.

As for rainfall in Nebraska, he said, "It could get wetter here or it could get drier. … While the global model results are equivocal for precipitation, every scenario includes significant warming and reduced snowmelt. Some more extreme scenarios suggest potentially catastrophic effects on the Platte, such as, it doesn't exist anymore. How concerned should we be? I would be very concerned, and start planning now."

Andy Bishop, coordinator of the Rainwater Basin Joint Venture, described Nebraska's Rainwater Basin as a region south of the Platte where temporary playa wetlands form each year, providing vital habitat for migrating birds. More than half of the state's 31,000 acres of Rainwater Basin wetlands are on private property, and the Joint Venture would like to restore an additional 20,000 acres of wetlands over the next 20 years. Meanwhile, the Joint Venture is working with landowners in key catchment basins to fill irrigation re-use pits so that water will flow into wetlands better.

"We're trying to get water down to wetlands so we can build more resilience and have a better wetland function over the long term," Bishop said.

Craig Allen, unit leader of the Nebraska Cooperative Fish & Wildlife Research Unit, focused on resilience and tipping points. He noted that a relatively linear change, such as a gradual increase in temperatures, can lead to sudden, non-linear system changes.

"Most of our ecological systems can occur in multiple states," Allen said. "Lakes can be clear, or algae-dominated. That flip from a clear state to algae-dominated can be quite sudden, usually as a result of slow input of increasing nutrients, usually phosphorus." Likewise, overgrazing or drought can turn grasslands into shrub-covered land or dunes.

Humans rely on natural systems for food, recreation, and other vital services. "It's in humanity's best interest to maintain systems and enhance their resilience when they are in desirable states," Allen said. "Radiation forcing might be relatively linear, but systems may have a rapid threshold response."

T.J. Fontaine, assistant unit leader of the Nebraska Cooperative Fish & Wildlife Research Unit, described how differing rates of adaptation among species to warmer temperatures pose challenges for migratory birds.

"The world is warming," he said. "One of the major effects is changes in seasonality – earlier springs and later falls. Animals and plants have the ability to some extent to respond to these changes, but some are responding much more than others. … What does this mean for a migrating bird? This is going to disrupt the predictability of the timing and availability of food." Fontaine concluded that any management actions need to consider not just the needs of migratory birds in one location, but how climate change is affecting their entire annual cycle.

Hovorka cited ducks and trout as vulnerable species of particular interest to people who hunt and fish. Nebraska is on the southern edge of the area where trout thrive. "Most of the state's streams are too warm," he said. "Trout can survive into about 72 degrees average temperature. The average summer air temperature is around 71 or 72 degrees Fahrenheit. If you add a few more degrees, it's going to warm up that water, and we may lose the trout fishing that we have."

Regarding ducks, Hovorka told the audience that the best habitat for duck breeding – "the duck factory of North America" – is in eastern North and South Dakota, in the shallow wetlands known as prairie potholes. If the temperature increases by a degree or two, increased evaporation could eliminate many of these shallow wetlands. Ducks would normally move with the habitat into Minnesota and Iowa, but, Hovorka said, "Over 90 percent of the prairie potholes in those two states have been drained or filled. That's the challenges we face."

In response to questions raised by the audience of about 50, the panelists said that climate change necessitates revaluing the risks of nuclear energy and the costs of energy conservation, and that some countries nearing the limits of the land's carrying capacity for humans have addressed population control as a matter of policy.