What Should Conservationists Do Now?
Global climate change poses difficult challenges for conservation planners because of the scale and complexity of the problem, the long time required to learn about impacts, and the uncertainty associated with predictions about future conditions. In the long run, reducing greenhouse gas emissions seems prudent for reducing losses of waterfowl habitat, and DU is taking steps to assess and improve its own carbon “balance sheet.”
We must also consider strategies to help species and ecosystems cope with changes that are inevitable. The immediate challenge for DU is to judge what adaptations are reasonable now, even if we are unsure, and, second, what should be done to position ourselves to make even better decisions in the future. Several actions seem prudent:
1) Manage for resilience. Waterfowl habitats almost everywhere have been affected by human development, so any effects of climate change will be imposed on top of existing pressures. Reducing existing stresses on wetlands (e.g., nutrient loading, toxic chemicals, filling, drainage, soil erosion, urban encroachment) and associated uplands (e.g., overgrazing, intensive tillage) should reduce vulnerability to climate-induced changes and may be the single most achievable thing that we can do today to help prepare for a warmer but uncertain future. Increased variability and intensity of weather are expected too. Restoring or protecting complexes of wetlands of varying permanence and striving to restore habitats across a wide geographic area may help hedge against variable moisture conditions.
2) Encourage cross-jurisdictional planning where geographic shifts in ecosystems are likely. For instance, coordinated planning for the provision of wintering habitat in the Mississippi Valley and Gulf Coast regions seems prudent and is under way by conservation partners in these regions. Protecting habitat at the northern fringe of the pothole region where lengthening growing seasons will favor agricultural expansion into forested landscapes is another such action. DU will also support efforts by the national wildlife refuge system and by neighboring states and provinces to cope with species’ range shifts and changes to waterfowl habitat. We need to challenge conventional thinking about the most useful geographic areas, time scales, and partnerships for executing conservation plans.
3) Protect coastal wetlands from sea-level rise. Because it takes centuries for air and ocean temperatures to equilibrate, the atmospheric warming that has occurred already guarantees that sea level will rise for a long time. Everywhere wetlands are threatened by sea level rise, coastal zone regulations and development plans should be examined for opportunities to enable landward migration of wetlands (see sidebar). Restoration of the Mississippi River’s historic sedimentation processes may help restore wetlands on a large scale in southeastern Louisiana. In this way, efforts to restore rivers and floodplain habitats in the Midwest can benefit coastal wetlands by restoring historic river flooding and sedimentation downstream.
4) Seek opportunities to tie habitat conservation to carbon markets. The public may support added wetland restoration efforts where multiple benefits of nutrient reduction in water, flood abatement, groundwater recharge, carbon sequestration, and wildlife habitat can be realized simultaneously. At the state/provincial, federal, and international levels, DU’s science is already informing public policy discussions that seek to protect the ability of grasslands, wetlands, and other natural systems to absorb and store carbon, and that support market-based tools for conservation of environmental goods and services. Additional research is required to determine how different types of wetlands capture greenhouse gases and how wetland carbon stocks respond to drainage, flooding, nutrient inputs, or restoration. An obvious first step, however, is simply protecting intact wetlands and native grasslands to avoid additional release of stored carbon.
5) Employ adaptive management and increase research and monitoring work to improve management decisions. Earth’s climate is changing. Species and ecosystems will respond to these changes, and humans will continue to manage natural resources in the face of these changes. This presents difficult choices because we cannot know the full impacts of our management actions, resources are limited, and many stakeholders are involved. What we require, therefore, is a commitment to learning as we go and applying what we learn to improve future management decisions. We need to design monitoring programs that explicitly evaluate different climate-change predictions, sample over sufficient space and time, anticipate the possibility of unexpected changes, and are affordable and sustainable.
6) Be nimble; respond to new knowledge, threats, and opportunities. One specific challenge for waterfowl and wetland managers is that climate models were built to work at large geographic scales. Downscaling model predictions to smaller regions, such as subdivisions of the Prairie Pothole Region, would be highly desirable for conservation planning, but this is not well supported by current models. Emerging trends in agricultural land use will merit special attention.
Another immediate concern is the ability of agencies to detect shifts, should they occur, in a species’ population dynamics that could affect levels of sustainable harvest. Those responsible for managing hunted populations must be able to assess impacts and adjust harvest strategies in response to changing conditions.
7) Manage water wisely. Maintaining managed water is often an important part of maintaining wetland systems, and the needs are varied. In Louisiana, water-management plans that better resemble historical processes that rebuild Mississippi Delta wetlands are needed. In the Prairie Pothole Region, the likelihood of drier conditions should persuade stakeholders to develop less water-intensive agriculture, securement of long-term water rights and capacities, and holistic watershed plans. In California, the future will be all about the supply and management of transportable water.
None of these individual actions can offset altogether the expected effects of climate change on waterfowl, but they are concrete, low-risk steps that we can take now. They will be good for wetland conservation and inform future management choices whatever the extent of climate change. It’s time to act; delay will only make adapting more difficult in the future.