Ecology

Pressures on connectivity in the

Dr Frank Schwartz is a Professor of Earth Science at Ohio State or feeding, seriously impacting animal Prairie potholes play a vital role in the life University, where his research focuses on hydrology, pollution and populations. cycles of these ducks, so the extent of their health. He is part of a research group that primarily studies the effects of presence directly affects the size of the Dr Franklin Schwartz and his colleagues are population each year. Their presence here is climate on in the Great Plains . currently studying how certain groups of dependent on weather conditions: in years animals move between patches of wetland when there is little rainfall, fewer pools are habitat in order to understand how this likely to form so the region can only support etlands are extremely therefore, support a diverse range of species is affected by human activities and how a smaller migratory bird population. These important ecosystems and contain many vital habitats. connectivity could be affected by future populations could therefore be vulnerable – they are defined as changes. to and other factors, such land areas that are Connectivity among these habitats is as changes in land use, that might affect the either permanently or essential, as it enables passage for various PRAIRIE POTHOLES sustainability of these wetlands. seasonally saturated with water, and cover animals. Wetland areas are vulnerable to The northern part of the Great Plains region Wapproximately 3% of the Earth’s surface. human activity, and are often located in of is sprinkled with “prairie Grasslands in the Great Plains area are Despite their small coverage, they store about areas where such activity is prominent potholes” – shallow indentations on the currently undergoing conversion into a third of the world’s carbon and have great (e.g. ports, farmland, industrial areas, ground surface that form pools and lakes farmland, which means that the extent of biodiversity, but their presence is dependent etc.). Human activities often lead to the when filled with water, mostly through grasslands surrounding prairie potholes is on climatic and weather conditions. destruction of wetlands and changing land snowmelt or rainfall. These potholes act Human activities can affect connectivity, reduced. It has been found that some species covers that can affect connectivity, adding as a brooding ground for many migratory prefer to settle in that are surrounded They support a wide range of species barriers to movement, and limiting network waterfowl, such as ducks, in the Spring and adding barriers to movement, and by a large area of grassland, and the and provide a wide range of services to connections among wetlands. Ultimately Summer months. These small water bodies grasslands act as pathways between wetlands our population. Thousands of resident animal habitats are destroyed, as well as promote the growth of freshwater plants that limiting networks between wetland for species to move along. The reduction bird species use wetlands as feeding and their ability to move between them. This act as a source of food, and enable ducks to of their extent limits the ability of animals to breeding grounds and many more use them could consequently reduce the numbers of safely rear their young before migrating south habitats – ultimately reducing animals’ move between these waterbodies and reach as a stop off during migration. Wetlands, ecologically favourable settings for breeding when the temperature drops. ability to move between them important habitat areas.

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RESEARCH OBJECTIVES The research team studies climatic and How specifically do humans impact shallow and constantly changing water anthropogenic forces affecting the wetland waterbodies of the Great Plains? depths. These features facilitate nutrient wetland systems of America’s Great The continuing conversion of grassland to cycling and a variety of aquatic plants Plains. At stake is the future of migratory corn and soybeans impacts both wetland and animals. Termed America’s “duck birds and other animals that depend waterbodies and surrounding habitat. factory”, the Prairie Pothole Region is the critically on the millions of water bodies Smaller waterbodies are simply ploughed most productive waterfowl habitat on the dotting the plains. and farmed during drier years, which , perhaps even the world. It also destroys their functional value as wetlands. supports shorebirds, grassland birds and FUNDING Land-cover conversions from grassland to other wildlife. This study was supported in the United farmland also negatively impacts nesting States by National Science Foundation success for ducks. Predicted increases Of waterfowl and amphibians, which do (NSF) awards 1340548, 1340648, in temperature and somewhat wetter you think is more vulnerable to changes and 1544083 (MacroSystems Biology conditions will promote the continuing loss in connectivity? Program). of grasslands to corn and soy crops. Amphibians are examples of animals that disperse over land. Unlike birds, they can't COLLABORATORS What strategies could be followed to fly to find new habitats. So, they will be Other members of our research collective protect these habitats if changes in land more sensitive to changes in connectivity, at State University, Kansas Top left: Prairie pothole wetlands and lakes are use and the climate have a detrimental particularly those stemming from land use State University, University of nodes (blue dots) on an interconnected ecological effect on them? changes. Even during the breeding season, Duluth, and the United States network (yellow lines) Top Right: Shown here are examples of migratory US government programs e.g., when most ducks are effectively tied Geological Survey. birds, including ducks with their distinctive Conservation Reserve Program (CRP), have down, waterfowl are able to interact green heads and black, American coots been in place since 1985 to pay farmers to with landscape at a larger scale than BIOS Bottom Right: After a long, cold winter in , ice on the ponds begins to melt anticipating retire land from farming. This program has do amphibians, meaning that they Team members have expertise the return of migratory waterfowl. helped to protect wildlife habitat. However, potentially have more options. in ecology, complex systems, the high commodity prices for corn and and hydrology. Franklin

© Krista Mountain-Prairie Lundgren/USFWS © soybeans, wetter weather and subsidised Is climate change or human land use Schwartz at Ohio State University LINKING HABITATS crop insurance have promoted a modern more likely to affect prairie pothole has interests in water, society Connectivity between different habitats expansion in farming. Thus, grasslands connectivity? and health. Ganming Liu is an and patches within the same habitat is a are actively being converted to corn and Land use conversion represents the assistant professor at Bowling critical factor affecting animal populations. soybean production and lands are being greatest impact to prairie pothole Green State University with Habitats are becoming more and more removed from the CRP. There are few connectivity. Smaller wetlands tend interests in modelling complex fragmented, as pressures, like urbanisation or grasslands in this region were developed and these potholes act as important nesting reasons to be optimistic for strategies to to disappear in the crop fields and hydrologic systems. Professor crop production and related environmental under a dry climate, on rocky, clayey soils, areas for many bird species, as well as small affect a turnaround. nests in larger wetlands are more Nancy McIntyre at Texas Tech changes, cause habitats to be destroyed. which are marginal for farmland. Now land mammals and amphibians. The extent of prone to predation with the loss of University works at the intersection Connectivity among these fragments or is increasingly being converted for corn the effect of climate change on these areas What makes the Prairie Pothole Region nearby grasslands. Climate change is of community ecology, landscape patches is essential for species to disperse. and soybean cultivation. This then leads to and the species that depend on them is an ideal area for migratory birds? expected to be a contributing factor ecology, and conservation. Chris So, for example, two different woodlands the destruction of pothole water bodies, currently unclear, as different species have The Prairie Pothole Region is unique in the no matter what climate ultimately Wright is a landscape ecologist could be connected by a stream with riparian leading to disconnections between remaining different levels of dependence on these world because its large size, nearly three emerges. Hotter and drier will reduce and complex system analyst (wetland) vegetation along its banks, or two potholes, ultimately reducing the availability wetlands, and the hydrological processes quarters of a million square kilometres, the wetland habitat as the numbers at the Natural Resources different patches of woodland within a field of these vital ecological refuges and the and behaviour of these lakes are also poorly incorporates several million wetlands ponds of pothole wetland decline from Research Institute, University of could be connected by a hedgerow. ability of species to move among them. understood. As such, it would be difficult to and lakes within grassland and agricultural evaporation. Hotter and wetter appears Minnesota Duluth. try and determine how they would respond to settings. These waterbodies are very to improve the prospects for farming but In the case of the Prairie Pothole Region, CLIMATE CHANGE climate change. productive for birds due to their relatively reducing waterfowl production. CONTACT waterbodies are connected by grasslands, Climate change is a source of pressure on Dr Franklin W Schwartz which facilitate the travel of amphibians many ecosystems and ecological processes. This is where the work of Dr Ganming Liu, Dr The Ohio State University and other animals among them and protect The presence of prairie pothole wetlands Nancy McIntyre, Dr Frank Schwartz and Dr 275 Mendenhall Lab nesting birds from predators. Native is affected by the weather and the climate, Christopher Wright comes in. Their current 125 South Oval Mall collaborative study aims to understand the use and climatic changes will affect this, varies for different groups of animals, Columbus OH, 43210 hydrological processes behind the prairie identifying barriers to connectivity and depending on how far they can travel. USA wetlands and how they respond to the establishing which habitats are less likely to If wetlands are still well-connected under Prairie pothole wetlands are affected current climate before modelling how they be affected by environmental change. Their the future climate for waterfowl, this may not E: [email protected] might respond to future changes in climate. research involves mapping potholes and then be the case for amphibians, so this research T: +1 614 292 6196 by the weather and the climate, and They then hope to use this knowledge to visualising a network by connecting pools is key for understanding how these different W: earthsciences.osu.edu/ further understand how waterfowl and that are within a certain proximity to one groups will be affected by climate change – act as important ecological refuges amphibians disperse and move between another, which displays how these wetlands identifying which areas would need a greater for many species wetlands, as well as determining how land are connected through time. Connectivity conservation effort.

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