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The Nature Conservancy acquired the Emiquon Preserve along the Illinois River, Illinois, with the primary objective of restoring ecological floodplain processes and habitats that promote and sustain native species and communities. The Conservancy convened an Emiquon Science Advisory Council prior to restoration implementation that identified key ecological attributes (KEAs) for riverine and backwater targets, KEA indicators, and acceptable ranges for those indicators. We assessed the application of this methodology to evaluate status of conservation targets and to inform future science and management at Emiquon. The KEA framework provided an important function of directing a systematic monitoring program that provided fundamental data on changing environmental conditions that were incorporated into annual target evaluations. Data show that 46–55% of all indicators were within acceptable ranges prior to reconnection of the preserve with the Illinois River. Recent completion of a water control structure represents a critical intervention that provides potential to improve conservation status of those floodplain and riverine targets that depend on water management and river connectivity. Continued review and modification of the KEA model in conjunction with a strategic monitoring program will provide critical information to guide relevant management decisions and testable hypotheses to reduce potential threats and achieve future restoration goals.

In the United States, government-mandated growth in the production of crops dedicated to biofuel (agrofuels) is predicted to increase the demands on existing agricultural lands, potentially threatening the per- sistence of populations of grassland birds they support. We review recently published literature and datasets to (1) examine the ability of alternative agrofuel crops and their management regimes to provide habitat for grass- land birds, (2) determine how crop placement in agricultural landscapes and agrofuel-related land-use change will affect grassland birds, and (3) identify critical research and policy-development needs associated with agro- fuel production. We find that native perennial plants proposed as feedstock for agrofuel (switchgrass, Panicum virgatum, and mixed grass-forb prairie) have considerable potential to provide new habitat to a wide range of grassland birds, including rare and threatened species. However, industrialization of agrofuel production that maximizes biomass, homogenizes vegetation structure, and results in the cultivation of small fields within largely forested landscapes is likely to reduce species richness and/or abundance of grassland-dependent birds. Realiz- ing the potential benefits of agrofuel production for grassland birds' conservation will require the development of new policies that encourage agricultural practices specifically targeting the needs of grassland specialists. The broad array of grower-incentive programs in existence may deliver new agrofuel policies effectively but will re- quire coordination at a spatial scale broader than currently practiced, preferably within an adaptive-management framework.

Best management practices (BMPs) are widely promoted in agricultural watersheds as a means of improving water quality and ameliorating altered hydrology. We used a paired watershed approach to evaluate whether focused outreach could increase BMP implementation rates and whether BMPs could induce watershed-scale (4000 ha) changes in nutrients, suspended sediment concentrations, or hydrology in an agricultural watershed in central Illinois. Land use was >90% row crop agriculture with extensive subsurface tile drainage. Outreach successfully increased BMP implementation rates for grassed waterways, stream buffers, and strip-tillage within the treatment watershed, which are designed to reduce surface runoff and soil erosion. No significant changes in nitrate-nitrogen (NO-N), total phosphorus (TP), dissolved reactive phosphorus, total suspended sediment (TSS), or hydrology were observed after implementation of these BMPs over 7 yr of monitoring. Annual NO-N export (39-299 Mg) in the two watersheds was equally exported during baseflow and stormflow. Mean annual TP export was similar between the watersheds (3.8 Mg) and was greater for TSS in the treatment (1626 ± 497 Mg) than in the reference (940 ± 327 Mg) watershed. Export of TP and TSS was primarily due to stormflow (>85%). Results suggest that the BMPs established during this study were not adequate to override nutrient export from subsurface drainage tiles. Conservation planning in tile-drained agricultural watersheds will require a combination of surface-water BMPs and conservation practices that intercept and retain subsurface agricultural runoff. Our study emphasizes the need to measure conservation outcomes and not just implementation rates of conservation practices.

Increased awareness of the contributions of nonpoint source runoff to the degra- dation of water quality in the Mississippi River and Gulf of Mexico emphasizes the need to increase conservation practices that reduce nutrient export from agricultural lands. To achieve long-term conservation goals in agricultural landscapes, it is important to understand farmers' perspectives on what practices are effective, practical, and economically attainable. We con- ducted a series of surveys, interspersed with focused outreach, of farmers in two agricultural watersheds in central Illinois in an attempt to better understand how outreach influenced their views on and adoption of conservation practices. Programs differed between the two water- sheds in terms of the levels of intensity at which outreach efforts were conducted. Survey results suggest that more intensive outreach efforts, such as one-on-one landowner visits, localized workshops, and tours, can increase adoption of conservation practices associated with cost-share programs. Technical and financial assistance provided in a timely manner that did not interfere with planting and harvesting were major incentives among farmers in both watersheds to participate in cost-share conservation programs. Primary disincentives among farmers to enroll in cost-share programs were associated with multiple programmatic changes and complex application processes. Results indicate that there remains a need for outreach that increases awareness and implementation of conservation and best management practices specific to reducing agricultural runoff from tile-drained sources. Mitigation of nonpoint runoff will also require more effective management of nitrogen application rates and timing in order to conserve freshwater resources in Midwest agricultural landscapes and downstream waters. Integrated outreach teams comprised of stakeholders and local conservation agencies may lead to successful outreach efforts and reduce demands on limited conservation agency staff time.

Many wetland-dependent birds are thought to be experiencing significant population declines, although population trend data for this suite of birds are rare and the causes of declines poorly understood. We used a 26-year dataset (1980–2005) of wetland bird abundance and distribution among 196 wetlands in northeastern Illinois (i.e., Chicago and its suburbs) to evaluate population trends and identify underlying ecological causes. We used aerial photography and GIS to quantify wetland habitat structure (i.e., the extent of emergent vegetation) and changes in surrounding land use. We then evaluated how changes in land use affected the structure of wetlands and ultimately wetland bird populations. Of the 12 species analyzed, seven experienced significant declines, three showed non-significant declines, and two experienced significant increases. Population declines could not be attributed to wetland loss because none of our wetlands were destroyed. Concurrent research at these wetlands also suggests that neither low adult survival nor poor reproductive success were responsible for the declines. Increased development within 2 km of wetlands, however, was associated with extreme changes in the structure of wetlands. Wetlands tended either to lose much of their vegetation and become open ponds, or become rank stands of dense vegetation. Both changes made wetlands less suitable for many wetland birds. While “no net loss” legislation may protect wetlands from being filled or drained, development near wetlands appears to be altering hydrology, resulting in habitat degradation and population declines of several wetland-dependent bird species.

Wetlands are dynamic and can be destroyed and created quickly by natural forces. Therefore, birds inhabiting these wetlands may need to locate new suitable sites quickly. We investigated the cues wetland birds use when selecting a breeding site. Many species may use both habitat (e.g., vegetation structure) and social cues (presence of conspecifics and/or heterospecifics) when selecting a location for breeding. Using a two-species occupancy-modeling approach, we found certain wetland birds more likely to occur with other species, suggesting the presence of heterospecifics may influence settlement. Species that preferred wetlands with a roughly 50:50 ratio of open water to vegetation (hemi-marsh) occurred more frequently than expected with the Pied-billed Grebe (Podilymbus podiceps), suggesting these species may use the presence of grebes when selecting a habitat. Conversely, Yellow-headed Blackbirds (Xanthocephalus xanthocephalus) do not appear to use the presence of other species when selecting...

Grassland birds have declined more than other bird groups in North America in the past 35–40 years (Vickery and Herkert 2001, Sauer et al. 2008), prompting a wide variety of research aimed at understanding these declines, as well as conservation programs trying to reverse the declines (Askins et al. 2007). Area sensitivity, whereby the pattern of a species’ occurrence and density increases with patch area (Robbins et al. 1989), has been invoked as an important issue in grassland-bird conservation, and understanding the processes that drive area sensitivity in grassland birds is a major conservation need (Vickery and Herkert 2001). Here, we review the literature on North American grassland bird species that is relevant to the following questions. (1) What is the

The Henslow's sparrow (Ammodramus henslowii) is a species of high conservation concern due to long-term population declines and a small global population. Habitat loss is considered to be the most likely cause of Henslow's sparrow declines and the recent establishment of large acreages of undisturbed grasslands through the Conservation Reserve Program is considered to have the potential to benefit populations. I used data from Illinois' Spring Bird Count to estimate recent population trends and examine the association that changes in land-use, especially the establishment of Conservation Reserve Program lands, have had on local Henslow's sparrow population trends. My analysis shows that Henslow's sparrow populations have increased substantially within Illinois, USA over the last 10 years and that this population increase strongly coincides with the establishment of >400,000 ha of grasslands within the state by the Conservation Reserve Program. New rules allowing for managed haying and grazing on ...

Grasslandfragmentation and habitat loss are hypothesized to be contributing to widespread grass- land bird declines in North America due to the adverse effects offragmentation on breeding bird abundance and reproductive success. To assess the effects offragmentation on the reproductive success of grassland birds, we measured rates of nest predation and brood parasitism for four species of birds (Grasshopper Sparrow (Ammodramus savannarum, Henslow's Sparrow/Ammodramus henslowiij, Eastern Meadowlark (Stumella magna), and Dickcissel (Spiza Americana)) in 39 prairie fragments ranging from 24 to >40,000 ha in size in five states in the mid-continental United States. Throughout the region, nest-predation rates were significantly in- fluenced by habitatfragmentation. Nest predation was highest in small ( 1000 ha) prairie fragments. Rates of brood parasitism by Brown-headed Cowbirds (Molothrus ater), how- ever, were not consistently related to fragment size and instead were more strongly related to regional cowbird abundance, being significantly higher in regions with high cowbird abundance. Differences in nest-predation rates between large fragments (54-68% of all nests lost to predators) and small fragments (78-84% lost to predators) suggest that fragmentation of prairie habitats may be contributing to regional declines of grass- land birds. Maintaining grassland bird populations, therefore, may require protection and restoration of large prairie areas.

We tested Field Sparrows (Spizella pusilla), Vesper Sparrows (Pooecetes gramineus), Lark Sparrows (Chondestes grammacus), Grasshopper Sparrows (Ammodramus savannarum), Dickcissels (Spiza americana), Eastern Meadowlarks (Sturnella magna), and Western Meadowlarks (S. neglecta) to determine whether the low level (

Henslow's sparrow (Ammodramus henslowii) is one of North America's fastest declining songbirds. Population declines combined with a small global population have led to heightened conservation concern. I used data from the North American Breeding Bird Survey to assess the impact that the Conservation Reserve Program (CRP) has had on Henslow's sparrows throughout their United States breeding range. My analysis suggests local Henslow's sparrow population trends are correlated with CRP enrollment, with populations increasing more in areas with relatively high local CRP enrollment, and that CRP appears to be playing a significant role in reversing long-term population declines.

A computer model and data from the North American Breeding Bird Survey (BBS) were used to examine the effects of changes in the area and disturbance patterns in agriculturally associated grasslands on the demographics of bobolink Dolichonyx oryzivorus populations in a 37 000 km 2 area in northern Illinois. Input parameters for the computer model were based on documented declines in the area of hay, pasture, and oats and on changes in the timing and frequency of hay field cutting. Declines in the area of agriculturally associated grasslands strongly influenced the model population and resulted in an estimated overall bobolink population decline of 95% between 1952 and 1992. An increase of nearly two weeks in the median date of first cutting of alfalfa hay had a weaker impact on the model population. Field data for this area from the BBS suggest a bobolink population decline of over 90% between 1966 and 1992, a decline that was significantly correlated with documented declines in the regional area of pasture, alfalfa hay and oats. Although they cannot discount the possible effects of other factors, the model and empirical data I present demonstrate that declines in agricultural grassland habitat, and changes in the timing and frequency of hay field cutting, have the potential to produce significant regional population declines in grassland bird species inhabiting agricultural landscapes.

The influence of area and vegetation structure on breeding bird communities associated with 24 Illinois grassland fragments (0.5—600 ha) was studied between 1987 and 1989 to document the effects of habitat fragmentation in a severely fragmented midwestern landscape. Fragment area strongly influenced bird communities within grasslands and accounted for a high percentage of the variation in mean breeding bird species richness among fragments (R2 = 0.84). Breeding bird species richness patterns within 4.5—ha subsections of these grasslands also significantly increased with fragment size. Eight of the 15 (53%) most common bird species had distributions among fragments that were significantly influenced by habitat area, whereas six species (40%) had distributions within fragments that were significantly influenced by vegetation structure only. The Dickcissel (Spiza americana) was the only species with a distribution within fragments that was not significantly associated with either habitat area or vegetation structure. Four groups of birds were identified by an analysis of habitat area and vegetation structure preferences of individual species: area—sensitive species (5 species), edge species (3), vegetation—restricted species (6), and the Dickcissel. Estimates of minimal area requirements for the five area—sensitive species ranged from 5 to 55 ha. Discriminant analyses of habitat suitability within fragments suggests that the absence of area—sensitive grassland bird species form some small fragments may result, in part, from limited habitat availability. All five area—sensitive species, however, also regularly avoided structurally suitable habitat on small grassland fragments. As a result of the considerable extent to which native and, more recently, agricultural grasslands have declined in the Midwest, habitat fragmentation is likely to have caused midwestern grassland bird declines, especially for area—sensitive species.

The role of agricultural landscapes in biodiversity conservation has been largely ignored despite their potential role in conserving declining species. Within agricultural landscapes, set-aside programs may offer the most promising conservation opportunities due to the large area involved in these programs. I explored the relationship between set-aside effect size—on the basis of data from field studies of birds in cropland and set-aside fields—and population changes following establishment of these fields. Species whose abundance was most strongly influenced by the establishment of set-aside lands also tended to show positive changes in population trends following broad-scale implementation of the set-aside program. This relationship was strongest for grassland obligate birds, a group of birds experiencing broad-scale population declines throughout North America. There is now increasing evidence that set-aside lands within the United States are providing population-level benefits to grassland birds. Nevertheless, there are also increasing concerns about the stability of these set-aside lands in the face of increased demand for crops and rising commodity prices. If set-aside area within the United States is allowed to decline, additional declines of birds and perhaps other taxa within agricultural landscapes seem likely.

One of the big questions in conservation biology is how to design effective conservation programs in highly fragmented landscapes where little natural habitat remains. To direct limited resources in these landscapes, a solid framework for conservation efforts is needed. Illinois provides a good case study because much of its natural landscape was cleared early. By 1900, more than 97% of the state’s prairies and roughly 75% of the state’s original forests had been lost (Graber and Graber 1963). Today, Illinois remains one of the most intensively disturbed landscapes in the eastern United States (O’Neill et al. 1988). Illinois also has an extensive history of early biological study and cataloging (e.g., Kennicott 1855; Ulffers 1855; Forbs 1876; Ridgway 1889, 1895; Needham and Hart 1901; Forbs and Richardson 1908; Garman 1917). Therefore, there is a large historical database on which to evaluate the effectiveness of modem conservation actions and programs. Yet despite the high degree of disturbance in the state, Illinois has lost surprisingly few species (see review by Post 1991). This may be due in part to the fact that Illinois has an extensive network of legally protected preserves. Primack (1993) has suggested that establishing legally designated protected areas is one of the most critical steps in protecting biological communities. Additionally, Illinois has a tradition of assertive conservation action by groups such as Friends of Our Native Landscapes, the Natural Land Institute, The Nature Conservancy, the Illinois Nature Preserves Commission, the Illinois Endangered Species Protection Board, and the Illinois Department of Natural Resources (formerly the Department of Conservation). It is therefore a good place to examine the effects of a well-organized, focused conservation effort. Because of its relatively long history of conservation programs (Schwartz 1994), Illinois may be able to provide a template for conservation in other highly fragmented landscapes.

We examined factors influencing fox squirrel population dynamics in one exploited and two unexploited central Illinois woodlots between 1984–1987. Each fall hunters removed 54–76% of the resident squirrel population on the exploited area during a 50–55 day season. Despite this high annual removal of squirrels during the hunting season, the exploited population was able to attain pre-harvest densities within two to three months following autumn harvests. The reconstituted exploited population was composed largely of immigrants and had a significantly younger age structure than either of the protected woodlots. Reproductive intensities among the three areas were not significantly different. Annual disappearance rates for marked squirrels were significantly higher in the exploited woodlot (79%) than in either of the unexploited areas (44% and 45%). Disappearance rates outside of the hunting season (December - August), however, were not significantly different among exploited and protected populations. Our results indicate that successful recruitment of immigrants allows exploited fox squirrel populations to recover rapidly from hunting induced mortality if an adequate source of recruits is available. Moreover, our results show that hunting mortality is additive in fox squirrels and can greatly increase annual mortality in exploited populations. The maintenance of stable squirrel populations on areas receiving heavy hunting pressure depends on recruitment from nearby refuges or other lightly hunted areas.

We studied habitat selection by northern harriers (Circus cyaneus) and short-eared owls (Asio flammeus) on 2 intensively managed grassland sanctuary complexes in southeastern Illinois to determine the influence of grassland management on nest placement. Northern barriers showed a tendency (P < 0.001) to locate their nests in fields not disturbed by recent management activities (within the last 12 months). Overall, northern harrier nest placement was not influenced by whether fields were dominated by native or nonnative grasses (P = 0.307), Short-eared owls were irruptive breeders on these grasslands, and habitat selection could only be assessed in 1 year (1990). In 1990, all short-eared owl nests were located in fields disturbed by grassland management activities within the last 12 months. Although northern harriers are believed to be area-sensitive in the Midwest, grassland area did not influence nest-site selection for northern harriers on our sanctuaries (P = 0.622). Northern harriers and short-eared owls have generally contrasting habitat preferences. To provide appropriate habitats for both species, a mix of both managed and idle grasslands must be provided.

Life-history traits associated with midwestern breeding bird population trends were assessed using data from the North American Breeding Bird Survey (BBS). Analyses of BBS population trends by bird-habitat association, nest location and migratory strategy groups showed that grassland bird species had exhibited more extensive population declines between 1966 and 1993 than other groups of midwestern breeding bird species. Analysis of species representation in the midwestern BBS data, however, revealed significant biases in species representation based on habitat associations. Wetland bird species are significantly underrepresented on midwestern BBS routes, whereas urban and shrubland/early successional bird species are overrepresented relative to other groups of bird species. Because of these differences in species representation, additional surveys and monitoring programs are needed in order to compile a comprehensive pattern of population trends of midwestern