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Chronic wasting disease (CWD) is a widespread and incurable cervid disease. Despite continuing investments, the logistical challenges of CWD have required wildlife managers and researchers to navigate changing priorities with conflicting public perceptions. When overcoming difficult management problems, leveraging exploratory methods may identify previously unrecognized hypotheses. In this study, we interviewed wildlife managers and researchers to describe the diverse experiences of experts in the CWD management community. Our study asked about common management strategies used, challenges experienced, and attempted to understand how decision-making in CWD management is shaped and constrained. Our study participants experienced a wide range of constraining factors, primarily related to external influences. We also identified connections between these constraints and a common concern for staff and public burnout. The results of this study provide insight on constraints limiting CWD management success and possible explanations for some commonly recognized challenges resulting from social and ecological interactions.
Water-quality samples were collected quarterly during 1994-99 from 604 wells screened in the surficial aquifer system beneath the Charleston Naval Complex, North Charleston, South Carolina. Arsenic and thallium were selected for analysis because concentrations of these metals in some wells consistently exceeded the established (2001) drinking water maximum contaminant levels of 10 and 2 micrograms per liter, respectively. The analysis was conducted to determine the magnitude and spatial distribution of arsenic and thallium in ground water at the Charleston Naval Complex and to quantify arsenic and thallium concentrations in a dated sediment core from Shipyard Creek marsh near the southern boundary of the Naval Complex. The surficial aquifer system beneath the Charleston Naval Complex consists of an unconfined upper surficial aquifer and a confined lower surficial aquifer. Hydraulic connection between the two aquifers is limited or nonexistent throughout the system at the Naval Complex. The Charleston Naval Complex is divided into nine operational units designated as zones A through I. Arsenic and thallium concentration data were compiled and interpreted for the two surficial aquifers within each zone. Mean arsenic (n=603) and thallium (n=604) concentrations were calculated for water samples from each well screened in the upper and lower surficial aquifers. In the upper surficial aquifer, mean arsenic concentrations ranged from 0.9 to 339 micrograms per liter and exceeded 10 micrograms per liter in 29 percent of the wells. In the lower surficial aquifer, mean arsenic concentrations ranged from 1.0 to 97.4 micrograms per liter and exceeded 10 micrograms per liter in 23 percent of the wells. The greatest number of water samples with mean arsenic concentrations exceeding 10 micrograms per liter were collected from wells in the upper surficial aquifer at zone E in the northwestern part of the study area. Well clusters, defined as three or more wells in a solid-waste management unit or area of concern, where the mean arsenic concentration exceeded 10 micrograms per liter, were identified in association with 12 sites in the upper surficial aquifer-solid-waste management unit 039 (a drum-storage area) in zone A; solid-waste management units 044 (coal-storage area) and 047 (burning dump) in zone C; solid-waste management unit 065 (lead-storage area) and area of concern 556 (dry docks 3 and 4) in zone E; areas of concern 609 (building 1346 gas station) and 613 (locomotive shop) in zone F; solid-waste management units 006 (public works storage yard) and 008 (oil sludge pit), and area of concern 709 (fuel-delivery system wells 12, 13, and 14) in zone G; and solid-waste management units 009 (closed landfill) and 196 (south landfill) in zone H. One well cluster was identified in the lower surficial aquifer in association with solidwaste management unit 009 (closed landfill) in zone H. Mean thallium concentrations in water from all wells ranged from less than 1.6 to 32.6 micrograms per liter in water samples from the upper surficial aquifer, and from less than 1.6 to 67.7 micrograms per liter in water samples from the lower surficial aquifer. Mean thallium concentrations equal to or greater than 10 micrograms per liter were present in water samples from 21 of 604 wells (3.5 percent). Of the 21 wells, 14 wells were located at solid-waste management unit 009 (closed landfill) in zone H near Shipyard Creek, 8 wells in the upper aquifer, and 6 wells in the lower aquifer. One well cluster where thallium exceeded 10 micrograms per liter was identified in association with solid-waste management unit 009 (closed landfill) in the upper surficial aquifer. Mean arsenic and thallium concentrations in water were calculated for all wells screened in one aquifer and located in a single zone, and are referred to as zone mean concentration in this report. Zone mean arsenic concentrations in all nine zones ranged from 3.2 to 18 micrograms per liter in water samples from the upper surficial aquifer and from 2.7 to 22 micrograms per liter in water samples from the lower surficial aquifer. Zone mean thallium concentrations in all nine zones ranged from 3.2 to 13 micrograms per liter in water samples from the upper surficial aquifer and from 3.2 to 14 micrograms per liter in water samples from the lower surficial aquifer. Ground-water samples rarely had elevated (equal to or greater than 10 micrograms per liter) concentrations of both arsenic and thallium. Water samples had coincident elevated arsenic and thallium concentrations in 10 wells in zone H, 1 well in zone A, and 1 well in zone B. Sediment quality at Shipyard Creek marsh was investigated by collecting an 11.8-foot -long sediment core (SYC-1) adjacent to zone I. The mean arsenic concentration in sediment samples from SYC-1 (n= 160) was 3.05 milligrams per kilogram plus or minus 0.92. The mean arsenic concentration and standard deviation calculated for SYC-1 sediment samples fall within the standard error for the background mean arsenic concentration reported for South Carolina sediments (1.5 milligrams per kilogram plus or minus 2. 7). All but one sample (core depth =50 inches) was less than the threshold-effects level of 7.24 milligrams per kilogram. Acid extracts of the sediment samples were analyzed for thallium concentration, but none were detected. These data indicate no obvious change in arsenic or thallium concentrations with depth in the core.
Naval Support Activity (NSA) Memphis is a Department of the Navy facility located at the City of Millington, Tennessee, about 5 miles north of Memphis. Contaminants have been detected in surface-water, sediment, and ground-water samples collected at the facility. As part of the Installation Restoration Program, the Navy is considering remedial-action options to prevent or lessen the effect of ground-water contamination at the facility and to control the movement and discharge of contaminants. A numerical model of the ground-water-flow system in the area of NSA Memphis was constructed and calibrated so that quantifiable estimates could be made of ground-water-flow rates, direction, and time-of-travel. The sediments beneath NSA Memphis, to a depth of about 200 feet, form a shallow aquifer system. From youngest to oldest, the stratigraphic units that form the shallow aquifer system are alluvium, loess, fluvial deposits, and the Cockfield and Cook Mountain Formations. The shallow aquifer system is organized into five hydrogeologic units: (1) a confining unit composed of the relatively low permeability sediments of the upper alluvium and the loess; (2) the A1 aquifer comprising sand and gravel of the lower alluvium and the fluvial deposits, and sand lenses in the upper part of the preserved section of the Cockfield Formation; (3) a confining unit composed of clay and silt within the upper part of the Cockfield Formation; (4) the Cockfield aquifer comprising sand lenses within the lower part of the preserved section of the Cockfield Formation; and (5) a confining unit formed by low permeability sediments of the Cook Mountain Formation that composes the upper confining unit for the Memphis aquifer. Thicknesses of individual units vary considerably across the facility. Structural and depositional features that affect the occurrence of ground water in the shallow aquifer system include faulting, an erosional scarp, and 'windows' in the confining units. Underlying the shallow aquifer system is the Memphis aquifer, the primary source of water for NSA Memphis and the City of Memphis, Tennessee. Analyses of sediment cores, aquifer and well specific-capacity tests, and numerical modeling were used to estimate the hydraulic characteristics of units of the shallow aquifer system. The vertical hydraulic conductivity of core samples of the alluvium-loess confining unit ranged from about 8.5 x 10-5 to 1.6 x 10-2 feet per day, and the total porosity of the samples ranged from about 35 to 48 percent. The results of the aquifer test were used to estimate a horizontal hydraulic conductivity of about 5 feet per day for the alluvial-fluvial deposits aquifer. The total porosity of core samples of the alluvial-fluvial deposits aquifer ranged from about 22 to 39 percent. The vertical hydraulic conductivity of core samples of the Cockfield confining unit ranged from about 4.5 x 10-5 to 2.5 x 10-3 feet per day, and the total porosity ranged from about 41 to 55 percent. Well specific-capacity tests indicate that the horizontal hydraulic conductivity of sand units that compose the Cockfield aquifer range from about 0.5 to 3 feet per day. The vertical hydraulic conductivity of core samples of the Cook Mountain confining unit ranged from about 5.0 x 10-6 to 9.9 x 10-4 feet per day. Total porosity of core samples of the Cook Mountain confining unit ranged from about 30 to 42 percent. Ground-water flow and time-of-travel in the shallow aquifer system were simulated using the MODFLOW finite-difference model and the -particle-tracking program MODPATH. A three-layer, steady-state model of the shallow aquifer system was constructed and calibrated to the potentiometric surface of the A1 aquifer. Results of numerical modeling support the proposed conceptual hydrogeologic model of the shallow aquifer system. Ground-water time-of-travel in the A1 aquifer was simulated using an assumed effective porosity of 25 percent. Typical ground-water-flow velocities were on the order of 15 to 25 feet per year in the layer representing the Al aquifer in the model. The average residence time of particles seeded in this layer was about 800 years. Ground-water travel times were simulated at three sites within the Al aquifer: (1) the former N-6 hangar location, (2) the "grassy" area near Solid Waste Management Unit 7, and (3) at Solid Waste Management Unit 2. Results indicate close agreement between the particle-tracking simulations and the measured extent of contaminant plumes at the former N-6 hangar area and the grassy area near Solid Waste Management Unit 7. Based on the results of particle-tracking analyses of ground-water flow and the estimated locations of contaminant plumes at these two sites, the potential for contaminants to reach the Memphis aquifer in the next 100 years is negligible. However, particle-tracking analysis of ground-water flow at Solid Waste Management Unit 2 suggests that the time-of-travel of contaminants to Big Creek Drainage Canal could be less than 30 years.
This document describes the results of a 2.5-day rapid decision prototype workshop that evaluated management activities for chronic wasting disease (CWD) in Massachusetts (MA) that were either proactive (i.e., actions taken prior to CWD arrival/detection) or reactive (i.e., actions taken after CWD arrival/detection). The workshop was led by members of the Wildlife Section of the MA Division of Fisheries and Wildlife (hereafter referred to as MassWildlife) and included a group of agency communications specialists and district managers. U. S. Geological Survey staff and a volunteer acted as decision facilitators and led the analysis of the decision. Chronic wasting disease is an always fatal neurological disease that has spread across much of North America and threatens the health of deer populations in locations where it occurs (reviewed by Escobar et al. 2020). CWD can spread into new areas via two general mechanisms: (1) natural spread (e.g., dispersal of CWD-infected male white-tailed deer [Odocoileus virginianus]), and (2) anthropogenic spread (e.g., CWD spread facilitated by human intervention; Leiss et al. 2017, Escobar et al. 2020). Once CWD arrives in a state, natural resources agencies spend eight times more on CWD than agencies with no known cases; to cover these new CWD-related management activities, the natural resources agencies are typically forced to reallocate money from existing conservation priorities (Chiavacci, 2022). As of May 2024, there were 34 U.S. states and five Canadian provinces that had detected CWD positive free-ranging and/or captive animals in the family Cervidae (collectively referred to as ‘cervid’ hereafter), and the number of new states/provinces that are detecting CWD for the first time continues to grow (U. S. Geological Survey, May 2024). As of February 2024, the closest CWD positive state to MA with CWD detected in free-ranging white-tailed deer is Pennsylvania. To date, there have been no detections of CWD in MA, but testing has been limited in MA since 2012. The growing number of CWD positive states suggests that there may be increasing risk of CWD entering and establishing in MA as the number of CWD cases increases across North America. According to a 2023 survey of hunters in MA conducted by MassWildlife, 68% of hunters were concerned about CWD entering MA, and 88% of respondents said that it was at least moderately important to keep CWD out of MA; these survey results indicate that most hunters may support CWD risk reduction actions (Martin Feehan, Massachusetts Division of Fisheries and Wildlife, oral communication, 12 Feb 2024). In addition, 23.1% of responding deer hunters in MA have hunted for cervids in CWD-positive states/provinces in the last five years (not including states/provinces that have been able to successfully eradicate CWD following a positive detection). Participants of the survey were also asked, “how many deer have you harvested that tested positive for CWD?”. A total of three respondents said that they had one deer test positive for CWD, which, when extended to the whole population of MA deer hunters, results in an estimated 32 CWD positive deer harvested in CWD-positive states and imported into MA in the last five years. When asked about how they transport harvested deer from out of state into MA, the three participants indicated either “already processed & packaged” or “not applicable.” Note, that in MA, it is a violation of regulation to import whole carcasses or high-risk parts (e.g., head, brain, spinal tissues, bones) of any member of the Cervidae family (wild or captive) from a state/province that has detected CWD; it is legal to bring in deboned meat, cleaned skull caps, hides without the head, or a fixed taxidermy mount (Massachusetts Division of Fisheries and Wildlife, 2024a). To date, testing for CWD has been limited in MA since 2012. However, the data collected from the 2023 MA hunter survey suggests that there is a real risk of CWD being imported by a MA resident who has hunted in a CWD positive state. Therefore, given the higher costs of CWD management post arrival, the potential natural spread of CWD from nearby states, and the risk of CWD introduction via humanmediated cervid movement, MassWildlife is motivated to take actions that minimize the risk of CWD introduction and spread in MA with the ultimate goal of managing thriving wildlife populations and maximizing hunter and general public satisfaction, which are both parts of the MassWildlife mission. A 2.5-day rapid prototyping structured decision making workshop was held with MassWildlife staff to develop a decision framework for CWD management in MA. During the workshop, we defined the context and extent of CWD management activities in MA. Next, we identified four fundamental objectives that help achieve the mission of MassWildlife and that address stakeholder concerns. The fundamental objectives included: (1) maximizing hunter satisfaction and participation, (2) maximizing public satisfaction (non-consumptive), (3) maximizing health and sustainability of cervids, and (4) maximizing the efficiency of CWD management. Then, we generated a list of five alternatives (i.e., strategies) that varied the intensity of proactive and reactive actions. The five strategies were: (1) minimal proactive and minimal reactive actions, (2) intermediate proactive and intermediate reactive actions, (3) intensive proactive and intermediate reactive actions, (4) minimal proactive and intensive reactive actions, and (5) intensive proactive and intensive reactive actions. Lastly, we estimated the performance of each strategy on the fundamental objectives and assessed the overall performance of strategies relative to one another. We did so by first estimating the consequences of each alternative strategy on fundamental objectives using expert elicitation, and then, we elicited objective weights from MassWildlife staff to incorporate the relative importance of different fundamental objectives. Given that it is unknown when CWD will arrive in MA, we evaluated the performance of alternative strategies against fundamental objectives given three distinct scenarios for time to arrival of CWD: introduction in 2.5, 7.5, or 10+ years. The preliminary results of the rapid prototype indicate that the performance of the CWD management strategies that we evaluated depends on when CWD first arrives in MA. If CWD were to arrive in 2.5 or 7.5 years from now (February, 2024), then the ‘minimal proactive and minimal reactive’ strategy performs the best on both the deer population and cost fundamental objectives (fundamental objectives 3 & 4), but the ‘intensive proactive and intensive reactive’ strategy performs best on both of the human dimensions fundamental objectives (fundamental objectives 1 & 2) as well as the minimize CWD prevalence objective (also related to fundamental objective 3). We also found that public trust is likely to remain high across all five alternative strategies if CWD arrives after year 10, but public trust decreases if CWD arrives in year 2.5 or 7.5. After incorporating objective weights, we found that in scenarios where CWD arrives in the near-term (in years 2.5 or 7.5), an intermediate strategy (e.g., ‘intermediate proactive and intermediate reactive’ or ‘intensive proactive and intermediate reactive’) performed best, and the ‘minimal proactive and intensive reactive’ strategy performed worst. Conversely, if CWD were to arrive after 10 years, then the ‘minimal proactive and minimal reactive’ and ‘minimal proactive and intensive reactive’ strategies performed best. Collectively, these results suggest that the decision on which alternative strategy to employ is sensitive to when CWD arrives in MA. Following the discussion of the preliminary results, we identified the following four next steps. First, we discussed how a more detailed communications plan is needed and would likely alter the performance estimates of the alternative strategies on fundamental objectives 1 & 2, which were hunter and public satisfaction, respectively. The development of the communication plan would likely be easier once the alternative actions have been identified along with the audience and message. Second, a surveillance plan could be a useful tool to inform CWD management. Surveillance for CWD was performed in MA annually from 2002 to 2012 (n = 4,356 wild white-tailed deer and moose [Alces alces] samples). Limited surveillance was conducted from 2013 to 2022; and in 2023, 242 wild samples were collected. It is not clear whether MA needs a robust or minimal surveillance plan (e.g., is a minimal surveillance plan enough to detect the pathogen at the threshold that would trigger action?), or what type of invasion event the surveillance plan should target (e.g., natural vs anthropogenic spread events). The use of decision trees and a formal risk assessment may help answer these questions. Third, some of the elicited estimates from experts during this rapid prototype could be replaced with empirical data. Lastly, given that the decision was sensitive to when CWD arrived in MA and a surveillance plan would rely on the mode of introduction, forecasting and predicting the CWD invasion front and/or the likelihood of different incursion events across MA would provide valuable insights.
In April 1986, the U.S. Geological Survey began the National Water Quality Assessment program to: (1) provide a nationally consistent description of the current status of water quality, (2) define water quality trends that have occurred over recent decades, and (3) relate past and present water quality conditions to relevant natural features, the history of land and water use, and land management and waste management practices. At present (1987), The National Water Quality Assessment program is in a pilot studies phase, in which assessment concepts and approaches are being tested and modified to prepare for possible full implementation of the program. Seven pilot projects (four surface water projects and three groundwater projects) have been started. The Yakima River basin in Washington is one of the pilot surface water project areas. The Yakima River basin drains in area of 6,155 sq mi and contains about 1,900 river mi of perennial streams. Major land use activities include growing and harvesting timber, dryland pasture grazing, intense farming and irrigated agriculture, and urbanization. Water quality issues that result from these land uses include potentially large concentrations of suspended sediment, bacteria, nutrients, pesticides, and trace elements that may affect water used for human consumption, fish propagation and passage, contact recreation, livestock watering, and irrigation. Data will be collected in a nine year cycle. The first three years of the cycle will be a period of concentrated data acquisition and interpretation. For the next six years, sample collection will be done at a much lower level of intensity to document the occurrence of any gross changes in water quality. This nine year cycle would then be repeated. Three types of sampling activities will be used for data acquisition: fixed location station sampling, synoptic sampling, and intensive reach studies. (Lantz-PTT)
Private landowners are key partners in chronic wasting disease (CWD) management, especially in landscapes where there is limited public ownership. In this study, we evaluated landowners' preferences for alternative hypothetical CWD management programs using a stated choice experiment. We were particularly interested in understanding preferences for the use of financial incentives to motivate white-tailed deer harvest and facilitate hunter access to private lands as potential CWD management tools. We used latent class analysis to characterize preference heterogeneity among landowners stemming from patterns of choice. We compared means and distributions of auxiliary variables related to landowners' perceived risks, trust, attitudes toward management, and sociodemographics across latent classes stemming from choice model results. The pooled model demonstrated that reducing deer population density, providing payments to landowners for CWD-positive deer taken from their property, the form of incentives for public access, and banning recreational deer feeding had a small positive effect on respondents' choice of CWD management program. However, providing financial payments to hunters for harvesting CWD-positive deer and the use of targeted culling had the opposite effect on choice. Latent class models revealed that a majority of respondents exhibited a pattern of preference where all forms of incentives exerted a negative effect on choice, but smaller subsets of landowners positively evaluate the use of some incentives. Post-hoc contrasts revealed relationships between patterns of preferences and trust, risk, and attitudes toward CWD management with small to medium effects. Results demonstrated limited support for the use of financial incentives as a tool to manage access and harvest in the southeast Minnesota CWD management zone
American agriculture has provided abundant high-energy foods for migratory and resident wildlife populations since the onset of modern wildlife management. Responding to anecdotal evidence that corn residues are declining in cropland, we remeasured waste corn post-harvest in the Central Platte River Valley (CPRV) of Nebraska during 1997 and 1998 to compare with 1978. Post-harvest waste corn averaged 2.6% and 1.8% of yield in 1997 and 1998, respectively. After accounting for a 20% increase in yield, waste corn in 1997 and 1998 was reduced 24% and 47% from 1978. We also evaluated use of soybeans by spring-staging sandhill cranes ( Crus canadensis ) and waterfowl during spring 1998 and 1999. Despite being widely available in the CPRV, soybeans did not occur in esophageal contents of sandhill cranes ( n= 174), northern pintails ( Anas acuta , n= 139), greater white-fronted geese ( Anser albifrons , n= 198), or lesser snow geese ( Chen caerulescens , n= 208) collected with food in their esophagi. Lack of soybean consumption by cranes and waterfowl in Nebraska in early spring builds upon previously published findings, suggesting that soybeans are poorly suited for meeting nutrient needs of wildlife requiring a high-energy diet. Given evidence that high-energy food and numerous populations of seed-eating species found on farmland are declining, and the enormous potential risk to game and nongame wildlife populations if high-energy foods were to become scarce, a comprehensive research effort to study the problem appears warranted. Provisions under the Conservation Security subtitle of The Farm Security and Rural Investment Act of 2002 offer a potential mechanism to encourage producers to manage cropland in ways that would replace part of the high-energy foods that have been lost to increasing efficiency of production agriculture.
The stratigraphic occurrences and interpreted biostratigraphy of invertebrate fossil taxa in the upper San Joaquin Formation and lower-most Tulare Formation encountered at the Chemical Waste Management Kettleman Hills waste disposal facility on the North Dome of the Kettleman Hills, Kings County, California are documented. Significant new findings include (1) a detailed biostratigraphy of the upper San Joaquin Formation; (2) the first fossil occurrence of Modiolus neglectus; (3) distinguishing Ostrea sequens from Myrakeena veatchii (Ostrea vespertina of authors) in the Central Valley of California; (4) differentiating two taxa previously attributed to Pteropurpura festivus; (5) finding a stratigraphic succession between Caesia coalingensis (lower in the section) and Catilon iniquus (higher in the section); and (6) recognizing Pliocene-age fossils from around Santa Barbara. In addition, the presence of the bivalves Anodonta and Gonidea in the San Joaquin Formation, both restricted to fresh water and common in the Tulare Formation, confirm periods of fresh water or very close fresh-water environments during deposition of the San Joaquin Formation.
In white-tailed deer ( Odocoileus virginianus ), closely related females form social groups, avoiding other social groups. Consequently, females infected with chronic wasting disease (CWD) are more likely to infect social group members. Culling has been used to reduce CWD transmission in high-risk areas; however, its effectiveness in removing related individuals has not been assessed. We analyzed 11 microsatellites and a mitochondrial DNA fragment to assess: (1) the genetic structure in white-tailed deer in Minnesota, USA and (2) the effectiveness of localized culling to remove related deer. For (1), we genotyped deer culled in 2019 and 2021 in three CWD management zones, and deer collected in between zones. For (2), we only included culled deer, defining “culled groups” as deer obtained in the same township-range-section and year. We compared mean relatedness among deer from the same culled group (intra-group relatedness) and among deer from different culled groups (inter-group relatedness). We did not find evidence of genetic structure, suggesting that an outbreak in any of the management zones could naturally spread to the others. Culling removed deer that were on average more related than expected by chance (intra-group relatedness > inter-group relatedness), and most highly-related deer were culled in the same bait site.
Wildlife disease transmission, at a local scale, can occur from interactions between infected and susceptible conspecifics or from a contaminated environment. Thus, the degree of spatial overlap and rate of contact among deer is likely to impact both direct and indirect transmission of infectious diseases such chronic wasting disease (CWD) or bovine tuberculosis. We identified a strong relationship between degree of spatial overlap (volume of intersection) and genetic relatedness for female white-tailed deer in Wisconsin’s area of highest CWD prevalence. We used volume of intersection as a surrogate for contact rates between deer and concluded that related deer are more likely to have contact, which may drive disease transmission dynamics. In addition, we found that age of deer influences overlap, with fawns exhibiting the highest degree of overlap with other deer. Our results further support the finding that female social groups have higher contact among related deer which can result in transmission of infectious diseases. We suggest that control of large social groups comprised of closely related deer may be an effective strategy in slowing the transmission of infectious pathogens, and CWD in particular.
Efforts to restore water quality in Chesapeake Bay and its tributaries often include extensive Best Management Practice (BMP) implementation on agricultural and developed lands. These BMPs include a variety of methods to reduce nutrient and sediment loads, such as cover crops, conservation tillage, urban filtering systems, and other practices. Estimates of BMP implementation throughout the Chesapeake Bay watershed were provided for each year from 1985 through 2014 by the Chesapeake Bay Program (CBP). This dataset of BMP implementation is a compilation of actions reported by New York, Maryland, Pennsylvania, Delaware, West Virginia, Virginia, and the District of Columbia, and includes a wide array of management activities. Management actions vary among the jurisdictions and generally reflect the typical land use in each region. The amount of implementation also varies according to different priorities, reporting practices, and special programs within each jurisdiction. For example, extensive cover crop implementation was reported in Maryland whereas Pennsylvania, in general, has lower levels of BMP implementation reported on cropland. Pennsylvania and Maryland have higher levels of infiltration BMPs on developed land compared to those in Virginia. Conservation tillage BMPs accounted for the majority of reported agricultural BMP implementation in 1985. By 2014, however, a more diverse collection of agricultural BMPs was reported and conservation tillage BMPs accounted for a smaller proportion of overall reported agricultural BMP implementation. After the year 2000, land-use change BMPs, such as land retirement, pasture fencing, and forest buffers, were more commonly reported across the Chesapeake Bay watershed. Expected changes in nutrient and sediment loads in the Chesapeake Bay watershed due to BMP implementation were estimated by use of specially designed annual scenarios of the CBP Partnership Phase 5.3.2 Watershed Model. Nitrogen loads to streams were estimated to be reduced by 11 percent from 1985 to 2014 due to the implementation of BMPs. Compared with 1985, phosphorus loads were estimated to be 19 percent lower and sediment loads were estimated to be 23 percent lower by 2014 due to the effects of BMPs. Reductions in total nitrogen from 1985 to 2014 due to BMPs varied spatially across the watershed and were estimated to be as high as 42 percent in areas of the Eastern Shore of the Chesapeake Bay. Reductions in phosphorus and sediment also varied spatially, with the largest reductions occurring in the Potomac watershed upstream of Washington, D.C. and the Eastern Shore of Maryland, according to the CBP model results. Additional model scenarios were developed to estimate the effect of individual BMP types. The largest estimated reductions in total nitrogen loads on agricultural lands in 2014 were attributed to land retirement, animal waste management systems, and conservation tillage. The largest estimated reductions in total phosphorus loads on agricultural lands were attributed to animal waste management systems, pasture fencing, and phytase feed additives in 2014. The largest estimated reduction in total sediment loads on agricultural lands was attributed to conservation tillage, pasture fencing, and conservation plans. Dry ponds, wet ponds, and constructed wetlands were reported extensively throughout the watershed. These BMPs accounted for about half of the reduction in nitrogen loads from developed land to streams, half of the phosphorus reduction, and about a third of the sediment reduction.