Midwest Fish & Wildlife Conference 2019

AUTHORS: Scott A. Bonar, U.S. Geological Survey Arizona Cooperative Fish and Wildlife Research Unit; Norman Mercado-Silva, Centro de Investigacion en Biodiversidad y Conservacion, Universidad Autonoma del Estado de Morelos; Kevin L. Pope, U.S. Geological Survey Nebraska Cooperative Fish and Wildlife Research Unit

ABSTRACT: Evaluation of harvest regulations clearly benefits from standard collection and presentation of data. Advantages include the ability to better evaluate regulations over space and time; the ability to share data more effectively with colleagues across political boundaries; the capacity to design large studies; and improved communication with anglers. The American Fisheries Society developed standard methods to sample freshwater fish populations to aid in data comparison and collection, publishing them in 2009 in the book Standard Methods for Sampling North American Freshwater Fishes. This project involved 284 scientists from 107 different organizations across Canada, Mexico and the United States. Because of interest generated from the first edition, the Association of Fish and Wildlife Agencies (AFWA) and AFS are supporting development of a second edition of the book to move AFS closer towards having development of standard sampling methods as an ongoing activity of the society. Goals for the second edition include querying fish management agencies across North America as to areas of improvement, but otherwise retaining methods as similar as possible to preserve standardization; adding additional requested chapters and expanding participants; revising data averages and developing a process for updating methods in the future. Standardization in industry, medicine and science has led to great advances. American Fisheries Society standard freshwater fish sampling methods are a powerful tool for addressing a wide variety of changing objectives. One of these is evaluating harvest management regulations, where improved assessments are possible with larger samples sizes, the ability to design before-after-treatment-control experiments and collaborate across political boundaries when managing the continent's fish populations.

AUTHORS: Michael Redmer, Michael J. Dreslik, Eric T. Hileman – U.S. Fish and Wildlife Service

ABSTRACT: One of the most consistently cited threats to the Eastern Massasauga rattlesnake (EMR), even on protected lands, is the loss of preferred habitat (sunny, gramminoid-dominated plant communities) to succession from woody plants and invasive species.  The EMR is a conservation or management reliant species, and preferred management techniques (e.g., prescribed fire, mowing, and brush removal) converts and maintains preferred habitat. Life history studies indicate EMR populations can be sensitive to even small amounts of additive mortality, and crucial habitat management actions such prescribed fires present risks. Risks are especially apparent when actions are implemented during periods where populations are most concentrated and vulnerable, such as spring egress, thus creating a paradox amongst habitat and population needs.  Development of recovery implementation strategies will require monitoring to: (1) ensure habitat goals and responses are being achieved, and (2) populations of the EMR respond positively, both in an adaptive management framework. A monitoring protocol initially developed for the U.S. Fish and Wildlife Service, and then modified/implemented by the Illinois Natural History Survey (1999-present) and others, is now or will soon to be used to monitor at least six EMR populations in four states. The protocol gathers data on relative abundance, individuals within monitored EMR populations, and a suite of habitat variables. We propose  that mplementing the protocol at additional select EMR sites where habitat management is planned could be done relatively inexpensively and would allow a direct comparative approach to monitoring range-wide EMR recovery.

AUTHORS: Brian Washburn, USDA Wildlife Services; Adam Phillips, USDA Wildlife Services; Siddhartha Majumdar, University of Illinois at Urbana-Champaign; David Mayer, University of Illinois at Urbana-Champaign; Ryan M. Swearingin, USDA Wildlife Services; Edwin Herricks, University of Illinois at Urbana-Champaign; Travis L. Guerrant, USDA Wildlife Services; Scott Beckerman, USDA Wildlife Services; Craig Pullins, USDA Wildlife Services

ABSTRACT: Avian radar technologies have the potential to serve an important role in the quantification of bird movements and determining patterns of bird use in areas where human–wildlife conflicts might occur (e.g., airports, wind energy facilities). However, capabilities and limitations of these technologies are relatively unknown and ground-truthing studies are needed to help wildlife managers understand the biological meaning of radar information. We evaluated the efficacy of 3 X-band marine radar sensors for tracking birds and flocks of birds observed on the airfield at Chicago’s O’Hare International Airport, USA, during March 2011−November 2012. Specific information regarding field observations of birds or flocks was used to determine how frequently the 3 radar sensors provided corresponding tracks of these avian targets. In addition, various factors were examined to determine if they had any influence on the frequency of correspondence between visual observations and radar tracks. Of the 972 sightings of individual birds (49%) or flocks of birds (51%) by observers on the airfield that had the potential to be observed by the radar, 141 (15%) were tracked by at least one radar sensor. All confirmed tracks of bird/flocks were ≤4.8 km from these radars. Among the 3 radar sensors, larger-bodied bird species, bird/flocks flying at higher altitudes, and bird/flocks closer to the radars increased the ability of those units to track avian targets. This study provides new information regarding the performance of radar systems for tracking birds on the airfield of one of the largest and busiest airports in the world.

AUTHORS: Christopher B. Rees, Theodore W. Lewis, Sandra Keppner, Joshua Newhard, Aaron P. Maloy, Meredith L. Bartron – U.S. Fish & Wildlife Service

ABSTRACT: Populations of Northern snakehead (Channa argus) have been introduced in the Lower Hudson, Bronx, and Rondout watersheds of New York, Lower Delaware watershed of Pennsylvania and New Jersey, and the Lower Susquehanna watershed of Pennsylvania and Maryland. Because these observations are in close proximity to Great Lakes tributaries, Northern snakehead constitute a species of high invasion concern for natural resource agencies of Great Lakes connected waters. Traditional gear capture of Northern snakehead at low densities in their established range can be difficult due to the shallow, vegetation-rich habitat they typically occupy. As a result, significant environmental DNA (eDNA) detection efforts by the U.S. Fish and Wildlife Service and partner agencies in portions of the Oswego River drainage and canal system of New York have been explored. In any eDNA detection effort, it is important to have confidence in the accuracy of the markers used, and particularly when the effort involves the detection of aquatic invasive species where management and/or response actions may be taken. Here we highlight results from validation and comparative performance testing of several eDNA markers designed to detect Northern snakehead DNA and detection results of the 2018 environmental sampling efforts.

AUTHORS: Richard F Lance, Environmental Laboratory, US Army Engineer Research & Development Center; Xin Guan, Bennett Aerospace; Emy M. Monroe, Katherine D. Bockrath, Erica L. Mize – Whitney Genetics Laboratory, Midwest Fisheries Center, U.S. Fish and Wildlife Service; Chris B. Rees, Northeast Fishery Center, U.S. Fish and Wildlife Service; Kelly L. Baerwaldt, Midwest Fisheries Center, U.S. Fish and Wildlife Service

ABSTRACT: The Black Carp, Mylopharyngodon piceus, is an invasive species within the Mississippi River drainage that appears to be undergoing population growth and range expansion. Black carp are molluscivores that potentially threaten significant components of North America's rich indigenous diversity of freshwater bivalves. In order to help determine the presence of black carp in various waters and habitats, and to help track its spread, we have developed a suite of environmental DNA (eDNA) markers for this species. The markers were developed using whole mitochondrial genomes from 29 black carp from three countries and target three different mitochondrial DNA genes. The markers were further tested for reliability with a total of 41 black carp DNA samples and for specificity against DNA from numerous co-occurring fish species and against samples of natural waters free of black carp. Further tests to detect black carp in natural waters proved challenging, but ultimately successful. We further report on studies of which water fractions contain the bulk of black carp eDNA (the answer appears to be largely habitat dependent) and on the efficiency of different sampling options.

AUTHORS: Kristen Black, Illinois Learn to Hunt; Daniel Stephens, Illinois Learn to Hunt; Craig Miller, Illinois Natural History Survey

ABSTRACT: Surveys are commonly used to drive the development of public programs and to determine efficacy of those programs. This presentation will discuss how the Illinois Learn to Hunt program has used a series of surveys given to program participants and the public to drive the creation of a successful hunter recruitment, retention, and reengagement (R3) program in Illinois. Topics to be covered include, but are not limited to, survey creation, survey implementation, statistical analyses, and how survey results affect program management and execution.

AUTHORS: Catherine A. Richter, Katy E. Klymus, Nathan Thompson, Jeffrey C. Jolley, Duane C. Chapman – U.S. Geological Survey; PRESENTER: Rick Lance

ABSTRACT: Creve Coeur Lake is a large natural floodplain lake intermittently connected to the Missouri River near St. Louis, Missouri. The lake has been invaded by Bighead Carp (Hypophthalmichthys nobilis) and Silver Carp (Hypophthalmichthys molitrix), collectively known as Bigheaded Carp. Both are native to Asia. The invasion has resulted in impairment of the native crappie (Pomoxis spp.) fishery, and hazards to recreational users. Fish can enter the lake from the Missouri River only during high water events. During the winter of 2017-2018, an intensive removal effort was conducted using the unified fishing method. A total of approximately 108,129 kg of Bigheaded Carp was removed from the lake in February 2018. Monitoring of Bigheaded Carp environmental DNA (eDNA) concentrations was conducted at intervals before and after the removal effort. Water was sampled at 53 locations equally spaced along transects covering the entire surface area of Creve Coeur Lake, a smaller upstream connected lake (Mallard Lake), and the channel between the two lakes. We measured eDNA concentrations with quantitative PCR using two marker sets specific to the genus Hypophthalmichthys, and thus able to detect and quantify DNA from both species with equal efficiency. Our results showed a decrease in eDNA concentration with decreasing water temperature over three sampling events before the removal effort, in October 2017, November 2017, and January 2018. After the removal effort, we observed an increase in eDNA in March 2018, possibly resulting from the presence of injured fish and carcasses, followed by a sharp decrease in eDNA in April 2018. Our results illustrate the utility of eDNA monitoring of management actions, the advantages of repeated sampling over time, and some challenges associated with this application of eDNA analysis.

AUTHORS: Adam Landon, Illinois Natural History Survey; Craig Miller, Illinois Natural History Survey; Jerry Vaske, Colorado State University; James Absher, Environmental Sociologist

ABSTRACT: Research on recruitment, retention, and re-engagement (R3) has become increasingly important for fish and wildlife management agencies that are seeking to bolster participation in hunting and fishing, and ensure fiscal sustainability through increased license sales. To date, however, much of the literature surrounding R3 has been ad hoc with respect to theory explaining patterns of recreation behavior. In this study, we drew on the human dimensions literature to understand the influence of psychological involvement and perceived constraints on hunters’ commitment to the activity as potential new explanatory frameworks for R3 research. We hypothesized that hunters’ psychological involvement in the activity positively influenced their prolonged engagement, operationalized from patterns of hunting license purchase, and that perceived constraints had a negative effect. Data for this study were drawn from a large-scale cohort-based survey of Illinois hunters (n=6,000). Hunters were randomly sampled in age cohorts at two-year intervals based on their date of hunting license purchase over the period 2006-2018. Results suggested that psychological involvement may play an important role in hunters’ commitment to the activity, but that hunters placed different levels of importance on different aspects of involvement. Findings further suggested that perceived constraints negatively influenced commitment, whereby more constrained hunters’ were less engaged over time. Results of this study have implications for mechanism for R3 activity. Although demographic changes underpin broad patterns of hunting license sales, additional factors like involvement and constraints may account for commitment to the activity.

AUTHORS: K. Kali Rush, Jacob N. Straub, Matt Palumbo – University of Wisconsin-Stevens Point

ABSTRACT: The Wood Duck (Aix sponsa) is a focal species in the Upper Mississippi River and Great Lakes Region Joint Venture’s (JV) waterfowl habitat conservation strategy. The JV estimates the regional breeding population is 145,000 less than their population objective. In Wisconsin, the wood duck is the second most abundant breeding duck, but their population is declining like other Great Lakes States populations. To better understand population vital rates that could be related to the observed declines in abundance, our objectives were to quantify hen survival and hen and brood habitat use during the breeding season. We captured female wood ducks using decoy and nest box traps from 7 April to 5 July 2017 and 22 April to 20 May 2018, prior to nest initiation, and fitted hens with VHF radio transmitters (ATS 3930, 7g). Hen survival was estimated and compared between breeding status and among predominant habitat type used including emergent wetlands, scrub-shrub, and forested wetlands. We also monitored individuals and nest sites to estimate breeding propensity, clutch size, and nest success. In 2017 and 2018, 43 female wood ducks were captured. We used a known-fate model in program R to model hen survival as a function of breeding status (i.e. attempted nest or did not attempt nest) and habitat types. This approach yielded heretofore unavailable hen and brood survival estimates for breeding wood ducks in the state of Wisconsin to improve our knowledge of how wood duck populations are changing. 

AUTHORS: Mark J. Fincel, South Dakota Department of Game, Fish and Parks

ABSTRACT: In an effort to improve size structure of Smallmouth Bass Micropterus dolomieu in Lake Sharpe, a large Missouri River impoundment, the South Dakota Department of Game, Fish and Parks instituted two protected slot limits: restricted (305-457 mm) beginning in 2003 and relaxed (355-457 mm) beginning in 2008. We examined the effects of these regulations on Smallmouth Bass harvest and population characteristics and compared creel and population trends of Lake Sharpe Smallmouth Bass to adjacent reservoirs where Smallmouth Bass harvest was not regulated. Prior to the slot limit, the majority of the Smallmouth Bass harvest on Lake Sharpe was from 250-400 mm (PP355 mm, and angler catch of trophy Smallmouth Bass was observed, suggesting an effective regulation. However, a before-after-control-impact (BACI) study design and analysis indicated the slot limit regulation was not likely contributing to the observed increases in Smallmouth Bass size structure. Indeed, similar changes in size structure were observed in abutting Lakes Oahe and Francis Case, suggesting a Missouri River system-wide affect was responsible for observed population changes. Subsequently, the protective slot limit regulation was removed from Lake Sharpe in 2012.

AUTHORS: Christine Proctor, Albert Sarvis – Harrisburg University of Science and Technology

ABSTRACT: Once a widespread and common snake, the eastern massasauga (Sistrurus catenatus catenatus) is protected in every state where it currently occurs and is listed as threatened under the US Endangered Species Act. The use of drones to count wildlife is increasing, however they are primarily used to quantify conspicuous endothermic species. This ongoing study is exploring the potential of drone mounted thermal imaging to increase detection of this cryptic reptile. We hypothesized that thermal imaging captured via a remotely controlled drone will increase our ability to accurately quantify eastern massasauga populations, as compared to more traditional methods. A thermal sensor mounted to a drone was manually flown over a 20-acre managed prairie with a confirmed population of eastern massasaugas in a systematic pattern at an elevation of 10 meters, providing a ground resolution of 1.85 centimeters. Two controllers were used, allowing one person to focus on flying the drone while the other closely monitored the imagery. A third person was directed to the location of a suspected snake for visual confirmation. Once visual confirmation was made, we collected temperature data for both the snake and the ambient environment using a laser thermometer. This allowed for an increased understanding of the minimal temperature difference between the snake and ground required for detection, helping to set target temperature ranges and improve overall detection. During this process we also collected data on thermal signatures of non-snake items such as small mammals, branches, ant hills, and water, helping to train observers on how to interpret the imagery at a higher accuracy. The results from this study have the potential to improve the accuracy of data collection, influencing the future of cryptic reptile detection.

AUTHORS: David G. Fielder, Michigan Department of Natural Resources

ABSTRACT: Walleye reached recovery targets in Saginaw Bay in 2009 and a management simulation model indicated that recreational fishing mortality could be increased by as much as 50% without exceeding reference points of sustainability. Recreational harvest regulations (daily possession limit and minimum length limits) were liberalized in 2015. Monitoring and evaluation has taken the form of creel survey and a fishery independent fish community netting survey. Besides indicators from those efforts, a stock assessment model is also used to gauge mortality rates and status relevant to sustainability thresholds. While walleye harvest has increased some, recreational effort has not changed greatly and that appears to limit the magnitude of the effect. The multiple survey and modeling approach to harvest regulation monitoring is effective, but costly and requires ongoing commitment to survey work and model updating.

AUTHORS: Christopher Jacques, Western Illinois University; Evan Phillips, Colorado Parks and Wildlife; Angela Jarding, National Park Service; Susan Rupp, Enviroscapes Ecological Consulting, LLC; Robert Klaver, U.S. Geological Survey; Chadwick Lehman, South Dakota Game, Fish and Parks; Jonathan Jenks, South Dakota State University

ABSTRACT: Since 1993, elk (Cervus canadensis nelsoni) abundance in the Black Hills of South Dakota has been estimated using a detection probability model previously developed in Idaho, though are likely negatively biased because of a failure to account for visibility biases under local conditions. To correct for this bias, we evaluated the current detection probability across the Black Hills during January and February 2009-2011 using radiocollared elk. We used logistic regression to evaluate topographic features, habitat characteristics, and group characteristics relative to their influence on detectability of elk. Elk detection probability increased with less vegetation cover (%), increased group size, and snow cover (%); overall detection probability was 0.60 (95% CI = 0.52-0.68) with 91 of 152 elk groups detected. Predictive capability of the selected model was excellent (ROC = 0.807), and prediction accuracy ranged from 70.2% to 73.7%. Cross-validation of the selected model with other population estimation methods resulted in comparable estimates. Application of our model should be applied cautiously if characteristics of the area (e.g., vegetation cover > 50%, snow cover > 90%, group sizes > 16 elk) differ notably from the range of variability in these factors under which the model was developed.

AUTHORS: Andrew Carlson, Minnesota Department of Natural Resources

ABSTRACT: The science of evaluating species distributions against environmental conditions has advanced tremendously in the past decade following technological improvements in tagging and monitoring systems. Using data collected from acoustically tagged adult Walleye, generalized linear mixed models were developed to predict the probability of occurrence at depth given temperature and oxygen within stratified lakes. Following, using data from a survey-specific temperature and oxygen profile, the relative odds of occurrence for Walleye was calculated throughout the water column and at the depths of the gillnet sites. Comparisons between modeled probability of occurrence and observed catch rates at specific sites were made to evaluate the degree to which site-level patterns can be explained by the habitat sampled. Integrating and accounting for known measures of environmental variability that systematically influence catch statistics will improve the quality and subsequent interpretation fisheries data to support management decisions.

AUTHORS: Ben C. Neely, Jeff D. Koch, Connor J. Chance-Ossowski – Kansas Department of Wildlife, Parks, and Tourism

ABSTRACT: Bluegill Lepomis macrochirus contribute to unique fisheries in Kansas where they fill many niches. One niche that has been gaining recent attention from anglers is pursuit of large individuals. These efforts typically occur during the Bluegill spawn in May and June when anglers can visually target nest-guarding fish. A combination of being visually evident and aggressively defending nests makes Bluegill especially susceptible to angler harvest during this time. There is concern that harvest of nest-tending Bluegill may remove the fastest growing individuals from the population and ultimately results in populations that do not support quality Bluegill fisheries. To this end, Bluegill were sampled from 14 Kansas impoundments with both fall electrofishing at random shoreline locations and spring angling for nest-tending individuals in 2017 and 2018. Total length was recorded from all captured individuals and otoliths were collected from up to five individuals per centimeter group for age and growth estimation. In all impoundments, length distribution of sampled bluegill differed between gears with angled fish shifted toward larger individuals. Similarly, angled fish exhibited more rapid growth than randomly sampled individuals in some populations. These results highlight the vulnerability of the fastest growing individuals in bluegill populations to angler harvest while preparing and guarding spawning sites. Further, these results suggest that instituting some level of protection to nest-guarding Bluegill might result in increased size structure and promote development and maintenance of quality Bluegill fisheries.

AUTHORS: Ethan J. Kessler, Illinois Natural History Survey, University of Illinois; Kurt T. Ash, Samantha N. Barratt, Eric R. Larson – University of Illinois; Mark A. Davis, Illinois Natural History Survey

ABSTRACT: Secretive aquatic animals are often particularly difficult to sample via traditional methodologies, especially when coupled with low population densities.  Alligator snapping turtles (Macrochelys temminckii) are a fully aquatic chelonian endemic to the southeastern United States.  At the northern extent of their range (i.e. Illinois and Indiana) this species is rarely encountered, and many records are chance encounters reported by citizen scientists.  M. temminckii receive state-level protection throughout the bulk of their range and are currently under consideration for federal protection. As a consequence, documenting their occurrence across their range is a conservation imperative. Environmental DNA (eDNA) techniques detect DNA shed by animals into the environment to determine whether a species inhabits an area of interest.  Due to their low detection probability at the edge of their range, eDNA may present a cost-effective method for M. temminckii surveys. We used an ongoing M. temminckii reintroduction in Illinois to test the efficacy of eDNA methods to determine detection limits using radio-telemetered individuals. Water samples were taken from known turtle locations, as well as random locations upstream and downstream from turtles.  M. temminckii eDNA detections were positively correlated with turtle presence but showed limited downstream transport. Results from the Illinois methods-testing were applied to an eDNA survey of M. temminckii in two watersheds in Indiana, identifying locations with potential M. temminckii presence. Our results demonstrate that eDNA may be a viable means of detecting M. temminckii and could be utilized to better target areas to focus traditional sampling efforts.

AUTHORS: Andrew Bueltmann, Sandra Clark-Kolaks – Indiana Department of Natural Resources

ABSTRACT: Two entrapment gears, the Indiana Standard trap net (INS) and the Small Lake Michigan trap net (LM), were compared to evaluate which was more efficient and more cost effective for collecting Crappie. Gears were deployed randomly at four total lakes, one in 2017 and three in 2018. Efficiency was measured by effort needed to collect a similar sample size between gears along with time required to run both nets. Further, cost effectiveness was measured by the individual cost of both nets and the number of cheap nets which could be purchased for the more expensive net. Specifically, a single LM costs ~$4,500 and a single INS costs ~$500; therefore, nine INS could be purchased for one LM. Cost effectiveness was then calculated as the ratio of estimated catch:estimated labor time to run the necessary number of nets so that individual costs were equivalent (i.e., one LM to nine INS). The larger the ratio, the more cost effective the gear type. All lake data were pooled for analysis and indicate that size distribution between nets does not differ and mean overnight catch rates were nearly triple the amount higher for LM (14.8) than INS (5.6). Further, labor time required to achieve equivalent catch rates were as follows: one LM net (~9.8 to 60.4 mins to run) to three INS nets (~10.5 to 58.8 mins to run). Although mean overnight catch rate was higher for LM, cost effectiveness indicates little to no difference between the gears with INS (0.7) being slightly more cost effective than LM (0.5).

AUTHORS: Nick Kramer, Kansas Department of Wildlife, Parks, and Tourism

ABSTRACT: Gill nets are one of the most popular gears implemented to assess fish populations in North America. Ease of construction and low maintenance has led to their success and widespread implementation in the field of fisheries management. The characteristics of a gill net, along with the size and shape of the fish affect how capture occurs (i.e., wedging, gilling, tangling, or a combination). Many studies have been completed on selectivity of various sizes of mesh. Despite the importance of mesh size, the shape of the mesh can also be altered by modifying the hanging ratio which in turn will affect the catchability of fishes with differing body shapes. Additional studies have demonstrated the effectiveness of hobbling or tying down gill nets. This creates more of a “baggy” net which studies have shown to capture a wider size range of fish and may increase catches of species that could easily become tangled due to external protrusions (e.g., Channel Catfish or Paddlefish). In recent years, Kansas Department of Wildlife, Parks, and Tourism biologists have become interested in managing Blue and Flathead Catfish and have placed an increased priority on sampling these species; however, the biologists currently have little insight into fully representative population parameters due to standardized sampling gear that does not capture larger individuals. Thus, the objective of this study is to evaluate the effectiveness of various gill net designs to sample fish populations in Kansas impoundments with special consideration given to species of interest for biologists (e.g., Blue Catfish, Flathead Catfish). Year one of this study found differences in catch rates for some commonly assessed species. These differences were further examined in year two of the study by expanding the sample size; in both number of sets and number of reservoirs.

AUTHORS: Erin O'Shaughnessey, Rachel Egly, Reuben Keller – Loyola University Chicago

ABSTRACT: Crayfish are the largest freshwater invertebrate and pose a serious threat to the ecosystems in which they invade. They have been shown to decrease macroinvertebrate density and diversity, displace native crayfish, and alter fish communities. We have identified a reproducing population of red swamp crayfish (Procambarusclarkii)in the Chicago Area Waterways System (CAWS). This species has been introduced in Lake Erie, small ponds in Wisconsin, and streams in Michigan, as well as in Africa, Asia, and Europe. Due to the proximity of the CAWS to Lake Michigan and undisturbed streams with native crayfish populations, P. clarkii is potentially able to spread into more areas. During summer 2018, we began a removal effort ofP. clarkii in the North Branch of the Chicago River and in the North Shore Channel. Additionally, we tested for the optimal number of nights for traps to be left in the water to achieve the highest catch rate and used mark and recapture methods to attempt to test the distance that crayfish travel in this system. In the North Branch of the Chicago River, we have recaptured 51 crayfish, traveling an average distance of 2.53 meters per night. In the North Shore Channel, we have recaptured 11 crayfish, traveling an average distance of 6.41 meters per night. Previous sampling indicated that the average CPUE (catch per unit effort) in this system was 0.843. The current CPUE of P. clarkii in our removal study area is 0.453. 

AUTHORS: Jacob A. Shurba, Kali Rush, Jacob Straub – University of Wisconsin-Stevens Point

ABSTRACT: Since September 2017, a study was conducted to examine hen and brood survival rates of Wood Ducks (Aix sponsa) in central Wisconsin. The capturing of wood ducks during the breeding season required use of decoy traps using captive wood duck hens. These captive ducks were purchased from two game farms in the Midwest. Captive decoy hens were placed in traps to attract breeding wood ducks. In March 2018, a small number of the decoy ducks began dying with no clinical signs to diagnose what was causing the mortality. In this study, we reviewed common diseases of waterfowl, the husbandry requirements for captive waterfowl species, and produced potential explanations as to what caused captive duck mortality, as well as recommendations for future studies. We collected data based on the differences in how our ducks were housed compared to recommendations in the literature. We also reviewed the inconclusive pathology reports from the deceased ducks and compared results to common diseases found in waterfowl. We found that the conditions our decoys ducks were kept in could be improved. A combination of living conditions and the adverse effects of being a decoy bird played a significant role in the mortality of these decoy ducks. Recommendations for future studies include a change of living condition to decrease the amount of stress placed on the decoys, and to lessen the amount of time a decoy duck is spending in the trap. 

AUTHORS: Tim Lyons, Larkin Powell – University of Nebraska-Lincoln; Mark Vrtiska, Nebraska Game and Parks Commission

ABSTRACT: Bird banding is a basic but important form of population monitoring that is vital to waterfowl management in the U.S. Most often, the data derived from state and federal banding programs are used to estimate survival and harvest rates and distributions across broad geographic regions, but they can also be used to estimate abundance at more local scales. However, absent or limited population surveys, banding efforts, or recoveries, from neighboring states or provinces complicates efforts, leading to ad hoc approaches to deal with these problems during analysis. Here, we use banding and recovery data of Canada geese in Nebraska 2006-2017 to assess the effects of changing harvest regulations on Canada goose demography and estimate abundance. We demonstrate a modified harvest derivation analysis and Lincoln-Peterson estimator to address pitfalls common to these approaches when estimating abundance. Finally, we discuss Jolly-Seber models as an alternative approach to estimating demographic parameters and abundance that circumvents the need for banding or population monitoring programs out-of-state and provides greater detail about the mechanisms responsible for population changes.

AUTHORS: Jason E. Ross, Mike Seider, Jared Myers – U.S. Fish and Wildlife Service

ABSTRACT: Traditional Aquatic Invasive Species (AIS) monitoring and early detection programs in the Great Lakes target fish use multiple gears to maximize the number of species captured.  The measures of success has been measured by the proportion of the total expected species pool captured in a given period.  This same approach has been applied to aquatic macroinvertebrates, but the measures of success have not been reaching the same expectations as fish.  Aquatic macroinvertebrates are smaller, more numerous, less mobile, and far less studied than fish and, therefore, should not have the same expectations.  In this study, we evaluated our samples collected from 2014 to 2016 by taxonomic groups and gear types to determine whether sample designs were capturing taxonomic groups containing species at risk of invading Lake Superior (amphipods, bivalves, gastropods, and mysids).  We found that our gears (sweep nets, petite ponar, Hester-Dendy, Zebra Mussel Samplers) were not capturing taxonomic groups of interest with much success.  Missing taxon groups of interest in collections can greatly change accumulation curves and deprecate the success of a program.  During 2017, we added rock bags to target amphipods; Neuston nets, vertical plankton tows, and sweep nets at night to target mysids; and did not scrape the Hester-Dendy and Zebra Mussel Samplers to allow bivalves to mature for identification.  The modifications allowed us to capture two additional species of amphipods, successfully identified Zebra Mussels on samplers, and discovered Bloody Red Shrimp in the St. Louis River Estuary.  By changing the focus of the aquatic macroinvertebrates monitoring from “finding all of the species” to “targeting taxon of interest”, the measures of successes have changed to reasonable expectations while improving the monitoring of invasive species.

AUTHORS: Kevin S. Page, Ohio Division of Wildlife

ABSTRACT: Reservoirs in Ohio are surveyed annually by the Ohio Division of Wildlife (ODOW) to collect fishery-relevant information on angler effort, catch, and harvest. Historically, the ODOW conducted roving-access site angler creel surveys on weekdays and weekends during the months of April–September. However, the costs associated with conducting these intensive surveys limited the number of locations surveyed annually (0–5). In 2004, a new angler survey design was implemented that only targeted periods of greatest overall and directed angler effort (May–July, weekends), thereby decreasing the number of surveys at any one reservoir but increasing the number of reservoirs surveyed. This design has been instrumental in increasing the spatial and temporal extent of angler surveys. As of 2016, more than 300 angler surveys have been conducted at more than 100 reservoirs. To validate that the “targeted” survey design continues to provide useful fishery metrics, intensive angler surveys (March–November, weekdays and weekends) were conducted at four reservoirs during 2017. This full extensive dataset was compared to a subset representing the typical high-use survey. Overall, the “targeted” strategy continues to effectively monitor overall angler effort and catch, but may miss the peak periods (spring and fall) for certain fisheries.

AUTHORS: Luke J. Malanchuk, Michael P. Ward – Illinois Natural History Survey; Heath M. Hagy, U.S. Fish & Wildlife Service; Aaron P. Yetter, Forbes Biological Station, Frank C. Bellrose Waterfowl Research Center

ABSTRACT: The Illinois River Valley (IRV) serves as a crucial stopover area for migratory shorebirds in the midwestern United States despite the high prevalence of row crop agriculture and extensive  wetland loss and degradation in the region. Aerial surveys are commonly used to quantify waterfowl abundance and estimate population size, but few attempts have been made to evaluate aerial surveys for other guilds of wetland birds. We investigated whether aerial surveys may provide a good estimate of shorebird use of stopover sites in the IRV. During July-September 2017-2018, and April-May 2018, we conducted concurrent ground and aerial surveys at 5-7 sites per week. Additionally, a single observer counted and assigned all shorebird detections to either "large" (Killdeer (Charadrius vociferous) and larger) or "small" (Pectoral sandpiper (Calidris melanotos) and smaller) size classes, and recorded wetland habitat characteristics at a total of 96 surveyed sites in the IRV. The use of ground counts each survey allows for the calculation of aerial detection probability count bias, while using habitat data of the specific count location from the ground as a correction factor. Aerial surveys detected 89% (N = 93, Range = 0%-250%) of individuals counted during ground surveys. The total number of shorebirds counted in the IRV each week ranged from 1,705 to 30,290, with an average of 10,025 birds. Aerial surveys appear to be an accurate and efficient method to quantifying shorebird abundance along large-river systems. Future plans include questions associated with stopover duration and which species are present in the IRV.