Browsing by Subject "behavior"

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Alpha synuclein functions as a sex-specific modulator of cognition and gene expression
(2022-12) Brown, Jennifer
Neurodegenerative diseases such as Alzheimer’s and Parkinson’s impact large portions of the population. Though such diseases have distinguishing features, they also often share pathology and symptomology. Alpha synuclein (αSyn; gene SNCA) is a protein commonly found in a range of neurodegenerative conditions. αSyn can interact with tau and amyloid-beta to modulate disease phenotypes, but its normal functions remain incompletely characterized. To explore the contribution of αSyn to Alzheimer’s disease, I first asked whether reducing αSyn in a mouse model of Alzheimer’s would improve cognition. Using a translationally relevant strategy, the reduction of αSyn reveled a sex-specific effect whereby male, but not female, mice showed improved spatial memory. Follow-up studies with constitutive SNCA knockout mice revealed a previously unreported female-specific deficit in spatial learning and memory. Next, we utilized electrophysiology, immunofluorescence imaging and transcriptomics to elucidate potential mechanisms underlying this effect. Results revealed a novel impairment in long-term potentiation, as well as differential expression of genes related to learning and immune function in female mice in response to SNCA ablation. These results not only describe a novel sex-specific function of αSyn, but provide translationally-relevant information regarding the potential effects of using αSyn reduction as a therapeutic strategy for neurodegenerative conditions.
The Application of Precision Dairy Technologies to Detect Disease in Group Housed Automatically Fed Preweaned Dairy Calves
(2017-09) Knauer, Whitney
Housing preweaned calves in groups and feeding them automatically is increasing in popularity worldwide. Advantages to this management system include the reallocation of calf labor, earlier socialization of the calf as well as the ability to feed more milk more easily. Unfortunately, housing calves in groups can lead to an increased incidence of morbidity and mortality and delays in disease detection. The use of precision dairy technologies, namely automatically captured feeding behavior and body temperature data, may aid producers in earlier disease detection and intervention. However, research to date suggests that changes in feeding behavior, as currently calculated and reported by autofeeders, are neither timely nor sensitive when used screening tool to detect morbidity in group-housed calves. Furthermore, studies are lacking to evaluate the utility of using automatically captured (sensor derived) body temperature data to detect illness in calves. The overall aim of this thesis was to improve our understanding of how sensor derived observations, such as feeding behavior or rumen temperature measures, vary in sick (vs healthy) calves, and to describe the diagnostic utility of individual animal data collected from precision dairy technologies as a tool to predict and/or detect disease in group housed automatically fed pre-weaned dairy calves. We proposed to apply a different statistical methodology to individual calf feeding behaviors when summarized at both the day and visit level, and to indwelling rumen temperature bolus measures, to determine if illness events could be detected in a sensitive and timely manner as compared to clinical diagnosis by trained farm personnel. Several objectives were set to accomplish this aim, the conclusions of which will be discussed in general terms in this chapter. Opportunities for future work in this area will be discussed at the conclusion of this chapter. The first objective of this study was to describe the use and utility of individual calf day level feeding behaviors to predict and detect disease. We conducted a prospective observational cohort study on 10 farms in Minnesota (n=4) and Virginia (n=6). Calves were enrolled upon entry to the group pen and exited the study at weaning. Study technicians visited the farms to collect enrollment, calf health data as recorded by farm personnel, and feeding behavior data from automatic feeder software. A matched pair analysis was performed to describe the difference in day level feeding behaviors and morbidity in the time before and during a treatment event. The results of this study show that calves drink less milk, drink more slowly, and visit the feeder without a milk meal (unrewarded visit) less frequently in the days surrounding a treatment event then age and pen matched healthy calves. There were no differences between sick and healthy calves when rewarded visits to the feeder were considered. These changes varied by clinical disease diagnosis by farm personnel, with the earliest and most consistent changes in calves diagnosed with diarrheal disease, followed by ill thrift calves, and finally calves diagnosed and treated for respiratory disease. We then investigated the diagnostic test characteristic and timing of statistical process control (SPC) techniques applied to individual animal daily average drinking speed, milk consumption, and unrewarded visit behavior to predict and detect clinical disease as compared to a farm personnel diagnosis. Self-starting CUSUM charts were parameterized for optimal sensitivity and timing in a test set of calves, then applied to all calves. The diagnostic test characteristic when evaluating single, two way and three way combinations of feeding behaviors were investigated. These results showed that the combination of drinking speed and milk consumption interpreted in parallel combination were the most sensitive (70.9%) and timely test to detect an illness event, signaling a sick calf an average of 3 days prior to a treatment event. However, none of the predictive values of any of the single, two way, or three way combinations of feeding behavior parameters had sufficient predictive ability to be used alone without daily observations by skilled calf caregivers. The results of objective one contribute to the knowledge of daily average feeding behavior in group housed dairy calves, and is the first attempt at investigating the utility of using signals generated by statistical process control to predict and detect disease. The use of drinking speed and milk consumption in combination provide the most sensitive test, but none of the predictive values were sufficient to use this method of detection alone. Calf caregivers with good observational skills are still necessary to detect sick calves in group housing systems. The second objective of this thesis was to describe the use and utility of visit (or meal) level feeding behaviors to predict and detect disease in automatically fed group housed preweaned dairy calves. Data collected from a subset of calves from objective one was used for this study, representing 8 farms in Minnesota (n=3) and Virginia (n=5). These eight farms had the institute function installed in automatic feeder hand held devices, which was used to record individual calf visit behavior. Visit level average behaviors were averaged into six hour increments (quarter day). A matched pair analysis was used to describe the difference in quarter day visit average feeding behaviors in sick and healthy calves around the time of an illness event. These results showed that sick calves had an increase in total drinking time at the feeder and a decrease in visit average drinking speed up to 24hrs prior to clinical disease diagnosis by farm personnel. Visit average milk consumption and total time at the feeder was only different between sick and healthy calves in the 6 hour time period prior to clinical diagnosis. Statistical process control techniques were then applied to these same visit average feeding behaviors to understand the diagnostic test characteristics and timing of using this method to detect a sick calf. Self-starting CUSUM chart parameters were first optimized for sensitivity and timing in a testing subset of calves, then optimal parameters were applied to all calves in the data set. Diagnostic test characteristics and timing for visit average feeding behaviors were analyzed alone and in combination. A positive alert on a combination of drinking speed, total drinking visit time, and/or milk consumption provided a sensitively to 89% and was able to detect as sick calf an average of 6.5d prior to detection by farm personnel. However, the specificity was very poor (7.7%) and predictive values for all single and combination visit average feeding behaviors were also poor, with negative predictive values ranging from 41 – 48% and positive predictive ability ranging from 50 – 54%. The results of objective two contribute to the knowledge of visit (meal) average feeding behavior in group housed dairy calves. Overall, the use of visit average feeding behaviors had improved sensitivity and timing when compared to the aforementioned evaluation of daily average feeding behaviors. However, predictive ability of the test was not improved, suggesting that neither day-level of visit (meal) level feeding behavior data are sufficient to predict or detect disease when used as the sole method of detection. As such, daily visual observation by trained personnel will still be necessary to detect illness in calves. The third objective of this thesis was to investigate the diagnostic utility of an indwelling calf rumen temperature bolus system. As a first step, a validation study was performed to describe the performance of the bolus as compared to two reference standards. First, the bolus temperature was compared to a known water bath temperature. The bolus was well correlated to the water bath temperature over a range of biologically plausible temperatures. Second, a prospective cross sectional study was performed that compared the bolus temperature measurement to the rectal temperature in growing heifer calves and described the diagnostic test characteristics to detect a rectal temperature ≥ 39.5ºC. The bolus underestimated the rectal temperature of growing heifer calves by an average of 0.33ºC and had a poor sensitivity (29%) and positive predictive value (17%) to detect a rectal temperature ≥ 39.5ºC. As a second step in this investigation, a field study was conducted to describe the use and utility of an indwelling rumen temperature bolus system to predict and detect disease in automatically fed group housed preweaned dairy calves. A prospective cohort study was performed on two farms in MN utilizing group housing and automatic feeding. Enrolled calves were administered boluses at birth and their temperatures were automatically captured during the time they were in the group pen. Temperatures were averaged by both hour and six hour time periods. We reported a monophasic diurnal pattern of individual calf bolus temperature measurements over a 24 hour period, which varied by farm and season. Results of a matched pair analysis showed that bolus temperature was elevated 24hrs prior to clinical diagnosis by farm personnel as compared to healthy control calves, though this varied by type of disease present. When specific diseases were investigated, calves diagnosed with pneumonia and ill thrift had a bolus temperature that was elevated 24hr prior to clinical diagnosis, but calves diagnosed with diarrhea did not have different bolus temperature measures than their healthy matched control calves. Statistical process control techniques as well as threshold and deviation limits were then applied to individual calf temperature data to learn if these methods of data analysis could be applied to these bolus temperature measures to predict and detect disease in an accurate and timely manner. Results showed that no detection technique had a sufficient combination of acceptable diagnostic test characteristics and timing to be applied directly in the field. Positive and negative predictive ability of all detection techniques were poor, indicating that caution should be used in considering these methods as the false positive rate may be unacceptable for producers using these systems. In addition to the poor diagnostic test characteristics, a high rate of bolus loss (23% of calves) would also limit the utility of this system if adopted on commercial dairy farms. The results of objectives three represent the first study investigating the use and utility of an indwelling rumen temperature bolus for prediction and detection of morbidity in group housed pre weaned dairy calves. No detection method provided test characteristics that were sufficient to predict or detect disease. An unexpected result from this field study was the difference in diurnal variation in RTB measures by farm. More studies on more farms are needed to understand how ambient temperature and barn temperature are associated with calf body temperature, performance, and health.
Behavior and Bioacoustics of Invasive Silver and Bighead Carp
(2016-05) Vetter, Brooke
Invasive silver (Hypophthalmichthys molitrix) and bighead (H. nobilis) carp (collectively bigheaded carp) dominate the Mississippi River Drainage, outcompete native species, and continue to expand northward. Silver carp demonstrate an unusual jumping behavior to boat traffic. Understanding this response is important from a behavioral standpoint and critical to developing effective control methods. Experiments in outdoor concrete ponds (10 x 5 x 2 m), investigated the impact of pure tones (500 – 2000 Hz) and a recording from an outboard motor (0.06 – 10 kHz) on bigheaded carp swimming. Speakers broadcasting the sound stimuli were placed at either end of the concrete pond and bigheaded carp behavior was assessed using overhead cameras. Silver carp were consistently directed away (mean: 11.8 ± 1.3 consecutive responses) from the broadband sound (outboard motor recording) and the bighead carp were more responsive, exhibiting a median of 20.0 consecutive responses (1st Q: 12.0, 3rd Q: 23.0). However, both species were less reactive and habituated quickly to pure tones (after 1-2 trials). Field observations of silver carp jumping frequency, orientation, and direction in response to fast moving (16 – 40 km/hr) boats suggest that jumping is non-random, as the fish primarily move away from (79.8%) and behind the boat (> 90%), avoiding the area directly astern (< 4 m) in the most turbulent part of the wake. Finally, broadband sound (> 150 dB) stimulated wild silver carp to jump in a small tributary of the Illinois River. The fish demonstrated a different pattern than those reacting to the fast moving boats, with carp jumping all around the slow moving boat. This research suggests that sound can be used to alter the behavior of bigheaded carp with implications for deterrent barriers or other uses (e.g., herding fish to increase harvest).
Behavioral differences in sound detection in recently diverged cave and surface forms of Astyanax mexicanus
(2021) Kistner, Amanda R; Enriquez, Maya S; Michels, Noland O; Mensinger, Allen F
Astyanax mexicanus, or the Mexican tetra, inhabits both surface streams and cave systems, and has subsequently developed two unique morphologies: a cave morph and a surface morph. Cave morphs of the species have evolved several troglomorphic phenotypes, including vestigial eyes, reduced pigmentation, and increased olfactory and lateral line sensitivity. Interestingly, several satellite populations of surface fish were introduced to a Texas aquifer approximately 100 years ago and, following cave colonization, rapid evolution of various sensory adaptations between the cave and surface populations have been observed. Auditory evoked potential (AEP) data was collected to compare hearing sensitivities between cave and surface satellite populations, and both populations responded to sound presentation up to 4 kHz. However, because AEPs measure action potential summation to screen for frequency sensitivities, behavioral data is needed to determine absolute hearing sensitivity. The current study examines behavioral differences in sound detection between these two populations using reflexive startle behaviors to sound, namely the “C-start” escape response, which has been shown to be a reliable means of determining neurological responses to acoustic stimuli. Based on behavioral audiograms collected on satellite three populations, San Pedro Springs (cave) and Honey Creek (surface) appear to respond more readily to acoustic stimuli and habituate at a similar rate when compared to San Antonio Zoo (surface), which appear to respond less readily and habituate faster. Differences in sound pressure thresholds, as well as stimulus-response latencies between these populations, will be determined through finer volume control and modeling sub-thresholds.
Characterization of peripartum rumination and activity of cows diagnosed with health disorders postpartum
(2015-06) Liboreiro, Daniela
The objectives of the current observational study were to characterize the correlation among total serum Ca, non-esterified fatty acids (NEFA), Beta-hydroxybutyrate (BHBA) and haptoglobin concentrations and daily rumination time (DRT) and activity of periparturient cows, and to determine the association between periparturient events and peripartum DRT and activity. Holstein cows from one commercial dairy farm (nulliparous = 77, parous = 219) were enrolled into the study at approximately 21 d before expected calving date. Cows were fitted with individual Heat Rumination Long Distance system (HRLD, SCR Engineers Ltd., Netanya, Israel) from enrollment until approximately 21 � d postpartum. Blood samples collected weekly from enrollment to 21 d postpartum were used to determine concentrations of NEFA, BHBA, and haptoglobin. Blood samples collected within 72 h after calving were used to determine total serum Ca concentration. Sub-clinical ketosis was characterized by BHBA > 1,000 [mu]mol/L in any sample and sub-clinical hypocalcemia was characterized by Ca < 8.55 ng/dL within 72 h after calving. Cows were examined 1, 7 � 3 and 14 � 3 d postpartum for diagnosis of retained fetal membrane and metritis. Total Ca (r = 0.15), NEFA (r = -0.27), and haptoglobin (r = -0.18) concentrations were weakly correlated with DRT. Concentration of BHBA (r = -0.14) was weakly correlated with activity. Postpartum DRT was reduced among cows that delivered twins compared with cows that delivered singletons (385.9 � 17.1 vs 437.9 � 4.8 min/d). Prepartum (430.8 � 14. vs 465.8 � 4.19 arbitrary unit) and postpartum (480.3 � 19.4 vs. 536.5 � 5.5 arbitrary unit) activity were reduced among cows that delivered twins compared with cows that delivered singletons. Delivery of stillborn calves was associated with reduced DRT prepartum (417.0 � 23.4 vs. 478.0 � 5.9 min/d) and postpartum (386.5 � 19.3 vs 437.2 � 4.8 min/d). On the other hand, cows delivering stillborn calves had increased activity prepartum compared with cows delivering live calves (499.3 � 16.2 vs. 461.3 � 4.1 arbitrary unit). Occurrence of retained fetal membrane tended to and was associated with reduced prepartum (444.3 � 11.0 vs. 466.5 � 4.3 arbitrary unit) and postpartum (488.2 � 14.5 vs. 538.8 � 5.7 arbitrary unit) activity, respectively. Cows diagnosed with metritis had reduced postpartum DRT (415.9 � 10.1 vs 441.0 � 5.2 min/d) and activity (512.5 � 11.5 vs. 539.2 � 6.0 arbitrary unit) as compared to cows not diagnosed with metritis. Postpartum activity was reduced among cows that were diagnosed with sub-clinical ketosis (502.20 � 16.5 vs. 536.6 � 6.2 arbitrary unit). Although differences in DRT and activity between populations of cows that developed periparturient diseases and healthy cows were observed, further studies are necessary to determine whether (and how) DRT and activity data may be used to precociously diagnose individuals that will develop such periparturient diseases.
Data for Evaluation of a broadband sound projected from the gates of a navigation lock in the Mississippi River shows it to be a weak deterrent for common carp and unable to block passage
(2022-01-19) Riesgraf, Andrew T.; Finger, Jean S.; Zielinski, Daniel P.; Dennis III, Clark E.; Whitty, Jeff M.; Sorensen, Peter W.; soren003@umn.edu; Sorensen, Peter W.; University of Minnesota - Minnesota Aquatic Invasive Species Research Center
There is an urgent need to block the passage of carp and other invasive fishes through navigational locks in large rivers. Although the broadband sound of an outboard motor has been shown to strongly repel three species of carp in laboratory flumes and to a lesser extent inside of a lock chamber, it has not yet been tested to see if it can stop carp from entering a lock. To test this possibility, we attached speakers to lock gates and played the sound of an outboard motor while measuring its efficacy by tracking free-ranging transplanted tagged common carp in its vicinity. Eight groups of 20 carp were tested while the sound system was turned on and off for 2 week periods. When the sound system was on, these carp spent approximately one-third less time in front of the gates than when it was off which when modeled by GLMM was shown to no greater than the effects of river discharge or temperature. Further, there was no indication that this sound blocked carp from entering and presumably passing through the lock. However, the number of times that tagged carp entered the lock was low even when the sound was off. A number of factors may have contributed to the limited efficacy of this deterrent system including the sound itself.
An evaluation of the redistributive effects of a tax reform in the Dominican Republic through microsimulation models with behavioral responses
(2021-05) Goris, Camila
This paper employs microsimulation methods to assess redistributive effects of the implementation of two separate fiscal reforms in the Dominican Republic, one altering the personal income tax and another altering value added taxes. For the former, behavioral responses are estimated through a discrete choice labor supply model with formal and informal hour points in the choice set and through the calibration of elasticities of hours with respect to remuneration and with respect to non-labor income. For the latter, the AIDS model is employed to estimate price elasticities of 12 consumption groups. In both reform scenarios, results highlight the role of informal markets as a progressivity driver, as it serves as a tax burden mitigation mechanism for households in the poorest quintiles, allowing that, when all households are made worse-off after a tax reform, relative tax burdens remain progressive.
Heritability of Behavioral and Brain Measures in a Large Cohort of Healthy Twin and non-Twin Subjects
(2020-01) Joseph, Jasmine
This research investigated comprehensively the effects of genetics on behavioral traits, brain structure and function, and their associations in a large cohort of monozygotic (MZ) twins, dizygotic (DZ) twins, non-twin siblings (SIB) and non related (NR) individuals (N = 1206, total) provided by the Human Connectome Project (HCP). All primary measures available are of the highest quality and quantitatively assessed. They include the following for each individual: (a) Measures of behavioral traits in 5 domains (motor, sensory, cognitive, emotion, and personality); (b) volumes of 70 cortical brain areas extracted from high-resolution (0.7 mm isotropic) structural magnetic resonance imaging (sMRI) data; (c) resting-state blood oxygenation level dependent (BOLD) activity of the same areas extracted from long-duration (1200 volumes), fast-acquisition (every 0.72 s), high-resolution (2 mm isotropic) functional MRI (fMRI) data; and (d) white matter integrity measures (fractional anisotropy [FA] and mean diffusivity [MD] for 7 brain regions regions) derived from high angular resolution diffusion imaging (HARDI) MRI (dMRI) data at 1.25 mm spatial resolution and very strong magnetic field gradients at (100 mT/m). Data extraction and preprocessing was performed using a dedicated 704-processor high-performance computer cluster at the Brain Sciences Center using Matlab. Univariate and multivariate statistical analyses were carried out in personal computers using Matlab and IBM-SPSS (version 24). These analyses include the following. (a) Computation of common univariate statistics (mean, variance, etc.); (b) computation of intra class correlation (ICC) for each of the 4 genetic groups (MZ, DZ, SIB, NR) and its z-transform [zICC = atanh(ICC)] for each primary measure above; (c) analysis of variance (ANOVA) of zICC across genetic groups for each measure; (d) computation of heritability using Falconer’s formula; (e) multidimensional scaling (MDS) and hierarchical tree clustering (HTC) of this heritability for the different data sets (behavioral, sMRI, fMRI, dMRI). These analyses yielded substantial new information on the effects of genetics on brain and behavior, and partially elucidated underlying associations among the various diverse measures above. To our knowledge, this is the first such comprehensive study carried out.
Increasing environmental knowledge and effecting change in lawn maintenance behavior among homeowners
(2015-12) Leslie, Madeline
The management of private property in urban areas can greatly influence the amount of fertilizer, soil, and water runoff into surrounding watersheds, increasing nitrogen and phosphorus pollution and creating eutrophic conditions in water bodies. Lawns are a prominent component of managed landscapes, and as such can play a role in water pollution levels over time. Encouraging beneficial maintenance behaviors has the potential to reduce nutrient runoff from turfgrass areas and increase the ecosystem services they provide. However, there are complex reasons why private property owners make lawn and yard care decisions. In addition, members of the public often do not understand the path water travels when it leaves their property. Therefore, the objectives of this study are to assess whether or not an individual’s possession of inaccurate water pathway knowledge is related to their lawn and yard maintenance behavior, as well as to determine the effectiveness of video and written educational interventions in changing the behavior and intent to behave of individuals. Surveys of Twin Cities Metro Area, MN residents were conducted 2014 and 2015. Based on their answers, respondents were divided into two groups; those who had obvious misconceptions about runoff water pathways and those who did not. Approximately 32% of survey participants had misconceptions about runoff water pathways. In addition, there were significant differences regarding about the effects of maintenance activities, as well as the frequency of lawn watering, mowing, and fertilizer use. A follow-up survey of the June, 2014 respondents did not indicate a change in maintenance behavior after viewing the educational video, but a comparison between two intervention methods on influencing and individual’s intent to behave found that a written intervention was more effective than video. This information will help inform and direct public outreach and education efforts to help improve local water quality in urban areas.
An Investigation Into the Validity of Using a CSA to Inform Hypotheses Regarding Student Behavior
(2015-05) Peterson, Meredith
Identifying the functions of challenging behavior can lead to interventions that can be effective in decreasing challenging behavior in students, thus leading to improved academic and social outcomes. The purpose of this study was to determine the degree to which a contingency space analysis (CSA) could lead to effective intervention for challenging behavior of middle school students in a general education classroom. Participants were four middle school students, previously identified by their classroom teachers to engage in persistent patterns of challenging behavior. A CSA was conducted with each participant and hypotheses as to the functions of each participants’ behavior were developed. Interventions targeting the functions of teacher attention, peer attention, and escape were then implemented and the results were compared to those of the CSA. Results indicated that the CSA accurately predicted the most effective intervention for three of the four participants.
A Summary of African American Travel Interests and Behaviors
(University of Minnesota Tourism Center, 2014) Benavides, Julia
This report provides a brief outline of the existing and potential domestic travel market among African Americans in the United States. Demographics, income information, and basic trip characteristics are presented.
Using Movement Behavior Of Adult Female Moose To Estimate Survival And Cause-Specific Mortality Of Calves In A Declining Population
(2017-09) Obermoller, Tyler
Low calf production and survival can contribute to ungulate population declines and sustained low numbers. Continuing research on cause-specific mortality and annual survival of moose (Alces alces) calves in northeastern Minnesota is critical to understanding the long-term trajectory of the population. Beginning in late April 2016, 35 global positioning system (GPS)-collared adult females were computer-monitored for calving movements, a long distance movement followed by an intense localization. I observed 28 of 33 (85%) females make a calving movement, and with additional field observations of calves, determined 31 of the 35 (89%) females were pregnant. Mean birth-date was 12 May 2016 (median = 11 May 2016, range = 24 Apr ̶ 10 June. In 2013–2014, I observed an unusual behavior by dams, a “mortality movement,” associated with the death of their neonate. The dam made a rapid, long-distance movement (“flee”), followed by a return to the calf mortality site. In 2016, using this behavior as a calf mortality indicator, I documented evidence of 15 mortalities at a mean age of 30.6 days (± 15.5 [SE], range = 3–243 days). Based on observations of mortality movements, 21 investigations were launched and resulted in confirmation of 11 of the 15 calf mortalities. Specific causes of mortality included 9 wolf (Canis lupus)-kills, 3 black bear (Ursus americanus)-kills, 1 unknown predator-kill, and 2 deaths following vehicle collisions. Predation accounted for 87% of all mortalities. The cumulative probability of calves being killed by wolves and bears was 33% and 11%, respectively. The mean distance dams fled after a mortality was 1,873 m (± 412, range = 126–5,805 m, n = 14). Dams that made return visits returned a mean 2.8 times (± 0.5, range = 1–5, n = 8) to the mortality site. Dams returned to within a mean 106 m (± 22, range = 34–230 m, n = 8) from the mortality site. Calf survival to 30 days of age was 67% (± 8, 95% CI = 53–84%, n = 36). Survival declined to 33% (± 8, CI = 20–53%, n = 36) at almost 1 year of age, associated with an estimated calf:cow ratio of 0.35. I developed 2 population-level movement models to improve efficacy of the mortality movement for identifying calf mortalities during the first summer of life. The first approach, a temporal-based model, used a single, estimated movement velocity threshold (164 m/hr) for the dam to indicate calf mortality and accurately predicted survival status 51% of the time. My second approach, an age-specific model, using different thresholds (28–135 m/hr) for the dam relative to calf age, was 80% accurate. Using movement behavior of dams to assess calf mortality can yield important insights into mechanisms related to the decline of the population in northeastern Minnesota and aid in future management decisions.

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