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1.
J Wildl Dis ; 59(4): 569-576, 2023 10 01.
Article in English | MEDLINE | ID: mdl-37846910

ABSTRACT

Exposure of a dam to pathogens may potentially affect her fawns positively or negatively. Mammalian females transfer immunologic protection to their offspring via colostrum obtained while nursing. Conversely, chronic diseases in dams may potentially result in small and weak neonates, reduced milk production or quality, or infection. Little is known about how pathogen exposure in adult female white-tailed deer (Odocoileus virginianus) affects offspring survival. Our objective was to assess pathogen exposure for female white-tailed deer and subsequent survival rates of fawns in Dunn and Grant counties, North Dakota, and Perkins County, South Dakota, USA. We collected blood serum from 150 adult female deer during 2014. We compared survival of 49 fawns to maternal exposure to 10 pathogens from 37 of 150 adult females. There was no difference in fawn mass between dams based on antibody status and no difference in fawn survival for nine pathogens. The 12-wk survival for fawns born to mothers with antibodies against bovine herpesvirus 1 (BoHV-1, causing infectious bovine rhinotracheitis) was lower than for fawns born from mothers without antibodies against BoHV-1; however, the indirect or direct impacts of BoHV-1 exposure in mothers on fawn survival are unclear. Although our findings suggest that the cost of exposure to previous diseases may have minimal impact on short-term fawn survival for most pathogens, additional research with increased sample sizes is needed to confirm our findings.


Subject(s)
Deer , Cattle , Animals , Female , Electron Spin Resonance Spectroscopy/veterinary , Antibodies , Washington
2.
Ecol Evol ; 13(4): e9976, 2023 Apr.
Article in English | MEDLINE | ID: mdl-37091564

ABSTRACT

Wildlife population dynamics are modulated by abiotic and biotic factors, typically climate, resource availability, density-dependent effects, and predator-prey interactions. Understanding whether and how human-caused disturbances shape these ecological processes is helpful for the conservation and management of wildlife and their habitats within increasingly human-dominated landscapes. However, many jurisdictions lack either long-term longitudinal data on wildlife populations or measures of the interplay between human-mediated disturbance, climate, and predator density. Here, we use a 50-year time series (1962-2012) on mule deer (Odocoileus hemionus) demographics, seasonal weather, predator density, and oil and gas development patterns from the North Dakota Badlands, USA, to investigate long-term effects of landscape-level disturbance on mule deer fawn fall recruitment, which has declined precipitously over the last number of decades. Mule deer fawn fall recruitment in this study represents the number of fawns per female (fawn:female ratio) that survive through the summer to October. We used this fawn recruitment index to evaluate the composite effects of interannual extreme weather conditions, energy development, and predator density. We found that density-dependent effects and harsh seasonal weather were the main drivers of fawn fall recruitment in the North Dakota Badlands. These effects were further shaped by the interaction between harsh seasonal weather and predator density (i.e., lower fawn fall recruitment when harsh weather was combined with higher predator density). Additionally, we found that fawn fall recruitment was modulated by interactions between seasonal weather and energy development (i.e., lower fawn fall recruitment when harsh weather was combined with higher density of active oil and gas wells). Interestingly, we found that the combined effect of predator density and energy development was not interactive but rather additive. Our analysis demonstrates how energy development may modulate fluctuations in mule deer fawn fall recruitment concurrent with biotic (density-dependency, habitat, predation, woody vegetation encroachment) and abiotic (harsh seasonal weather) drivers. Density-dependent patterns emerge, presumably due to limited quality habitat, being the primary factor influencing fall fawn recruitment in mule deer. Secondarily, stochastic weather events periodically cause dramatic declines in recruitment. And finally, the additive effects of human disturbance and predation can induce fluctuations in fawn fall recruitment. Here we make the case for using long-term datasets for setting long-term wildlife management goals that decision makers and the public can understand and support.

3.
Anal Bioanal Chem ; 415(9): 1587-1588, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36881152
4.
BMC Public Health ; 22(1): 1950, 2022 10 21.
Article in English | MEDLINE | ID: mdl-36271371

ABSTRACT

BACKGROUND: Climate change poses a risk of health catastrophes and must be expeditiously addressed across the health care sector. Physicians are considered trustworthy and are well positioned to discuss climate change with patients. A unified strategy by all U.S. medical societies is essential to effectively mitigate their carbon footprint and address health concerns. METHODS: We conducted a review of the public facing websites of member organizations of the AMA House of Delegates and the AMA, which were scored based on inclusion of content related to climate change in position statements or policies, task forces or committees, patient education materials, practice recommendations and any official society publications. Membership in the Medical Society Consortium on Climate and Health or participation in the organization My Green Doctor were recorded as indicators of a commitment to providing educational resources about mitigation and adaptation to climate change. The availability of a virtual option for annual meetings, as a potential means to reduce the carbon footprint of attendees, was trended from 2021 to 2022. RESULTS: Fifty out of 111 U.S. medical organizations (45%) had at least one metric with a reference to climate change and sixty-one organizations (55%) had no evidence of such website content. Out of 111 websites, only 20% (N = 22) had position statements or policies pertaining to climate change, 11% (N = 12) had committees or task forces dealing with climate change, 8% (N = 9) provided patient education resources on climate change, 21% (N = 23) included green practice recommendations and 45% (N = 50) had an article in an official society publication addressing climate change. Only 14% (N = 15) were listed as member societies of the Medical Consortium on Climate Change and 2% (N = 2) were participating organizations with My Green Doctor. CONCLUSIONS: Viewed through the lens of medical society websites, there was a wide variation in efforts to address climate change. The high performing organizations can serve as a guide for other societies to help mitigate and adapt to the climate emergency.


Subject(s)
Climate Change , Humans
5.
Anal Bioanal Chem ; 414(24): 7001-7002, 2022 10.
Article in English | MEDLINE | ID: mdl-36117197

Subject(s)
Phosphines , Zinc Compounds
6.
Insects ; 13(8)2022 Aug 03.
Article in English | MEDLINE | ID: mdl-36005321

ABSTRACT

Grasslands in North America have declined by over 70% since industrialization of settlements due to the conversion of natural habitats to cropland and urban centers. In the United States, the federally supported Conservation Reserve Program (CRP) was created to improve water quality, reduce soil erosion, and increase native habitats for wildlife. Within these restored grasslands, ground beetles (Coleoptera: Carabidae) are a keystone invertebrate group that fill several crucial niches and may serve as bioindicators of successful land management strategies. To understand the impact of land management on ground beetles, we examined carabid beetle community responses to a grazing treatment and two plant restoration treatments with low and relatively high initial plant diversity over two field seasons. We used pitfall traps at 108 CRP sites across a 63.5 cm precipitation gradient, encompassing three grassland types. Overall, grazing and restoration treatment did not have detectable effects on carabid abundance, biomass, or diversity. Carabid communities, however, responded differently to grazing within grassland types-all three community measures increased in response to grazing in tallgrass sites only. Our short-term study suggests that moderate levels of cattle grazing do not negatively affect carabid communities and might have positive effects on abundance, biomass, and diversity in tallgrass regions.

7.
Ecol Evol ; 11(11): 6444-6455, 2021 Jun.
Article in English | MEDLINE | ID: mdl-34141230

ABSTRACT

Understanding what variables affect ungulate neonate survival is imperative to successful conservation and management of the species. Predation is commonly cited as a cause-specific source of mortality, and ecological covariates often influence neonate survival. However, variation in survival estimates related to capture methodology has been documented with opportunistically captured neonates generally displaying greater survival than those captured via aid of vaginal implant transmitters (VITs), likely because of increased left truncation observed in the opportunistically captured datasets. Our goal was to assess whether 3- and 6-month survival estimates varied by capture method while simultaneously assessing whether capture method affected model selection and interpretation of ecological covariates for white-tailed deer neonates captured from three study sites from 2014 to 2015 in North Dakota and South Dakota, USA. We found survival varied by capture method for 3-month neonate survival with opportunistically captured neonates displaying up to 26% greater survival than their counterparts captured via VITs; however, this relationship was not present for 6-month survival. We also found model selection and subsequent interpretation of ecological covariates varied when analyzing datasets comprised of neonates captured via VITs, neonates captured opportunistically, and all neonates combined regardless of capture method. When interpreting results from our VIT-only analysis for 3-month survival, we found survival varied by three time intervals and was lowest in the first two weeks of life. Capture method did not affect 6-month survival, which was most influenced by total precipitation occurring during 3 - 8 weeks of a neonate's life and percent canopy cover found at a neonate's capture site. Our results support previous research that capture method must be accounted for when deriving survival estimates for ungulate neonates as it can impact derived estimates and subsequent interpretation of results.

8.
Ecol Appl ; 31(6): e02381, 2021 09.
Article in English | MEDLINE | ID: mdl-34028912

ABSTRACT

Identifying how plant species diversity varies across environmental gradients remains a controversial topic in plant community ecology because of complex interactions among putative factors. This is especially true for grasslands where habitat loss has limited opportunities for systematic study across broad spatial scales. Here we overcome these limitations by examining restored plant community responses to a large-scale precipitation gradient under two common Conservation Reserve Program (CRP) restoration approaches. The two restoration strategies examined were CP2, which seeds a relatively low number of species, and CP25, which seeds a higher number of species. We sampled plant communities on 55 CRP fields distributed along a broad precipitation gradient (410-1,170 mm mean annual precipitation) spanning 650 km within the grassland biome of North America. Mean annual precipitation (MAP) was the most important predicator of plant species richness and had a positive, linear response across the gradient. To a lesser degree, restoration practices also played a role in determining community diversity. The linear increase in species richness across the precipitation gradient reflects the species pool increase from short to tallgrass prairie communities and explained most of the richness variation. These findings provide insight into the diversity constraints and fundamental drivers of change across a large-scale gradient representing a wide variety of grassland habitats. Across a broad environmental gradient, initial planting differences between restoration practices had lower effects on plant diversity than expected. This suggests that new strategies are needed to effectively establish diverse plant communities on large-scale restorations such as these.


Subject(s)
Environmental Restoration and Remediation , Grassland , Plants , Biodiversity , North America
9.
J Child Neurol ; 36(9): 760-767, 2021 08.
Article in English | MEDLINE | ID: mdl-33829918

ABSTRACT

Because of the COVID-19 pandemic, in-person services for individuals with neurodevelopmental disabilities were disrupted globally, resulting in a transition to remote delivery of services and therapies. For individuals with neurogenetic conditions, reliance on nonclinical caregivers to facilitate all therapies and care was unprecedented. The study aimed to (1) describe caregivers' reported impact on their dependent's services, therapies, medical needs, and impact on themselves as a result of the COVID-19 pandemic and (2) assess the relationship between the extent of disruption of services and the degree of self-reported caregiver burden. Two online questionnaires were completed by caregivers participating in Simons Searchlight in April and May 2020. Surveys were completed by caregivers of children or dependent adults with neurodevelopmental genetic conditions in Simons Searchlight. Caregivers reported that the impact of the COVID-19 pandemic moderately or severely disrupted services, therapies, or medical supports. The majority of caregivers were responsible for providing some aspect of therapy. Caregivers reported "feeling stressed but able to deal with problems as they arise," and reported lower anxiety at follow-up. Caregivers reported that telehealth services were not meeting the needs of those with complex medical needs. Future surveys will assess if and how medical systems, educational programs, therapists, and caregivers adapt to the challenges arising during the COVID-19 pandemic.


Subject(s)
COVID-19/psychology , Caregiver Burden/psychology , Caregivers/psychology , Health Care Surveys/methods , Health Services Accessibility/statistics & numerical data , Neurodevelopmental Disorders/therapy , Adolescent , Adult , Caregivers/statistics & numerical data , Child , Child, Preschool , Female , Health Care Surveys/statistics & numerical data , Humans , Male , Needs Assessment , Pandemics , SARS-CoV-2 , Surveys and Questionnaires
10.
Environ Sci Pollut Res Int ; 28(45): 64199-64205, 2021 Dec.
Article in English | MEDLINE | ID: mdl-33410084

ABSTRACT

Stabilized liquid membrane devices (SLMDs) have been used for passive integrative sampling of metals in freshwater systems. Field measurements of metal accumulation on SLMDs can provide a time-weighted average mass of labile metals over the deployment period. We exposed SLMDs in the laboratory to 0.5 µM solutions of silver, zinc, or aluminum as nitrate salts at three levels of water hardness, measuring metal accumulation every 4 days for 32 days. We saw linear accumulation in all experimental treatments, except for silver in high hardness (345.9 mg/L as CaCO3). The time-accumulation relationships indicated that metal sorption rates vary across valency with the lower valency metals generally accumulating at greater rates. Water hardness also affected accumulation rates and accumulated mass with greater rates as hardness increased for zinc and aluminum. The accumulated zinc mass at 32 days in soft water was 78% of the mass in hard water for zinc, and accumulated aluminum mass was 29% of the mass in hard water. Factors such as oleate formation on the SLMD surface and solution chemistry, including pH and chemical speciation, were evaluated in explaining our results. Our work supports that SLMDs have utility for sampling metals in freshwater over extended time periods, which may be beneficial when there is limited access to sites; it also provide important interpretive guidance for the use of SLMDs.


Subject(s)
Environmental Monitoring , Water Pollutants, Chemical , Fresh Water , Kinetics , Silver , Water Pollutants, Chemical/analysis , Water Quality
11.
J Environ Manage ; 248: 109299, 2019 Oct 15.
Article in English | MEDLINE | ID: mdl-31376608

ABSTRACT

Understanding the underlying mechanisms driving population demographics such as species-habitat relationships and the spatial scale in which these relationships occur is essential for developing optimal management strategies. Here we evaluated how landscape characteristics and winter severity measured at three spatial scales (1 km2, 9 km2, and hunting unit) influenced white-tailed deer occurrence and abundance across North Dakota by using 10 years of winter aerial survey data and generalized linear mixed effects models. In general, forest, wetland, and Conservation Reserve Program (CRP) lands were the main drivers of deer occurrence and abundance in most of the spatial scales analyzed. However, the effects of habitat features vary between the home-range scale (9 km2) and the finer spatial scale (1 km2; i.e., within home ranges). While escape cover was the main factor driving white-tailed deer occurrence and abundance at broad spatial scales, at a fine spatial scale deer also selected for food (mainly residual winter cropland). With CRP appearing in nearly all top models, here we had strong evidence that this type of program will be fundamental to sustaining populations of white-tailed deer that can meet recreational demands. In addition, land managers should focus on ways to protect other escape covers (e.g., forest and wetland) on a broad spatial scale while encouraging landowners to supply winter resources at finer spatial scales. We therefore suggest a spatial multi-scale approach that involves partnerships among landowners and government agencies for effectively managing white-tailed deer.


Subject(s)
Deer , Animals , Demography , Ecosystem , North Dakota , Seasons
12.
Sci Rep ; 9(1): 4534, 2019 03 14.
Article in English | MEDLINE | ID: mdl-30872713

ABSTRACT

Over the past decade, abnormalities have been documented in white-tailed deer (Odocoileus virginianus) in west-central Montana. Hypotheses proposed to explain these anomalies included contact with endocrine disrupting pesticides, such as imidacloprid. We evaluated the effects of imidacloprid experimentally at the South Dakota State University Wildlife and Fisheries Captive Facility where adult white-tailed deer females and their fawns were administered aqueous imidacloprid (an untreated control, 1,500 ng/L, 3,000 ng/L, and 15,000 ng/L). Water consumption, thyroid hormone function, behavioral responses, and skull and jawbone measurements were compared among treatments. Additionally, liver, spleen, genital, and brain imidacloprid concentrations were determined by an enzyme-linked immunosorbent assay (ELISA). Results indicated that 1) control deer consumed more water than treatment groups, 2) imidacloprid was present in the organs of our control group, indicating environmental contamination, 3) as imidacloprid increased in the spleen, fawn survival, thyroxine levels, jawbone lengths, body weight, and organ weights decreased, 4) adult female imidacloprid levels in the genitals were negatively correlated with genital organ weight and, 5) behavioral observations indicated that imidacloprid levels in spleens were negatively correlated with activity levels in adult females and fawns. Results demonstrate that imidacloprid has direct effects on white-tailed deer when administered at field-relevant doses.


Subject(s)
Insecticides/toxicity , Neonicotinoids/toxicity , Reproduction/drug effects , Animals , Behavior, Animal/drug effects , Deer , Female , Jaw/drug effects , Jaw/physiology , Male , Reproduction/physiology , Skull/drug effects , Skull/physiology , Thyroxine/blood , Triiodothyronine/blood
13.
PLoS One ; 14(2): e0211650, 2019.
Article in English | MEDLINE | ID: mdl-30716128

ABSTRACT

Changes in land use have resulted in range shifts of many wildlife species, including those entering novel environments, resulting in the critical need to understand their spatial ecology to inform ecosystem effects and management decisions. Dispersing elk (Cervus elaphus) were colonizing areas of suitable habitat in the Northern Great Plains, USA, resulting in crop depredation complaints in these areas. Although state resource managers had little information on these elk herds, limited evidence suggested temporal movements into Canada. We collected and analyzed essential information on home range and habitat selection for 3 elk herds residing in North Dakota. We captured 5 adult female elk in each study area, affixed global positioning system collars, and monitored them for 1 year (2016-2017). We estimated diel period, seasonal, and hunting season home ranges using Brownian Bridge Movement Models for each individual. We analyzed habitat selection using multinomial logit models to test for differences in use of land classes, and for departures from proportionate use based on random sampling; our predictor variables included individual elk, diel period, and season. Home ranges differed between the 3 herds, seasons, and diel period; gun and winter season home ranges were both larger than in summer, as was night when compared with day. Female elk generally restricted themselves to cover during the day and entered open areas at night and during winter months. Our results also suggest that elk in our study areas tended to seek more cover, and in the case of our Turtle Mountain study area, some cross into Canada during gun season. Our study provides a better understanding of the spatial ecology of elk in the Northern Great Plains while highlighting the need for enhanced international cooperative management efforts.


Subject(s)
Deer/physiology , Homing Behavior/physiology , Animals , Animals, Wild/physiology , Canada , Ecosystem , Feeding Behavior/physiology , Female , Geographic Information Systems , Models, Biological , North Dakota , Seasons
14.
PLoS One ; 13(4): e0195247, 2018.
Article in English | MEDLINE | ID: mdl-29621287

ABSTRACT

Offspring survival is generally more variable than adult survival and may limit population growth. Although white-tailed deer neonate survival has been intensively investigated, recent work has emphasized how specific cover types influence neonate survival at local scales (single study area). These localized investigations have often led to inconsistences within the literature. Developing specific hypotheses describing the relationships among environmental, habitat, and landscape factors influencing white-tailed deer neonate survival at regional scales may allow for detection of generalized patterns. Therefore, we developed 11 hypotheses representing the various effects of environmental (e.g., winter and spring weather), habitat (e.g., hiding and escape cover types), and landscape factors (e.g., landscape configuration regardless of specific cover type available) on white-tailed deer neonate survival up to one-month and from one- to three-months of age. At one-month, surviving fawns experienced a warmer lowest recorded June temperature and more June precipitation than those that perished. At three-months, patch connectance (percent of patches of the corresponding patch type that are connected within a predefined distance) positively influenced survival. Our results are consistent with white-tailed deer neonate ecology: increased spring temperature and precipitation are likely associated with a flush of nutritional resources available to the mother, promoting increased lactation efficiency and neonate growth early in life. In contrast, reduced spring temperature with increased precipitation place neonates at risk to hypothermia. Increased patch connectance likely reflects increased escape cover available within a neonate's home range after they are able to flee from predators. If suitable escape cover is available on the landscape, then managers could focus efforts towards manipulating landscape configuration (patch connectance) to promote increased neonate survival while monitoring spring weather to assess potential influences on current year survival.


Subject(s)
Animals, Newborn/growth & development , Deer/growth & development , Survival/physiology , Animals , Deer/physiology , Ecology , Ecosystem , Geography , Seasons , United States , Weather
17.
Anal Bioanal Chem ; 398(1): 11-2, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20669011
18.
Anal Bioanal Chem ; 397(1): 1-2, 2010 May.
Article in English | MEDLINE | ID: mdl-20204331
19.
Conserv Biol ; 23(2): 420-32, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19040653

ABSTRACT

Extensive habitat loss and changing agricultural practices have caused widespread declines in grassland birds throughout North America. The Flint Hills of Kansas and Oklahoma--the largest remaining tallgrass prairie--is important for grassland bird conservation despite supporting a major cattle industry. In 2004 and 2005, we assessed the community, population, and demographic responses of grassland birds to the predominant management practices (grazing, burning, and haying) of the region, including grasslands restored under the Conservation Reserve Program (CRP). We targeted 3 species at the core of this avian community: the Dickcissel (Spiza americana), Grasshopper Sparrow (Ammodramus savannarum), and Eastern Meadowlark (Sturnella magna). Bird diversity was higher in native prairie hayfields and grazed pastures than CRP fields, which were dominated by Dickcissels. Although Dickcissel density was highest in CRP, their nest success was highest and nest parasitism by Brown-headed Cowbirds (Moluthrus ater) lowest in unburned hayfields (in 2004). Conversely, Grasshopper Sparrow density was highest in grazed pastures, but their nest success was lowest in these pastures and highest in burned hayfields, where cowbird parasitism was also lowest (in 2004). Management did not influence density and nest survival of Eastern Meadowlarks, which were uniformly low across the region. Nest success was extremely low (5-12%) for all 3 species in 2005, perhaps because of a record spring drought. Although the CRP has benefited grassland birds in agricultural landscapes, these areas may have lower habitat value in the context of native prairie. Hayfields may provide beneficial habitat for some grassland birds in the Flint Hills because they are mowed later in the breeding season than elsewhere in the Midwest. Widespread grazing and annual burning have homogenized habitat-and thus grassland-bird responses-across the Flint Hills. Diversification of management practices could increase habitat heterogeneity and enhance the conservation potential of the Flint Hills for grassland birds.


Subject(s)
Birds/physiology , Conservation of Natural Resources/methods , Ecosystem , Animals , Fires , Kansas , Oklahoma , Population Dynamics , Time Factors
20.
Anal Bioanal Chem ; 386(5): 1197, 2006 Nov.
Article in English | MEDLINE | ID: mdl-16964472
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