Now showing items 1-20 of 9491

    • Using line acceleration to measure false killer whale (Pseudorca crassidens) click and whistle source levels during pelagic longline depredation

      Wild, Lauren; Straley, Janice M.; Barnes, Dustin; Bayless, Ali; O'Connell, Victoria; Oleson, Erin; Sarkar, Jit; Behnken, Linda; Falvey, Dan; Martin, Sean; et al. (Acoustical Society of America, 2016-11-22)
      False killer whales (Pseudorca crassidens) depredate pelagic longlines in offshore Hawaiian waters. On January 28, 2015 a depredation event was recorded 14m from an integrated GoPro camera, hydrophone, and accelerometer, revealing that false killer whales depredate bait and generate clicks and whistles under good visibility conditions. The act of plucking bait off a hook generated a distinctive 15 Hz line vibration. Two similar line vibrations detected at earlier times permitted the animal’s range and thus signal source levels to be estimated over a 25-min window. Peak power spectral density source levels for whistles (4–8 kHz) were estimated to be between 115 and 130 dB re 1 lPa2/Hz @ 1 m. Echolocation click source levels over 17–32 kHz bandwidth reached 205 dB re 1lPa @ 1 m pk-pk, or 190 dB re 1lPa @ 1 m (root-meansquare). Predicted detection ranges of the most intense whistles are 10 to 25 km at respective sea states of 4 and 1, with click detection ranges being 5 times smaller than whistles. These detection range analyses provide insight into how passive acoustic monitoring might be used to both quantify and avoid depredation encounters.
    • Summary of Reported Whale-Vessel Collisions in Alaskan Waters

      Neilson, Janet L.; Gabriele, Christine M.; Jensen, Aleria S.; Jackson, Kaili; Straley, Janice M. (Hindawi Publishing Corporation, 2012-03-26)
      Here we summarize 108 reported whale-vessel collisions in Alaska from 1978–2011, of which 25 are known to have resulted in the whale's death. We found 89 definite and 19 possible/probable strikes based on standard criteria we created for this study. Most strikes involved humpback whales (86%) with six other species documented. Small vessel strikes were most common (<15 m, 60%), but medium (15–79 m, 27%) and large (≥80 m, 13%) vessels also struck whales. Among the 25 mortalities, vessel length was known in seven cases (190–294 m) and vessel speed was known in three cases (12–19 kn). In 36 cases, human injury or property damage resulted from the collision, and at least 15 people were thrown into the water. In 15 cases humpback whales struck anchored or drifting vessels, suggesting the whales did not detect the vessels. Documenting collisions in Alaska will remain challenging due to remoteness and resource limitations. For a better understanding of the factors contributing to lethal collisions, we recommend (1) systematic documentation of collisions, including vessel size and speed; (2) greater efforts to necropsy stranded whales; (3) using experienced teams focused on determining cause of death; (4) using standard criteria for validating collision reports, such as those presented in this paper.
    • Seasonal presence and potential influence of humpback whales on wintering Pacific herring populations in the Gulf of Alaska

      Straley, Janice M.; Moran, John M.; Boswell, Kevin M.; Vollenweider, Johanna J.; Heintz, Ron A.; Quinn II, Terrance J.; Witteveen, Brianna Harmony; Rice, Stanley D.; Moran, J. R. (2018-01)
      This study addressed the lack of recovery of Pacific herring (Clupea pallasii) in Prince William Sound, Alaska, in relation to humpback whale (Megaptera novaeangliae) predation. As humpback whales rebound from commercial whaling, their ability to influence their prey through top-down forcing increases. We compared the potential influence of foraging humpback whales on three herring populations in the coastal Gulf of Alaska: Prince William Sound, Lynn Canal, and Sitka Sound (133–147°W; 57–61°N) from 2007 to 2009. Information on whale distribution, abundance, diet and the availability of herring as potential prey were used to correlate populations of overwintering herring and humpback whales. In Prince William Sound, the presence of whales coincided with the peak of herring abundance, allowing whales to maximize the consumption of overwintering herring prior to their southern migration. In Lynn Canal and Sitka Sound peak attendance of whales occurred earlier, in the fall, before the herring had completely moved into the areas, hence, there was less opportunity for predation to influence herring populations. North Pacific humpback whales in the Gulf of Alaska may be experiencing nutritional stress from reaching or exceeding carrying capacity, or oceanic conditions may have changed sufficiently to alter the prey base. Intraspecific competition for food may make it harder for humpback whales to meet their annual energetic needs. To meet their energetic demands whales may need to lengthen their time feeding in the northern latitudes or by skipping the annual migration altogether. If humpback whales extended their time feeding in Alaskan waters during the winter months, the result would likely be an increase in herring predation
    • Using movements, genetics and trophic ecology to differentiate inshore from offshore aggregations of humpback whales in the Gulf of Alaska

      Witteveen, Briana Harmony; Straley, Janice M.; Chenoweth, Ellen M.; Baker, C. Scott; Barlow, Jay; Matkin, Craig O.; Gabriele, Christine M.; Neilson, Janet L.; Steel, Debbie J.; von Ziegesar, Olga; et al. (Inter-Research Science Publisher, 2011-09-23)
      Humpback whales Megaptera novaeangliae have been studied in the coastal waters of the Gulf of Alaska (GOA) since the late 1960s, but information about whales foraging offshore is limited. A large-scale collaborative project (SPLASH) provided opportunities to study humpback whales in both inshore and offshore habitats. Using identification photographs and biopsy samples, we explored individual movements, the distribution of mitochondrial (mtDNA) haplotypes, and trophic levels for humpback whales within 3 regions (Kodiak, KOD; Prince William Sound, PWS; and southeastern Alaska, SEAK) of the GOA to determine whether inshore and offshore aggregations of humpback whales are distinct. Each region was divided into inshore and offshore habitats, creating 6 subregions for comparison. Results documenting 2136 individual whales showed that movement within the study area was most frequent between inshore and offshore subregions within a region. In general, movement between regions was minimal. Tissue samples of 483 humpback whales included 15 mtDNA haplotypes. Pairwise chi-squared tests showed haplotype differences between subregions, but inshore PWS was the only subregion with a haplotype composition significantly different than all other subregions. Trophic levels, as inferred from stable nitrogen isotope ratios, were significantly different among subregions, ranging from 3.4 to 4.5. Pairwise comparisons showed that inshore PWS was again the only subregion that significantly differed from all others. Results suggest that the combined inshore and offshore habitats for KOD and the inshore and offshore habitats for SEAK should each be considered as single regional feeding aggregations, while inshore PWS may represent a separate aggregation from PWS offshore.
    • Depredating sperm whales in the Gulf of Alaska: local habitat use and long distance movements across putative population boundaries

      Straley, Janice M.; Schorr, G. S.; Thode, A. M.; Calambokidis, J.; Lunsford, C. R.; Chenoweth, Ellen M.; O'Connell, V. M.; Andrews, R. D. (Inter-Research Science Publisher, 2014-05-08)
      Satellite tags were attached to 10 sperm whales Physeter macrocephalus (1 whale was tagged in 2 different years) to determine the movements of sperm whales involved in removal of sablefish from longline fishing gear in the Gulf of Alaska (GOA). Tags transmitted from 3 to 34 d (median = 22) in 2007 and 7 to 158 d (median = 45) in 2009. Seven whales stayed in the GOA; all were associating with fishing vessels along the slope. Two whales headed south in June shortly after being tagged; one reached the inner third of the Sea of Cortez; the other’s last location was offshore Mexico at 14°N. A third whale stayed in the GOA until October and then headed south, reaching central Baja, Mexico, 158 d after tagging. The whales that travelled to lower latitudes followed no pattern in timing of departure, and at least 2 had different destinations. All whales passed through the California Current without stopping and did not travel to Hawaii; both are areas with known concentrations of sperm whales. Whales travelled faster when south of 56°N than when foraging in the GOA (median rate of median horizontal movement = 5.4 [range: 4.1 to 5.5] and 1.3 [range: 0.6 to 2.5] km h−1, respectively). Tagged sperm whales primarily travelled over the slope, but one spent considerable time over the ocean basin. Information on the timing and movement patterns of sperm whales may provide a means for fishermen to avoid fishing at whale hot spots, potentially reducing interactions between whales and fishermen.
    • Local recruitment of humpback whales in Glacier Bay and Icy Strait, Alaska, over 30 years

      Pierszalowski, Sophie P.; Gabriele, Christine M.; Steel, Debbie J.; Neilson, Janet L.; Vanselow, Phoebe B. S.; Cedarleaf, Jennifer A.; Straley, Janice M.; Baker, C. Scott (2016-03-15)
      We provide new information on the scale at which fidelity and recruitment underlie observed increases in humpback whale Megaptera novaeangliae populations. We used photoidentification records and DNA profiles from whales in Glacier Bay and Icy Strait (GBIS), southeastern Alaska (SEAK) to investigate 3 sources of population increase over 33 yr (1973−2005): local GBIS recruitment, recruitment from elsewhere in SEAK, and immigration from outside SEAK. We defined 2 temporal strata for these longitudinal records: ‘founder’ individuals identified from 1973 to 1985 (n = 74; n = 46 with DNA profiles) and ‘contemporary’ individuals identified from 2004 to 2005 (n = 171; n = 118 with DNA profiles). To distinguish between local recruitment and recruitment from elsewhere in SEAK, we estimated the proportion of the contemporary stratum that was either a returning founder or descended from a founder female. After excluding 42 contemporary whales without a known mother or genotype to infer maternity, 73.6% of the contemporary stratum was confirmed or inferred through parentage analysis to be either a returning founder or a descendant of a founder mother. Of the 25 females with genotypes in the founder stratum, 24 (96%) were either represented in the contemporary stratum, had at least 1 descendant in the contemporary stratum, or both. We found no significant differences in microsatellite allele or mtDNA frequencies between the strata, suggesting little or no immigration from other feeding grounds. Our results highlight the importance of local habitat protection for a recovering species with culturally inherited migratory destinations.
    • Mesoscale modeling study of a polar low in the Chukchi and Beaufort Seas

      Moreira, Paula Doubrawa; Zhang, Xiangdong (2011-12)
      Polar lows are intense mesoscale maritime cyclones, often associated with strong winds that can damage high-latitude coastal environments and infrastructure. These systems have been historically infrequent in the Chukchi and Beaufort seas, but this behavior is expected to change along with the amplified changes in Arctic climate. This study investigates the unusual occurrence of a polar low in this region on October 9-10, 2009. Sensitivity experiments with the Weather Research and Forecasting model indicate that using ERA-Interim as large-scale forcing and performing spectral nudging at all simulation hours yield the most realistic simulation. The simulations are highly sensitive to physical parameterizations, where Morrison rnicrophysics and Yonsei University boundary layer produce the smallest errors. Surface forcings were not important for the polar low development and their influence could not extend above 850 hPa due to a stable lower atmosphere. A convergence zone between the Aleutian Low and the Beaufort High established a southerly flow that created favorable conditions by continuously adverting heat and moisture from lower latitudes. The polar low had a hybrid development and was likely triggered by the interaction between a deep-penetrating upper-level potential vorticity anomaly and a low-level baroclinic zone, which were driven northward by the jet stream.
    • Ecosystem response persists after a prolonged marine heat wave

      Suryan, R. M.; Arimitsu, M. L.; Coletti, H. A.; Hopcroft, R. R.; Zador, S. G.; Lindeberg, M. R.; Straley, Janice M. (Nature Research, 2021-03-18)
      Some of the longest and most comprehensive marine ecosystem monitoring programs were established in the Gulf of Alaska following the environmental disaster of the Exxon Valdez oil spill over 30 years ago. These monitoring programs have been successful in assessing recovery from oil spill impacts, and their continuation decades later has now provided an unparalleled assessment of ecosystem responses to another newly emerging global threat, marine heatwaves. The 2014–2016 northeast Pacific marine heatwave (PMH) in the Gulf of Alaska was the longest lasting heatwave globally over the past decade, with some cooling, but also continued warm conditions through 2019. Our analysis of 187 time series from primary production to commercial fisheries and nearshore intertidal to offshore oceanic domains demonstrate abrupt changes across trophic levels, with many responses persisting up to at least 5 years after the onset of the heatwave. Furthermore, our suite of metrics showed novel community-level groupings relative to at least a decade prior to the heatwave. Given anticipated increases in marine heatwaves under current climate projections, it remains uncertain when or if the Gulf of Alaska ecosystem will return to a pre-PMH state.
    • Alaska Earthquake Center: A 2020 Perspective

      Grassi, Beth; West, Michael; Gardine, Lea (2021-03)
      The Alaska Earthquake Center is not historically in the habit of producing annual reports. We are in a dynamic time, however. Societally-significant earthquakes and multiple tsunami concerns over the past few years have brought more attention to what we do. At the same time, we are experiencing significant growth in several areas. Our goal in distributing this summary is to communicate the breadth of our activities and the diversity of our stakeholders, helping us become even more effective at meeting the earthquake and tsunami science needs of Alaska and the nation.
    • Improving Emergency Airway Care at a Critical Access Hospital

      Mitchell, Kelly (University of Alaska Anchorage, 2020-12-01)
      Emergency airway care is of the highest priority in caring for patients arriving at the emergency department with critical injuries and conditions. Intubation via laryngoscopy is the gold standard for placing an endotracheal tube to manage ventilation. In rural areas, emergency airway care is often the responsibility of non-expert providers who rarely have the opportunity to perform this life-saving procedure. These less experienced providers often take a longer time and make more attempts at endotracheal intubation. Multiple attempts and increased time taken to secure an airway are associated with higher morbidity and mortality. A critical review of the literature supports that video laryngoscopy increases first pass endotracheal intubation success. Video laryngoscopy is associated with faster intubation times and an improved view of glottic structures. This evidence-based quality improvement project implemented training and simulation in the use of video laryngoscopy for non-expert providers. After implementation of this quality improvement project, findings demonstrated an improved confidence with use of video laryngoscopy, increased confidence that video laryngoscopy is associated with improved visualization of glottic area and increased confidence associated with first pass of the endotracheal tube in non-expert providers using laryngoscopy to perform endotracheal intubation.
    • Legacy junk: MFA thesis exhibition

      Juneau, Allison; Mollett, David; Jones, Zoe; Mehner, Da-ka-xeen (2020-12)
      I recently purchased a tract of raw land with the intention of building a cabin, and wasn't terribly surprised to find the land came with some impressive piles of junk. I was frankly enamored of these objects, abandoned but not destroyed by the previous owner. They had a potentially useful quality that resonated with other aspects of the Fairbanks community; transfer sites, the airplane graveyard behind the airport, old couches and tables and wooden spools that littered the yards of countless homes. This rural detritus represents a confluence of natural and cultural forces that Alaskans experience every day. I wish to investigate this transitional territory by abstracting and amplifying the fine line between usefulness and decay. I believe that in this modern life, it is all too easy to assume that the world of nature and the world of human culture are totally separate. For me, this assumption was repeatedly challenged after experiencing the destructive power of nature during my childhood in Tornado Alley, and more recently, the subzero temperatures of Interior Alaska. I typically draw inspiration from daily observations of my environment, and as a result my imagery changed dramatically after I moved to the far North. Despite the change of landscape, the core concept of investigating intersections of nature and culture remains the same. This is a fascinating task in the Alaskan Interior, as these intersections are clearly exposed. This community has a unique relationship to nature, as modern homes and businesses coexist with virtually untouched wilderness. These experiences have instilled in me a deep respect for the vast web of life that both supports and threatens my community, and motivates me to seek out and emphasize places where natural and artificial worlds collide using the malleable language of art and oil painting.
    • VITAS: A Visual Exhibit

      Walter, Ilisa A.; Croskrey, Wendy E.; Jones, Zoë M. (2020-12)
      VITAS is a visual exhibition that addresses the idea of a posthumous legacy. The substance of a person’s life is composed of what they’ve done, and what they become after death is determined by that substance. This exhibition is composed of 25 carved animal skulls and sculptures inspired by the concept of vitas, treating life as an opportunity to advance the next generation through life’s work. VITAS studies the idea of what happens after the passing of a being by applying embellishment, adornment, pigments, and carvings onto the skeletal remains of animals. By applying human influence to natural material, the animal’s experience becomes a vital part of the artwork. Bone density, size, condition, and abnormalities are all determined by how the animal lived. These factors are a major consideration in design and aesthetic choices in each unique piece.
    • Nome Eskimo Community Tribal Council Resource Guide

      Nichols-Takak, Kendra Kookruk; Brooks, Cathy; Stern, Charlene; Topkok, Megan (2020-12)
      The Nome Eskimo Community Tribal Council Resource is a digital manual composed of information for newly elected tribal leaders so they can provide the best guidance to the Tribe, develop leadership skills, and serve the community. The purpose of this project is to ensure that current and future tribal council members and presidents have access to information necessary to make decisions on important issues using best practices for governance and leadership. The resource guide includes roles and responsibilities as well as local and statewide resources in various areas of governance including child welfare, land, natural resources, and education. It is intended to provide a starting point for newly elected tribal members. Additionally, Nome Eskimo Community (NEC) bylaws, program information, photos and recorded interviews of current and former tribal leaders will provide newly elected officials with important NEC history. The different subjects contained within the guide are specific to the programs the Council is governing. Leaders have access to the digital resource guide via downloadable files which can be viewed on a tablet. The resource guide will include the roles and responsibilities of the tribal council and the president and will cover governance, leadership practices, and program resources. The resource guide can be further developed to include advanced information for experienced leaders in the following areas: child welfare, land, natural resources, and education.
    • Creating safety policy and procedures in an active shooter event

      Nash, Mechelle L.; Taylor, Karen; DeCaro, Peter; Hum, Richard; Heckman, Daniel (2020-12)
      School and workplace active shootings are on the rise and seem to be the norm today and there is not a working policy in place to train for an active shooter event in our organization, Golden Valley Electric Association. The purpose of this project was to develop a workable policy and procedure for the employees and to enhance the safety culture within our organization. To achieve this goal, a training presentation was created using the ALICE Training Institute’s protocol to train the workforce. The ALICE acronym stands for A=Alert, L=Lockdown, I=Inform, C=Counter, E=Evacuate. Over the course of research for this project, research indicated that a crisis management plan (CMP) and crisis management team (CMT) would be a better option for training the organization, not policies and procedures. A sample crisis management plan and outline for the crisis management team were created. The crisis management team would deal with the policies and procedures and ensure the success of training the workforce and enhancing the safety culture of the organization. The recommendations are for the organization to select the CMT, review the CMP created, and implement and maintain the plan. Following and implementing these recommendations into practice would ensure the workforce was trained and would strengthen the safety culture of the organization.
    • A Place-based study of Alaskan animals

      Heslop, Emma; Hogan, Maureen; Hornig, Joan; Kardash, Diane (2020-12)
      In the spring of 2020, my second-grade class, located in Fairbanks, AK, dived into a place-based exploration of Alaskan animals. The aim of the project was to increase students’ connections and understanding of the state where they live (Alaska) and the animals that they share it with. Through a backwards design, inquiry-based instructional model, my students met state standards with an integrated-subject approach. With art, guest speakers, research, and field trips my students learned about the Animals that share Alaska with us, their environments, and their adaptations. Students used informational writing published on digital mediums to share their knowledge with others. I propose to share this unit with other educators in the form of a website with links and lesson plans so that more teachers and children have access to quality place-based materials that align to state standards.
    • Measuring the impact of cooperative rewards on AI

      Harmon, Dain; Lawlor, Orion S.; Chappell, Glenn G.; Metzgar, Jonathan B. (2020-12)
      We consider the effects of varying individualistic and team rewards on learning for a Deep Q-Network AI in a multi-agent system, using a synthetic team game ‘Futlol’ designed for this purpose. Experimental results with this game using the OpenSpiel framework indicate that mixed reward structures result in lower win rates. It is unclear if this is due to faster learning on simpler reward structures or a flaw in the nature of the reward system.
    • Review and case study of electric submersible pump performance with dispersions

      Ellexson, Dexter Bryant; Awoleke, Obadare; Ning, Samson; Dandekar, Abhijit (2020-12)
      Centrifugal pump performance is very sensitive to fluid viscosity, gas fraction, and flow pattern in impeller channels. Viscous oil reduces the head and rate capacity of the pump. High gas fraction reduces the head capacity of the pump at high rates and leads to unstable surging at low rates. If the flow pattern in the impeller transitions to an elongated bubble the pump can gas-lock causing loss of production and excessive heat buildup. The complex geometry and 3-dimensional flow in a pump stage make the analysis of flow in a pump difficult without simplifying assumptions. Empirical and mechanistic models have been developed for correcting pump performance for viscosity, gas fraction, and predicting flow pattern within the impeller with reasonable accuracy. Difficulties arise when produced fluids form stable dispersions. Foams, emulsions, and solid suspensions make the determination of viscosity, gas separation efficiency, and flow pattern more difficult. Interfacial properties between phases become important in determining the bulk fluid properties, and the presence of surfactants exacerbates the interfacial effects. The objective of this project is to describe the fundamentals of electrical submersible centrifugal pumps, ESPs, and the effects that produced fluids have on their performance. These findings are then used to evaluate a case study of an ESP installed in a well with foamy and viscous crude. The ESP exhibits reduced head and rate compared to predicted viscous and gas corrections. Including interfacial effects on the fluid viscosity allow a satisfactory performance match of pump performance to be achieved. The effect of foam on pump performance can be attributed to the increased viscosity exhibited when gas behaves as a dispersed phase in a continuous oil phase rather than a separate phase in a mixture.
    • The Ranch(er)

      Connelley, Wendy; Brashear, James; Mehner, Da-ka-xeen; Croskrey, Wendy Ernst; Jones, Zoë Marie (2020-12)
      THE RANCH(ER) is a thesis project to fulfill the requirements of an MFA degree in visual fine-arts. This project focused on exploring my connection between the land, the ranch and its tools, and generations of ancestors living and working a small family ranch. I give voice to the seldom-vocal rancher and the isolation, hardships, and tenderness of ranch life. I have chosen as subjects for this exhibition objects that are utilitarian and are items woven into the cultural fabric of ranchers and their families. They are icons of generational identity. Rather than creating purely traditional functional objects such as cups and bowls, I’ve created conceptual pieces that emphasize the intangible connection between utilitarian objects and their users, as well as the objects’ roles in its customary position. By removing the items from their original context, I point to the context of function and utility: a life of use and work. Clay is the primary material used to create this installation to tell a universal story. The ceramic and sculptural pieces were exhibited to the public as an installation in the University of Alaska Fairbanks Fine Arts Gallery in the Fine Art Complex, Room 312, from November 2-20, 2020. The artist’s public presentation was given through an open Zoom meeting on Friday, November 13, 2020. The project report summarizes the examination and investigations involved in the development of the project.
    • Automated remote security scoring engine (ARSSE): gamification of cyber security education

      Chauhan, Arsh; Lawlor, Orion S.; Hartman, Christopher M.; Metzgar, Jonathan B. (2020-12)
      The goal of this project is to create an easy to use, extensible, and engaging method to compute scores interactively during a practical cyber security education. Gamification has been shown to be an effective teaching tool and has been used in the offensive cybersecurity education space (via Capture The Flag competitions and challenges such as hackthebox.eu) but there has not been an open-source effort to bring this idea to the defensive side (blue team) aspect of cybersecurity. The Automated Remote Security Scoring Engine (ARSSE, pronounced "Arsh") uses a combination of well maintained open-source tools and custom connectors to facilitate an easy to use, scalable, and secure system to check the state of a computer system against a desired state and award points based on passed checks. ARSSE has been released to the public with the hope that it will fill a gap in training the next generation of information security professionals.
    • Recommendations for training of substitute teachers in the Matanuska-Susitna Borough School District

      Chamblee, Lulu R.; Topkok, Sean; Hornig, Joan; Kardash, Diane (2020-12)
      With increasing importance placed on student growth and achievement scores, increasing teacher absenteeism, and increasing amounts of time students spend being taught by substitute teachers, it is surprising that the preparation of substitute teachers does not reflect the significance of the job they have in relation to these trends. Research shows that training can increase substitute teacher effectiveness, which may positively affect student growth and achievement. The purpose of this project was to determine what the substitute teacher onboarding process was, including employment requirements and required training, for substitute teachers in the Matanuska-Susitna Borough School District and to make recommendations to the district for the training of substitute teachers. Substitute teachers in the district were asked to complete a survey regarding their experience, current level of training, and perceived training needs. I found that regardless of the amount of experience and training substitute teachers already possess, they want more training not only in the programs and initiatives utilized by the district, but also in effective instructional strategies, best practices, and teaching methods in curricular areas. While the district onboarding process is fairly comprehensive, as is the available optional training, I developed recommendations to improve the onboarding process and training options for substitute teachers in the district to strengthen substitute teacher effectiveness.