Recent Submissions

  • Exploring variability in the diet of depredating sperm whales in the Gulf of Alaska through stable isotope analysis

    Wild, Lauren A.; Mueter, Franz; Witteveen, Briana H.; Straley, Janice M. (The Royal Society Publishing, 2020-01-27)
    Sperm whales interact with commercially important groundfish fisheries offshore in the Gulf of Alaska (GOA). This study aims to use stable isotope analysis to better understand the trophic variability of sperm whales and their potential prey, and to use dietary mixing models to estimate the importance of prey species to sperm whale diets. We analysed tissue samples from sperm whales and seven potential prey (five groundfish and two squid species). Samples were analysed for stable carbon and nitrogen isotope ratios, and diet composition was estimated using Bayesian isotopic mixing models. Mixing model results suggest that an isotopically combined sablefish/ dogfish group, skates and rockfish make up the largest proportion of sperm whale diets (35%, 28% and 12%) in the GOA. The top prey items of whales that interact more frequently with fishing vessels consisted of skates (49%) and the sablefish/dogfish group (24%). This is the first known study to provide an isotopic baseline of adult male sperm whales and these adult groundfish and offshore squid species, and to assign contributions of prey to whale diets in the GOA. This study provides information to commercial fishermen and fisheries managers to better understand trophic connections of important commercial species.
  • Humpback whales feed on hatchery-released juvenile salmon

    Chenoweth, Ellen M.; Straley, Janice M.; McPhee, Megan V.; Atkinson, Shannon; Reifenstuhl, Steve (The Royal Society Publishing, 2017-06-07)
    Humpback whales are remarkable for the behavioural plasticity of their feeding tactics and the diversity of their diets. Within the last decade at hatchery release sites in Southeast Alaska, humpback whales have begun exploiting juvenile salmon, a previously undocumented prey. The anthropogenic source of these salmon and their important contribution to local fisheries makes the emergence of humpback whale predation a concern for the Southeast Alaska economy. Here, we describe the frequency of observing humpback whales, examine the role of temporal and spatial variables affecting the probability of sighting humpback whales and describe prey capture behaviours at five hatchery release sites. We coordinated twice daily 15 min observations during the spring release seasons 2010–2015. Using logistic regression, we determined that the probability of occurrence of humpback whales increased after releases began and decreased after releases concluded. The probability of whale occurrence varied among release sites but did not increase significantly over the 6 year study period. Whales were reported to be feeding on juvenile chum, Chinook and coho salmon, with photographic and video records of whales feeding on coho salmon. The ability to adapt to new prey sources may be key to sustaining their population in a changing ocean.
  • Summit: The UAS Writing Center's Collection of Exceptional Academic Works for 2020/2021

    Billings, Rayne; Brend, Olive; Goodman, Jessy; Cruz, Celestina; Erickson, Anastasia; Hein, Berni; Hoagland, James; File, Braden; Steiner, Alicia; File, Braden; et al. (University of Alaska Southeast Writing Center, 2021)
    We at the UAS Writing Center are once again pleased to announce the completion of the second edition of our undergraduate academic writing journal, Summit: The UAS Writing Center’s Collection of Exceptional Academic Works for 2020/2021. This year’s edition is dedicated to Allison Neeland, our past Specialist, for all her support and dedication to the Writing Center. We also extend a hearty congratulation to UAS senior Celestina Cruz for winning the 2020/2021 Ernestine Hayes Award for Excellence in Academic Writing. Also included in the journal are the works of five other student writers: Rayne Billings, Anastasia Erickson, Berni Hein, James Hoagland, and Alicia Steiner. Thank you to everyone who submitted, to our panel of faculty and student judges, to Diersen Bankert for creating this year’s stunning cover, to Student Government for funding the prize money, and to everyone else who has supported this publication.
  • Pectoral herding: an innovative tactic for humpback whale foraging

    Kosma, Madison, M.; Werth, Alexander J.; Szabo, Andrew R.; Straley, Janice M. (The Royal Society, 2019-09-23)
    Humpback whales (Megaptera novaeangliae) have exceptionally long pectorals (i.e. flippers) that aid in shallow water navigation, rapid acceleration and increased manoeuvrability. The use of pectorals to herd or manipulate prey has been hypothesized since the 1930s. We combined new technology and a unique viewing platform to document the additional use of pectorals to aggregate prey during foraging events. Here, we provide a description of ‘pectoral herding’ and explore the conditions that may promote this innovative foraging behaviour. Specifically, we analysed aerial videos and photographic sequences to assess the function of pectorals during feeding events near salmon hatchery release sites in Southeast Alaska (2016–2018). We observed the use of solo bubble-nets to initially corral prey, followed by calculated movements to establish a secondary boundary with the pectorals—further condensing prey and increasing foraging efficiency. We found three ways in which humpback whales use pectorals to herd prey: (i) create a physical barrier to prevent evasion, (ii) cause water motion to guide prey towards the mouth, and (iii) position the ventral side to reflect light and alter prey movement. Our findings suggest that behavioural plasticity may aid foraging in changing environments and shifts in prey availability. Further study would clarify if ‘pectoral herding’ is used as a principal foraging tool by the broader humpback whale population and the conditions that promote its use.
  • 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.
  • 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.
  • Recycling Attitudes and Behavior among a Clinic-Based Sample of Low-Income Hispanic Women in Southeast Texas

    Pearson, Heidi C.; Dawson, Lauren, N.; Breitkopf, Carmen Radecki (2012-04-06)
    We examined attitudes and behavior surrounding voluntary recycling in a population of low-income Hispanic women. Participants (N = 1,512) 18–55 years of age completed a self-report survey and responded to questions regarding household recycling behavior, recycling knowledge, recycling beliefs, potential barriers to recycling (transportation mode, time), acculturation, demographic characteristics (age, income, employment, marital status, education, number of children, birth country), and social desirability. Forty-six percent of participants (n = 810) indicated that they or someone else in their household recycled. In a logistic regression model controlling for social desirability, recycling behavior was related to increased age (P,0.05), lower acculturation (P,0.01), knowing what to recycle (P,0.01), knowing that recycling saves landfill space (P,0.05), and disagreeing that recycling takes too much time (P,0.001). A Sobel test revealed that acculturation mediated the relationship between recycling knowledge and recycling behavior (P,0.05). We offer new information on recycling behavior among Hispanic women and highlight the need for educational outreach and intervention strategies to increase recycling behavior within this understudied population.
  • CONSERVATION BENEFITS OF WHALE WATCHING IN JUNEAU, ALASKA

    Schuler, Alicia, R.; Pearson, Heidi C. (Cognizant, LLC, 2020-01-03)
    An increasing number of visitors to Juneau, AK, alongside a predictable population of humpback whales (Megaptera novaeangliae), has supported the substantial growth of its whale-watching indus- try. The industry provides benefits to the community through economic gains, while the experi- ence can foster environmental awareness and support for protection of whales and the environment. However, the sustainability of the industry could be jeopardized if increasing whale-watching vessel pressure affects the health of its resource, the whales. This study investigates whether participation in whale-watching tours in Juneau, AK can support conservation of whales and the environment. Participant knowledge, attitudes, intentions, and behaviors were obtained from 2,331 respondents in surveys before, after, and 6 months after a whale-watching tour during the 2016 and 2017 seasons. Following a whale watch, the percentage of participants that indicated whale watching as a knowl- edge source increased (p = 0.022), awareness of guidelines and regulations doubled (p < 0.001), and strong support for regulations increased (p = 0.016). Six months later, these responses remained significantly higher than before the whale watch. Despite knowledge of distance threshold increasing after a whale watch (p = 0.003) and 6 months after (p = 0.021), getting close to whales remained an important factor in a participant’s whale watch. Participants had a higher likelihood of strongly sup- porting guidelines and regulations if they indicated that boats can have a negative impact on whales or were aware of guidelines and regulations. Lastly, participants that acknowledged negative effects on whales from boats had higher overall proenvironmental attitudes. This study indicates that incor- porating messages that facilitate participant awareness of guidelines/regulations and the purpose of those measures can support conservation and protection of local whale populations through manag- ing participant expectations and ultimately encouraging operator compliance.
  • Humpback Whale Movements and Behavior in Response to Whale-Watching Vessels in Juneau, AK

    Schuler, Alicia, R.; Piwetz, Sarah; Clemente, Jacopo Di; Steckler, David; Mueter, Franz; Pearson, Heidi C. (2019-11-20)
    The whale-watching industry in Juneau, Alaska relies primarily on the presence of North Pacific humpback whales (Megaptera novaeangliae). To meet demands from the rapidly growing tourism industry, the number of whale-watching vessels in this region has tripled over the last 18 years. As a result, increased vessel presence could have negative effects on humpback whales, ranging from short-term behavioral disturbance to long-term impacts. The current humpback whale viewing regulations are outdated and may not be as effective as they were 18 years ago, when both the whale-watching industry and humpback whale population were smaller. The present study assessed how humpback whale movement and behavioral patterns were affected by (1) vessel presence and number of vessels present, and (2) time spent in the presence of vessels. The study also determined how humpback whale behavioral state transitions were affected by vessel presence. A total of 201 humpback whale focal follows were conducted during summer 2016 and 2017. Based on linear mixed effects models, whales in the presence (vs. absence) of vessels exhibited 38.9% higher deviation in linear movement (p = 0.001), 6.2% increase in swimming speed (p = 0.047) and a 6.7% decrease in inter-breath intervals (IBI) (p = 0.025). For each additional vessel present, deviation increased by 6.2% (p = 0.022) and IBI decreased by 3.4% (p = 0.001). As time spent in the presence of vessels increased, respiration rate increased (p = 0.011). Feeding and traveling humpback whales were likely to maintain their behavioral state regardless of vessel presence, while surface active humpback whales were likely to transition to traveling in the presence of vessels. These short-term changes in movement and behavior in response to whale-watching vessels could lead to cumulative, long-term consequences, negatively impacting the health and predictability of the resource on which the industry relies. Current formal vessel approach regulations and voluntary guidelines should be revisited to reduce vessel pressure and mitigate potential negative effects of this growing whale-watching industry.
  • Oceanographic Determinants of the Abundance of Common Dolphins (Delphinus delphis) in the South of Portugal.

    Castro, J.; Couto, A.; Borges, F. O.; Laborde, M. I.; Pearson, H. C.; Rosa, R.; Cid, A.; Pearson, Heidi C. (MDPI, 2020-08)
    Off mainland Portugal, the common dolphin (Delphinus delphis) is the most sighted cetacean, although information on this species is limited. The Atlantic coast of Southern Portugal is characterized by an intense wind-driven upwelling, creating ideal conditions for common dolphins. Using data collected aboard whale-watching boats (1929 sightings and 4548 h effort during 2010–2014), this study aims to understand the relationships between abundance rates (AR) of dolphins of different age classes (adults, juveniles, calves and newborns) and oceanographic [chlorophyll a (Chl-a) and sea surface temperature (SST)] variables. Over 70% of the groups contained immature animals. The AR of adults was negatively related with Chl-a, but not related to SST values. The AR of juveniles was positively related with SST. For calves and newborns, although the relationship between SST and AR is similar to that observed for juveniles, the effect could not be distinguished from zero. There was no relationship between Chl-a levels and the AR of juveniles, calves and newborns. These results corroborate previous findings that common dolphins tend to occur in highly productive areas demonstrating linkages between their abundance and oceanographic variables, and that this region may be a potential nursery ground.
  • Morainal Bank Evolution and Impact on Terminus Dynamics During a Tidewater Glacier Stillstand

    Eidam, E. F.; Sutherland, D. A.; Duncan, D.; Kienholz, Christian; Amundson, Jason M.; Motyka, R. J. (American Geophysical Union, 2020-09-25)
    Sedimentary processes are known to help facilitate tidewater glacier advance, but their role in modulating retreat is uncertain and poorly quantified. In this study we use repeated seafloor bathymetric surveys and satellite‐derived terminus positions from LeConte Glacier, Alaska, to evaluate the evolution of a morainal bank and related changes in terminus dynamics over a 17‐year period. The glacier experienced a rapid retreat between 1994 and 1999, before stabilizing at a constriction in the fjord. Since then, the glacier terminus has remained stabilized while constructing a morainal bank up to 140 m high in water depths of 240–260 m, with rates of sediment delivery of 3.3 Å~ 105 to 3.8 Å~ 105 m3 a−1. Based on repeated interannual surveys between 2016 and 2018, the moraine is a dynamic feature characterized by push ridges, evidence of active gravity flows, and bulldozing by the glacier at rates of up to meters per day. Beginning in 2016, the summertime terminus has become increasingly retracted, revealing a newly emerging basin potentially signaling the onset of renewed retreat. Between 2000 and 2016, the growing moraine reduced the exposed submarine area of the terminus by up to 22%, altered the geometry of the terminus during seasonal advances, and altered the terminus stress balance. These feedbacks for calving, melting, and ice flow likely represent mechanisms whereby moraine growth may delay glacier retreat, in a system where readvance is unlikely.
  • Summit: The UAS Writing Center's Collection of Exceptional Academic Works for 2019/2020

    Neeland, Allison; Zahnd, Honesty; Steiner, Alicia; Cruz, Celestina; Cole, Robert; Billings, Rayne; Brend, Olive (The University of Alaska Southeast Writing Center, 2020)
    It is with great enthusiasm that the UAS Writing Center launches our inaugural edition of Summit: The UAS Writing Center’s Collection of Exceptional Academic Works for 2019/2020. In the Writing Center, we have the privilege of seeing the wide range of talents and interests of our UAS students and the exceptional way that they communicate their research, analysis, and philosophical ruminations through essays, speeches, and written reports. The tutors in the Writing Center engage with their peers in fascinating discussions of historical events, political debates, scientific discoveries, teaching pedagogy, and business theory (to name a few). We celebrate when students receive stellar grades on their assignments, but we also recognize that good writing should be shared beyond the classroom. Summit emerged from a desire to highlight and publish the extraordinary writing that we get the honor to see in the Writing Center every day. This journal, however, is more than just a showcase of undergraduate writing. It has also been an opportunity for the undergraduate student tutors to engage in a collaborative project that required time management, careful communication, attention to detail and leadership skills. The editors and contributors have persevered through unimaginable (until now) challenges including unprecedented budget cuts at the university and a global pandemic that forced us to move our work online. At a time when the present feels chaotic and worrying, the undergraduate students at UAS remind me that our future is in good hands. I am confident in our new generation of leaders as I’ve watched our students think critically, engage in the community, and work tirelessly for projects they believe in. It is joy to present our first edition of Summit! Allison Neeland UAS Writing Center Specialist
  • Formation, flow and break-up of ephemeral ice mélange at LeConte Glacier and Bay, Alaska.

    Amundson, Jason M.; Kienholz, Christian; Hager, Alexander O.; Jackson, Rebecca H.; Motyka, Roman J.; Nash, Jonathan D.; Sutherland, David A. (Cambridge University Press, 2020-05-14)
    Ice mélange has been postulated to impact glacier and fjord dynamics through a variety of mechanical and thermodynamic couplings. However, observations of these interactions are very limited. Here, we report on glaciological and oceanographic data that were collected from 2016 to 2017 at LeConte Glacier and Bay, Alaska, and serendipitously captured the formation, flow and break-up of ephemeral ice mélange. Sea ice formed overnight in mid-February. Over the subsequent week, the sea ice and icebergs were compacted by the advancing glacier terminus, after which the ice mélange flowed quasi-statically. The presence of ice mélange coincided with the lowest glacier velocities and frontal ablation rates in our record. In early April, increasing glacier runoff and the formation of a sub-ice-mélange plume began to melt and pull apart the ice mélange. The plume, outgoing tides and large calving events contributed to its break-up, which took place over a week and occurred in pulses. Unlike observations from elsewhere, the loss of ice mélange integrity did not coincide with the onset of seasonal glacier retreat. Our observations provide a challenge to ice mélange models aimed at quantifying the mechanical and thermodynamic couplings between ice mélange, glaciers and fjords.
  • Deglacierization of a marginal basin and implications for outburst floods

    Kienholz, Christian; Pierce, Jamie; Hood, Eran; Amundson, Jason M.; Wolken, Gabriel; Jacobs, Aaron; Hart, Skye; Jones, Katreen Wikstrom; Abdel-Fattah, Dina; Johnson, Crane; et al. (Frontiers in Earth Science, 2020-05-27)
    Suicide Basin is a partly glacierized marginal basin of Mendenhall Glacier, Alaska, that has released glacier lake outburst floods (GLOFs) annually since 2011. The floods cause inundation and erosion in the Mendenhall Valley, impacting homes and other infrastructure. Here, we utilize in-situ and remote sensing data to assess the recent evolution and current state of Suicide Basin. We focus on the 2018 and 2019 melt seasons, during which we collected most of our data, partly using unmanned aerial vehicles (UAVs). To provide longer-term context, we analyze DEMs collected since 2006 and model glacier surface mass balance over the 2006–2019 period. During the 2018 and 2019 outburst flood events, Suicide Basin released ∼ 30 Å~ 106 m3 of water within approximately 4–5 days. Since lake drainage was partial in both years, these ∼ 30 Å~ 106 m3 represent only a fraction (∼ 60%) of the basin’s total storage capacity. In contrast to previous years, subglacial drainage was preceded by supraglacial outflow over the ice dam, which lasted ∼ 1 day in 2018 and 6 days in 2019. Two large calving events occurred in 2018 and 2019, with submerged ice breaking off the main glacier during lake filling, thereby increasing the basin’s storage capacity. In 2018, the floating ice in the basin was 36 m thick on average. In 2019, ice thickness was 29 m, suggesting rapid decay of the ice tongue despite increasing ice inflow from Mendenhall Glacier. The ice dam at the basin entrance thinned by more than 5 m a–1 from 2018 to 2019, which is approximately double the rate of the reference period 2006–2018. While ice-dam thinning reduces water storage capacity in the basin, that capacity is increased by declining ice volume in the basin and longitudinal lake expansion, with the latter process challenging to predict. The potential for premature drainage onset (i.e., drainage before the lake’s storage capacity is reached), intermittent drainage decelerations, and early drainage termination further complicates prediction of future GLOF events.
  • MABEL photon-counting laser altimetry data in Alaska for ICESat-2 simulations and development

    Brunt, Kelly M.; Neumann, Thomas A.; Amundson, Jason M.; Kavanaugh, Jeffrey L.; Moussavi, Mahsa S.; Walsh, Kaitlin M.; Cook, William B.; Markus, Thorsten (Copernicus Publications on behalf of the European Geosciences Union, 2016-08-10)
    Ice, Cloud, and land Elevation Satellite-2 (ICESat-2) is scheduled to launch in late 2017 and will carry the Advanced Topographic Laser Altimeter System (ATLAS) which is a photon-counting laser altimeter and represents a new approach to satellite determination of surface elevation. Given the new technology of ATLAS, an airborne instrument, the Multiple Altimeter Beam Experimental Lidar (MABEL), was developed to provide data needed for satellite-algorithm development and ICESat-2 error analysis. MABEL was deployed out of Fairbanks, Alaska, in July 2014 to provide a test dataset for algorithm development in summer conditions with water-saturated snow and ice surfaces. Here we compare MABEL lidar data to in situ observations in Southeast Alaska to assess instrument performance in summer conditions and in the presence of glacier surface melt ponds and a wet snowpack. Results indicate the following: (1) based on MABEL and in situ data comparisons, the ATLAS 90m beam-spacing strategy will provide a valid assessment of across-track slope that is consistent with shallow slopes (< 1) of an ice-sheet interior over 50 to 150m length scales; (2) the dense along-track sampling strategy of photon counting systems can provide crevasse detail; and (3) MABEL 532 nm wavelength light may sample both the surface and subsurface of shallow (approximately 2m deep) supraglacial melt ponds. The data associated with crevasses and melt ponds indicate the potential ICESat-2 will have for the study of mountain and other small glaciers.

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