M.S. - Natural Resources and Environmental Management

Permanent URI for this collectionhttps://hdl.handle.net/10125/8828

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Wild ungulate impacts on ranchlands and across managed landscapes in the Hawaiian islands
(University of Hawai'i at Manoa, 2025) Katayama, Lauren; Price, Melissa R.; Natural Resources and Environmental Management
Invasive wild ungulates pose significant ecological and economic challenges worldwide, particularly in island ecosystems where the absence of large predators exacerbates their impacts. Across the Hawaiian Islands, wild ungulates such as axis deer (Axis axis), mouflon sheep (Ovis musimon), feral goats (Capra hircus), and wild pigs (Sus scrofa) contribute to overgrazing, habitat degradation, and impacts to agricultural production. While their effects on native ecosystems are well-documented, less is known about their influence on forage availability in ranchlands and how their distribution aligns with land management designations. This thesis examined the relationship between wild ungulate abundance, forage availability, and land-use classifications across the Hawaiian Islands. We investigated how wild ungulate presence affects forage loss and plant community composition using game cameras, exclusion cages, and vegetation surveys. Results indicate that while elevation is the primary driver of forage availability, wild ungulate detections were associated with reduced vegetation biomass at many sites, consistent with rancher concerns regarding overgrazing by wild ungulates. We analyzed predicted wild ungulate abundance across Priority Conservation Areas, Priority Hunting Areas, and Other Areas. Findings suggested that on the islands of Hawaiʻi and Maui, wild pigs and mouflon sheep are more abundant in conservation lands, while axis deer are more prevalent in agricultural and private lands, highlighting key areas for management intervention. These findings provide insights into the ecological impacts of wild ungulates on ranchlands and conservation areas, emphasizing the need for targeted, landscape-scale management strategies for invasive wild ungulates that achieve biodiversity conservation and sustainable agriculture goals.
Community Resilience to Climate Change-Induced Disasters in Northern Kaua'i: Perspectives following the April 2018 Floods
(University of Hawai'i at Manoa, 2024) Luebbe, Kristine Kilikina Marie; Vaughan, Mehana; Natural Resources and Environmental Management
As climate change-induced hazards increase risk of dloods, landslides, dires and other disasters, many communities are struggling with how to build resilience in the face of climate change. Even with a growing emphasis on resilience in academic and planning spheres, there remain questions regarding what resilience means, who directs resilience efforts, who benedits, and who is left out. Despite the increase in resilience plans, policies and resources, there is limited understanding of communitiesʻcollective experiences with, and conceptualizations of, resilience. In April 2018 the island of Kaua‘i received 50 inches of rain in approximately 24 hours causing dlooding across the island. Landslides closed the only highway traveled by over a million tourists annually and isolated several coastal communities in northern Kaua‘i for almost a year. These events and their aftermath forced island residents and policy makers to evaluate effective resilience building measures. Do efforts to increase resilience at the state, county, and community levels align with perceptions and values of resilience articulated by the community after the 2018 dloods? What do community perceptions and values teach us about expanding and operationalizing the concept of resilience? This research sought to determine community perceptions and values in resilience through 80 in depth interviews conducted after the dloods. Then, I performed a content analysis of community, county, and state plans and initiatives to determine both explicit dedinitions as well as implicit conceptualizations of resilience. Comparing how resilience is conceptualized and operationalized in management plans with community perceptions and values revealed challenges and barriers to operationalizing resilience as well as areas where further collaboration is needed to effectively plan for social-ecological resilience in the face of climate change. Key elements of resilience following the 2018 Kauaʻi dloods include the importance of community cohesion which may be threatened by tourism and demographic changes along with care and connection to the environment. Place based plans designed through participatory processes are most effective at conceptualizing resilience from a social-ecological perspective. This was evident in the The Hā ʻena to Hanalei Community Resilience Plan, where the resilient recovery plan provided a comprehensive way to operationalize social-ecological resilience through action planning rooted in transformation and learning cycles, rather than technological dixes for bouncing back. Overall, operationalizing social-ecological resilience can be more effective when utilized as a cohesive strategy across all phases of disaster management and planning under a framework of adaptive governance.
The Future of Agricultural Land Suitability in Hawaiʻi: GIS Analysis of Coffee & Taro
(University of Hawai'i at Manoa, 2024) Teper, Aaron Mark Blum; Miura, Tomoaki; Natural Resources and Environmental Management
Climate change is a concerning phenomenon, especially when it comes to the diverse impacts it has on agriculture and crop production. This study employed geographic information system (GIS)-based suitability modeling to assess the impact of future temperature and rainfall conditions on the suitability of growing coffee, and dryland taro. The crops were selected based on economic viability, cultural significance, and historical growth success in Hawaiʻi. The optimum crop growth conditions (i.e., climate, soil, and topographic conditions) were determined by integrating industry experts’ and farmers' insights and knowledge into the data collection process. These growth conditions were then spatially extrapolated to the main Hawaiian Islands through GIS. Future climate data were obtained from WorldClim and downscaled to Hawaiʻi, including the 12 most recent global climate models available (Coupled Model Intercomparison Project Phase 6, CMIP6) across two shared socioeconomic pathways (SSP 245 and 585) spanning the years 2021-2080 in 20-year intervals. SSP 245 and 585 are two different climate futures based on economic and social development and the related greenhouse gas (GHG) emissions. The 12 models and two pathways were used to account for the varying results of future climate models. Results for coffee suggest positive trends for the crop to remain viable on current farmlands over the next 60 years with gradual climate change. Land suitability analysis on dryland taro revealed a steady increase across agricultural land, with the potential to become a staple crop for local food production. Overall, farming in Hawaiʻi must continue to ramp up despite climate change to meet local demand and reduce dependence on import goods.
CHARACTERIZING PATTERNS AND IDENTIFYING PREDICTION MODELS TO SIMULATE SOIL MOISTURE
(University of Hawai'i at Manoa, 2024) Heu, Cherryle Noelani; Tsang, Yinphan; Natural Resources and Environmental Management
Soil moisture is known to be a critical component in our Earth’s system and serves a pivotal role in evaluating water balance. Its dynamic behavior is essential for understanding hydrological processes and water budgets. Despite its significance, there is still much to learn about the key drivers of soil moisture dynamics and the variables that influence these patterns. This study analyzed hourly soil moisture data from 16 sites in Canterbury, New Zealand, to identify wetting and drying events over a period of three to five years. To characterize the dynamic behavior of soil moisture during each event, the study proposed five distinct sets of soil moisture signatures. For each signature, statistical analyses such as Principal Component Analysis (PCA) and Pearson Correlation were conducted to find what antecedent or climate variables could statistically explain a signature’s value or variability. After extensive examination, no significant drivers were found. Additionally, this study used a machine learning technique, Long Short-term Memory (LSTM) to generate 12-hour to 72-hour soil moisture predictions for depths 10, 40, and 80cm. When comparing its performance to that of Autoregressive Integrated Moving Average (ARIMA), ARIMA was found to perform better overall, with the advantages of easy hyperparameter tuning. However, the LSTM models demonstrated a unique ability to predict soil moisture at sites not included in the model’s training dataset and were most successful in predicting soil moisture when the model was trained from multiple sites’ datasets. Both LSTM and ARIMA faced limitations, particularly a tendency for predictions to lag behind observed values. The simplicity and adaptability of ARIMA make it well-suited for site-specific applications, while LSTM's strong performance with cumulative data indicates its potential for broader applications, such as regions with limited historical soil moisture data. Further refinement and development of LSTM models could enhance their applicability and accuracy, providing greater potential for more robust soil moisture predictions.
TEMPERATURE ENHANCES SWIMMING PERFORMANCE OF INVASIVE SPECIES IN HAWAIIAN STREAMS
(University of Hawai'i at Manoa, 2024) Engel, Leigh Ashley; Tsang, YinPhan; Grabowski, Timothy; Natural Resources and Environmental Management
The effects of climate change, urbanization, and hydrologic modifications on native stream fishes have been well documented; however, the impacts of their effects on invasive species are not as well understood. In the relatively short, high-gradient, and flashy streams of the Hawaiian Islands, continued changes in flow regimes, particularly increased frequency and intensity of floods, and temperature may interact with the swimming performance of invasive species to affect their distribution and abundance patterns within watersheds. Therefore, the objective of this study was to assess the swimming performance of three of the most common invasive species in Hawai‘i: hybridized Molly (Poecilia mexicana X P. formosa X P. sphenops), Green Swordtail (Xiphophorus hellerii), and Blackchin Tilapia (Sarotherodon melanotheron); at three temperature treatments. Individuals were placed in a 10-L recirculating flow tank and subjected to increasing water velocities to measure Uburst and Ucrit at three temperature treatments, 20.0, 26.0, and 32.0°C. Regardless of species, both Uburst and Ucrit increased with increasing temperature suggesting that warming stream temperatures may allow the tested species to establish and maintain populations in higher gradient portions of Hawaiian watersheds despite predicted increases in extreme flow events. Further, inter- and intraspecific differences in morphology, such as body depth, and behavior influenced swimming performance. These critical swimming speeds of non-native fish species will be important factors to model the potential spread and persistence of populations within Hawaiian watersheds, particularly as environmental conditions continue to change due to climate alterations, and allow for a better assessment of control and eradication strategies.
How disturbing: humans are intertwined with ecosystem health. A study of the effects of human disturbance on soil health, aboveground biomass, and species community makeup in tropical and subtropical systems
(University of Hawai'i at Manoa, 2024) Estrada, Kristina Nicole; Crow, Susan E.; Maaz, Tai M.; Natural Resources and Environmental Management
Anthropogenic, or human, disturbances have shaped the way the natural world functions for thousands of years. Today, climate is changing faster than ever before, global biodiversity is declining at an alarming rate, and our natural resources are depleting. While we still need to feed the growing population, we also need to conserve and restore the land to coexist with all other species. Is there an achievable balance between both of these objectives? Here I tested a community ecology concept, applying the intermediate disturbance hypothesis (IDH) to understand how soil health, tree and shrub community makeup and aboveground biomass shifted with anthropogenic disturbance across land use types. I measured the level of anthropogenic disturbance within each land use type to better understand how our actions differ across thelandscape and affect these outcomes. I developed an anthropogenic disturbance index that could be applied to the land use types at our study sites including Maui, Hawaiʻi, Puerto Rico, and Pohnpei, Federated States of Micronesia. I first identified indicators of disturbance in categories of geomorphology, biota, hydrology, atmosphere, and culture. We used questionnaires, field measurements, and online GIS databases to determine Anthropogenic Disturbance Index (ADI) scores for each. Next, I ranked and compared disturbance levels within each land use and across all sites on a continuous scale, rather than categorizing each land use as a specific disturbance level. Disturbance levels were dependent on land use type (p<.001); however, ADI scores overlapped between them. We found that the IDH did not apply to our sites but that there was instead a threshold of ADI scores from 35-55% where soil health scores dramatically decreased overall. While biomass did not have any significant factors found to influence amounts, species richness and diversity changed with ADI scores. We may use this to advise land managers to incorporate low disturbance conservation practices such as the addition of perennials in their systems. Our disturbance practices may not only establish resiliency and safeguard the soil and plants we work with from the effects of climate change but also the ecosystem services soil health can support, such as nutrient cycling and carbon sequestration.
NEST SITE SELECTION AND PREDATOR IMPACTS ON THE REPRODUCTIVE SUCCESS OF THREE ENDANGERED WATERBIRDS IN HAWAIʻI.
(University of Hawai'i at Manoa, 2024) Botet Rodriguez, Jaime Andres; Price, Melissa R.; Natural Resources and Environmental Management
Precocial species leave the nest soon after hatching, making them vulnerable to a variety of threats as they search for food and shelter prior to gaining the ability to fly. Adaptive habitat-selection theory suggests that animals should select areas with habitat characteristics that maximize fitness, so species with precocial chicks should select nesting areas with characteristics that maximize success during both the egg and chick stages. Recent studies suggest that endangered species recovery may be hampered when predator impacts differ between nest and chick stages, requiring different management strategies to protect across the reproductive stages. Predation of the egg and chick stages are a major cause of reproductive failure in three endangered Hawaiian waterbirds, the Ae‘o (Hawaiian Stilt; Himantopus mexicanus knudseni), the ‘Alae ke‘oke‘o (Hawaiian Coot), and ‘Alae ‘ula (Hawaiian Gallinule; Gallinula galeata sandvicensis), but predator types likely differ between stages, making them an ideal species in which to examine relationships between nest-site selection, predator types, nesting and fledging success. In this study, we utilized motion-activated game cameras at nests and tracking of chicks to evaluate: (1) which nest-site characteristics are related to egg predation by different species; and (2) the relationship between habitat characteristics, predator detections at the nest, and fledging success. (3) which nest-site characteristics and predator detections at nest are related to chick survival by different species; and (4) what is the relationship between predator detections and nest site characteristics with chick fate by the two Hawaiian waterbird species. Using a linear and binomial logistic regression and exposure models, we found that nest concealment of vegetation (vegetation density) was not a predictor for predation risk at both the nest and chick stages. We found a 5% increase in stilt chick survival over the nesting season and a 5% decrease in gallinule chick survival over the nesting season, suggesting seasonal changes in food abundance or predation risk. ‘Alae ‘ula chicks were detected in American Bullfrog stomachs, confirming them as a source of chick, but not egg, mortality. Based on our results, management actions aimed at improving nesting success will not simultaneously improve chick survival, with the exception of the removal of mammals, which benefits both. A critical need to improve outcomes for chicks is the development of better control options for invasive reptiles, amphibians, and invertebrates.
INDIGENOUS KNOWLEDGE AND FACTORS INFLUENCING DETECTABILITY OF PUEO (HAWAIIAN SHORT-EARED OWL, ASIO FLAMMEUS SANDWICHENSIS)
(University of Hawai'i at Manoa, 2023) Stormcrow, Kaleiheana-a-Pōhaku; Price, Melissa R.; Natural Resources and Environmental Management
Apex predators such as raptors play important roles in ecosystem regulation. In addition to these important roles and the charismatic nature of apex predators, apex predators often have a mirrored cultural significance for Indigenous Peoples. When their symbolic and spiritual value is so great that it affects that culture’s relationship and adaptation to the environment, they are considered Cultural Keystone Species (CKS). In addition to supporting ecosystem complexity, these species support cultural complexity regarding social identity, cultural practices, and beliefs. Pueo are the only remaining native raptor that breed across the Hawaiian archipelago, and as such play key ecological and cultural roles. In this thesis research I aimed to: (1) highlight the breadth of Indigenous Knowledge of Pueo documented in Hawaiian language newspapers and (2) identify factors influencing Pueo detectability on Hawaiʻi Island. Pueo have relationships with multiple akua (elemental forces) who play vital roles in ecosystem functionality and nutrient cycling, and have relationships with 35 species across articles, indicating our kūpuna (ancestors) understood the system stability that Pueo supported, and the functionality of the pilina (relationship) that Kānaka (Native Hawaiians) have with Pueo. Results from field surveys demonstrate that Pueo utilize every available terrestrial habitat type in Hawaiʻi, but their occupancy and detection probability are constrained by elevation and temperature respectively. On Hawaiʻi island, where Pueo co-occur with ʻIo (Buteo solitarius), we observed a potential temporal shift in their behavior. Together, the results of these chapters support the notion that Pueo are a Cultural Keystone Species and a generalist apex predator with critical cultural and ecological functions.
Climate, mineralogy, and depth control soil organic matter composition and soil carbon storage in Hawaiian tropical montane wet forests
(University of Hawai'i at Manoa, 2023) Tayo, Malissa Ann Gueco; Litton, Creighton M.; Giardina, Christian P.; Natural Resources and Environmental Management
The formation and stabilization of soil carbon (C) in tropical forests are key processes influencing the global C cycle. Both climate and mineralogy are known to exert important control over these processes, especially at depth in tropical soils. However, recent work suggests plant litter quality-controlled microbial assimilation also plays an important role in the stabilization of soil C. The Microbial Efficiency Matrix Stabilization (MEMS) framework describes the formation and stabilization of soil organic matter (SOM) by identifying significant C pools within soil and linking those pools to plant quality input pools. The MEMS framework, however, fails to incorporate important emerging concepts such as mineralogical content. In this study, I utilized a highly constrained (constant vegetation, geology/substrate/soils, soil moisture, and disturbance history), long-term, whole-ecosystem mean annual temperature (MAT) gradient spanning 4.3°C located in Hawaiian tropical montane wet forests to evaluate the controls on soil C storage and formation. To do this, I measured above- and belowground plant litter quality pools, and SOM composition, mineralogy, and age to 1 m depth across this MAT gradient. Overall, the data presented here show varying support of the tested hypothesis that all examined controls collectively control complex SOM C dynamics and storage in tropical montane wet forests. Multi-model averaging revealed that the combination of MAT, depth, and mineralogy best explain changes in SOM C pool composition and age. Specifically, these variables explained 82% of the variation in SOM composition for light-particulate organic matter (LPOM), 40% for heavy-POM (HPOM), and 56% for mineral-associated OM (MAOM). Specifically, the primary mineral displaying most control over the C stock of the LPOM, HPOM, and MAOM, respectively, was poorly- and non-crystalline minerals (PNCM), crystalline iron (Fe) and organo-aluminum. With increasing MAT, LPOM C declined in the surface soils. Deeper within the soil profile, MAOM C, a critical component of longer-term soil C storage, decreased. However, an inverse relationship was observed for HPOM C indicating transitions of mineral control from PNCM to crystalline Fe. This highlight HPOM fraction as a primary control on stable SOM storage with increasing MAT and depth in mineral rich tropical ecosystems. All of these result together support the need to create a new modeling framework (e.g., in MEMS) to account for the formation of mineral rich tropical SOM that includes: the impact of changes in MAT on mineralogy; linking plant quality to surface soils and mineralogy to deep SOM formation; quantifying all important SOM fractions to depth and, importantly, separating LPOM and HPOM; utilizing new data analysis methods that model all of these important factors (i.e., climate, plant quality and quantity, mineralogy, depth).
Current And Future Climate Models For Ten Remaining Species Of Achatinella To Inform Potential Locations Of Ex Situ Predator-free Exclosures
(University of Hawaii at Manoa, 2023) Kitamura, Philip Kei; Price, Melissa R.; Natural Resources and Environmental Management
Ectotherms are particularly sensitive to drought and extreme temperatures and may act as bellwethers of climate change, but declines are often attributed to other threats. As a result, the threat of climate change may be under-estimated. The decline of Hawaiian tree snails in the genus Achatinella has largely been attributed to over-collection, habitat loss, and introduced predators. Currently, most species remain only in captive rearing facilities or predator-free exclosures, following recent sharp declines and population “blink-outs”. In this study, I developed species distribution models for the ten remaining species in the genus Achatinella under present and future climate scenarios, within the historical range on O‘ahu, as well as areas outside the historical range across the Hawaiian Islands. I found that ~98% of suitable area across the Hawaiian Islands is outside of the historical range. Additionally, most of the climate-suitable habitat under future conditions on O‘ahu do not overlap with areas where populations are currently persisting, suggesting that without translocation, these species may become extinct sometime before the end of the century. Our results raise alarms regarding the likely impacts of climate change on wildlife long before the end of the century and highlight the importance of translocations outside the historical range for the persistence of climate-sensitive species.
Aeʻo (Hawaiian Stilt, Himantopus mexicanus knudensi) Reproduction and Survival
(University of Hawaii at Manoa, 2023) Idle, Jessica Lauren; Price, Melissa R.; Natural Resources and Environmental Management
With global biodiversity declining, research in reproductive biology is necessary to understand population dynamics and develop strategies for the conservation of threatened and endangered species. Following listing as ‘endangered’ under the Endangered Species Act (ESA) in 1970, the Aeʻo (Hawaiian Stilt, Himantopus mexicanus knudensi) population has steadily increased due to the designation and protection of wetland areas across the main island chain, and conservation actions such as predator control, habitat restoration, and educating the public. However, the species continues to be conservation-reliant, with continued human intervention necessary to maintain populations. This study filled gaps in knowledge regarding survival and reproduction dynamics for Aeʻo. In Chapter 1, I: (1) compiled and evaluated data pertaining to Aeʻo reproduction and survival since they were ESA-listed in 1970; and (2) determined and assessed reproductive trends over time. In Chapter 2, I: (1) calculated chick survival rates; and (2) explored chick home range sizes in relation to patch size and survival. Key results of this thesis were that: (1) overall Aeʻo reproductive success has not changed over the last 50 years, though there have been increases in nesting and fledging success; (2) chick movement is restricted by barriers such as roads, fences, and developed areas; and (3) chick mortality is high, with 86% of chicks perishing in the first seven days of life. This information, amongst other results and outputs within this thesis, may be useful in decision-making, future analyses, and implementing management actions. Also included in this thesis are recommended management actions based on the results of this study.
Where To Aim: Evaluating Miconia Management With Herbicide Ballistic Technology In Maui
(University of Hawaii at Manoa, 2023) Lewis, David; Oleson, Kirsten L.; Natural Resources and Environmental Management
Introduced on Maui in the early 1970’s, Miconia calvescens spread unabated until formally recognized as an invasive species in 1991. In 2012, herbicide ballistic technology (HBT) became the primary treatment method for the inaccessible terrain of east Maui. Eradication efforts have been unsuccessful, and the Maui Invasive Species Council has declared Miconia calvescens as economically beyond eradication. With limited funding and invasion potential increasing, ad hoc prevention strategies are no longer viable and alternative management approaches are needed for miconia. My thesis research developed a bioeconomic model to forecast miconia invasion outcomes under different management scenarios countering the dispersal of incipient populations with explicit spatial and temporal components across decadal timescales. Biological and economic outcomes are evaluated after the culminating time step. In chapter 2, a first iteration was coded on a set of defined management actions: (i) inaction, (ii) containment, and (iii) asset protection, where protection under management and damage without management were calculated as benefit-cost ratios. The model forecasted incipient invasions accruing $295k in present value damages over 20 years without management. Additionally, the benefits of management and the preference between offensive containment and defensive protection were influenced by the value and proximity of the conservation assets. Here, containment strategies were preferred when interventions were spatially closer to the maternal source and with greater distance from assets are further away. In Chapter 3, I tested a second model, management actions were assessed based on return on investment per $1000 of future plants prevented. The results indicated that containing the invasion closer to the maternal source was the most cost-effective approach with the highest return on investment. Overall, in both scenarios the model also demonstrated that aggressive management actions are the most cost-effective approach, with benefit cost ratios and returns on investment better than more permissive approaches in all scenarios.
Breeding Ecology and Management of Pueo (Hawaiian Short-eared Owl, Asio flammeus sandwichensis)
(University of Hawaii at Manoa, 2022) Wang, Olivia; Price, Melissa R.; Natural Resources and Environmental Management
Short-eared Owls (Asio flammeus) are an appropriate study species for understanding intraspecific variations in life-history traits in raptors due to their global distribution across continental and island systems at a variety of latitudes. In Hawai‘i, little is known about the ecology of Pueo (Hawaiian Short-eared Owls, A. f. sandwichensis), but populations are thought to be in decline and are state-listed as endangered on O‘ahu. While studies of other Short-eared Owl subspecies serve as a starting point for creating conservation plans for Pueo, initial research has indicated differences in diet, habitat use, and movement ecology of Pueo versus continental Short-eared Owls. Given these differences, further regional studies from Hawai‘i are necessary to ensure management actions adequately address the needs of Pueo. In Chapter 2 of this study, I investigated the breeding ecology of Pueo using a collaborative approach to combine results from targeted nest-searching at two focal study sites on O‘ahu with incidental reports of Pueo nests across the Hawaiian Islands. In Chapter 3 I used these results to draft management recommendations to minimize disturbance to breeding Pueo. At our focal study sites, I found that Pueo select sites with greater vegetation height and density than the surrounding environment for nesting, but that these same vegetation characteristics do not necessarily correlate to increased nest survival. The diet of breeding Pueo was relatively diverse and contained more bird prey when compared to that of North American and European Short-eared Owls. However, diet did not differ significantly among breeding Pueo pairs. Across both focal study sites and incidental observations, Pueo nest initiation spanned November through July, with a peak in February and March. Pueo breeding habitat ranged from non-native dry grasslands at low-elevation to high-elevation native wet forest, showing a marked increase in breeding habitat diversity compared to North American and European Short-eared Owls. Our results establish a basis for informing Pueo conservation in Hawai‘i, including recommendations towards reducing different types of nest disturbance and data to inform spatial and temporal nest buffers. State-wide management actions must account for the expanded breeding season and diversity of breeding habitat types of Pueo.
An Investigation Of The Benefits And Challenges From Entrepreneurial Economic Models For Hawai‘i ‘āina-based Nonprofits
(University of Hawaii at Manoa, 2021) Coffee, Natalie; Idol, Travis W.; Natural Resources and Environmental Management
‘Āina-based education supports biocultural land restoration efforts in Hawai‘i and involves place-based and spiritual learning. Nonprofits across the state facilitate this effort; however, most do not currently have adequate resources to maintain and expand their mission (Johnson et al., 2020). Nonprofits face difficulties when they are not generating sufficient revenue (Andersson et al., 2012), and while substantial aid has been made available to many organizations during the ongoing COVID-19 pandemic, for many, the pandemic has further exacerbated the difficulties they face in obtaining resources (Johnson et al., 2020). The majority of Hawai‘i nonprofit stewardship groups have recently reported a decrease in volunteer participation and losses in funding in the months following the onset of the pandemic (Dacks et al., 2021). The objective of this study was to investigate how ‘āina-based nonprofits can begin to use their existing resources to attain and maximize long-term nonmarket and market benefits associated with ‘āina-based food production. A case study was conducted to address the question: “What are the benefits and challenges of entrepreneurial economic models for ‘āina-based nonprofit organizations in Hawai‘i?” A logic model was then constructed to identify the benefits. Strategies for maximizing the net benefits of entrepreneurship were identified to assist ‘āina-based nonprofits with their service-oriented missions.
Characterizing rainfall regime changes and estimating the timing of high streamflow events across the five main Hawaiian Islands
(University of Hawaii at Manoa, 2022) Gayte, Maxime; Tsang, Yinphan; Natural Resources and Environmental Management
Changes in extreme precipitation and associated floods attract a lot of attention because of their devasting consequences on societies and ecosystems. Despite rainfall is recognized as the dominant driver of streamflow, we still lack the understanding on how extreme rainfall has changed spatially and temporarily, and we still lack the understanding on the relationships between rainfall and streamflow responses in Hawaiʻi. These unresolved questions and less-understood relationships between rainfall and streamflow can undermine our infrastructure planning and emergency responses. This study utilized hourly rainfall and Generalized Extreme Value (GEV) distribution to examine the changes in rainfall regime across the five main Hawaiian Islands. Temporal patterns of annual maximum hourly rainfall were also examined using circular statistics. Lastly, occurrence dates of high streamflow events induced by rainfall were estimated by establishing relationships between rainfall events, soil moisture conditions, and streamflow data using multilinear regressions. Dominant decreasing trends in extreme rainfall were highlighted across the main Hawaiian Islands, at the exception of Hawai‘i Island and Kaua‘i. Circular analysis indicated that annual maximum hourly rainfall occurred principally during the wet season (April-November), and more specifically from mid-December to early January. On another hand, occurrence dates of high streamflow events induced by rainfall events were correctly identified in the two study sites, when incorporating antecedent soil moisture conditions to rainfall observations. For locations where in-situ measurements of soil moisture contents are not available, this study also provided an empirical solution to estimate with a great accuracy soil moisture contents of the surface layer. This added knowledge on extreme rainfall trends and their consequential streamflow will improve our understanding of the patterns, timing, and locations of these extreme events, and assist to design and implement policies and infrastructure to minimize their threats in Hawaiʻi.
Using Stakeholder Objectives to Inform Fire Resource Management in Waiʻanae Hawaiʻi
(University of Hawaii at Manoa, 2022) Cleveland, Rachael; Oleson, Kirsten L.; Natural Resources and Environmental Management
Predicting the social and ecological impacts of natural resource management can be a highly technical task involving complex modeling. However, in many contexts, data and technical capacity are limited and system uncertainty is high. Moreover, affected people may distrust incomprehensible black box models and resist management recommendations stemming from these tools. Decision support tools that overcome these challenges can facilitate moving from planning to action. One such tool is Fuzzy Cognitive Mapping (FCM), a modeling process suited to complex situations where data are scarce and uncertainty is high. FCM relies on people’s perceptions to build a mental model of important system elements and their relative impacts on system dynamics and outcomes. FCM mental models then can be embedded in other decision support processes, such as Structured Decision Making (SDM), to rigorously evaluate the trade-offs across stakeholder objectives of alternative management options. In natural resource management applications, building FCM with stakeholders within a participatory SDM process has the distinct advantage of increasing transparency, representativeness, and trust. My research used FCM and SDM to investigate how fire impacts ecosystem services and how FCM and SDM can be used together to aid the decision-making process for one group of landowners in Waiʻanae, Hawaiʻi. Fires are increasing in frequency in Hawaiʻi, affecting increasingly more areas, people, and economic sectors. Land managers struggle to incorporate stakeholder knowledge and feedback when making fire management decisions. I used FCM to build mental models capable of evaluating the feedback between stakeholder values for ecosystem services and fire resource management actions. I embedded the FCM in an SDM process that directly involved stakeholders in the fire management decision process, specifically to identify values and potential management alternatives, and to transparently discuss consequences and trade-offs. Biodiversity, water resources, and spiritual experience were the most frequently raised ecosystem services valued by the stakeholders, and native species outplanting was the fire management activity that supported these ecosystem services the most. The methodologies used in this study can be applied to other decision scenarios to predict ecosystem service outcomes from alternative fire management strategies and improve the inclusion of stakeholder values in fire management decision-making. FCM provides an easy and cost-effective way to model consequences within an SDM process that is transparent and engages stakeholders.
Uncovering Migratory Patterns Of The Native Hawaiian Freshwater Goby, ‘O‘opu Nākea (Awaous Stamineus)
(University of Hawaii at Manoa, 2022) Ching, Cody; Ching, Cody L.; Natural Resources and Environmental Management
Hawaiʻi is home to ʻoʻopu nākea, a culturally significant, endemic, freshwater goby that exhibits an amphidromous life history. Despite their importance in Hawaiian traditions and their ecological role in freshwater systems, we still lack understanding of their migratory patterns and life history due to the difficulties in determining the environmental factors that form their migratory paths and fish age. This study examined whether different environmental factors, such as amount of rainfall, streamflow, and water chemistry, play a role in (1) the migratory flexibility of A. stamineus and/or (2) the larval duration periods. I sampled 90 individuals from the lower, mid-, and upper-reach of three streams across a rainfall gradient on the windward side of the island of Oʻahu (Kahana, Kahaluʻu, and Waimānalo streams). Using otolith elemental analysis, I examined Sr:Ca ratios to determine if individuals spent their larval period in the ocean (migrants) or if they never left the freshwater streams (residents). I found that 89/90 of the otoliths that were adequately sampled had clear marine levels of strontium, showing very limited flexibility in an amphidromous life cycle. Migratory abilities and larval durations do not seem to be affected by the amount of rainfall a stream receives. This study is a key step in understanding the life history of ʻoʻopu nākea, and it highlights the importance of upstream, downstream connectivity for the survival of amphidromous species. Additionally, this local study of A. stamineus life history will contribute to the global knowledge of amphidromous fish species to better inform management and conservation practices to increase populations worldwide.
Hawaiian Waterbirds and Indigenous Wetland Agroecosystems
(University of Hawaii at Manoa, 2022) Opie, Eryn; Price, Melissa R.; Natural Resources and Environmental Management
Conventional methods of land management often decrease regional biodiversity and heterogeneity, a key driver of landscape, community, and ecosystem dynamics. For example, Ameri-European colonization of the Hawaiian Islands in the early 1800’s led to deforestation, the diversion of water for export agriculture, and the introduction of invasive species and disease, resulting in a loss of native biodiversity. Restoration of heterogeneous landscapes using multi-objective approaches, as found in Indigenous resource management (IRM), may increase biodiversity. However, few studies to date have examined outcomes of IRM for avian biodiversity. To address this research gap, in this study I: (1) assessed the distribution and abundance of native and non-native avian species across restored and unrestored ecosystems in Heʻeia, Oʻahu, within the Heʻeia National Estuarine Research Reserve, a landscape managed using Indigenous resource management practices; and (2) determined the habitat preferences of two endangered waterbirds, Aeʻo (Hawaiian Stilt; Himantopus mexicanus knudseni) and ʻAlae ʻula (Hawaiian Gallinule; Gallinula gallinula sandvicensis), within loʻi kalo agroecosystems. I found that ecosystems in active and restored states supported higher native shorebird and waterbird species richness and abundance compared to unrestored systems. However, native forest birds and seabirds were not detected. Aeʻo and ʻAlae ʻula adults and juveniles partitioned the loʻi kalo habitat temporally and spatially, resulting in year-round use of the site for foraging and nesting. Aeʻo prefered loʻi with low vegetation height and low kalo canopy cover. ʻAlae ʻula prefered loʻi with higher kalo density and more open water. Further, waterbirds foraged more often in loʻi managed at a higher frequency, suggesting that farming activities increased foraging opportunities. These results demonstrate that resource management practices rooted in Indigenous knowledge can contribute to the recovery of native waterbird and shorebird abundance and should be integrated with strategic planning to compensate for habitat lost to sea level rise. Targeted actions such as disease control, removal of invasive predators, and restoration of preferred plant species will be critical to enable recolonization by native forest birds and seabirds.
Enhancing the Role of Surfing in Biodiversity Conservation and Community Development in Indonesia
(University of Hawaii at Manoa, 2021) Ogden-Fung, Cameron; Vaughan, Mehana; Natural Resources and Environmental Management
Indonesia is widely recognized as a global priority for marine conservation due to its high marine biodiversity, yet these important coral reef ecosystems and their associated fisheries are experiencing extensive decline and increasing threats at global and local scales. With around 80% of Indonesia’s 270 million population relying on the richness of their surrounding ocean, it is essential to maintain healthy marine ecosystems that support the culture, economy, and food security of the nation. The Surf Conservation Partnership (SCP) — a collaboration among two NGOs, Conservation International (CI) and Save The Waves Coalition (STWC), mobilizes surfing communities to create surf protected areas (SPAs) that conserve important coastal ecosystems and strengthen community development. Stakeholder analyses can help ensure that objectives of the government and NGOs are in alignment with the ecological and societal goals of the local community. This master’s study aims to examine the issues that shape surf tourism and conservation efforts on Morotai Island, Indonesia, in order to improve collaborative planning processes and governance strategies. This project identifies and explores multiple stakeholder perspectives to better understand the needs of and barriers to sustainable surf tourism and surf conservation development. Semi-structured interviews and an online survey were conducted with representatives of each of the identified stakeholder groups: Morotai community; government officials; NGO employees; and surf tourists. The four key themes that intersected multiple stakeholder groups were empower local community participation, establish local economic benefits, conserve natural resources, and build a collaborative vision. This research contributes new knowledge to the emerging field of surf conservation through a stakeholder analysis lens. The findings provide resource managers and policymakers with recommendations to advance the social-ecological success of surf tourism and conservation development in Indonesia.
Developing a Semi-automated Random Forest Classification Scheme to Analyze Burned Area Using LANDSAT Imagery in Southern India
(University of Hawaii at Manoa, 2021) Earl, Allyson Rae; Trauernicht, Clay; Natural Resources and Environmental Management
Fire regimes, or the pattern, frequency, and intensity of fires over a landscape, has begun to shift over much of the dry tropical regions of the world. The complexity of the pressure fire exerts on the landscape is intensified by the intimate relationship humans have cultivated with this process, especially in regions where traditional burning has taken place. However, the departure from the pre-historic and more recent historical use of fire as a management tool, generally due to conservation regulations, presents unique research challenges to understand how major shifts in human relationships to fire, management regulations of fire prone ecosystems, and vegetation composition, may be driving changing fire behavior and regime. The Biligiriranganatha Hills Temple Reserve (BRT) and Sathyamangalam Forest Reserve (SFR) are adjacent protected areas southern India have similar ecologies, rainfall seasonality, yet have different histories of regulation, species invasions, and human resource use, within the last two decades that may result in key differences in fire regimes. This study therefore sought to construct a fire history across this region to quantify potential differences in burning patterns, compare these patterns to those available with MODIS burned area product (MCD64A1.006), and to explore the potential of this detection method to evaluate and characterize frequency and the proportion of area burned across landcover types (forest, savanna, and other). I used Landsat 7 remotely sensed data and the Random Forest algorithm in Google Earth Engine to develop a semi-automatic method to detect burned area across a time series. The RF classifier was trained using a subset images in which burned pixels were manually classified and then used identify burned area across all available images from 2003-2019 (N= 115 images). Separate classifiers were developed over ~ 5-year time steps due to computational limitations but demonstrated high overall accuracy at 99% for unclassified pixels within the training images and 98% for images not included in the training data. Classified images were composited to develop annual fire maps that were accurate to the Landsat resolution (30M). the Landsat product performed far better at detecting small fires not flagged by MODIS and, in cases of large fires, created fire perimeters similar to MODI. The majority of burned pixels in both reserves experienced burns approximately every 3-4 years. The proportion of burned area by land cover type was highest for savanna in both reserves and the proportion of burned area in forest was higher in BRT than in SFR, potentially indicating landscape-level shifts in ecosystem flammability. Overall, this study developed an efficient semi-automatic classification system for Landsat 7 data that created 30m resolution annual fire summaries which can be used to better inform on the ground research by Indian conservation organizations.

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