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Background: The cellular signaling mechanisms and morphogenic movements involved in axis formation and gastrulation are well conserved between vertebrates. In nearly all described fish, gastrulation and ...
Citation Citation
- Title:
- Gene Expression Patterns That Support Novel Developmental Stress Buffering in Embryos of the Annual Killifish <i>Austrofundulus limnaeus</i>
- Author:
- Wagner, Josiah T., Podrabsky, Jason E.
- Year:
- 2015
Background: The cellular signaling mechanisms and morphogenic movements involved in axis formation and gastrulation are well conserved between vertebrates. In nearly all described fish, gastrulation and the initial patterning of the embryonic axis occur concurrently with epiboly. However, annual killifish may be an exception to this norm. Annual killifish inhabit ephemeral ponds in South America and Africa and permanent populations persist by the production of stress-tolerant eggs. Early development of annual killifish is unique among vertebrates because their embryonic blastomeres disperse randomly across the yolk during epiboly and reaggregate several days later to form the embryo proper. In addition, annual killifish are able to arrest embryonic development in one to three stages, known as diapause I, II, and III. Little is known about how the highly conserved developmental signaling mechanisms associated with early vertebrate development may have shifted in order to promote the annual killifish phenotype. One of the most well-characterized and conserved transcription factors, oct4 (Pou5f1), may have a role in maintaining pluripotency. In contrast, BMP-antagonists such as chordin, noggin, and follistatin, have been previously shown to establish dorsal-ventral asymmetry during axis formation. Transcription factors from the SOXB1 group, such as sox2 and sox3, likely work to induce neural specification. Here, we determine the temporal expression of these developmental factors during embryonic development in the annual killifish Austrofundulus limnaeus using quantitative PCR and compare these patterns to other vertebrates. Results: Partial transcript sequences to oct4, sox2, sox3, chordin, noggin-1, noggin-2, and follistatin were cloned, sequenced, and identified in A. limnaeus. We found oct4, sox3, chordin, and noggin-1 transcripts to likely be maternally inherited. Expression of sox2, follistatin, and noggin-2 transcripts were highest in stages following a visible embryonic axis. Conclusions: Our data suggest that embryonic cells acquire their germ layer identity following embryonic blastomere reaggregation in A. limnaeus. This process of cellular differentiation and axis formation may involve similar conserved signaling mechanisms to other vertebrates. We propose that the undifferentiated state is prolonged during blastomere dispersal, thus functioning as a developmental stress buffer prior to the establishment of embryonic asymmetry and positional identity among the embryonic cells.
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182. [Article] Feral Swine Action Plan for Oregon
Feral swine are defined as free roaming animals of the genus Sus that are not being held under domestic management or confinement. Swine have spread from Europe and Russia to habitats around the world ...Citation Citation
- Title:
- Feral Swine Action Plan for Oregon
- Author:
- Sytsma, Mark, Rouhe, Arick Christopher
- Year:
- 2007
Feral swine are defined as free roaming animals of the genus Sus that are not being held under domestic management or confinement. Swine have spread from Europe and Russia to habitats around the world via human introduction. Currently, feral swine populations are established on every continent except Antarctica. Unlike other large mammal invaders, swine have a high reproductive capacity and are omnivorous, which allows for a quick assimilation into most habitats. Once a breeding population is established in an area, the population can quickly increase and negatively impact the ecosystem. A successful invasion of feral swine is difficult, and sometimes impossible, to reverse. A feral swine pest risk assessment for Oregon, released in 2004, designated feral swine as a very high-risk species due to high potential for establishment, environmental and economic impacts, and disease transmission to wildlife, livestock and humans. Economic impacts on ecosystems and disease transmission to wildlife are difficult to assess, but restoration of ecosystems and losses to agriculture and livestock have been estimated to exceed US$800 million in the United States each year. Environmental impacts include facilitation of noxious weed invasions, shifts in dominant plant species, reduction of forest regeneration, and soil erosion. Facilitation of noxious weeds and erosion due to feral swine rooting are documented in Oregon. Feral swine in Oregon have not been implicated in disease transmission to humans, but the recent E. coli outbreak from spinach grown on a California farm that caused three deaths has been genetically traced to feral swine excrement deposited in spinach fields. The feral swine population in Oregon is currently small and dispersed. Few disturbances have been documented but state and federal biologists report regular occurrence of disturbances due to feral swine. Actions to prevent the effects of an invasion fall into three categories: management, control or eradication. Of the three categories, only eradication efforts have successfully slowed or reversed the effects of swine invasions. Case studies from California, Australia, Hawaii, the Galapagos Islands and the Channel Islands off the coast of California show that management and control efforts, while effective in the short term, have not successfully kept small feral swine populations from increasing to levels that are unmanageable and uncontrollable. A four-year feral swine eradication plan is proposed. The Plan includes recommended legislative changes to facilitate eradication, outreach and education, population assessment, rapid response, and eradication elements. A 0.5 FTE position is required at the Oregon Department of Fish and Wildlife to implement the plan. Eradication of feral swine in Oregon is estimated to require a four-year, $1.29 million effort. Follow-up control of new releases and escapes will require a maintenance effort estimated at less than $50,000 per year (excluding contingency funds for emergency response). These costs are small relative to the value of the $3.6 billion Oregon agriculture and livestock industries and the investment Oregon has made in riparian restoration efforts. Sustained control of feral swine in Oregon will require a longterm commitment that will include annual domestic swine marking, education, and monitoring.
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183. [Article] Siltcoos Lake Nonpoint Source Implementation Grant: Water Quality Conditions and Nutrient Sources
Siltcoos Lake is a large (1280 hectares), shallow (mean depth 3.3 m; maximum depth 6.7 m) lake located on the Central Oregon Coast, just south of Florence and bordered by Dunes City, Oregon. The outflow ...Citation Citation
- Title:
- Siltcoos Lake Nonpoint Source Implementation Grant: Water Quality Conditions and Nutrient Sources
- Author:
- Sytsma, Mark D., Miller, Rich
- Year:
- 2010
Siltcoos Lake is a large (1280 hectares), shallow (mean depth 3.3 m; maximum depth 6.7 m) lake located on the Central Oregon Coast, just south of Florence and bordered by Dunes City, Oregon. The outflow and water level of Siltcoos Lake is regulated by a dam on the Siltcoos River 4 km upstream from the Pacific. Several permanent streams feed the lake from its 176 square kilometer watershed including Fiddle Creek, Maple Creek, and Woahink Creek, the outflow from Woahink Lake. Much of the watershed is forested and used for timber harvest, residential development, and limited agricultural production. The lake is popular for recreational activities, particularly fishing for wild coastal Coho salmon, rainbow trout, cutthroat trout, largemouth bass, bluegill, crappie, and yellow perch (Buckman 2004). The lake is also the domestic drinking water source for approximately 125 of the 1330 residents of Dunes City and numerous residents outside the city limits within Lane and Douglas Counties (LCOG 2002). During the fall of 2007 a dense bloom of the potentially toxigenic blue-green algal species Anabaena planktonica prompted Dunes City, the South Coast Water District, the Lane County Health Department, and the Oregon Department of Human Services to issue an advisory against usage of Siltcoos Lake water for drinking and other domestic use (DHS 2007). Residents dependent upon Siltcoos Lake were forced to find alternate domestic water sources for a total of 52 days. This incident was part of a long history of water quality problems including dense algal growth and excessive growth of the non-native aquatic macrophytes Brazilian elodea (Egeria densa), parrotsfeather (Myriophyllum aquaticum), and two-leaf water milfoil (Myriophyllum heterophyllum) (Pfauth and Sytsma 2005; Johnson et al. 1985; McHugh 1979). Because of the water quality problems, the Oregon Department of Environmental Quality (DEQ) placed the lake the 303(d) list of impaired water bodies; specifically due to violations of the “aquatic weeds and algae” water quality criterion (DEQ 1998; DEQ 2006). Dunes City has acted on water quality concerns for both Siltcoos and Woahink Lakes by issuing a temporary building moratorium (Dunes City 2006a), a septic tank maintenance ordinance (Dunes City 2006b), and an ordinance limiting phosphorus use (Dunes City 2007). Preliminary assessments (Johnson, et al. 1985, LCOG 2002) indicate multiple sources of water quality problems including excess nutrient and/or sediment loading from residential development, poorly functioning on-site septic systems, private forestry and agricultural practices and introductions of non-native aquatic plant species. This report summarizes data collected by Portland State University and project partners between June 2008 and May 2009 to better define water quality conditions within the lake as well as potential nutrient sources. Physical, chemical, and biological data were collected at lake and tributary sites over the one year period. Data were evaluated across sites, depth and the season. The information collected will contribute to total maximum daily load (TMDL) development for the Midcoast Lakes and can be used to identify and prioritize restoration activities in the Siltcoos Lake watershed.
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Pacific lamprey is a culturally valuable species to indigenous people, and has significant ecological importance in freshwater and marine ecosystems. Over the past several decades, constrictions in range ...
Citation Citation
- Title:
- Investigations of Larval Pacific Lamprey Entosphenus tridentatus Osmotic Stress Tolerance and Occurrence in a Tidally-Influenced Estuarine Stream
- Author:
- Silver, Gregory Shell
- Year:
- 2015
Pacific lamprey is a culturally valuable species to indigenous people, and has significant ecological importance in freshwater and marine ecosystems. Over the past several decades, constrictions in range and reductions in Pacific lamprey abundance have been observed in Western North America, and may be indicators of range-wide declines. In the face of declining populations, the U.S. Fish and Wildlife Service has partnered with tribal, state, federal, and local entities to implement a regional Pacific lamprey conservation agreement aimed at reducing threats to Pacific lamprey and improving their habitats and population status. Research needs identified in the conservation agreement include assessing larval Pacific lamprey occupancy and distribution, habitat requirements, and the limiting factors of larval distribution in the freshwater ecosystem. As part of the effort to address these knowledge gaps, we investigated the potential for larval lampreys to occur in tidally-influenced estuarine environments. Research of this type may be valuable for future conservation, management or recovery efforts of Pacific lamprey throughout its range. We employed a two-phased approach, consisting of laboratory and field components to address our aims. We first conducted a series of controlled laboratory experiments to evaluate osmotic stress tolerance and osmoregulatory status of larval Pacific lamprey exposed to a range of (1) fixed salinity in various dilutions of saltwater and (2) oscillating salinity treatments designed to simulate tidal activity. Tolerance was assessed by monitoring and comparing survival of larvae in various treatments through 96 h. Osmoregulatory status was assessed by quantifying and comparing total body water content, plasma osmolality, and plasma cation (i.e., sodium) concentrations among larvae surviving various treatments. In fixed salinity experiments, 100% survival was observed in 0‰, 6‰, 8‰ and 10‰ through 96 h, while 0% survival was observed through 48 h in 12‰, 30 h in 15‰, and 12 h in 25‰ and 35‰. In oscillating salinity experiments, on the other hand, a significant increase in survival (100%) was observed through 96 h in treatments that oscillated between 12‰ and 0‰ (freshwater) at about 6 h intervals versus fixed 12‰ salinity experiments. A significant increase in survival also occurred in oscillating 15‰ treatments (60%) versus fixed 15‰ through 96 h. Linear regression analysis indicated higher environmental salinity in laboratory experiments was significantly related to increases in plasma osmolality and plasma sodium (the most abundant osmotically active plasma cation) concentrations, and concurrent decreases in total body water content among larvae that survived various treatments. Tidal oscillations in salinity appeared to temper the desiccating effects of salinity, as changes in body water content and sodium ion concentration were less abrupt than fixed salinity treatments. These results suggest larvae cannot osmoregulate in hyperosmotic environments, but are able to tolerate some fixed and oscillating hyperosmotic salinity exposure. Consequently, larvae may be able to occur in certain areas of estuaries, such as oligohaline habitats that are characterized by low levels of salinity. Experimental results were used, in part, to guide larval sampling in a tidally-influenced habitat. Occurrence of larval Pacific lamprey and Lampetra spp. (western brook and river lampreys) was subsequently investigated across a gradient of salinity in Ellsworth Creek (Pacific County, Washington) by electrofishing. Larval Pacific and Lampetra spp. were detected within an approximately 300 m long tidally-influenced segment of the study area. Salinity monitoring was conducted in six tidally-influenced reaches where larvae were detected for up to 14 d following electrofishing. Maximum tidal cycle salinity exceeded 15 ppt during 52% to 80% of tidal cycles within tidally-influenced reaches where larvae were detected. These results suggest potential for larval lamprey to occur in certain portions of tidal estuaries. However, long-term residence of larvae in tidally-influenced habitats and whether larvae are able to subsequently survive, grow, transform, and out-migrate is not known and requires further study. Given the potential for tidally-influenced habitats to be occupied by larvae, assessments of larval occurrence in other areas, such as the lower Columbia River, may be warranted. Knowledge of larval lamprey distribution in estuarine environments may be valuable for habitat restoration, and mitigating potential impacts from dredging and other human disturbances.
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185. [Article] Sablefish (Anoplopoma fimbria) Scarcity and Zooarchaeological Data Quality in Northwest Coast Archaeological Sites
Sablefish (Anoplopoma fimbria) is a scarcely represented species in Northwest Coast archaeology, but its remains are abundant at Tse-whit-zen, a large, Lower Elwha Klallam village in modern Port Angeles, ...Citation Citation
- Title:
- Sablefish (Anoplopoma fimbria) Scarcity and Zooarchaeological Data Quality in Northwest Coast Archaeological Sites
- Author:
- Nims, Reno
- Year:
- 2016
Sablefish (Anoplopoma fimbria) is a scarcely represented species in Northwest Coast archaeology, but its remains are abundant at Tse-whit-zen, a large, Lower Elwha Klallam village in modern Port Angeles, WA that was occupied over the past 2,800 years. Because sablefish flesh has high nutritional value and it can be easily captured from nearshore waters in its juvenile form, sablefish should have been pursued where it was available. Therefore, the scarcity of sablefish in many Northwest Coast archaeological sites could indicate this species was not abundant in past fisheries. However, current zooarchaeological reports do not contain sufficient information on taphonomic histories, sampling, or zooarchaeological methods to determine whether patterns of sablefish scarcity could actually explained by differential destruction of sablefish remains, sample size effects, screen size effects, or misidentification. In this thesis, I examine how each of these factors may have affected the abundance of sablefish remains in Northwest coast archaeological sites. I evaluate four hypotheses that attribute sablefish representation to zooarchaeological identification methods, screen size, sample size, and post-depositional destruction of fishbone. While I do not explicitly test whether social and ecological factors affect sablefish abundance, sociocultural and environmental variation can be considered likely explanations for the observed patterns of sablefish representation if the other hypotheses are rejected. I test my hypotheses using three scales of archaeological records. First, I reanalyzed six previously analyzed Salish Sea assemblages to assess whether criteria for sablefish identification exist, are valid, and have been applied consistently. Second, I synthesized fishbone data from 35 previously analyzed Northwest Coast assemblages to evaluate the effects of screen size, sample size, and post-depositional destruction on sablefish representation. Finally, I integrate previously unreported fishbone data from the analysis of Tse-whit-zen into the synthesis of previous studies. The Tse-whit-zen materials I report on here represent six discrete time periods in the 1,800-year history of one large area of the site, which encompasses part of a plankhouse, providing a unique opportunity to examine the effects of screening, sample size, and post-depositional destruction at an extremely fine scale. I also use data from the reanalysis of a portion of the Tse-whit-zen fishbone to verify the consistency of sablefish identification for this site. I reject all four hypotheses and conclude that the uneven distribution of sablefish is likely a true reflection of ecological factors, human decision-making, or both factors. Whether sablefish scarcity is related to distributions of sablefish in past environments, or whether humans chose not to pursue sablefish is not known from the current study. Connecting sablefish capture to specific seasons with body-size regression methods may reveal associations between sablefish acquisition and other seasonal fisheries and activities, and help evaluate whether they conflicted with sablefish procurement in some contexts. Although zooarchaeological identification and reporting methods do not appear to account for sablefish scarcity, zooarchaeologists need to include more information about their methods so that the validity of inter-assemblage comparisons can be assessed. Zooarchaeologists maximize the value of their contributions to anthropology, biological sciences, and human ecodynamics when they explicitly report the methods they use to identify animal remains. By reporting the methodological and analytic procedures they used in detail, zooarchaeologists enhance the reader's confidence in their conclusions and provide future researchers with the information that is required to replicate their results. Which elements were recorded, and the criteria that were used to make taxonomic attributions, fundamentally affect the primary faunal data that researchers use. This study is part of a growing interest among zooarchaeologists in data quality assurance and quality control, which constitute a critical part of every large-scale comparative analysis.
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Nonindigenous species have caused substantial environmental and economic damage to coastal areas. Moreover, the extent and impacts of nonindigenous species are increasing over time. To develop predictive ...
Citation Citation
- Title:
- Broad-Scale Non-indigenous Species Monitoring along the West Coast in National Marine Sanctuaries and National Estuarine Research Reserves
- Author:
- de Rivera, Catherine E., Ruiz, Greg, Crooks, Jeff, Wasson, Kerstin, Lonhart, Steve, Fofonoff, Paul, Steves, Brian, Rumrill, Steven S., Brancato, Mary Sue, Pegau, Scott, Bulthuis, Doug, Preisler, Rikke Kvist, Schoch, Carl, Bowlby, Ed, DeVogelaere, Andrew, Crawford, Maurice, Gittings, Steve, Hines, Anson, Takata, Lynn, Larson, Kristen, Huber, Tami, Leyman, Anne Marie, Collinetti, Esther, Pascot, Tiffany, Shull, Suzanne, Anderson, Mary, Powell, Sue
- Year:
- 2005
Nonindigenous species have caused substantial environmental and economic damage to coastal areas. Moreover, the extent and impacts of nonindigenous species are increasing over time. To develop predictive models and to identify which areas should be targeted for impact mitigation or early detection, we need a basic foundation of knowledge about the spatial and temporal patterns of invasions. This project was developed because we lacked the necessary data to rigorously evaluate the patterns of coastal invasions. This collaborative project, between the Smithsonian Environmental Research Center, the National Estuarine Research Reserve System (NERRS) and the National Marine Sanctuary Program (NMSP), established a rigorous, largescale monitoring and research program for invasive species in nine protected coastal areas along the US West Coast from San Diego, CA, to Kachemak Bay, AK. Our research included two components, broad-scale and site-specific projects. The broad-scale component focused on using standardized protocols to collect data on the composition of fouling communities and nearshore fish and crabs. We collected data from 310 settling plates and 140 traps across nine NERRS Reserves and NMSP Sanctuaries. The four most common taxa on the settling plates were Bryozoa, Tunicata, Cirripedia, and Hydrozoa. We identified these four taxa and also Nudibranchia, a mobile molluscan taxa often associated with fouling organisms, to species and noted which were nonindigenous. We found 132 species in the 5 taxa under study. NIS accounted for over one quarter of the diversity in these taxa, with 31 NIS identified. Over half of tunicate species were non-native. The documented NIS included two new US west coast sitings plus 3 other range extensions. We documented two patterns in NIS, a latitudinal pattern and differences between NIS impacts in marinas versus non-marina sites; research on salinity differences is still underway. Both the number and percent of NIS decreased with increasing latitude. Tijuana River had the most, 21, NIS and Monterey Bay had the highest proportion of NIS (57%). The same pattern of decreasing NIS with increasing latitude was observed when we examined Tunicata only and Bryozoa only. Across latitudes, plates in marinas were more impacted by NIS than were plates in more natural areas. All NIS but one were found at marinas, whereas only half the NIS were found at the non-marina sites. In addition, NIS at marinas accounted for almost 80% of the NIS per site. Therefore, we were able to provide information on the relative risk of invasions for different taxonomic groups and geographic regions. The spatial and habitat patterns can be used for future predictions and will be of even more value once they are confirmed with additional taxonomic groups and hypothesis-driven studies that will continue from this initial study. Our broad-scale trapping study illustrated how recently-introduced NIS quickly can become numerically dominant. Although we only found Carcinus maenas at Elkhorn Slough NERR, this recently introduced nonindigenous crab was very common at this Reserve and was the most abundant crab in our traps at 3 of 7 Elkhorn sites. The site-specific projects were conducted at each Reserve plus Olympic Coast and Monterey Bay Sanctuaries. Several are serving as the first important step in longer term research, such as examining whether a change in shipping policy in Kachemak Bay will increase NIS. Others, such as the South Slough project examining the effect of a salinity cline on the number and proportion of NIS, will be expanded to test hypotheses across several protected areas. Many of these site-specific projects still need further analyses, and analysis is underway.
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This thesis considers the question of whether climate change is affecting the migration patterns of geese in the Pacific Flyway, specifically cackling geese (Branta hutchinsii minima) and Pacific white-fronted ...
Citation Citation
- Title:
- Climate Change, Its Effect on Migration Patterns of the Cackling Goose and White-Fronted Goose in the Willamette Valley, and Implications for Goose Management
- Author:
- Warren, Kelly
- Year:
- 2010
This thesis considers the question of whether climate change is affecting the migration patterns of geese in the Pacific Flyway, specifically cackling geese (Branta hutchinsii minima) and Pacific white-fronted geese (Anser albifrons frontalis). Ancillary questions that are considered are as follows: • If global warming is affecting these species, what is the nature of the effects? • How are the changes affecting the human environment and what can be done about these effects? In 1994, the majority of the cackler population in the Pacific Flyway began to winter in Oregon’s Willamette Valley rather than in their historical wintering areas in California’s Central Valley. In recent years, the Pacific white-fronted goose has shown a change in behavior similar to that of cacklers just before their major shift. The reasons for this shift have not been clear, though climate change, agricultural shifts, or competition with other species were thought to be possible causes. Analyses of historical breeding and wintering surveys, bird band data, harvest data, agricultural data, and climate and weather data were undertaken in the course of this thesis to see if the cause or causes could be identified. The results showed that climate and weather data, i.e. an increase in average annual temperature coupled with occasional severe winters, most closely correlated with the cacklers’ shift northward. The data comparison revealed that there is a direct relationship between cacklers and a warming shift seen on the wintering grounds. There also was a secondary correlation between the northward shift and recent changes in agricultural crops in the Willamette Valley. Substantially less data are available for white-fronts, and the relationship between their recent migration changes and climate and/or other factors is much less clear. The following recommendations for management and further study are aimed at more completely understanding the scope and causes of migration shifts and formulating well-founded management plans for geese in the Pacific Flyway: • Continue research to determine if climate change is causing changes in goose population numbers and behavior. • Expand breeding ground flight surveys to include cacklers and habitat preference to learn how habitat change on the Y-K Delta is altering cackler behavior and breeding success. • Expand radio transmitter studies and collar programs for cacklers in Oregon and Washington to verify northerly wintering shifts. • Expand collar programs for cacklers wintering in the Willamette Valley to determine if the population is continuing to shift northward. • Expand banding programs for white-fronted geese to gather more data about migration patterns. • Develop models that will allow researchers and managers to correlate migration behavior with various environmental factors including climate change in order to: 1) determine which factors are causing migration changes in specific waterfowl populations and 2) allow managers to make changes to management plans in advance of rapid changes. • Inform the public about how it can assist in collar surveys or volunteer for the U.S. Fish and Wildlife Service (USFWS). This will enable USFWS to have more concrete data and give the public an opportunity gain a greater understanding of geese and goose management. • Expand research on urban cackling geese to determine the nature and scope of their effect on the human environment and to devise management strategies. • Research energetics in migrating geese to determine whether the shift in migration patterns has its basis in climate change. • Increase data exchange and coordination among agencies. • Formulate and implement plans at the city and county levels to manage growing numbers of geese in urban areas. • Recognize and anticipate the possibility that goose populations may move into new wintering areas and formulate plans for management of those species. • Implement low cost techniques, such as more liberal bag limits and seasons, hazing, etc., to assist agricultural landowners in decreasing goose-related crop damage.
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188. [Article] Assessing Possible Cruise Ship Impacts on Huna Tlingit Ethnographic Resources in Glacier Bay
This report provides a thematic summary of an ethnographic study addressing the effects of cruise ships within Glacier Bay proper on the people known as the Huna Tlingit. Occupying the heart of Glacier ...Citation Citation
- Title:
- Assessing Possible Cruise Ship Impacts on Huna Tlingit Ethnographic Resources in Glacier Bay
- Author:
- Deur, Douglas, Thornton, Thomas
- Year:
- 2014
This report provides a thematic summary of an ethnographic study addressing the effects of cruise ships within Glacier Bay proper on the people known as the Huna Tlingit. Occupying the heart of Glacier Bay National Park and Preserve, Glacier Bay proper is considered to be the core homeland of Huna Tlingit. The Huna occupied the Bay prior to its most recent glaciation and, though they now live nearby in Hoonah and other communities, they have continued to use, occupy, and value the lands and waters within the Bay since the glaciers began to retreat over two centuries ago. Simultaneously, since the designation of Glacier Bay as a unit of the National Park Service, Glacier Bay proper has become the focal point of a thriving tourist industry, with most park visitors arriving in the Bay by cruise ship. In past consultation, Huna representatives have expressed to NPS staff that cruise ships have various adverse effects on lands, resources, and values that are of concern to Huna people. Also, in recent years, the NPS has identified locations within Glacier Bay proper that appear to be eligible for designation as “Traditional Cultural Properties” (TCPs), a type of property that is eligible for listing on the National Register of Historic Places by virtue of its cultural and historical importance to the Huna Tlingit. In light of the presence of these TCPs, as well as a variety of other federal mandates, the NPS must assess the potential adverse effects of park operations on lands and resources of importance to Huna Tlingit— including park specific vessel quotas and operating requirements that set limits on the number and operation of cruise ships. Recognizing this, the NPS initiated the current study to systematically identify the scope and nature of the impacts of cruise ship traffic on lands and resources of importance to Huna people, to illuminate the cultural context of those impacts, and to recommend potential avenues for minimizing or mitigating any adverse effects. No fewer than 50 Huna Tlingit served as formal interviewees for this study, and many others contributed informally to the project’s success. Through interviews with these people, as well as repeat visits to Glacier Bay proper with Huna Tlingit interviewees, the researchers systematically documented the nature and extent of cruise ship effects, as described and understood by Huna people. Interviewees identified a number of “tangible” adverse effects, some historical and some ongoing: air and water pollution, trash dispersal, noise pollution, wakes, fish and wildlife disturbances, various impacts on Tlingit boaters, and increased region-wide exposure to shipborne diseases. Interviewees also identified “intangible” adverse effects: displays of “disrespect” by people on ships, the disruption of Huna connections to Glacier Bay, inappropriate public interpretation, and the effects of outside observers on the character of traditional activities. While particular attention is directed here to the effects of cruise ships on TCPs, most of the effects are understood to have broader effects, throughout large portions of Glacier Bay proper and beyond. Positive effects were also noted, especially economic advantages. Seeking to illuminate some of the challenges and potentials of cruise ship tourism from a Huna perspective, interviews also contrasted cruise ship tourism in Glacier Bay with the Icy Strait Point facility, a cruise ship port with tourist facilities that is run by Huna Totem Corporation. Certain key cultural issues required to conceptualize these effects are also addressed, such as Huna protocols for “respecting” Glacier Bay, traditional Huna concepts of Glacier Bay as uniquely “clean” and spiritually potent, as well as Huna discomfort with the loss of their traditional role as “host” to visitors in their homeland. These elements represent key context for discussions of Huna perceptions of cruise ships, we suggest, and Huna discussions of specific impacts are often only understandable with reference to them. Interviewees recommend a variety of opportunities for minimizing or mitigating these adverse effects of cruise ships in the future management of TCPs and other park lands, waters, and resources. The document advances both specific recommendations and general principles that may be of value in future consultation and communication between Huna and the NPS on matters relating to the future of Glacier Bay.
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189. [Article] Population Structure of Island-Associated Pantropical Spotted Dolphins (Stenella attenuata) in Hawaiian Waters
Understanding gene flow, diversity, and dispersal patterns is important for predicting effects of natural events and anthropogenic activities on dolphin populations. With the very recent exceptions of ...Citation Citation
- Title:
- Population Structure of Island-Associated Pantropical Spotted Dolphins (Stenella attenuata) in Hawaiian Waters
- Author:
- Courbis, Sarah Shelby
- Year:
- 2011
Understanding gene flow, diversity, and dispersal patterns is important for predicting effects of natural events and anthropogenic activities on dolphin populations. With the very recent exceptions of false killer whales (Pseudorca crassidens), spinner dolphins (Stenella longirostris), and common bottlenose dolphins (Tursiops truncatus), Hawaiian odontocete species are managed as single stocks within the U.S. Hawaiian Exclusive Economic Zone. These exceptions are a result of recent studies that have indicated that some species have populations that show fidelity to individual islands or groups of islands, resulting in genetic differentiation, often with management implications. The first part of my study (following the introductory chapter) focused on population structure of pantropical spotted dolphins (Stenella attenuata) near the Hawaiian Islands. Because of the level of human interaction, pantropical spotted dolphin populations need to be defined accurately to be managed in a way that will avoid local population losses, especially given that the commercial and recreational troll fisheries near the islands "fish on dolphins" to catch tuna. I analyzed genetic samples for mtDNA and microsatellite loci from four island regions: Hawai'i, the 4-islands area, O'ahu, and Kaua'i/Ni'ihau. My results support genetic differentiation among the regions of Hawai'i, the 4-islands area, and O'ahu and suggest that pantropical spotted dolphins near Kaua'i/Ni'ihau are likely transient and in very low numbers. There was no strong evidence to support sex-biased dispersal or group fidelity. Possibly, differentiation is mediated by behavior adapted to differing habitat types. From a management perspective, spinner and bottlenose dolphin populations near the Hawaiian Islands have been split into separate stocks for management based on levels of genetic differentiation similar to those found for pantropical spotted dolphins. These precedents suggest that comparable action should be taken to split pantropical spotted dolphin stocks near the Hawaiian Islands. Most population studies rely heavily upon fixation indicies like FST to determine whether populations are genetically differentiated. When FST values are low but significantly different from zero, it can be difficult to interpret the biological significance of these values. As part of my study, I suggest that one way to evaluate whether small FST values indicate significant differentiation is to compare FST values with other populations considered to be separate based on factors such as extreme distance or morphological differences. I examined pantropical spotted dolphins from the coastal and offshore Eastern Tropical Pacificm (ETP), Hawaiian Islands, and China/Taiwan to examine the utility of comparing FST values across separate populations. Among Hawaiian Island regions, FST values are significantly different from zero but small. The comparison of these FST values with more distant populations in the ETP and China/Taiwan indicated that differences among Hawaiian Island regions were similar in magnitude to those found between the offshore and coastal ETP sub-species, but smaller than between the Hawaiian Island regions and the other regions examined. This suggests a level of reproductive isolation among the Hawaiian Islands regions that is comparable to that of offshore and coastal ETP populations, and supports the value of fixation index comparisons in evaluating differentiation among putative populations. My results suggest that assigning specific numerical baseline FST values may not always be biologically meaningful but that determining whether related populations with geographic or other separation show a preponderance of similar, lower, or higher fixation index values can help evaluate whether genetic differences among sympatric or parapatric groups warrants designating them as separate populations for management. Lastly, I explore whether the fast evolving mtDNA control region may be more suited to phylogenetic comparisons among the Stenella than slower evolving gene regions and whether the small number of haplotypes generally used in phylogenetic analyses is adequate for defining relationships among dolphins. Usually, slow evolving regions, such as gene regions, are used in phylogenetic analyses because species and genera have been isolated long enough for variation to have accumulated in such regions but not so long that many reversals (i.e. a mutational change in sequence that later changes back to the original sequence) have occured. The mtDNA control region is typically used for population genetic comparisons rather than phylogenetic comparisons because it is considered to be a fast evolving region. Historically, dolphin phylogeny has been examined using gene regions, which have resulted in ambiguous and unexpected relationships. However, the lack of variation in the mtDNA control region for pantropical spotted dolphin populations and the fact that recent studies have found that the mtDNA control region in cetaceans evolves at about one quarter the rate of other mammals, raises the question as to whether this region would be better suited to phylogenetic studies for the Stenella (and potentially other dolphin species). In comparing 346 haplotypes from five species of Stenella world-wide, I found that the mtDNA control region is probably not a good region to use for phylogenetic analyses, and that even faster evolving regions might perform better. The differences in the mtDNA control region were not sufficient to distinguish clear relationships among the Stenella. I also found that when subsets of haplotypes chosen at random were compared, the results differed among comparisons, suggesting that there is value in using more than the usual one or two haplotypes when making phylogentic comparisons. Given the recent increases in sequence availability (e.g. GenBank) and computing power, researchers should strongly consider using many haplotypes from a variety of populations in their phylogenetic comparisons.