Whale-watching in Juneau, AK: assessing potential effects on humpback whales and understanding passenger perceptions
AuthorSchuler, Alicia Rinaldi
ChairPearson, Heidi C.
Mueter, Franz J.
MetadataShow full item record
AbstractThe feeding grounds of the North Pacific humpback whale (Megaptera novaeangliae) in Juneau, Alaska have rapidly developed into a popular whale watch destination during the summer (May-September). The whale watch industry has tripled in size in the last 18 years, currently numbering approximately 65 vessels. The sustainability of this industry could be jeopardized if the health and dependability of the resource, the whales, is negatively affected by increasing vessel pressure. The aim of this project is to provide a holistic understanding of whale watch tourism in Juneau by assessing 1) humpback whale responses to whale-watching vessels and 2) passenger experiences as a conduit for conservation of whales and the environment. Data were obtained during 2016 and 2017, comprising observations of 201 humpback whale groups and collection of 2331 passenger surveys. To address the first objective, shore-based measurements and observations of humpback whales were conducted to assess potential impacts of whale-watching vessels on short-term movement and behavioral patterns of whales. Linear mixed effects models indicated that the presence (vs. absence) of vessels was related to significantly higher deviation in linear movement, increased swimming speed, and shorter inter-breath intervals (IBI). For each additional vessel present, deviation increased and IBI significantly decreased. Linear regression models also indicated that as time spent in the presence of vessels increased, respiration rate (breaths per minute) increased. Markov chain analyses indicated that 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. To address the second objective, surveys were administered to passengers before, immediately after, and six months after a whale-watching tour to measure knowledge, intentions, behaviors, and attitudes over time. Following a whale-watching tour, awareness of whale-watching guidelines/regulations doubled and support for guidelines/regulations significantly increased and remained high six months later. Binomial logistic regression models determined that strong support for guidelines/regulations was more likely if participants were aware of guidelines/regulations and less likely if participants disagreed that vessels have a negative impact on whales. Lastly, linear regression models revealed that participants that acknowledged human impacts on whales and their habitat had stronger pro-environmental attitudes. As vessel presence increases in this region, adherence to whale watching guidelines/regulations is likely to become increasingly important to mitigate cumulative effects that may arise from short-term changes in whale behavior in a changing environment. It is recommended that management revisit the current measures in place to better suit the industry today, and that education during whale watching tours be included as a potential management tool to encourage operator compliance. The results presented in this thesis indicate that both management and the industry itself can help to develop a mutually beneficial industry for the whale watching operators, the whales, and the people that come to watch them.
DescriptionThesis (M.S.) University of Alaska Fairbanks, 2019
Table of ContentsGeneral Introduction -- Chapter 1: Humpback whale movements and behavior in response to whale watching vessels in Juneau, AK -- Chapter 2: Conservation benefits of whale watching in Juneau, Alaska -- Appendix.
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Humpback whales and humans: a multi-disciplinary approach to exploring the whale-watching industry in Juneau, AlaskaTeerlink, Suzanne F.; Horstmann, Larissa; Witteveen, Briana; Mueter, Franz; DeMaster, Doug; Beaudreau, Anne (2017-05)A booming whale-watching industry in Juneau, Alaska is leading to complicated resource management challenges. Juneau's growing commercial whale-watching industry includes over 60 vessels and generates more than $25 million in annual revenue. As this industry has increased, so too have concerns for the welfare of humpback whales (Megaptera novaeangliae) exposed to this vessel traffic. However, we lack a fundamental understanding of long-term impacts, if any, that vessel disturbance has on humpback whales. Further, we have insufficient data on local abundance and seasonal attendance of humpback whales that are necessary to detect potential future changes. The aim of this project is to investigate Juneau area humpback whales and their interactions with whale-watching tourism to set a foundation for sustainable management of this resource and industry. To reach this objective, three studies were employed. 1) Methods for monitoring humpback whale population parameters through a citizen science program were developed and tested. Photo-identification data were collected on whale-watching platforms and compared to data from dedicated surveys to objectively evaluate the citizen science data collection methods and identify biases. 2) Physiological markers were evaluated for signs of a chronic stress response in blubber of Juneau-area humpback whales compared with humpback whales from other areas in Alaska with far less vessel traffic. The concentrations of several steroid hormones, including cortisol, were measured from biopsy samples and used to infer a relative cumulative stress response in whales exposed to Juneau's tourism fleet. 3) Community perceptions toward Juneau's whale-watching industry and humpback whale management were collated to consider stakeholder concerns and suggestions for local humpback whale management. Participants were given the opportunity to share their perspectives on humpback whale welfare, community considerations and concerns, and recent and proposed management changes that affect the whale-watching industry. I found that citizen science data can produce reliable estimates of abundance, especially with sufficient effort. I did not find evidence for increased stress response in Juneau-area humpback whales and argue that this indicates habituation in these animals. Respondents in our survey generally supported Juneau's whale-watching industry, but expressed concerns for the vessel crowding and the welfare of humpback whales in this area. This project combines multiple scientific disciplines to tackle the initial steps necessary in understanding the complex interaction between humans and humpback whales near Juneau, and in making management decisions that ensure a sustainable future for Juneau's humpback whales and the whale-watching industry that relies on them.
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Toothed whale interactions with longline fisheries in AlaskaPeterson, Megan J.; Carothers, Courtney; Mueter, Franz; Matkin, Craig; Criddle, Keith (2014-05)Killer whale (Orcinus orca) and sperm whale (Physeter macrocephalus) depredation occurs when whales damage or remove fish caught on longline gear. This project used a mixed methods approach incorporating Generalized Linear and Additive Modeling techniques and social research methods, such as semi-directed interviews and written questionnaires, to evaluate: 1) spatio-temporal depredation trends, 2) depredation effects on groundfish catch rates, and 3) socio-economic implications of depredation avoidance and changing fishing practices due to whale interactions. The occurrence of killer whale depredation varied by target species and area based on National Marine Fisheries Service longline survey data and observer commercial fishery data collected from 1998 to 2012 in the Bering Sea, Aleutian Islands, and Western Gulf of Alaska. The percentage of commercial fishery sets affected by killer whales was highest in Bering Sea fisheries for: sablefish (Anoplopomafimbria; 21.4%), Greenland turbot (Reinhardtius hippoglossoides; 9.9%), and Pacific halibut (Hippogolossus stenolepis; 6.9%). Killer whale depredation was more common on the standardized longline survey (9.2-34.6% skates impacted) than the commercial sablefish fishery (1.0-21.4% sets impacted) in all three management areas. Catch reductions were consistent across data sets. Average commercial fleet catch reductions ranged from 35-69% for sablefish, Pacific halibut and Greenland turbot (p<0.001); survey catch reductions ranged from 51-73% (p<0.001). Sablefish catch per unit effort, gear haul time and location significantly impacted the proportion of sets depredated. Fishermen reported changing their fishing practices in response to depredating whales by soaking gear longer to "wait the whales out" or moving to different fishing sites. These avoidance measures resulted in increased operation costs and opportunity costs in lost time. In a follow-up analysis based on data collected by fishermen in 2011 and 2012, it was found that killer whale depredation avoidance measures resulted in an average additional cost of $494 per vessel-day for fuel and crew food. Opportunity costs of time lost by fishermen averaged $486 per additional vessel-day on the grounds. These results provide insight into the potential impacts of whale depredation on fish stock abundance indices and commercially important fisheries in Alaska and will inform future research on apex predator-fisheries interactions.