Humpback whales and humans: a multi-disciplinary approach to exploring the whale-watching industry in Juneau, Alaska

Abstract

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.