Gray Whale Ecology and Conservation

This project aims to address the recent decline in Eastern North Pacific gray whales by examining their novel foraging strategies and energetic demands.

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Background

Gray whales have experienced major population declines over the past decade, with widespread reports of poor body condition and elevated mortality. These whales complete one of the longest mammalian migrations on Earth, and rely on the energy they acquire on high latitude feeding grounds to sustain their multi-month fasting period in the breeding lagoons of Baja California where they calve and nurse young. Understanding how gray whales acquire, store, and expend energy across both feeding and breeding grounds is critical for interpreting recent declines.

Amidst these declines, unusually large numbers of gray whales have begun arriving in Sitka Sound, Southeast Alaska, each spring to forage on Pacific herring eggs, revealing a largely novel and potentially energetically important strategy with implications for local prey dynamics and whale health. Since 2023, the Alaska Whale Foundation has led a community-informed research program to study this phenomenon, working closely with community collaborators and with support from the National Geographic Society. The program integrates vessel surveys, drone-based photogrammetry, and biologging tag deployments to examine population dynamics, foraging behavior, and energetics in this emerging foraging hotspot. As part of this program, Ph.D. student Liah McPherson's research focuses on quantifying gray whale abundance, distribution, body condition, and foraging ecology in Sitka Sound.

In Laguna San Ignacio, one of the gray whales’ sheltered breeding lagoons along the western coast of Baja California, MMRP is working with Gray Whale Research in Mexico to understand gray whale baseline physiology and behavior. We deploy biologging tags on gray whales to estimate their energetic requirements during this fasting period. Using these data alongside drone-based morphometric measurements, daily energetic expenditure can be estimated across body sizes, age classes, and behavioral states.

Together, these efforts provide important context for assessing gray whale health, interpreting population change, and understanding how whales are adapting to shifting environmental conditions, while supporting management decisions grounded in ecosystem and community stewardship.