Field measurements reveal exposure risk to microplastic ingestion by filter-feeding megafauna

Abstract

Microparticles, such as microplastics and microfibers, are ubiquitous in marine food webs. Filter-feeding megafauna may be at extreme risk of exposure to microplastics, but neither the amount nor pathway of microplastic ingestion are well understood. Here, we combine depth-integrated microplastic data from the California Current Ecosystem with high-resolution foraging measurements from 191 tag deployments on blue, fin, and humpback whales to quantify plastic ingestion rates and routes of exposure. We find that baleen whales predominantly feed at depths of 50–250 m, coinciding with the highest measured microplastic concentrations in the pelagic ecosystem. Nearly all (99%) microplastic ingestion is predicted to occur via trophic transfer. We predict that fish-feeding whales are less exposed to microplastic ingestion than krill-feeding whales. Per day, a krill-obligate blue whale may ingest 10 million pieces of microplastic, while a fish-feeding humpback whale likely ingests 200,000 pieces of microplastic. For species struggling to recover from historical whaling alongside other anthropogenic pressures, our findings suggest that the cumulative impacts of multiple stressors require further attention.

Document Details

Document Type
Pub Defense Publication
Publication Date
Nov 01, 2022
Source ID
10.1038/s41467-022-33334-5

Entities

People

  • A. S. Friedlaender
  • Elliott L. Hazen
  • J. Calambokidis
  • James A. Fahlbusch
  • Jeremy A. Goldbogen
  • M. S. Savoca
  • Max Czapanskiy
  • Shirel R. Kahane-Rapport

Organizations

  • National Science Foundation
  • Office of Naval Research
  • United States Department of Defense

Tags

Fields of Study

  • Environmental science

Readers

  • Aquatic Ecology
  • Educational Psychology
  • Marine Mammal Biology