Population dynamics and disease-linked host use of the sea urchin symbiont Dactylopleustes yoshimurai (Crustacea: Amphipoda: Pleustidae) on Strongylocentrotus intermedius
Abstract
Dactylopleustes yoshimurai is an echinoid-associated amphipod that frequently aggregates on disease lesions of the short-spined sea urchin Strongylocentrotus intermedius in Otsuchi Bay, northeastern Japan. However, its life history and use of diseased hosts remain poorly understood. We combined four years of monthly SCUBA surveys (from January 2020 to January 2024) with quantitative sampling of diseased and healthy sea urchins (from January 2021 to January 2024) to examine how host disease status structures the population dynamics of D. yoshimurai. The amphipod occurred on ～10–80% of sea urchins and was consistently more frequent and much denser on diseased than on healthy hosts, with winter peaks that broadly coincided with maxima in disease prevalence. Size–frequency distributions on diseased sea urchins were strongly dominated by juveniles (
Fields of Study & Subjects
Marine and coastal plant biology
Marine Biology and Ecology Research
Marine Biology and Environmental Chemistry
Publication details
- Journal / source
- Crustacean Research
- Publisher
- Carcinological Society of Japan
- Volume
- 55
- Issue
- 0
- Pages
- 45–60
- Publication date
- 28 July 2026
- Language
- EN