# Harnessing Population Genomics, Gut Microbiota, and Environmental DNA Surveillance for the Conservation of Chinese Spotted Seals in a Changing World

## TL;DR

This paper reviews how genomics, gut microbiota, and environmental DNA can help conserve Chinese spotted seals, which are facing threats from environmental changes.

## Contribution

The paper systematically reviews molecular research and proposes the use of eDNA technology for improved conservation strategies.

## Key findings

- Chinese spotted seal populations exhibit low genetic diversity based on molecular marker studies.
- Recent omics technologies have enabled detailed studies of the species' genomic and gut microbiota profiles.
- Environmental DNA technology is suggested as a promising tool for future population monitoring and conservation.

## Abstract

The triple planetary crisis—encompassing climate change, biodiversity loss, and pollution—poses escalating threats to Earth's systems, particularly impacting marine mammals. The spotted seal (
Phoca largha
Pallas 1811), currently recognized as the only pinniped species known to breed in China, holds the status of a National Grade I protected species in China. To elucidate the genetic diversity of Chinese spotted seal populations and provide scientific foundations for their conservation and management, this review systematically summarized the fundamental biological characteristics and documented migration routes of spotted seal populations in China, with particular emphasis on reviewing molecular‐level research advancements regarding population genetic structure. Early studies primarily employed molecular markers such as microsatellite DNA and mitochondrial DNA (mtDNA), revealing relatively low genetic diversity levels within Chinese spotted seal populations. In recent years, rapid developments in omics technologies have enabled comprehensive investigations into both genomic compositions, as well as gut microbial community diversity and functional profiles of this species. Furthermore, this review critically examined current research limitations and challenges while proposing the potential advantages and developmental trends of environmental DNA (eDNA) technology in future population studies. These technological and strategic advancements are anticipated to significantly enhance survey efficiency and conservation effectiveness for Chinese spotted seal populations.

Marine mammals are sentinel species for ocean and human health. Multiple anthropogenic and environmental stressors threaten these organisms, particularly China's spotted seals, which have experienced significant decline over the past half‐century. Our review reveals low genetic diversity in Chinese spotted seal populations. Recent gut microbiota studies are vigorously pursued, revealing close host‐microbiota‐health interlinks. This synthesis examines current research limitations while proposing environmental DNA technology's advantages and developmental trends for future studies.