types of spawning stock

例句：

1. 1. The fish farm is a major source of spawning stock for the local ecosystem.
   这个养鱼场是当地生态系统的主要繁殖鱼种来源。
2. 2.The conservationists are working to preserve the spawning stock of the endangered species.
   保护主义者正在努力保护这种濒危物种的繁殖鱼种。
3. 3.The fisherman relies on the spawning stock from the nearby river to sustain his livelihood.
   渔民依靠附近的河流提供的繁殖鱼种来维持生计。