By the next morning, these fish are headed home, Adams points out. They leave behind millions of fertilized, drifting eggs and begin a two-month larval stage that scientists hope will result in a new baby bonefish settlement somewhere nearby to begin the cycle over again.
It was a 2011 study published by UMass Amherst's Danylchuk, an expert on coastal fish stocks, angling impact and how to protect ecosystems, that first reported on 30 sonically-tagged bonefish observed over two years as they moved into deep water to spawn at night off Eleuthera in the Bahamas. But more details were needed about such behavior as gulping air and bumping each other, he says. Hence this new study, which looked at more detail and provides a wealth of new information he hopes to publish soon.
In particular, Danylchuk says, the recent work highlights the critical importance of protecting bonefish spawning aggregations. "This new understanding of bonefish movement and spawning aggregations has significant implications for their conservation," he says, because it establishes that pre-spawning aggregation sites are located in transition areas between shallow coastal habitats and deep ocean waters, the very same places that humans find desirable for marinas and tourism development.
Adams adds that because bonefish typically live in small, shallow-water home ranges most of the year, conservation strategies have previously focused only there. But now researchers have determined that the fish migrate long distances to gather in large schools in identifiable spawning regions, then move offshore to very deep water. He and his co-authors say this spawning migration requires a much-expanded conservation outlook that links
|Contact: Janet Lathrop|
University of Massachusetts at Amherst