Presence of bonefish leptocephali in estuarine habitats on Oʻahu

Bonefishes and other elopomorphs have a unique, transparent leptocephalus larval stage that is challenging to study due to its cryptic nature. Understanding life history is important especially considering adult bonefishes in Hawaiʻi are highly sought gamefish valued for their tenacious fight on rod-and-reel and delicate taste. In this study light traps were used to capture leptocephali at three nearshore locations around Oʻahu, Hawaiʻi. Across 130 + h of trapping, 59 larvae were captured, most during 2000–2100 h on rising tides. Lengths ranged from 54 to 66 mm, indicating late stage I larvae. Otolith analyses (N = 26) revealed ages from 28 to 72 days with an average age of about 48 days. Genetic species identification on a subset of the larvae showed that one of 28 total specimens was Albula virgata, which is endemic to Hawaiʻi, and the remaining were the Indo-Pacific A. glossodonta. Along with calm inshore waters, estuarine habitat appears to be a critical element for leptocephali recruitment success. Reducing impacts to these estuarine habitats and protecting and restoring freshwater input may have positive impacts on leptocephali recruitment, the essential starting point for thriving bonefish fisheries in Hawaiʻi.