Distribution and relative abundance of flyingfish (Exocoetidae) in the eastern Caribbean. II. Spawning substrata, eggs and larvae

• Published in: Marine ecology. Progress series (Halstenbek) Vol. 117; no. 1/3; pp. 25 - 37
• Main Authors: Hunte, Wayne, Oxenford, Hazel A., Mahon, Robin
• Format: Journal Article
• Language: English
• Published: Inter-Research 1995
• Subjects: Ecological life histories; Eggs; Exocoetidae; Fish; Fish eggs; Fish larvae; Larvae; Larval development; Marine fishes; Night tables; Salinity
• ISSN: 0171-8630; 1616-1599
• DOI: 10.3354/meps117025

We investigated the distribution and relative abundance of flyingfish spawning substrata (flotsam), eggs and larvae by neuston tows at 40 stations across a 67 500 square nautical mile (nmi²) area of the eastern Caribbean from April 10 to May 6, 1988. Flotsam occurred in only 48% of the tows and in quantities < 1 g nmi⁻¹ tow. Non-buoyant flyingfish eggs characteristic of Hirundichthys affinis, Parexocoetus brachypterus and Cypselurus cyanopterus were virtually absent. Although 21 % of the 3014 fish eggs collected were flyingfish eggs, all but 3 of these were pelagic eggs characteristic of Exocoetus spp. The rarity of eggs and flotsam suggests that flyingfish may typically spawn on floating material until it submerges, and/or spawn on submerged substrata. Catch rates of all fish larvae and of flyingfish larvae were significantly higher in day tows than night tows, and mean larval size was larger by night. This indicates that larvae, and particularly smaller larvae, may move downwards at night. This may be a light response, since P. brachypterus larvae were more abundant at the surface around full moon than new moon. Larval abundance varied significantly across the survey area for all flyingfish, and separately for E. volitans, P. brachypterus and C. cyanopterus. Small larvae of E. volitans were more abundant at oceanic than coastal stations. The reverse was true for P. brachypterus, indicating different spawning locations for these species. The geographical distribution of larvae of C. cyanopterus coincided with the adult distribution, both larvae and adults being rare in the southwest sector of the survey area near the South American mainland. Larvae of H. affinis were relatively rare. This rarity, and the virtual absence of eggs, is surprising given the abundance of this species in the eastern Caribbean and the fact that H. affinis was known to be spawning during the time of the survey. The depth at which H. affinis typically spawns and hatches requires further investigation.