The Antarctic spiny plunderfish Harpagiferantarcticus is a common species distributed along thesouthern Scotia Arc, representing one of the most importantcomponents of the littoral benthic fish communitythere. Compared to adulthood, the early life history traits ofH. antarcticus are poorly known, especially for the populationinhabiting the shallow waters off the South ShetlandIslands. Through the analysis of sagittal otolith microstructure,we estimated age and growth from early larvae collectedduring the austral summer at Chile Bay, GreenwichIsland. An exponential model fitted to the age-length dataprovided estimates of hatching size and mean larval growthof the local population, being, respectively, 5.36 mm and0.17 mm day-1 (range 0.12-0.22 mm day-1), correspondingto a daily percentage increase in body size of 2.2%.Back-calculated hatch dates were positively correlated towind intensity, especially in case of northeast wind dominance.Based on this evidence, we suggest that hatching ofH. antarcticus might be triggered by wind-induced turbulencein nearshore subtidal environments of the South ShetlandIslands. From an ecological perspective, the early lifehistory strategy of this species consisted of a spring-summerhatching of small, fast-growing larvae, which developinto a demersal juvenile stage before their first winter oflife.
Early life history traits of Harpagifer antarcticus (Harpagiferidae, Notothenioidei) from the South Shetland Islands during austral summer
La Mesa Mario;
2017
Abstract
The Antarctic spiny plunderfish Harpagiferantarcticus is a common species distributed along thesouthern Scotia Arc, representing one of the most importantcomponents of the littoral benthic fish communitythere. Compared to adulthood, the early life history traits ofH. antarcticus are poorly known, especially for the populationinhabiting the shallow waters off the South ShetlandIslands. Through the analysis of sagittal otolith microstructure,we estimated age and growth from early larvae collectedduring the austral summer at Chile Bay, GreenwichIsland. An exponential model fitted to the age-length dataprovided estimates of hatching size and mean larval growthof the local population, being, respectively, 5.36 mm and0.17 mm day-1 (range 0.12-0.22 mm day-1), correspondingto a daily percentage increase in body size of 2.2%.Back-calculated hatch dates were positively correlated towind intensity, especially in case of northeast wind dominance.Based on this evidence, we suggest that hatching ofH. antarcticus might be triggered by wind-induced turbulencein nearshore subtidal environments of the South ShetlandIslands. From an ecological perspective, the early lifehistory strategy of this species consisted of a spring-summerhatching of small, fast-growing larvae, which developinto a demersal juvenile stage before their first winter oflife.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
