INTERANNUAL VARIABILITY IN MORPHOMETRIC CONDITION OF LARVAL FISH AS A FUNCTION OF ENVIRONMENTAL VARIABLES IN BEAUFORT, NC

Abstract

Recruitment can vary by several orders of magnitude and can be unpredictable from year-to-year, with its variability influenced by oceanic conditions experienced by fish larvae. Variations in larval abundance and condition have not been consistently related to juvenile abundance and recruitment for many fisheries species. By studying how environmental factors affect larval fish condition, we may be able to better anticipate when a high or low recruitment year occurs since condition affects larval fish growth and survival. This project aims to expand our understanding of the relationship between morphometric condition, environmental conditions, and prey abundance among four North Carolinian fishes: Atlantic Croaker (Micropogonias undulatus), Mojarra (Eucinostomus sp.), White Mullet (Mugil curema), and Broad Striped Anchovy (Anchoa hepsetus). All species had some aspect of their morphometric condition influenced by an environmental or ecological variable. Temperature and density dependent effects were fairly widespread, affecting the condition of 3 out of 4 species. Zooplankton effects were less widespread, affecting 2 out of 4 species. Interactions between temperature and zooplankton, while individually important, were less widespread, affecting only one species. The relationship between environmental variables and morphometric condition can lead to insight about the species dynamics that was not previously known. Future findings like these can lead to the development of better recruitment models.