동대만 잘피밭에 출현하는 해마와 산호해마의 출현량, 식성, 산란 비교

Abstract

Seasonal occurrence pattern, feeding habits and spawning between Hippocampus coronatus and Hippocampus mohnikei were studied in the eelgrass bed (Zostera marina) of Dongdae Bay, Korea from September 2006 to August 2007. A total of 284 Hippocampus coronatus (164) and Hippocampus mohnikei (120) were collected from September 2006 to August 2007. Particularly higher numbers of H. mohnikei were collected in April 2007 and August 2007, however, those of H. coronatus in September 2006. The size of H. coronatus ranged from 2.41 to 9.32 cm in height, and smaller individuals (< 5 cm in height) occurred more frequently higher in September 2006, December 2006, and from June to August 2007. For H. mohnikei, the size ranged from 4.23 to 9.59 cm in height, and smaller individuals occurred more frequently in June 2007 and July 2007. These two species were carnivores which consumed mainly amphipods and copepods. Its diets also included a small amount ofascothoracids, tanaidaceans, mysids, and cumaceans. Amphipods were the most important prey organisms to all size classes of these two species except for smaller individuals which exclusively fed copepods. While the dietary breadth of H. coronatus increased with increasing fish size, those of H. monikei were decreased. The gonadosomatic index (GSI) of the female of H. coronatus varied from 2.79 in December 2006 to 8.53 in September 2006, but that of H. mohnikei varied from 0.61 in April 2007 to 9.92 in September 2006. The spawning season of H. coronatus was from June to October, and that of H. mohnikei was from June to September during the study period. The fecundity of females was better correlated with body weight (BW) than height (Ht). However, the number of larvae in pouch of males was not correlated with body weight (BW) and height (Ht).