Abstract:
This study explored the habitat suitability of mullet
Liza haematocheila ichthyoplankton (eggs, larvae and juveniles) in the coastal waters of the Yellow River Estuary. The ichthyoplankton were investigated by horizontal tows. Water depth, sea surface salinity (SSS), chlorophyll-
a (Chl
a) concentration and dissolved oxygen were collected at each survey station. Sea surface temperature (SST) and offshore distance were obtained by remote sensing. First, generalized additive model (GAM) was used to select optimal environmental factors and determine their weights. Then, the habitat suitability index (
HSI) was established by the weighted average method. The results indicated that SST, Chl
a concentration, SSS and water depth were the key factors affecting the distribution of mullet ichthyoplankton according to the fitting accuracy of GAM, and their weights were 0.6838, 0.2043, 0.0754 and 0.0365 in the
HSI model. The spatial distribution of the most suitable habitat for mullet ichthyoplankton obviously differed in April and May. In April, the most suitable habitat was located in Laizhou Bay, followed by the Yellow River Estuary waters and the scattered areas in the north of the estuary. In May, however, the most suitable habitat was mainly distributed in the estuary waters of the Yellow River, followed by Laizhou Bay, and the area of suitable habitat was greatly reduced. Spatial distribution of the most suitable habitat for mullet ichthyoplankton was closely related to the development stage of the fish, ecological habits and environmental factors in the coastal waters of the Yellow River Estuary. This study provided basic data for habitat protection and restoration of mullet.