Changes in marine environments affect fishery resources at different spatial and temporal scales in marine ecosystems. Predictions from species distribution models are available to parameterize the environmental characteristics that influence the biology, range, and habitats of the species of interest. This study used generalized additive models (GAMs) fitted to two spatiotemporal fishery data sources, namely 1 • spatial grid and observer record longline fishery data from 2006 to 2010, to investigate the relationship between catch rates of yellowfin tuna and oceanographic conditions by using multispectral satellite images and to develop a habitat preference model. The results revealed that the cumulative deviances obtained using the selected GAMs were 33.6% and 16.5% in the 1 • spatial grid and observer record data, respectively. The environmental factors in the study were significant in the selected GAMs, and sea surface temperature explained the highest deviance. The results suggest that areas with a higher sea surface temperature, a sea surface height anomaly of approximately −10.0 to 20 cm, and a chlorophyll-a concentration of approximately 0.05-0.25 mg/m 3 yield higher catch rates of yellowfin tuna. The 1 • spatial grid data had higher cumulative deviances, and the predicted relative catch rates also exhibited a high correlation with observed catch rates. However, the maps of observer record data showed the high-quality spatial resolutions of the predicted relative catch rates in the close-view maps. Thus, these results suggest that models of catch rates of the 1 • spatial grid data that incorporate relevant environmental variables can be used to infer possible responses in the distribution of highly migratory species, and the observer record data can be used to detect subtle changes in the target fishing grounds.

We used sat el lite-de rived sea sur face tem per a ture (SST) data for the win ters of 1996 -2008 to ex am ine the ex cep tional in tru sion of China Coastal Cur rent into the Tai wan Strait. The long term ob ser va tion re veals that, in 1999 and 2000, the strong wind (> 6 m s -1 ) lasted for 12 and 16 days with a drop of 5.35 and 5.5°C in SST, re spec tively. The sat el lite data also showed that the China Coastal Cur rent in truded from the north of the Chang-Yuen Ridge into the wa ters sur round ing the Peng-Hu Is lands, with wind speeds of more than 6.7 m s -1 lasted for 30 days dur ing the same pe riod. The ex cep tional in tru sion re sulted in the min i mum SST of 12.6°C on 16 Feb ru ary 2008, 7.8°C lower than the 12-year av er age of Feb ru ary (20.4°C). The higher SST (> 18°C) ap peared af ter 21 Feb ru ary 2008 in di cat ing the north ward with drawal of the cold wa ter. Dur ing the pe riod of 15 -21 Feb ru ary 2008, the China Coastal Cur rent in truded to as far south as the water around Peng-Hu Islands.To com pare the El Niño/La Niña events with re gard to SST and wind speed, we found that SST was warmer in the El Niño

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Based upon long-term observations (1993 -2010) of satellite-derived winter sea surface temperature (SST) data, an exceptional cold-water intrusion into the southern Taiwan Strait (TS) was noted in February 2008. In the winter of 2008, La Niña caused a strong and continuous northeasterly wind that drove the cold ocean current, the China Coastal Current, more southward to penetrate the southern TS north of the Chang-Yuen Ridge. A portion of this current turned eastward to the south of Penghu Islands (PHI). The low-SST event significantly impeded local marine aquaculture and wild fish, causing the death of more than 73 tons of fish around PHI. Comparing variations of the first quarterly catches in 2008 with the long-term averages from 1993 to 2010 (excluding 2008), we noted a 50 to 80% decrease in catches from pole-and-line, long-line, and gill-net fishery. Non-migratory species dominated the composition of the catches. We also noted a greater than 230% increase in the catches from set-net fishery, with the majority being migratory species. These results illustrate the positive and negative effects of cold-water intrusion on several fish communities and species.