sweet

栃木県の小山で鮎釣りが解禁されました。sweetには「腕のいい，上手な」（『プログレッシブ英和中辞典』小学館）という意味があり，sweet artは「妙技」と解釈できます。また，記事にもあるように「鮎」は英語でsweetfishといい，見出しはそれを意識したものです。（Koyamamoto）

Sweet art of angling
Anglers enjoy fishing for ayu, or sweetfish, in the Omoigawa river in Oyama, Tochigi Prefecture, on Sunday, after the ayu fishing season opened on this river, the first in the Kanto region. According to the local Shimotsuga fishery cooperative, about 180,000 young ayu were released in the river in April and May. As water temperatures have been higher than in usual years, the ayu grew to 15-17 centimeters--larger than normal--and the catch was good, the cooperative said.
http://the-japan-news.com/news/article/0000241866