內水面 가두리 養殖場의 그물에 每年 附着, 成長하여 물의 疏通을 抑制시킬 뿐 만 아니라, 飼育魚를 逮捕하거나 漁網交替時 綱에 附着한 이끼벌레와 接觸되므로서 魚類斃死狀態, 각종 藥劑에 의한 驅除實驗을 실시하였다. 1) 옥정호 가두리 漁綱에 附着된 이끼벌레는 分類上 태형동물문(Bryozoa), 암후강(Phylactolaemata)에 속하는 총담이끼벌레, Lophopodella carteri HYATT이다. 2) 群體의 크기는 0.8∼8.5×0.6∼5.0㎝이었다. 3) 水溫 25.7℃인 6月 下旬에 附着하기 시작하여 水溫 22℃때인 10月에 最大크기로 成長되고, 水溫 8.5℃ 12月 中旬에 群體는 收縮되면서 附着物에서 消失되어진다. 4) 表層에서 5m層까지 附着되나, 2∼3m層에 주로 附着한다. 5) 水溫 25℃때 이끼벌레와 1分間 接觸시킨 全長 4℃ 17㎝의 이스라엘 잉어 30마리와 3∼7㎝ 금붕어 30마리는 1時間 40分 經過 後 이스라엘잉어는 90%, 금붕어는 100% 斃死되었으나, 메기는 전혀 斃死하지 않았다. 6) 魚類에 被害를 주는 이끼벌레는 觸手周圍에 있는 刺胞에 의한 것으로 推定되며, 이 刺胞毒은 잉어, 금붕어에 猛毒性을 나타낸다. 7) Formalin 300ppm, 食鹽 5%, malachite green 5 ppm, KMnO₄200ppm, Kl 1000ppm, DDVP 10 ppm에 이끼벌레를 10分間 沈積시켰으나 전부 生存하였다.

In inland aquaculture, a lot of fishes often died cause of touch of L. carteri which is attached on the net cage. In this works, the experiment were carried out on classification of species, toxin test, and extermination with some chemicals. A bryozoa from net cage in lake Okjeong is classified into the Phylactolaemata, Lophopodella carteri Hyatt. A bryozoa broke out firstly on the 30th of June with water temperature up to 31℃ and it reattached on the net with water temperature below 30℃. Size of bryozoa colony is about 0.8×0.6∼1.7×1.5㎝. Water column of attachment was 0∼5m and the peak is 2∼3m. In toxin test on the israeli carp, goldfish and catfish touched with bryozoa for 1 minute at 25℃ of water temperature, a dead fish appeared at 20 minutes after touched. Mortality was 90% for israeli carp and 100% for goldfish at 100 minuties after touched, but catfish was not died at all. It was supposed that the toxin is from nematocyst being around tentacles and this toxin act a deadly poison on a israeli carp and goldfish. In extermination test, the bryozoa treated with 300ppm of formalin, 5 % of sodium chloride, 5ppm of malachite green, 200ppm of potassium permanganate, 1000ppm of potassium iodide, 10ppm of DDVP for minute respectively, all of them were not effected.