Chasqui-Velasco Luis, Alvarado Ch Elvira, Acero Arturo, Zapata Fernando A
Parques Nacionales de Colombia, Territorial Suroccidente, Avenida 3G Norte 37-70, Call, Colombia.
Rev Biol Trop. 2007 Sep-Dec;55(3-4):825-37.
To examine the effects of herbivorous and corallivorous fishes on the survival of transplanted colonies of Montastraea annularis, Diploria labyrinthiformis and Porites astreoides, both transplanted and native colonies were full-cage enclosed and compared to open (uncaged) colonies, while caging effects were assessed with a partial-cage (roof treatment). To evaluate if transplant stress increased the corals availability to fish predation, comparisons of fish foraging intensity among transplanted versus native colonies were made. To determine the density of herbivorous and corallivorous fishes on the transplants area visual censuses were made. The transient herbivorous fishes (Scaridae and Acanthuridae) were the most abundant fishes, and the corallivorous fishes (mainly Chaetodontidae) were the scarcest. A negative effect of territorial herbivorous fishes on M annularis transplants survival was observed, mainly early on the study. Fish foraging intensity was similar on transplanted and native colonies, but differed among coral species, being lowest on D. labyrinthiformis. Fast macroalgal growth inside full-cages due to reduced fish grazing was observed. This caused partial bleaching and partial mortality in some colonies, mainly of P. astreoides. No significant difference in healthy tissue percentages among full-cage and uncaged colonies on M. annularis and D. labyrinthiformis was found, while in P. astreoides there were evilent differences. The results indicate a damselfish negative effect on transplants survival early on the study, which can change depending on the fish and coral species involved. Results also indicate a fish grazing positive effect, caused by the reduction of coral-algae competition pressure, mainly on P. astreoides. Parrotfishes seem to affect corals survival both negatively through direct biting, and positively by controlling algal growth. Overall, coral transplant success was almost unaffected by fish foraging activity although several differences among coral species were obvious in relation to colony shape. Additionally, the interaction among herbivorous fish grazing and coral-algae competition balance appear important in determining transplant survival.
为研究草食性鱼类和食珊瑚鱼类对环状蔷薇珊瑚、迷宫鹿角珊瑚和星状多孔珊瑚移植群体存活的影响,对移植群体和本地群体均进行全笼封闭,并与开放(无笼)群体进行比较,同时通过部分笼养(顶部处理)评估笼养效果。为评估移植应激是否增加了珊瑚对鱼类捕食的易感性,对移植群体和本地群体之间的鱼类觅食强度进行了比较。为确定移植区域草食性鱼类和食珊瑚鱼类的密度,进行了目视普查。临时草食性鱼类(鹦嘴鱼科和刺尾鱼科)是数量最多的鱼类,而食珊瑚鱼类(主要是蝴蝶鱼科)最为稀少。观察到领地性草食性鱼类对环状蔷薇珊瑚移植群体的存活有负面影响,主要在研究初期。移植群体和本地群体上的鱼类觅食强度相似,但在不同珊瑚种类间存在差异,在迷宫鹿角珊瑚上最低。观察到由于鱼类啃食减少,全笼内大型藻类生长迅速。这导致一些群体出现部分白化和部分死亡,主要是星状多孔珊瑚。在环状蔷薇珊瑚和迷宫鹿角珊瑚上,全笼和无笼群体的健康组织百分比没有显著差异,而在星状多孔珊瑚上则有明显差异。结果表明,在研究初期,雀鲷对移植群体的存活有负面影响,这种影响可能因所涉及的鱼类和珊瑚种类而异。结果还表明,鱼类啃食有积极作用,主要是通过降低珊瑚 - 藻类竞争压力,对星状多孔珊瑚影响较大。鹦鹉鱼似乎通过直接啃咬对珊瑚存活产生负面影响,同时通过控制藻类生长产生积极影响。总体而言,尽管不同珊瑚种类在群体形状方面存在明显差异,但珊瑚移植成功率几乎不受鱼类觅食活动的影响。此外,草食性鱼类啃食与珊瑚 - 藻类竞争平衡之间的相互作用在决定移植存活方面似乎很重要。