The role of Asterina stellifera (Echinodermata: Asteroidea) as a predator in a rocky intertidal community in southern Brazil
The role of Asterina stellifera (Echinodermata: Asteroidea) as a predator in a rocky intertidal community in southern Brazil
复制标题
巴西南部岩石潮间带群落中 Asterina stellifera（棘皮动物：Asteroidea）作为捕食者的作用
DOI：
--
复制
发表时间：
2009
期刊：
影响因子：
--
通讯作者：
J. Roper
中科院分区：
文献类型：
--
作者：
P. Calil;R. Rocha;C. A. Freire;J. Roper
巴西南部的Asterina stellifera Mobius， 1859年的种群数量正在下降，如今该物种已被列入巴西濒危物种名单。本文通过增加星蚜密度的实验研究了星蚜作为捕食者对石质底栖群落的生态作用。从附近其他地点捕获的海星被添加到三个重复的地块中，每隔15天保持它们的密度。在结壳群落中确定的32种物种中，没有一种似乎受到实验的影响。两种藤壶Chthamalus bisinuatus Pilsbry（1916）和藻类Gracilaria verrucosa （Hudson）对捕食表现出很小的明显反应。我们发现，即使在高密度的情况下，星蚜对群落的捕食压力也很弱。这一结果与在北半球和澳大利亚观察到的类似物种截然不同。
Populations of Asterina stellifera Mobius, 1859 are declining in southern Brazil and today the species is on the Brazilian list of endangered species. Here we experimentally investigate the ecological role played by A. stellifera as a predator on the rocky substrate community by increasing densities of this species. Starfish taken from other, nearby, locations were added to three replicate plots and their density was maintained every 15 days. None of the total of 32 species that were identified in the encrusting community appeared to be influenced by the experiment. Two species, the barnacle Chthamalus bisinuatus Pilsbry, 1916 and the algae Gracilaria verrucosa (Hudson), showed small apparent responses to predation. We found that A. stellifera only exerts weak predation pressure on the community, even at high densities. This result is strikingly different from that observed for similar species in the northern hemisphere and in Australia.