Overfishing and the ecological impacts of extirpating large parrotfish from Caribbean coral reefs
Overfishing and the ecological impacts of extirpating large parrotfish from Caribbean coral reefs
复制标题
过度捕捞和从加勒比珊瑚礁灭绝大型鹦嘴鱼的生态影响
DOI：
10.1002/ecm.1403
复制
发表时间：
2020
影响因子：
6.1
通讯作者：
D. Burkepile
中科院分区：
文献类型：
--
作者：
A. A. Shantz;Mark C. Ladd;D. Burkepile
大型动物的独特特征通常使它们能够在生态系统中发挥小型动物无法发挥的功能作用。然而，大型动物也面临着人类活动的更大风险。因此，了解大型动物的消失如何影响生态系统功能至关重要。在海洋中，对大型动物的选择性捕捞改变了许多物种的人口统计和大小结构。虽然失去大型动物对整个社区的影响是陆地研究的一个主要主题，但从海洋生态系统中移除大型动物的生态后果仍然没有得到充分研究。在这里，我们结合联合收割机调查数据，从282个地点在加勒比地区的实地实验，调查如何改变鹦嘴鱼种群的大小结构影响珊瑚礁群落。我们发现，加勒比海范围内的鹦嘴鱼种群倾向于较小的个体，长度<11厘米的鱼类占捕捞量最大地区种群的近70%，而在捕捞量最小的地区约为25%。尽管这些差异的大小结构，网站有相似的整体鹦嘴鱼生物量。因此，藻类覆盖与鹦嘴鱼生物量无关，而是与大型鹦嘴鱼的密度呈负相关。为了从机制上探讨大型鹦嘴鱼如何塑造底栖生物群落，我们操纵了鱼类对底栖生物的访问，以创建三个不同大小结构的鱼类群落。我们发现，排除大型或大中型鹦嘴鱼并没有改变整体鹦嘴鱼的放牧率，但导致藻类生物量分别增加了4倍和10倍。出乎意料的是，分支珊瑚受益于排除大型鹦嘴鱼，而土堆珊瑚物种的增长受到损害。同样，去除大型鹦嘴鱼导致意外增加珊瑚招聘时，没有大型和中型鱼类被排除在外。我们的数据突出了大型鹦嘴鱼在驱动珊瑚礁底栖动态方面的独特作用，并表明大小多样性是草食动物多样性如何影响珊瑚礁生态系统功能的重要组成部分。这项研究增加了越来越多的文献，揭示了从生态系统中去除大型动物的生态后果，并揭示了如何降低鹦嘴鱼种群的大小结构，改变功能多样性，重塑底栖珊瑚礁群落。
The unique traits of large animals often allow them to fulfill functional roles in ecosystems that small animals cannot. However, large animals are also at greater risk from human activities. Thus, it is critical to understand how losing large animals impacts ecosystem function. In the oceans, selective fishing for large animals alters the demographics and size structure of numerous species. While the community‐wide impacts of losing large animals are a major theme in terrestrial research, the ecological consequences of removing large animals from marine ecosystems remain understudied. Here, we combine survey data from 282 sites across the Caribbean with a field experiment to investigate how altering the size structure of parrotfish populations impacts coral reef communities. We show that Caribbean‐wide, parrotfish populations are skewed toward smaller individuals, with fishes <11 cm in length comprising nearly 70% of the population in the most heavily fished locations vs. ~25% at minimally fished sites. Despite these differences in size structure, sites had similar overall parrotfish biomass. As a result, algal cover was unrelated to parrotfish biomass and instead, was negatively correlated with the density of large parrotfishes. To mechanistically explore how large parrotfishes shape benthic communities, we manipulated fishes’ access to the benthos to create three distinct fish communities with different size structure. We found that excluding large or large and medium‐sized parrotfishes did not alter overall parrotfish grazing rates but caused respective 4‐ and 10‐fold increases in algal biomass. Unexpectedly, branching corals benefited from excluding large parrotfishes whereas the growth of mounding coral species was impaired. Similarly, removing large parrotfishes led to unexpected increases in coral recruitment that were absent when both large and medium bodied fishes were excluded. Our data highlight the unique roles of large parrotfishes in driving benthic dynamics on coral reefs and suggests that diversity of size is an important component of how herbivore diversity impacts ecosystem function on reefs. This study adds to a growing body of literature revealing the ecological ramifications of removing large animals from ecosystems and sheds new light on how fishing down the size structure of parrotfish populations alters functional diversity to reshape benthic reef communities.
影响因子：
4.6
作者：
Holbrook SJ;Schmitt RJ;Adam TC;Brooks AJ
通讯作者：
Brooks AJ
DOI：
10.1073/pnas.1812412116
发表时间：
2019-02-11
影响因子：
11.1
作者：
Schmitt RJ;Holbrook SJ;Davis SL;Brooks AJ;Adam TC
通讯作者：
Adam TC