Instituto de Investigaciones Marinas y Costeras (IIMyC), FCEyN, Universidad Nacional de Mar del Plata-CONICET, CC1260, (7600), Mar del Plata, Provincia de Buenos Aires, Argentina.
Instituto de Investigaciones Marinas y Costeras (IIMyC), FCEyN, Universidad Nacional de Mar del Plata-CONICET, CC1260, (7600), Mar del Plata, Provincia de Buenos Aires, Argentina.
Mar Environ Res. 2021 May;167:105285. doi: 10.1016/j.marenvres.2021.105285. Epub 2021 Feb 20.
Artificial light at night (ALAN) has the potential to alter ecological processes such as the natural dynamics of predator-prey interactions. Although understanding of ALAN effect on faunal groups has increased in recent years, few studies have explicitly tested for direct consequences of ALAN on predator-prey systems. Here, we evaluated the effect of ALAN on juvenile mortality due to cannibalism and general predation of the South American intertidal burrowing crab Neohelice granulata, a key ecosystem engineer of salt marshes. For this, we conducted tethering and crab enclosure experiments for both night and day periods during successive tidal floods in a semidiurnal tidal regime. Both experimental approaches were deployed simultaneously in the field and they lasted four consecutive days during new moon nights. ALAN was simulated by a white LED lamp (30W) with a solar panel as a source of power in five separated areas selected as replicates. For general predation, juvenile survival under ALAN was 44% lower than during the daytime and 61% lower than under natural dark conditions. For cannibalism, juvenile survival under ALAN and during the daytime was similar and about 30% lower than under natural dark conditions. We also found that the abundance of adult male crabs (cannibals) under ALAN was nearly five times higher than at natural dark conditions. Our field experiments provide evidence that ALAN can increase the mortality of juvenile crabs and is at least partially driven by cannibalistic interactions.
夜间人工光 (ALAN) 有可能改变生态过程，例如捕食者-猎物相互作用的自然动态。尽管近年来人们对 ALAN 对动物群的影响有了更多的了解，但很少有研究明确测试 ALAN 对捕食者-猎物系统的直接影响。在这里，我们评估了 ALAN 对南美潮间带穴居蟹 Neohelice granulata 幼体因同类相食和一般捕食而导致的死亡率的影响，这种蟹是盐沼生态系统的关键生态工程师。为此，我们在半每日潮汐期间进行了连续潮汐洪水期间的夜间和白天的系泊和螃蟹围栏实验。这两种实验方法同时在野外进行，并在新月之夜持续了四天。ALAN 通过一个带有太阳能电池板的白色 LED 灯（30W）模拟，作为五个独立区域的电源，这些区域被选为重复区域。对于一般捕食，在 ALAN 下的幼体存活率比白天低 44%，比自然黑暗条件下低 61%。对于同类相食，在 ALAN 下和白天的幼体存活率相似，比自然黑暗条件下低约 30%。我们还发现，在 ALAN 下成年雄性螃蟹（捕食者）的丰度几乎是自然黑暗条件下的五倍。我们的野外实验提供了证据表明，ALAN 可以增加幼蟹的死亡率，并且至少部分是由同类相食的相互作用驱动的。
