Masello Juan F, Kato Akiko, Sommerfeld Julia, Mattern Thomas, Quillfeldt Petra
Department of Animal Ecology & Systematics, Justus Liebig University Giessen, Heinrich-Buff-Ring 26, D-35392 Giessen, Germany.
Centre d'Etudes Biologiques de Chizé, UMR7372 CNRS-Université La Rochelle, 79360 Villiers en Bois, France.
Front Zool. 2017 Jul 5;14:33. doi: 10.1186/s12983-017-0219-8. eCollection 2017.
Foraging efficiency determines whether animals will be able to raise healthy broods, maintain their own condition, avoid predators and ultimately increase their fitness. Using accelerometers and GPS loggers, features of the habitat and the way animals deal with variable conditions can be translated into energetic costs of movement, which, in turn, can be translated to energy landscapes.We investigated energy landscapes in Gentoo Penguins from two colonies at New Island, Falkland/Malvinas Islands.
In our study, the marine areas used by the penguins, parameters of dive depth and the proportion of pelagic and benthic dives varied both between years and colonies. As a consequence, the energy landscapes also varied between the years, and we discuss how this was related to differences in food availability, which were also reflected in differences in carbon and nitrogen stable isotope values and isotopic niche metrics. In the second year, the energy landscape was characterized by lower foraging costs per energy gain, and breeding success was also higher in this year. Additionally, an area around three South American Fur Seal colonies was never used.
These results confirm that energy landscapes vary in time and that the seabirds forage in areas of the energy landscapes that result in minimized energetic costs. Thus, our results support the view of energy landscapes and fear of predation as mechanisms underlying animal foraging behaviour. Furthermore, we show that energy landscapes are useful in linking energy gain and variable energy costs of foraging to breeding success.
觅食效率决定了动物是否能够养育健康的幼雏、维持自身状态、躲避捕食者并最终提高其适合度。通过使用加速度计和全球定位系统记录器，栖息地的特征以及动物应对多变环境的方式可以转化为运动的能量消耗，进而可以转化为能量景观。我们研究了福克兰/马尔维纳斯群岛新岛两个企鹅聚居地的巴布亚企鹅的能量景观。
在我们的研究中，企鹅使用的海洋区域、潜水深度参数以及远洋和底栖潜水的比例在年份和聚居地之间均有所不同。因此，能量景观在不同年份之间也有所变化，我们讨论了这与食物可利用性差异之间的关系，食物可利用性差异也反映在碳和氮稳定同位素值以及同位素生态位指标的差异上。在第二年，能量景观的特征是每获得单位能量的觅食成本较低，并且该年的繁殖成功率也较高。此外，三个南美海狗聚居地周围的一个区域从未被使用过。
这些结果证实能量景观随时间变化，并且海鸟在能量景观中导致能量消耗最小化的区域觅食。因此，我们的结果支持能量景观和对捕食的恐惧是动物觅食行为潜在机制的观点。此外，我们表明能量景观有助于将觅食的能量获取和可变能量成本与繁殖成功率联系起来。
