Impact of urbanization and anthropogenic food sources on the ecology and energy budgeting of the Eurasian red squirrel (Sciurus vulgaris)

城市化和人类食物来源对欧亚红松鼠（Sciurus vulgaris）生态和能源预算的影响

• 批准号: 409308009
• 负责人: Dr. Mathilde Cordellier
• 金额: --
• 依托单位: Abteilung Molekulare Evolutionsbiologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/409308009?language=en
• 关键词: Impact; urbanization; anthropogenic; food; sources

The goal of this study is to understand and quantify the impact of urbanization and anthropogenic food resources on the ecology and energy budgets of small synurbic mammals, which occur in higher densities in urban than natural habitats. Furthermore, we aim to determine whether these high population densities indicate that a species is thriving, or if the habitat is acting as an ecological trap containing inbred individuals. Therefore, we will contrast various ecological traits and the genetic diversity of populations of the Eurasian red squirrel (Sciurus vulgaris) inhabiting small patches of urban habitat with those living in natural areas. As high food availability seems to contribute to increased urban densities, we will investigate the influence of the abundance of natural and supplemented food resources. We expect that the latter is of high importance for urban wildlife and by conducting a citizen survey we will be able to quantify these food sources and their spatial and temporal distribution. We predict that squirrels in urban sites will have a stable body mass and condition throughout the year, even during the seasons of food scarcity (i.e. spring and summer), owing to high amounts of supplemented food. This will likely be in combination with more numerous reproductive individuals. However, it is plausible that we will also detect negative effects of urban inhabitation such as malnutrition, caused by an unbalanced diet, or high parasite loads, resulting from high inter-individual contact rates at artificial feeding sites. These negative effects could offset the aforementioned benefits and might illustrate a trade-off between the survival of populations and the health of individuals. Usable urban green patches might also exist as sink habitats; inbreeding detrimental to population health could occur owing to reduced movement opportunities in a highly urban matrix. Finally, to enable a complete picture of the interaction between diet and energy budgeting, we will perform a food choice experiment combined with measurements of energetic demands. This will help us to quantify the consequences of urbanization on metabolism and understand the energetic and nutrient constraints of different habitats. The results of this project will not only be of relevance to urban wildlife management and conservation practices, but also for the management of wild animal populations at natural sites. Animals are forced to use cities due the pressure of over-expanding urban habitats, but if cities symbolize sink-habitats species will still need the disappearing forests to survive. Understanding underlying mechanisms and developing appropriate actions to face these contradicting conditions is one of the main future challenges for nature conservation.

本研究的目的是了解和量化城市化和人为食物资源对小型城市哺乳动物的生态和能量预算的影响，这些哺乳动物在城市中的密度高于自然栖息地。此外，我们的目标是确定这些高人口密度是否表明一个物种正在蓬勃发展，或者如果栖息地是作为一个生态陷阱包含近交个体。因此，我们将对比各种生态特征和欧亚红松鼠（松鼠）居住在小块城市栖息地与那些生活在自然区域的种群的遗传多样性。由于高粮食供应似乎有助于增加城市密度，我们将调查丰富的自然和补充粮食资源的影响。我们预计，后者是城市野生动物的高度重要性，并通过进行公民调查，我们将能够量化这些食物来源及其空间和时间分布。我们预测，由于大量的补充食物，城市地区的松鼠全年都将有稳定的体重和状况，即使在食物短缺的季节（即春季和夏季）也是如此。这可能与更多的生殖个体相结合。然而，我们也可以检测到城市居住的负面影响，如营养不良，由不平衡的饮食引起，或高寄生虫负荷，由人工喂养场所的高个体间接触率引起。这些负面影响可能抵消上述好处，并可能说明人口生存与个人健康之间的权衡。可用的城市绿色斑块也可能作为汇生境存在;由于在高度城市化的基质中移动机会减少，可能发生不利于人口健康的近亲繁殖。最后，为了全面了解饮食和能量预算之间的相互作用，我们将进行一个食物选择实验，结合能量需求的测量。这将有助于我们量化城市化对新陈代谢的影响，并了解不同栖息地的能量和营养限制。该项目的成果不仅与城市野生动物管理和保护做法有关，而且还与自然地点野生动物种群的管理有关。由于过度扩张的城市栖息地的压力，动物被迫使用城市，但如果城市象征着下沉栖息地，物种仍然需要消失的森林才能生存。了解潜在的机制，并制定适当的行动来面对这些矛盾的条件是自然保护的主要未来挑战之一。