Godínez-Alvarez Héctor, Ríos-Casanova Leticia, Peco Begoña
Unidad de Biología Tecnología y Prototipos Facultad de Estudios Superiores Iztacala Universidad Nacional Autónoma de México Tlalnepantla México.
Centro de Investigación en Biodiversidad y Cambio Global Departamento de Ecología Universidad Autónoma de Madrid Madrid España.
Ecol Evol. 2020 Apr 27;10(12):6136-6143. doi: 10.1002/ece3.6285. eCollection 2020 Jun.
Frugivorous birds vary in seed dispersal effectiveness (SDE) depending on their body mass. It has been suggested that large birds are more effective dispersers than small ones because they consume a large number of fruits, disperse seeds of distinct sizes, and transport seeds over long distances. Yet, few studies have evaluated the impact of body mass on SDE of birds. In this study, we compiled one database for the quantity (i.e., frequency of visits to plants and number of seeds removed per visit) and quality (i.e., germination of seeds after gut passage and gut retention time of seeds) of seed dispersal by frugivorous birds to evaluate the impact of body mass on SDE. In addition, we compiled data on plant characteristics such as life-form, fruit type, number of seeds per fruit, and size of seed to evaluate their influence on the quantity and quality of seed dispersal. Data were analyzed with linear mixed effects models and quantile regressions to evaluate the relationship between body mass of birds and quantity, quality, and SDE, in addition to the influence of plant characteristics on SDE. The body mass of birds was negatively related to the frequency of visits to plants. Furthermore, it was positively related to the number of seeds removed per visit, although negatively related to seed size. The life-form of plants was the only factor explaining the germination of seeds after gut passage. Yet, the body mass of birds was positively related to the gut retention time of seeds. Small and medium birds have a relatively higher SDE than large birds. These results differ from the assertion that large birds are more effective dispersers of plants. Small and medium birds are also effective dispersers of plants that should be preserved and protected from the impact of human activities.
食果鸟类的种子传播效率（SDE）因其体重而异。有人认为，大型鸟类比小型鸟类更有效地传播种子，因为它们消耗大量果实，传播不同大小的种子，并将种子远距离运输。然而，很少有研究评估体重对鸟类种子传播效率的影响。在本研究中，我们汇编了一个数据库，用于评估食果鸟类种子传播的数量（即对植物的访问频率和每次访问移除的种子数量）和质量（即种子经肠道后发芽情况和种子在肠道内的保留时间），以评估体重对种子传播效率的影响。此外，我们汇编了有关植物特征的数据，如生活型、果实类型、每个果实的种子数量和种子大小，以评估它们对种子传播数量和质量的影响。使用线性混合效应模型和分位数回归分析数据，以评估鸟类体重与数量、质量和种子传播效率之间的关系，以及植物特征对种子传播效率的影响。鸟类体重与对植物的访问频率呈负相关。此外，它与每次访问移除的种子数量呈正相关，尽管与种子大小呈负相关。植物的生活型是解释种子经肠道后发芽情况的唯一因素。然而，鸟类体重与种子在肠道内的保留时间呈正相关。中小型鸟类的种子传播效率相对高于大型鸟类。这些结果与大型鸟类是更有效的植物传播者这一观点不同。中小型鸟类也是植物的有效传播者，应该受到保护，免受人类活动的影响。
