鸟类取食中国沙棘果实的方式及其对种子的传播作用

2003年9月～2004年3月，定期观察取食中国沙棘果实的鸟类及其取食方式。共记录取食中国沙棘果实的鸟类18种，其取食果实的方式主要有：1)直接在树冠上吞食果实，有时候在吞食后将种子呕出；2)将果实从树上衔走后，在栖息处吞食或啄食；3)将果实啄落至地面，然后取食果肉和种子，留下果皮；4)啄破果皮，吸食果肉，留下果皮及种子；5)从顶端将果皮啄破后，仅取食里面的种子。不同的取食方式决定了它们对沙棘种子的传播作用不同。收集鸟粪便中的种子与完整的干果实及人工剥离果肉和内果皮的种子做萌发对比实验，结果表明，鸟类消化道过程对种子的萌发有一定影响，但萌发率仍较高。沙棘为多种鸟类提供食物，而鸟类则为沙棘传播种子，它们之间形成一种互利关系。

Fruits foraging patterns and seed dispersal effect of frugivorous birds on Hippophae rhamnoides sinensis

Behaviors of 18 species of birds eating fruits of Hippophae rhamnoides sinensis were observed from September 2003 to March 2004.Their frugivorous ways were found to be various: 1)directly swallowing the fruits on the crown of the shrubs and sometimes regurgitating seeds soon after;2)carrying the fruits to their perching sites and swallowing;3)pecking the fruits from the shrubs to the ground,eating pulp and seeds but leaving pericarp;4)pecking through the pericarp,eating pulp and leaving pericarp and seeds;5)pecking through the pericarp on the top of fruits,and only eating seeds.These ways have different effects on seed dispersing of H.rhamnoides sinensis.The germination experiment of three groups of seeds (seeds from feces,dry fruits and extracted seeds from dry fruits) was compared.Although ingestion process of birds had some effects on seed germination of H.rhamnoides sinensis,the seeds from feces still had a relative higher germination ratio.H.rhamnoides sinensis provides food to a variety of frugivorous birds,and the birds disperse its seeds.Thus,mutually beneficial relationship between them was formed.