ABSTRACT

Consumption of seeds by fruit-eating animals is one of the most effective dispersal mechanisms for plants, yet little is known about dispersal by marsupial vectors. In the face of habitat fragmentation and the recent extinction or decline of many marsupial species in southern Australia, addressing knowledge gaps on vertebrate vectors is critical to determine deficiencies in seed dispersal. Here we examine one potential dispersal vector for the seeds of Cassytha pubescens, a native hemi-parasitic vine that contributes to vegetation complexity within many woodland habitats in southern Australia that are threatened by fragmentation. To determine the potential dispersal role of mammals for Cassytha pubescens within southern Australian woodlands, we collected and examined 46 scat samples from the omnivorous, nationally endangered southern brown bandicoot, Isoodon obesulus, over two fruiting (summer) seasons. Of the 46 scats, five had up to six seemingly undigested seeds of C. pubescens, indicating that I. obesulus consumes the fruits and may act as a disperser for this vine. Our findings improve understanding of the role of marsupials like bandicoots in dispersing native plant seed and may help to inform conservation management priorities to protect ecosystem function more effectively in fragmented woodlands threatened by loss of vertebrate seed vectors.

摘要

吃水果的动物食用种子是植物最有效的传播机制之一，但对有袋动物的传播知之甚少。面对栖息地破碎化和最近澳大利亚南部许多有袋动物物种的灭绝或衰退，解决脊椎动物媒介的知识空白对于确定种子传播的缺陷至关重要。在这里，我们研究了一种潜在的散布媒介Cassytha pubescens的种子，这是一种原生的半寄生藤本植物，有助于澳大利亚南部许多受到破碎化威胁的林地栖息地的植被复杂性。确定哺乳动物对长毛毛竹芋的潜在传播作用在澳大利亚南部的林地中，我们在两个结果期（夏季）期间收集并检查了来自全国濒临灭绝的杂食性南方棕袋狸Isoodon obesulus的 46 个粪便样本。在 46 个粪便中，有 5 个具有多达 6 个看似未消化的C. pubescens种子，表明I. obesulus消耗果实并可能充当这种藤蔓的分散剂。我们的研究结果加深了对袋狸等有袋动物在传播本地植物种子中的作用的理解，并可能有助于为保护管理优先事项提供信息，以便在受到脊椎动物种子载体丧失威胁的破碎林地中更有效地保护生态系统功能。