Animals that feed on fruits have the potential to play a key role in vegetation dynamics, assisting in plant succession and maintenance of floral diversity. Seeds may be ingested, passed through the gut and voided to the soil. Through this action seeds are dispersed to new sites (endozoochory). Removal of pulp from fleshy fruits during transport through the gut may also assist in the stimulation of germination. This study compared the germination response of seeds of the Australian bluebell, Billardiera fusiformis, retrieved from faecal pellets of three native mammals (quokka Setonix brachyurus, Gilbert's potoroo Potorous gilbertii and bush rat Rattus fuscipes) with that of freshly collected and aged, but non-ingested seeds, from Two Peoples Bay Nature Reserve, Western Australia. Ingestion of seeds of B. fusiformis by quokkas, Gilbert's potoroos and bush rats increased germination by 58%, 31% and 2% respectively over a control (seeds physically removed from freshly collected fleshy fruit). When placed in dry storage for over a year, however, both ingested and non-ingested seeds displayed significant increases in percent germination.
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... Seeds form an important dietary component for many Australian mammals (Quin 1985;Murray et al. 1999;Gibson 2001;Bice & Moseby 2008). Australian seed-eating mammals are recognised as potentially important seed predators (Ballardie & Whelan 1986;Auld & Denham 1999;Mills, Gordon & Letnic 2018), but the extent to which they disperse seeds via endozoochory has received little research attention (Williams et al. 2000;Cochrane, Friend & Hill 2005). Seed predation should not automatically be equated with seed removal as some seeds may be dispersed via caching or endozoochory (Hulme 2002). ...
... penicillata) and musky rat-kangaroos (Hypsiprymnodon moschatus) are known to cache seeds, leading to increased dispersal and germination potential (Dennis 2003;Chapman 2015;Murphy et al. 2015). In addition, research on endozoochory in Australian non-volant mammals also indicates that species such as Gilbert's potoroo (Potorous gilbertii) and common brushtail possums (Trichosurus vulpecula) may pass viable seeds (Cochrane, Friend & Hill 2005;Wotton & McAlpine 2015). However, the role of most non-volant seed or fruit-eating Australian mammals in seed dispersal through endozoochory is unknown. ...
... Research on endozoochory in Australian marsupials is rare, but consumption by Potorous gilbertii and Setonix brachyurus increased germination in Billardiera fusiformis (Cochrane, Friend & Hill 2005). Similarly, we found that consumption by captive quenda increased germination in G. calycinum. ...
Mammal-seed interactions are important for structuring vegetation communities across a diverse range of ecosystems worldwide. Many Australian mammals consume seeds, but their role in seed dispersal has not been well explored. The translocation of Australian mammals for the purposes of ecosystem restoration is increasing. Digging mammals,
i.e. species that dig to obtain food or create shelter, are commonly the focus of these translocations because they are ecosystem engineers but an understanding of their role in seed dispersal is lacking. We aimed to expand the understanding of endozoochory in Australian digging mammals by determining whether seeds consumed by select species remain viable and able to germinate. Firstly, we investigated the mean retention time and the postconsumption germination capacity of Australian seeds (Acacia acuminata, Dodonaea viscosa and Gastrolobium calycinum) likely to be consumed by quenda (Isoodon fusciventer) and woylies (Bettongia penicillata ogilbyi) while in captivity. Secondly, we collected scat samples from five wild digging mammal species (boodie, B. lesueur; woylie, B. penicillata; bilby, Macrotis lagotis; golden bandicoot, I. auratus and quenda, I. fusciventer) known to consume seeds across nine sites in Western and South Australia. We searched the scat samples for seeds, identified the recovered
seeds and then tested their viability and germination capacity. Mean excretion times in captive individuals were 14 hours for quenda and 24 hours for woylies, but some seeds were retained in their digestive passages for up to 39.5 and 55.5 hours, respectively. In captive settings, viable seeds of all plant species were retrieved from both quenda and woylie scats and only G. calycinum seeds ingested by quenda (62%) had a significantly higher germination percentage than control seeds (34%). In wild animals, we found that the abundance of intact seeds in scats was generally low but 70% of the retrieved seeds appeared viable. Five species of seed collected from scats of wild digging mammals germinated under laboratory conditions. Our results show that viable seeds are deposited in the scats of Australian digging mammals, indicating that these species may play a more important role in seed dispersal than previously considered. Digging mammals have the potential to contribute to ecosystem restoration efforts through the dispersal of viable seeds but there is also a risk that non-native species could be dispersed. These costs and
benefits should be considered by practitioners when planning reintroductions of digging mammals.
... The passage of the diaspore through the animal's gut can either enhance or inhibit its germination (Willson 1983;Yagihashi et al. 1998;Izhaki and Safriel 1990;Fukui 1996;Traveset et al. 2001). For example, longer retention within the digestive system can cause abrasion to the seed/fruit coat or removal of some parts of the diaspore coating (e.g., pulp), thus enhancing diaspore germination (Beveridge 1964;Barnea et al. 1990;Cochrane et al. 2005). Endozoochory also enables plants to occupy new habitats and maintain genetic diversity (Cochrane et al. 2005;Costa et al. 2014). ...
... For example, longer retention within the digestive system can cause abrasion to the seed/fruit coat or removal of some parts of the diaspore coating (e.g., pulp), thus enhancing diaspore germination (Beveridge 1964;Barnea et al. 1990;Cochrane et al. 2005). Endozoochory also enables plants to occupy new habitats and maintain genetic diversity (Cochrane et al. 2005;Costa et al. 2014). This can be understood as a process of, e.g., colonization of new habitats by annual, perennial plants and developing adaptations to a new environment. ...
Myxodiaspory (formation of mucilage envelope around seeds and fruits) is a common adaptation to dry habitats known in many families of Angiosperms. The mucilage envelope of some seeds seems to be also a unique morphological adaptation which protects myxospermatic diaspores while passing through the bird’s digestive system. To evaluate the protective potential of mucilage, we fed the diaspores of seven plant species (representing three different mucilage types and three species of non-mucilaginous plants) to pigeons, Columba livia domestica. Twenty-four hours later, we collected the droppings of pigeons and examined a total of 18,900 non-destroyed diaspores to check for mucilage presence and germination ability. Out of all the examined diaspores, 4.5% were mucilaginous seeds. Among them, the highest number (12.2–13.5%) of viable diaspores belonged to the hemicellulosic type of mucilage (from Plantago species). Only 3.7% of germinating diaspores with pectic mucilage (Linum usitatissimum) were collected, and no seeds representing cellulosic mucilage (e.g., Ocimum basilicum). For non-mucilaginous plants, we collected only a few individual seeds (0.1% out of 8100 seeds used). We noted that the mucilaginous seeds found in the droppings were able to germinate; however, the germination ability was generally smaller in comparison to the control (i.e., not digested) seeds. Our results revealed that the presence of mucilage envelope has an impact on diaspore dispersal and survivability. With our experiments, we demonstrated for the first time that the mucilage envelope, especially of the non-cellulosic type, supports endozoochory. We also showed that non-mucilaginous seeds can be occasionally dispersed via endozoochory and are able to germinate. The results of our studies can explain the ways of plants distribution at a small, local scale as well as in long-distance dispersal, e.g., between islands or even continents.
Nguyen VP, Needham AD and Friend JA, 2005. A quantitative dietary study of the 'Critically Endangered' Gilbert's potoroo Potorous gilbertii. Australian Mammalogy 27: 1-6. Faecal analysis from the only known population of Gilbert's potoroo (Potorous gilbertii) near Albany, Western Australia revealed that it, like other rat-kangaroo species is primarily mycophagous. Diet was determined by faecal collections from live-captured animals within Two Peoples Bay Nature Reserve. Microscopic examination of samples collected from June - September 2000 and additional samples from storage, found fungi to comprise over 90% of faecal matter. A total of 44 fungal spore types were identified with many believed to be of hypogeous origin. Fungal spores belonging to the genera Mesophellia, Elaphomyces, Hysterangium and an unknown spore type (Unknown 1) were frequently recorded in samples. Non-fungal material including plants (stems, roots and seeds) and invertebrates represented the remainder. This investigation found that P. gilbertii fed almost exclusively on fungi and could be considered a specialised mycophagist.
The ripening fruit of nitre bush (Nitraria billardieri) is eaten in great quantities by emus. The seed is highly resistant to digestion. Germination increases considerably following ingestion; 67% of emu-ingested seed germinated after twenty-four days but only 17% of hand-collected seed. Germination of emu-ingested seed was also much quicker (50% vs. 3% in four days). Emus apparently facilitate germination by removal of the salt-rich pericarp; mammals are much less effective. Emus may play an integral role in the successful establishment of nitre bush where heavy clay soils are dominant and seed is rarely buried. Where nitre bush occurs on light textured soils, seed germinates readily without prior avian ingestion, provided it has first been covered by wind-blown sand.
The structure and function of the gastrointestinal tracts of 2 potoroine marsupials, Aepyprymnus rufescens, the rufous rat-kangaroo, and Potorous tridactylus, the long-nosed potoroo, were examined by the use of radiographic and fluoroscopic techniques. In both species barium sulphate given by mouth entered the sacciform forestomach within 20 min of dosing, but in the same time the hindstomach and duodenum were clearly outlined. Contrast medium reached the hindgut within 1 to 2 h, but was retained there for at least 24 h. A proportion of radio-opaque particles given by mouth also bypassed the sacciform forestomach, but those that entered the gastric region were retained there for up to 93 h. The stomach constituted 50% of total gut capacity, and the hindgut (caecum and colon) 35%. The sacciform forestomach was the largest gastric region. It is concluded that, on the basis of anatomy and digesta movements, the forestomach may be less important, and the hindgut more important, in fermentative digestion in the Potoroinae than in the Macropodidae.
Dromaius novaehollandiae is no longer common in the
north-east coastal region of New South Wales and its habitat is increasingly
being fragmented by development. From a pilot study using Emu faecal droppings
collected at Main Camp it is established that viable seeds are dispersed by
Emus in the region. It is suggested that this viable seed dispersal, combined
with the possible extensive range of plant species dispersed indicates Emus
may play an important, yet overlooked role in the maintenance of the recorded
high regional biodiversity. The Emu’s ability to transport many large
seeds over long distances could prove an important link between fragments of
remnant vegetation by helping to maintain the genetic mix in plant
The diet of the long-nosed potoroo, Potorous tridactylus, in south-western Victoria, was investigated
by the microscopical identification of faecal remains. P. tridactylus is omnivorous: the main component
of the diet was fungi, and other important items included hard-bodied arthropods, vascular plant tissues,
seeds and fleshy fruits. There was a seasonal switch in the relative proportions of the main dietary
components between the autumn-winter and spring-summer periods of the year. During autumn and
winter, the main components were fungi and seeds. In spring and summer, fewer fungi were eaten and
the proportions of arthropods, plant tissues, fleshy fruit and flowers in the diet increased. Identification
of fungal spores revealed the presence of at least 50 species in the diet, most of which have a hypogeal
fruiting habit. Hypogeal fungi form ectotrophic mycorrhizal associations with forest trees and are
important in the health and productivity of forests. They lack active mechanisms for spore dispersal
and are dependent upon mycophagous animals. The role of mycophagous small mammals, such as
P. tridactylus, in the health of forest ecosystems may be more important than previously recognised.
Carpobrotus modestusis an inland succulent perennial with fleshy fruits. In a semi-arid area carrying tall mallee shrublands with a range of different fire histories, it was shown thatC. modestuspopulations appear in the immediate post-fire period, then mature and die within 7 years as the regenerating mallee shrubland becomes taller and denser. This post-fire pioneer behaviour is also common in the related southern AfricanErepsia. In a germination trial of freshC. modestusseed, all seeds remained dormant. However, seeds found in rabbit and grey kangaroo faeces germinated readily. Fire ecology and frugivory in subfamily Mesembryanthemoideae are briefly reviewed.