Symbiotic Relationships for Rhinos | Sciencing
Although widely accepted in the literature, this theory has never been tested in the field. These results suggest that the oxpecker-mammal relationship is more .. and Laurie, ), commensal on impala, and mutualistic on rhinoceroses. Taking part in mutual relationships is beneficial for both individuals. exists between the sanguinivorous oxpecker and the herbivorous rhino. These ants exhibit a close relationship with the swollen thorn Acadia plant. and experimental oxen for each replicated experiment (Mann-Whitney test throughout ). amount of time oxpeckers spent on their hosts, removal attempts by rhino.
They eat tough plant matter but are not able to digest the cellulose their food contains.
Feeding preferences of Oxpeckers in Kruger National Park, South Africa
They rely on microflora that are able to digest this material, releasing nutrients like fatty acids that the host animal can absorb and use for energy — an example of mutualism. The hosts don't ruminate like cattle; the microflora work in the host's hindgut. Studies of white rhino dung show bacteria of the phyla Firmicutes and Bacteroidetes dominating the microflora living in the rhino gut, along with many other unclassified bacteria. A Symbiotic, but Parasitic, Relationship in a Rhino's Gut The rhinoceros bot fly Gyrostigma rhinocerontis lives exclusively in the digestive tracts of both white and black rhinoceroses.
The adults, which are the largest flies in Africa, lay their eggs on the skin of rhinos, and the larvae burrow into the rhino's stomach, where they attach and live through larval stages called "instars.
Then they have only a few days to find another rhinoceros host. This symbiotic relationship has no benefit to the rhino hosts, while the flies are "obligate parasites," which means they're dependent on the rhinos — they can't complete their life cycle without them.
A Highly Visible Example of Symbiosis Oxpecker birds Buphagus erythrorhynchusalso called tickbirds, specialize in riding on large African animals, including rhinos and zebras, feeding on external parasites like the bot-fly larvae and ticks. The International Rhino Foundation describes how mynah birds serve the same role on rhinos in India.
This preference could be a result of larger ungulates providing a greater surface area for ectoparasites, which are therefore able to carry larger tick loads Horak et al.
Additionally, the three most preferred host species are often gregarious, travelling and feeding in large numbers, and therefore potentially increasing tick abundance, transmission and prevalence Koenig Differences in host preferences were observed between populations of Red-billed Oxpecker in the Shingwedzi and Skukuza regions, with the Shingwedzi population selecting for smaller ungulates see Figure 2. Red-billed Oxpeckers appear to be limited to medium and small-sized ungulates, such as Kudu and Impala, in the northern parts of KNP.
This is most likely because of a home range overlap with Yellow-billed Oxpeckers, resulting in interspecific competition Koenig The larger in terms of body size Yellow-billed Oxpecker is territorial and capable of outcompeting the smaller Red-billed Oxpecker Hall-Martinpermitting the former a preferential choice of ungulates.
The study also shows that Red-billed Oxpeckers in the southern regions of KNP utilised the preferred large ungulates in the absence of Yellow-billed Oxpeckers, whereas their preference shifted to smaller ungulates in the presence of Yellow-billed Oxpeckers. This further supports the notion of interspecific competition between Red-billed and Yellow-billed Oxpeckers for access to larger ungulate hosts. Contrary to the results from the present study, Hustler and Koenig in Zimbabwe and Kenya respectively did not find any differences in host ungulate preferences when both species occurred within the same geographic region.
Furthermore, Koenig did not find any marked differences in the host species preferences of Red-billed Oxpeckers when comparing between areas of sympatry and areas of allopatry. Perhaps these differences between the Kenya study and the KNP findings could be attributed to differences in ungulate densities between the two sites. One would assume that the Kenya sites Masai Mara Reserve and Lake Nakuru National Park had a high abundance of large ungulates compared to KNP, hence a marked host preference would only be apparent in lower ungulate densities where interspecific competition is unavoidable.
However, that hypothesis cannot be tested without a measure of ungulate densities from all sites. Surprisingly, the PI results in the present study differed from Grobler and Stutterheim and Stutterheim Optimal foraging strategy Pyke will predict that animals will concentrate on the most abundant and profitable food source.
For example, there were fewer White Rhinoceros and Hippopotamus in KNP in the s compared to the present-day population It is therefore reasonable to conclude that as White Rhinoceros and Hippopotamus numbers increased, Red-billed Oxpeckers responded by selecting for these new abundant host species with potentially higher tick loads and less hair to hide the ticks. Giraffe remained the most preferred host species in both the northern and southern regions of the park.
This could also be a detection bias, given that it is possibly easier for flying birds to detect Giraffe compared to other shorter species. This is further supported by Oxpeckers' preference for White Rhinoceros and Hippopotamus both large ungulatesrecorded as host species in Skukuza. Interestingly, Impala, an abundant, small-sized ungulate, was less preferred as a host species across studies. This surprising contradicts what has been reported by GroblerStutterheim and Stutterheim and Hart et al.
Both Red-billed and Yellow-billed Oxpeckers displayed a preference for the back and head regions of their respective host species. Red-billed Oxpeckers also preferred the necks of Giraffe. Additionally, Oxpeckers prefer feeding on the back regions of a host species since this is easily accessible and provides a stable perch WeeksThe Oxpeckers role in the Animal Kingdom