dc.contributor.author |
Maimela, Lerato T.
|
|
dc.contributor.author |
Chimimba, Christian Timothy
|
|
dc.contributor.author |
Zengeya, Tsungai Alfred
|
|
dc.date.accessioned |
2023-07-05T04:35:53Z |
|
dc.date.available |
2023-07-05T04:35:53Z |
|
dc.date.issued |
2022-09-27 |
|
dc.description |
SUPPLEMENTARY TABLE S1
Frequency of occurrence (%) of prey items in the diets of indigenous and
alien invasive fish species in the catchments of the Blyde and Treur rivers,
Mpumalanga Province, South Africa. |
en_US |
dc.description |
SUPPLEMENTARY TABLE S2
Trophic position (TP), corrected Carbon (Ccorr) and values of isotopic
niche (SEAc) for indigenous and alien invasive (bold) fish species sampled
in uninvaded and invaded catchments of the Blyde and Treur rivers,
Mpumalanga Province, South Africa. |
en_US |
dc.description |
SUPPLEMENTARY TABLE S3
Isotopic niche overlap among fish species in river sections invaded by
rainbow trout (Oncorhynchus mykiss) on the Blyde River, South Africa.
Extent of overlap was classified as low (< 40%), intermediate (40 to 60%)
and high (> 60%) (Langton, 1982). |
en_US |
dc.description |
SUPPLEMENTARY TABLE S4
Isotopic niche overlap among fish species in the Treur River, South Africa
that is free of rainbow trout (Oncorhynchus mykiss) invasion. Extent of
overlap was classified as low (< 40%), intermediate (40 to 60%) and high
(> 60%) (Langton, 1982). |
en_US |
dc.description |
SUPPLEMENTARY TABLE S5
Isotopic matrices of food webs of fish communities sampled in sites
invaded by rainbow trout and sites free of invasion on the Blyde and
Treur rivers, Mpumalanga Province, South Africa. |
en_US |
dc.description |
DATA AVAILABILITY STATEMENT : The original contributions presented in the study are
included in the article/Supplementary Material, further
inquiries can be directed to the corresponding author. |
en_US |
dc.description.abstract |
The introduction of alien predatory fish such as rainbow trout (Oncorhynchus
mykiss) can have a significant effect on indigenous fish communities such as
altering the structure and dynamics of food webs. Quantifying the trophic niche
utilised by the alien fish species is therefore important to aid our understanding
of how their feeding strategies might aid establishment, define their functional
role and inform on potential impacts. This study assessed food web interactions
between fish communities in river reaches that are invaded by O. mykiss and
sections that are free of invasions in the upper Blyde River catchment, South
Africa. It specifically evaluated the hypothesis that O. mykiss invasion is likely to
lead to a decrease in the trophic functional diversity through predation and that
indigenous fish will shift their trophic niche to either minimise competition with,
or avoid predation, by O. mykiss. Gut content and stable isotope analyses were
used to determine trophic interactions. Fish communities in uninvaded areas
utilised fewer and similar food sources and occupied lower trophic levels, than
fish communities in invaded areas. Oncorhynchus mykiss fed mainly on
invertebrates and at trophic levels similar to and or lower than indigenous
fishes. This suggests that their current impact on indigenous fish communities is
mainly through competition for resources. We posit that O. mykiss invasions
reduced the abundance of indigenous fishes and thereby reduced predation
pressure on aquatic invertebrates, with a knock-on effect on the trophic interrelationships among fish assemblages. Our findings are consistent with
other studies in South Africa that have shown that the impacts of O. mykiss
invasion can lead to a decline and fragmentation of indigenous species
populations and niche shifts. |
en_US |
dc.description.department |
Mammal Research Institute |
en_US |
dc.description.department |
Zoology and Entomology |
en_US |
dc.description.librarian |
am2023 |
en_US |
dc.description.sponsorship |
The DSI-NRF Centre of Excellence for Invasion Biology, the South African Department of Forestry, Fisheries, and the Environment (DFFE) and the National Research Foundation. |
en_US |
dc.description.uri |
https://www.frontiersin.org/journals/environmental-science |
en_US |
dc.identifier.citation |
Maimela, L.T., Chimimba, C.T. & Zengeya, T.A.
(2022), Niche expansion by
indigenous fish species following the
introduction of rainbow trout
(Oncorhynchus mykiss) in a subtropical
river system, upper Blyde River,
South Africa.
Frontiers in Environmental Science 10:949353.
DOI: 10.3389/fenvs.2022.949353. |
en_US |
dc.identifier.issn |
2296-665X (online) |
|
dc.identifier.other |
10.3389/fenvs.2022.949353 |
|
dc.identifier.uri |
http://hdl.handle.net/2263/91260 |
|
dc.language.iso |
en |
en_US |
dc.publisher |
Frontiers Media |
en_US |
dc.rights |
© 2022 Maimela, Chimimba and
Zengeya. This is an open-access article
distributed under the terms of the
Creative Commons Attribution License
(CC BY). |
en_US |
dc.subject |
Competition |
en_US |
dc.subject |
Predation |
en_US |
dc.subject |
Trophic dispersion |
en_US |
dc.subject |
Niche position |
en_US |
dc.subject |
Enteromius treurensis |
en_US |
dc.subject |
Treur river |
en_US |
dc.subject |
Rainbow trout (Oncorhynchus mykiss) |
en_US |
dc.subject |
Treur River barb (Enteromius treurensis) |
en_US |
dc.subject |
SDG-14: Life below water |
en_US |
dc.title |
Niche expansion by indigenous fish species following the introduction of rainbow trout (Oncorhynchus mykiss) in a subtropical river system, upper Blyde River, South Africa |
en_US |
dc.type |
Article |
en_US |