Integrating Ecosystem Services and Disservices in Valuing Smallholder Livestock and Poultry Production in Three Villages in South Africa
- Authors: Herd-Hoare, Shannon C , Shackleton, Charlie M
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/176089 , vital:42659 , https://doi.org/10.1016/j.ufug.2020.126740 , https://doi.org/10.21504/RUR.c.5388515.v1
- Description: This study presents an integrated examination of both the ecosystem services (ES) and ecosystem disservices (EDS) associated with smallholder animal husbandry in rural livelihoods in three villages in southeast South Africa. It recognises the contribution of ES supporting and resulting from smallholder livestock and poultry production, but also details the limiting factors or EDS, such as tick-borne disease, birds of prey or unpalatable rangeland, produced by the same system. Using a mixed-methods approach, including focus group discussions with various Participatory Learning and Action (PLA) activities, key informant interviews, household surveys and land-use change mapping on GIS, we consider the relative value and benefits from ES after the effects of EDS, as well as the management and strategies that households adopt to minimise EDS.
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- Date Issued: 2020
Maintenance of public and private urban green infrastructure provides significant employment in Eastern Cape towns, South Africa:
- Authors: King, Andrew , Shackleton, Charlie M
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/176074 , vital:42657 , https://doi.org/10.1016/j.ufug.2020.126740
- Description: Urban green infrastructure (UGI) provides numerous environmental, social and economic benefits through direct and indirect use of ecosystem services. The maintenance of UGI also provides work opportunities for skilled and unskilled workers in the public and private sectors, so-called green collar jobs. However, the extent and benefit of such employment has rarely been examined, especially in a developing country context where unemployment is often high. We quantified the number of green collar jobs and wage levels across all green collar categories in 12 towns of the Eastern Cape via means of questionnaires and interviews. Overall, we enumerated 17 429 jobs, receiving approximately ZAR503 million (US$37 million) per year. The number of jobs was strongly linked to town size, but the number of jobs per unit area was inversely related to the level of underdevelopment or deprivation per town.
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- Date Issued: 2020
Rhodes University Library Library and Information Services (LIS) Strategic Plan (2020 -2022)
- Authors: Danster, Nomawethu
- Date: 2020
- Language: English
- Type: Text
- Identifier: http://hdl.handle.net/10962/155082 , vital:39852
- Description: The Rhodes University Library strategic plan 2020 - 2022 is informed by the 2020 Academic Library standards developed by the Committee of Higher Education Libraries in South Africa (CHELSA), a coalition of all 26 Higher Education Libraries in South Africa. The standards seek to advance the role of academic libraries as partners to the teaching, learning and research endeavors of South African higher education institutions. The framework is further influenced by the principles as laid down by the 2018 National Policy for Library and Information Services (LIS) in South Africa which seeks to promote and develop the LIS Sector to contribute to the development of a responsive, responsible, and deliberative informed and reading nation. The Strategy is aligned to the Rhodes University (RU) Institutional Development Plan (2018 -2022) and the seven (7) RU goals outlined in the 2020 RU Annual Performance Plan. The seven RU goals are premised from the two most important documents that define the academic project; the RU Institutional Development Plan (IDP) and transformation imperatives document, the RU Institutional Transformation Plan (ITP). The Strategy is made up of the four strategic elements; the overall RU Vision and Mission, the LIS Purpose Statement, Values, Broad Focus Areas (BFAs)and Key Performance Areas (KPAs) that are all aligned to the seven (7) RU goals. Both the vision and mission are derived from the institutional IDP. The LIS further developed purpose statement, values, developed the BFAs and KPAs that translated to action plans and activities that form the Annual Operating Plan for the LIS.
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- Date Issued: 2020
Synthetic, characterization and cytotoxic studies of ruthenium complexes with Schiff bases encompassing biologically relevant moieties:
- Authors: Maikoo, Sanam , Dingle, Laura M K , Chakraborty, Abir , Xulu, Bheki , Edkins, Adrienne L , Booysen, Irvin N
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/165429 , vital:41243 , https://doi.org/10.1016/j.poly.2020.114569
- Description: This research study describes the formation and characterization of novel paramagnetic ruthenium complexes, cis-Cl, trans-P-[RuIIICl2(carboim)(PPh3)2] with bidentate chelating carbohydrazide Schiff bases (carboim = bpc for 1, ttc for 2 and tpc for 3). These metal complexes were synthesized by the equimolar coordination reactions of trans-[RuCl2(PPh3)2] with N-[1,3-benzothiazole-2-ylmethylidene]pyridine-2-carbohydrazide (Hbpc), N-((uracil-5-yl)methylene)thiophene-2-carbohydrazide (Httc) and N-[(uracil-5-yl)methylidene]pyridine-2-carbohydrazide (Htpc), respectively. Physicochemical techniques including nuclear magnetic resonance-, electron-spin resonance- and infrared spectroscopy, UV–Vis spectrophotometry, voltammetry as well as molar conductivity measurements provided definitive determinations of the respective ruthenium compounds’ structures.
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- Date Issued: 2020
The degree, extent and value of air temperature amelioration by urban green spaces in Bulawayo, Zimbabwe:
- Authors: Ngulani, T , Shackleton, Charlie M
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/176061 , vital:42656 , https://doi.org/10.1080/03736245.2019.1685405
- Description: Urban greenery provide a variety of goods and services to city dwellers. A core one is amelioration of the urban heat island effect. However, the many estimates from temperate regions cannot be extrapolated to the tropics, where more empirical studies are required to guide urban planning and optimization of green infrastructure design and distribution. This study reports on the temperature differentials in fortnightly readings, in winter and summer, between 12 urban green spaces and the surrounding built-up urban matrix at increasing distances from each green space. Additionally, the value of energy costs saved for air conditioning by urban greenery was calculated.
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- Date Issued: 2020
The genetic legacy of fragmentation and overexploitation in the threatened medicinal African pepper-bark tree, Warburgia salutaris:
- Authors: Senkoro, Annae M , Talhinhas, Pedro , Simões, Fernanda , Batista-Santos, Paula , Shackleton, Charlie M , Voeks, Robert A , Marques, Isabel , Ribeiro-Barros, Ana I
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/176395 , vital:42690 , https://doi.org/10.1016/j.ecoser.2020.101201
- Description: The pepper-bark tree (Warburgia salutaris) is one of the most highly valued medicinal plant species worldwide. Native to southern Africa, this species has been extensively harvested for the bark, which is widely used in traditional health practices. Illegal harvesting coupled with habitat degradation has contributed to fragmentation of populations and a severe decline in its distribution. Even though the species is included in the IUCN Red List as Endangered, genetic data that would help conservation efforts and future re-introductions are absent. We therefore developed new molecular markers to understand patterns of genetic diversity, structure, and gene flow of W. salutaris in one of its most important areas of occurrence (Mozambique).
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- Date Issued: 2020
Factors associated with consistent condom use: a cross-sectional survey of two Nigerian universities
- Authors: Ajayi, Anthony Idowu , Ismail , Kafayat Olanike , Akpan, Wilson
- Date: 2019
- Subjects: Nigeria Condom Use Computer File
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/5834 , vital:44650 , https://DOI:10.1186/s12889-019-7543-1
- Description: Background: Consistent condom use is central to the prevention of transmission of human immunodeficiency virus (HIV) and other sexually transmitted diseases (STDs), especially among young adults. This study drew from a cross-sectional survey of two Nigerian universities to determine the level of consistent condom use, explored the determinants of condom use consistency and reasons for inconsistent condom use. Methods: We adopted a descriptive cross-sectional design, which involves the recruitment of 800 male and female students using stratified random sampling. Adjusted and unadjusted logistic regression models were used to examine the factors associated with consistent condom use among a final sample of 498 students who engaged in sex in the last year preceding the study. Results: Only 38.6% of sexually active participants (n = 498) used condoms consistently in the previous year. High condom self-efficacy score (AOR: 2.40; 95% CI: 1.58–3.64), discussion of HIV/STIs with sexual partner (AOR: 1.91; 95%CI: 1.29–2.83), knowing partner’s HIV status (AOR: 1.48; 95% CI: 1.02–2.16), being students of university located in a high HIV prevalence area (AOR: 2.86; 95% CI: 1.92–4.28) and engaging in sex with only steady partner (AOR: 1.74; 95% CI: 1.17–2.60) were associated with a higher odds of consistent condom use. Trust, unavailability of condoms, dislike of condoms and a perception that condoms reduced sexual pleasure were the main reasons for inconsistent use of condoms. Conclusion: The study found a low level of consistent condom use among study participants. Counselling young adults in Nigeria on condom self-efficacy, providing condoms on campuses and encouraging the discussion of sexually transmitted infections with sexual partners are central to improving the level of consistent condom use among Nigerian university students. Keywords: Condoms, Self-efficacy, Consistent condom use, HIV, Drug use, Alcohol use, Nigeria, University students
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- Date Issued: 2019
Gendered inequalities in the South African informal economy
- Authors: Rogan, Michael , Alfers, Laura C
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/474167 , vital:77697 , https://doi.org/10.1080/10130950.2019.1676163
- Description: In the early part of the post-apartheid period in South Africa, a ‘feminisation of the labour force’ coincided with an increasing concentration of women in unemployment as well as in informal and low-paid work. In other words, and as observed at the time, an improvement in female labour participation did not seem to ‘buy’ much for South African women. Accordingly, the overrepresentation of women in informal employment has been identified as a key source of gender inequality in the labour market. However, a source of gender disadvantage that has received considerably less attention is the gendered structure of earnings and occupations within the informal economy. In this paper, we examine sources of gender inequality within the South African informal economy through an analysis of a recent labour force survey and by drawing on a multi-dimensional approach to understanding risks to income security.
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- Date Issued: 2019
Perceptions and preferences for urban trees across multiple socio-economic contexts in the Eastern Cape, South Africa
- Authors: Gwedla, Nanamhla , Shackleton, Charlie M
- Date: 2019
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/177419 , vital:42820 , https://doi.org/10.1016/j.landurbplan.2019.05.001
- Description: Urban trees are vital components of urban ecosystems, and thus important for environmental quality, urban sustainability, and quality of life in cities. Regrettably, urban trees are sometimes unequally distributed both between and within towns, a pattern largely associated with differences in the social environment of cities and historical patterns of development, and the dearth in strategic management plans and systematic monitoring of the existing urban forest. Most management plans focus on ecological and arboricultural aspects at the expense of the social, and studies examining perceptions in relation urban forests are largely from developed countries. Accordingly, we conducted a study to examine the perceptions and preferences regarding urban trees of 1200 residents from 10 urban areas across multiple socio-economic contexts in South Africa.
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- Date Issued: 2019
Rapid recovery of macroinvertebrates in a South African stream treated with rotenone:
- Authors: Bellingan, Terence A , Hugo, Sanet , Woodford, Darragh J , Gouws, Jeanne , Villet, Martin H , Weyl, Olaf L F
- Date: 2019
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/140751 , vital:37915 , DOI: 10.1007/s10750-019-3885-z
- Description: South Africa’s Cape Fold Ecoregion supports a unique freshwater fish assemblage with many endemics. To mitigate impacts of alien invasive fishes on this unique assemblage, nature conservation authority CapeNature used rotenone to remove smallmouth bass (Micropterus dolomieu) from the Rondegat River. We investigated whether the rotenone treatments had an adverse impact on the aquatic macroinvertebrate community over the long-term, the first study of its kind in Africa. We monitored macroinvertebrates within treated and untreated (control) sites on multiple sampling events for 2 years before and 2 years after two rotenone treatments. We analysed the difference in invertebrate abundance between treatment and control sites before and after treatment, using generalised linear mixed models with sampling event as a random factor to partition out natural fluctuations in abundances over time.
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- Date Issued: 2019
Reflecting on feedback processes for new ways of knowing, being and acting
- Authors: Quinn, Lynn , Behari-Leak, Basturi , Ganas, Rieta , Olsen, Anne-Mart , Vorster, Jo-Anne E
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/484187 , vital:78878 , https://doi.org/10.1080/1360144X.2019.1593174
- Description: Using participatory research strategies we critically reflect on how, in a formal course for academic developers, feedback supports the induction of participants into the field. We investigated how feedback processes contribute to participants’ explorations of new ways of knowing, being, and acting as academic developers in their contexts. The process of reflecting on contested and diverse approaches to feedback has contributed significantly to theorising our practices as facilitators on the course. We argue that the kind of feedback provided by the tutors has the potential to contribute to strengthening emerging voices and practices of academic developers in the global South.
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- Date Issued: 2019
Strength and Sprint Time Changes in Response to Repeated Shuttles Between the Wickets During Batting in Cricket
- Authors: Christie, Candice J , Sheppard, Bronwyn J , Goble, David , Pote, Lee , Noakes, Timothy
- Date: 2019
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/127133 , vital:35959 , https://doi.org/10.1519/jsc.0000000000002585
- Description: Christie CJ, Sheppard B, Goble D, Pote L, and Noakes TD. Strength and sprint time changes in response to repeated shuttles between the wickets during batting in cricket. J Strength Cond Res XX(X): 000–000, 2018—No studies have investigated the impact of repeated sprints between the wickets on lower-limb strength and sprint performance. Therefore, the purpose of this study was to assess changes in knee extensor (EXT) and flexor (FLEX) strength after repeated sprints between the wickets and to relate these to changes in sprint times. Twenty batters completed 2 conditions: onewas high-volume running (HVR-twelve sprints per over) and the other, moderate-volume running (MVR-6 sprints per over) between the wickets (42 deliveries in both). Peak isokinetic torque was measured before and after each condition and sprint times were recorded. Eccentric and concentric peak torque decreased significantly (p , 0.05) at 1.05 rad˙s ̄1 for knee EXT in both conditions. There was an 18% (HVR) and 10% (MVR) decline in concentric and eccentric knee EXT peak torque. Peak FLEX torques were significantly (p , 0.05) reduced after HVR (16.7%) but not after the MVR condition (8%). There were similar declines in eccentric FLEX peak torque. Sprint times increased significantly (p , 0.05) during the HVR condition but not in the MVR condition; sprint times in the HVR condition were compromised as early as the third over. We conclude that a high volume of runs significantly reduces muscle function in the lower limbs, partly explaining the impairment in sprint performance. However, because batters slowed as early as the third over in the HVR condition, there may be some form of strategy used in anticipation of a higher overall workload. More middle wicket practices, focusing on repeat shuttle sprints while batting, should be included in the coaching program.
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- Date Issued: 2019
The diet and trophic ecology of non-native Micropterus salmoides in two South African impoundments
- Authors: Taylor, Geraldine C , Hill, Jaclyn M , Weyl, Olaf L F
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/444718 , vital:74262 , https://doi.org/10.2989/16085914.2019.1612318
- Description: Largemouth bass Micropterus salmoides is a highly successful predator that preys on fish and invertebrates. Highly popular with anglers, it is one of the most introduced and invasive fish globally, with strong potential to alter ecosystem structure and functioning. A better understanding of the trophic dynamics of M. salmoides populations is critical for effective management of its ecological impacts in their invasive range. This study investigated the diets and dietary ontogenetic shifts of M. salmoides in two South African dams along with its trophic positioning relative to other fish community members, through stomach content and stable isotope analyses. Micropterus salmoides was a top predator in both dams. In the Mankazana Dam, it depended predominately on insect prey, demonstrating a generalised feeding strategy, with shifts to include increasing proportions of fish prey with increasing size. Contrastingly, in the Wriggleswade Dam, M. salmoides displayed no ontogenetic shifts and preferred Gilchristella aestuaria, likely indicating a shift to a predominantly fish-based diet at smaller sizes, in the presence of small pelagic fish prey. Overall, M. salmoides diet was opportunistic, likely associated with prey morphology and behaviour (associated with refuge availability) and therefore directly linked to prey abundance and availability, which consequently dictated feeding strategy.
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- Date Issued: 2019
The functional significance of facultative hyperthermia varies with body size and phylogeny in birds
- Authors: Gerson, Alexander R , McKechnie, Andrew E , Smit, Ben , Whitfield, Maxine C , Smith, Eric K , Talbot, William A , McWhorter, Todd J , Wolf, Blair O
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/441609 , vital:73901 , https://doi.org/10.1111/1365-2435.13274
- Description: Facultative hyperthermia, the elevation of body temperature above normothermic levels, during heat exposure, importantly affects the wa-ter economy and heat balance of terrestrial endotherms. We currently lack a mechanistic understanding of the benefits hyperthermia provides for avian taxa. Facultative hyperthermia has been proposed to minimize rates of water loss via three distinct mechanisms: M1) by maintaining body temperature (Tb) above environmental temperatures (Te), heat can be lost non‐evaporatively, saving water; M2) by minimizing the thermal gradient when Te > Tb, environmental heat gain and evaporative water loss rates are reduced; and M3) by storing heat via increases in Tb which reduces evaporative heat loss demands and conserves wa-ter. Although individuals may benefit from all three mechanisms during heat exposure, the relative importance of each mechanism has not been quantified among species that differ in their body size, heat toler-ance and mechanisms of evaporative heat dissipation. We measured resting metabolism, evaporative water loss and real‐time Tb from 33 species of birds representing nine orders ranging in mass from 8 to 300 g and estimated the water savings associated with each proposed mechanism. We show that facultative hyperthermia varies in its benefits among species.
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- Date Issued: 2019
Tracking the decline of the world’s largest seabream against policy adjustments
- Authors: Kerwath, Sven E , Parker, Denham , Winker, A Henning , Potts, Warren M , Mann, Bruce Q , Wilke, Christopher , Attwood, Colin G
- Date: 2019
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/131433 , vital:36571 , https://doi.org/10.3354/meps12853
- Description: For most rare marine species, abundance trends are poorly estimated. This uncertainty often translates into disagreement on management regulations, impeding conservation efforts when they are most urgently required. The world’s largest sea bream, the red steenbras Petrus rupestris, has undergone a substantial and widely acknowledged decline during the 20th century. Standardised probability of encounter over the last 3 decades was used to track red steenbras abundance trajectories in 2 regions, which together represent the species’ distribution. The results predicted a reduction in abundance of 44% in the East region and 96% in the South-West region, from what was already considered to be a collapsed population at the start of the time series. The species is now largely confined to areas in the centre of its historical abundance. Content analysis of a recreational angling magazine revealed a concurrent 50% decrease in reported size between 1984 and 2012. Shore-based observer data (2009-2010) indicate that the impact of recreational fishers on this species far exceeded that of commercial fishers at the time. Regulations in the form of progressively more stringent catch and effort restrictions appear to have been largely ineffective, too lenient, implemented too late or were unsuitable to control fishing mortality for this species. This study highlights 2 fundamental challenges in management of rare marine fish species: (1) providing decision makers with a credible measure of abundance for species whose rarity limits data availability and (2) implementing effective policy changes before the specific measures become ineffective and obsolete.
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- Date Issued: 2019
Using camera traps to generate a species inventory for medium-sized and large mammals in South West Zimbabwe:
- Authors: Welch, Rebecca J , Grant, Tanith , Parker, Daniel M
- Date: 2019
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/150267 , vital:38955 , https://0-doi.org.wam.seals.ac.za/10.3957/056.049.0089
- Description: We investigated the presence of medium-sized and large mammals utilizing by-catch data from a camera trapping survey in the Mangwe District in South West Zimbabwe, an unprotected commercial livestock farming area which is impacted by human encroachment, poaching and trophy hunting. The camera trapping survey was carried out from 23 October to 5 December 2009, covered an area of 200 km2 and was initially intended to estimate the population density of leopards (Panthera pardus). The study area was split into two contiguous subsections, with each section sampled for a total of 20 days using 20 cameras. Camera trap photographs were identified to species level, then compared to a list of species thought to occur in the area according to available literature, as well as sightings from professional hunters and local landowners.
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- Date Issued: 2019
Virtual Activism: internet memes and political discourse in Nigeria
- Authors: Jimoh, Ganiyu A
- Date: 2019
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/146767 , vital:38555 , http://www.tajuniuyo.ng/Virtual Activism Internet Memes and Political Discourse in Nigeria.html
- Description: This paper examines internet memes as a unique form of narratives about political discourse in Nigeria. Through the use of social media platforms as a vehicle of political communication, internet memes about politics explore issues that contain visual metaphors aimed at provoking discourse and stimulate political participation. By employing semiotic theory, this paper examines 200 pictorial internet memes on Nigerian politics between 2015 and 2018. I argue that internet memes about politics are related to political cartoons in form and context. But unlike cartoons, memes require less artistic prowess and figurative expression in rendition but could achieve the same desire in viewers. Owing to their composition of easily digestible visual elements, they appeal to more audience who in turn could easily lend their voices to a popular meme by adding more textual or visual enhancement to create more layers of meaning.
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- Date Issued: 2019
A Case Study of Two Selected Teachers as they Integrated Dynamic Geometry Software as a Visualisation Tool in Teaching Geometry:
- Authors: Mavani, Deepak , Mavani, Beena , Schäfer, Marc
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141076 , vital:37942 , https://doi.org/10.1080/18117295.2018.1522716
- Description: This paper reports on an aspect of a larger research study conceptualised within a teacher development project in Mthatha, Eastern Cape Province. The project was initiated with the objective to develop appropriate skills to use dynamic geometry software (DGS) effectively and strategically as a teaching and learning tool for mathematics. The study reported in this paper aims specifically to ascertain how selected mathematics teachers integrated co-developed technologically aided visualisation tools in the observed lessons. The case study involved two teachers from different schools. The data sources were the classroom observations followed by stimulated reflective interviews with the teachers. The data were analysed to study the use of DGS visualisation tools in relation to Kilpatrick’s framework of teaching proficiency.
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- Date Issued: 2018
An endangered seahorse selectively chooses an artificial structure
- Authors: Claassens, Louw , Booth, Anthony J , Hodgson, Alan N
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/123718 , vital:35486 , https://doi.10.1007/s10641-018-0732-4
- Description: The development of a residential marina estate within the Knysna estuary, South Africa, introduced Reno mattresses (horizontal wire cages filled with rocks) as a novel habitat for the endangered Knysna seahorse Hippocampus capensis. Consistently high seahorse densities on these artificial structures, despite the availability of seagrass habitat, begged the question of whether this habitat was chosen by the seahorse in preference to natural vegetation. An in situ habitat choice experiment was conducted which focused on the choice made by adult H. capensis between natural vegetation (Zostera capensis) and artificial (Reno mattress) habitat within a choice chamber. Seahorses were significantly more likely to move away from Z. capensis onto a Reno mattress structure or remain on this structure. This study concludes that higher H. capensis densities on Reno mattresses within Thesen Islands Marina are owing to some positive feature of this habitat and the underlying processes responsible for the choice made by this species (additional food, holdfasts, protection) can now be investigated.
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- Date Issued: 2018
Contrasting responses in the niches of two coral reef herbivores along a gradient of habitat disturbance in the Spermonde Archipelago, Indonesia
- Authors: Plass-Johnson, Jeremiah G , Bednarz, Vanessa N , Hill, Jaclyn M , Jompa, Jamaluddin , Ferse, Sebastian C A , Teichberg, Mirta
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/69135 , vital:29398 , hhttps://doi.org/10.3389/fmars.2018.00032
- Description: Habitat modification of coral reefs is becoming increasingly common due to increases in coastal urban populations. Coral reef fish are highly dependent on benthic habitat; however, information on species-specific responses to habitat change, in particular with regard to trophic strategies, remains scarce. This study identifies variation in the trophic niches of two herbivorous coral reef fishes with contrasting trophic strategies, using Stable Isotopes Bayesian Ellipses in R, along a spatial gradient of changing coral reef habitats. In the parrotfish Chlorurus bleekeri, a roving consumer, the range of δ15N and δ13C and their niche area displayed significant relationships with the amount of rubble in the habitat. In contrast, the farming damselfish, Dischistodus prosopotaenia, showed a narrow range of both δ15N and δ13C, displaying little change in niche parameters among sites. This may indicate that parrotfish vary their feeding according to habitat, while the damselfish continue to maintain their turf and invertebrate resources. Assessing isotopic niches may help to better understand the specific trophic responses to change in the environment. Furthermore, the use of isotopic niches underlines the utility of stable isotopes in studying the potential impacts of environmental change on feeding ecology.
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- Date Issued: 2018