Browsing by Department "Department of Biological Sciences"

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    A 14C and 15N study of the effects of ammonium or nitrate nutrition on carbon allocation in Triticum aestivum L. and Zea mays L
    (1991) Van der Leij, Martina
    The poor response of some plant species, e.g. wheat, to ammonium nutrition has been attributed to a diversion of carbon allocation from structural material for root extension to functions associated with the assimilation and translocation of ammonium in the root. The aim of this research was to investigate carbon allocation in response to ammonium or nitrate nutrition in wheat, an ammonium intolerant species, and maize, which exhibits ammonium tolerance. Experiments were carried out at 4mM and 12mM nitrogen feeding levels in sand and hydroponic culture respectively. pH of growth media was maintained at 6.0 to 6.5. Measurements made included shoot : root ratios, photosynthetic and root respiratory rates, plant water content, xylem sap analysis, and ¹⁴C and ¹⁵N allocation to soluble and bound nitrogen compounds, and soluble, storage and structural carbohydrates. Stunted root growth occurred in ammonium-fed wheat, which was exacerbated by increasing the NH4 concentration. No difference in growth response was evident between ammonium- and nitrate-fed maize. Photosynthetic rates of ammonium- and nitrate-fed plants within both species were similar but maize showed a 3-fold higher photosynthetic rate than wheat. Root respiration of ammonium- and nitrate-fed wheat was similar, while nitrate-fed maize appeared to have a higher root respiratory rate than ammonium-fed maize. Xylem sap analysis showed that for both species, ammonium-fed plants translocated more amino compounds and more carbon to the shoots than nitrate-fed plants, although maize appeared to have a more rapid translocation-rate than wheat. ¹⁴C allocation to nitrogenous compounds in roots of ammonium-fed plants was greater than that in nitrate-fed counterparts for both species. In wheat this increase appeared to be accommodated by a larger initial diversion of ¹⁴C to the root. In maize, reserve carbon in the root appeared to accommodate this increase. A reduction in ¹⁴C allocation to structural material in ammonium-fed plants compared to nitrate-fed counterparts was not evident in either species. ¹⁵N tracing in maize showed that significantly more nitrogen was taken up by ammonium-fed plants in comparison to nitrate-fed plants. The difference in total N between plants fed ammonium or nitrate was, however, not nearly as pronounced, suggesting that ammonium may be cycled out of the plant again. The response of wheat and maize to ammonium or nitrate nutrition is discussed independently, and suggestions for further research are made.
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    An 15N study of the effects of nitrate, ammonium, and nitrate + ammonium nutrition on nitrogen assimilation in Zea Mays L.
    (1984) Murphy, Andrew Telfer; Lewis, O A M
    A brief review of the literature on the effects of nitrate and ammonium nitrogen sources on plant growth, and the assimilation of those nitrogen sources, has been presented. A water culture technique for the growth of maize was developed. The use of a gravel rooting medium with nutrients recycling through the rooting medium, and an iron supplement in the form of ferric citrate, resulted in superior growth of nitrate-fed plants in comparison to that observed with a hydroponic growth technique and a standard Long Ashton nutrient solution. The effects of nitrogen source on plant growth, organic nitrogen and inorganic nitrogen contents, and the rates of incorporation into nitrogenous compounds were studied. The observed differences were explained with reference to the effects of the various nitrogen sources on the physiology of the plants. The experimental techniques included assays of the enzymes nitrate reductase and glutamine synthetase, whole plant growth studies, and the analysis of nitrogenous compounds of xylem exudate and those extracted from the leaf blade, leaf base, and root regions of maize plants after feeding with a nutrient solution containing nitrogen as 15N.
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    A baited remote underwater video survey of the Goukamma Marine Protected Area's ichthyofauna and a subsequent community structure comparison with the Betty's Bay, Stilbaai, and Tsitsikamma Marine Protected Areas
    (2020) Dando, Jackson Willy; Attwood, Colin
    The Goukamma Marine Protected Area (GMPA) along the South African south coast has been in existence since 1990. The MPA encompasses 40.2 km2 of subtidal ocean, 76% of which is made up of sandy substrata and the remainder of which is made of rocky reefs. The imbalance in protected habitat type ratios prompted a proposal for an extension of the MPA's seaward boundary, referred to as the new no-take zone (NNTZ), and a restructuring of its eastern boundary, referred to as the new exploited zone (NEZ). The proposed boundary changes would increase the amount of protected reef by 53% and the overall size of the MPA by 38%. Goukamma has been surveyed using controlled angling surveys (CAS) and underwater visual census (UVC) but has yet to be surveyed using baited remote underwater video (BRUV). I collected and analysed mono-BRUV data over five years to determine patterns in fish community structure in Goukamma and compare it to the pre-existing CAS and UVC data. BRUVs are less invasive and more robust than the other two survey methods and have the potential to become the predominant method of surveying ichthyofaunal communities in South Africa. This work is therefore also intended as a baseline BRUV survey. BRUVs were deployed in Goukamma from 2013 to 2017. The survey produced 328 successful deployment records between 5-41.5 m across reef and sand sites. Date, site coordinates, depth, habitat type, protection zone were used as variables to explain patterns in the fish community data. Fish abundances were recorded using the MaxN metric. MaxN counts were recorded at the instance when the highest number of individuals of each species were present in a single video frame. The deployment records were converted into a single data frame and analysed using the RStudio integrated design environment. Ariids, scyliorhinids, serranids, sparids, and triakids were the most well represented ichthyofaunal families in Goukamma. Boopsoidea inornata, Cheimerius nufar, Chrysoblephus laticeps, Galeichthys feliceps, Mustelus mustelus, Pachymetopon aeneum, Poroderma africanum, Poroderma pantherinum, and Spondyliosoma emarginatum were the most frequently observed species throughout the MPA. Habitat type was identified as the primary determinant of diversity and abundance in the GMPA using multifactor analysis of variance (ANOVA) tests (species richness: F = 191.155, P < 0.001; relative abundance: F = 96.111, P < 0.001) and Wil coxon signed rank tests (Shannon-Wiener: W = 21 102, P < 0.001; Simpson: W = 18 553, P = 4.85x10-10). The reef sites supported a higher species richness and abundance than sandy sites throughout the MPA (Tukey: q = -4.41, P < 0.001 and q = -2.12, P < 0.001, respectively). Diversity and abundance were correlated with each protection zone's predominant habitat type. Exploited zones had significantly higher diversity and abundance than protected zones as a result of the imbalance in Goukamma's protected habitat type ratio (species richness: F = 27.740, P = 7.65x10-16; abundance: F = 10.438, P = 1.51x10-6 ; Shannon-Wiener: W = 17 314, P = 4.58x10-6 ; Simpson: W = 15 896, P = 3.42x10-3 ). The NNTZ had significantly higher species richness and abundance than the NEZ (Tukey: q = 3.07, P < 0.001 and Tukey: q = 1.48, P < 0.001, respectively). The proposed changes will therefore substantially boost diversity and abundance of protected fishes in Goukamma. BRUV samples in Goukamma recorded an overall higher species richness and abundance of sparids, chondrichthyans, and other reef-associated species than CAS and UVC samples. Over 90% more chondrichthyans were recorded in the BRUV samples than by the other two methods. BRUVs are therefore considered to be a suitable replacement for CAS and UVC surveys for the monitoring of South Africa's shallow subtidal ichthyofauna. BRUV data from Betty's Bay, Stilbaai, and Tsitsikamma were available for comparison with the Goukamma data, allowing for an extensive analysis of the south coast's ichthyofaunal communities. A combined data frame of 466 successful BRUV deployments from the four study areas was created. Multi-factor ANOVA tests indicated that location (F = 27.1, P = 1.00x103 ), depth zone (F = 17.4, P = 1.00x103 ), protection status (F = 23.1, P = 1.00x103 ), and habitat type (F = 91.8, P = 1.00x103 ) were all significant in determining community structure among the study areas. Reef sites had higher species richness and abundance than sand sites and species richness and abundance decreased from east to west along the south coast according to subtropical subtraction. However, the presence of an additional habitat type in Betty's Bay, namely kelp forests, resulted in it having a higher species richness and abundance than Stilbaai to the east. Betty's Bay's community structure was the least similar to the other three study areas as a result of the localised kelp forests in and around the MPA. These kelp forests shifted Betty's Bay's community structure away from the sparid-dominance observed in Stilbaai, Goukamma, and Tsitsikamma and towards a carangid- and scyliorhinid-dominance. However, cold-water associated sparids such as Pterogymnus laniarius were more abundant in Betty's Bay than the other study areas. Almost 80% of the species recorded among the study areas were represented in two or more of the four MPAs, indicating a good degree of redundancy of protection along the south coast within the depth ranges sampled. These data suggest that the Cape south coast is adequately protected from the perspective of fish representation. Review of the De Hoop, Sardinia Bay, and Bird Island MPAs should be conducted to further examine complementarity and redundancy of protection along South Africa's south coast.
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    A biophysical, biochemical and serological study of selected members of the enteroviruses
    (1969) Smith, Martin Sidney
    The purpose of this investigation was to study the biophysical and biochemical properties of some of the enteroviruses. Previous work in this laboratory on several members o.f this large sub-group of the Picornaviruses had emphasised the importance of a more detailed examination of some of the surface properties of representative strains of enteroviruses, by currently available techniques.
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    A Braun-Blanquet survey of some Cape-forest vegetation
    (1974) Campbell, Bruce Morgan
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    A brief history of marine bio-invasions in South Africa
    (2009) Griffiths, C L; Mead, A; Robinson, T B
    Marine species have been introduced continuously into South Africa for more than 400 years, since the arrival of the first European explorers. Various waves of introduction can be identified over this period, each associated with a different mix of vectors. Early wooden vessels carried specialized wood-boring species, a rich external fouling community, plus semi-terrestrial species associated with dry ballast. Modern steel vessels continue to import fouling species, despite the use of anti-fouling paints, and may ply new routes, bringing additional introductions from novel locations. More modern waves of introduction are associated with use of ballast water and with marine aquaculture. Research on marine bio-invasions in South Africa has a short history, marked by a rapid rate of discovery of introductions. Some 86 marine species are currently regarded as introduced to the region, with a further 39 considered cryptogenic, but this number is increasing rapidly. Moreover, many taxa and regions still remain inadequately explored, indicating that the current list remains far from complete. The reasons for under-reporting of introduced populations are discussed and include lack of sample coverage, misidentification of aliens as native species and erroneous redescriptions of aliens as new, indigenous species. However, the lack of taxonomic expertise across large sections of the biota remains the greatest impediment to progress.
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    A camera trap assessment of factors influencing leopard (Panthera pardus) habitat use in the Nouabalé-Ndoki National Park, Republic of Congo
    (2018) Mavinga, Franck Barrel; O'riain, Justin; Mann, Gareth; Breuer,Thomas
    Leopards (Panthera pardus) are faced with increasing levels of anthropogenic pressure resulting in population declines across much of their historical range. While there is relatively limited knowledge of leopards occurring in African rain forests, their abundance and distribution is assumed to be impacted by a combination of several anthropogenic factors, most notably loss of prey and habitat conversion. In this study I used a long-term camera trap array that forms part of the Tropical Ecology, Assessment and Monitoring (TEAM) project - Terrestrial Vertebrate (Camera Trapping) Monitoring Protocol, to estimate the species richness of mammals, the relative abundance of leopard prey species and leopard habitat use in the Nouabalé-Ndoki National Park (NNNP) in the Republic of Congo. I investigated the impact of different environmental and anthropogenic factors on leopard occurrence at two camera trap arrays (a northern and southern cluster) within the NNNP using occupancy modelling. While there were no significant differences in mammalian species richness between the two clusters there was a higher relative abundance of the preferred prey species of leopards in the northern cluster. A total of 106 leopard photographic events were recorded across all camera traps and all survey years. The top occupancy model produced an average probability of site use (ψ) over all sites of 0.52 ± 0.14 (SE). The covariate specific β-coefficient estimate suggests that leopard occurrence and detectability were positively correlated with both the relative abundance of the blue duiker (Philantomba monticola) and the distance to the nearest river (β =0.062 ± SE 0.053 and 6.55 ± SE 10.84, respectively). Therefore there was no support for the prediction that the probability of leopard habitat use increases with a higher relative abundance of all potential prey species, nor was there support for the prediction that leopard habitat use would be higher further away from human settlements (β =3.42 ± SE 2.94). 2 Leopard habitat use was higher in the southern cluster which may be linked to the denser understory that would provide greater cover which is important for improved hunting success in leopards. Together, these results suggest that both the prey species and leopards appear to be thriving within the NNNP with limited evidence of anthropogenic impacts despite an increase in commercial logging and the itinerant bushmeat hunting in the peripheral area. It would be worth expanding the existing camera trap arrays to cover a greater spatial extent within NNNP and hence allow for a more detailed analysis of edge effects and to detect the potential impacts of anthropogenic activities which are predicted to increase in selected villages in the periphery of the park.
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    A case study from the southern Cape linefishery 2: Considering one’s options when the fish leave
    (2017) Gammage, Louise C; Mather, Charles
    Fishers in the small-scale, commercial linefishery in the southern Cape, South Africa, are exposed to variability and change in the marine social-ecological system of which they are a part. Faced with multi-scalar changes within this complex system, fishers employ a wide range of strategies in reaction to change. As part of a broader study of stressors that bring about change in these systems, this contribution examines the fishers’ responses to these changes and is based on a participant-led, semi-structured interview process of skippers/boat owners, crew, processors and spouses/partners, in six communities in the southern Cape region, and has been supplemented with appropriate secondary data. The results are discussed using a resilience framework. The data were initially considered thematically by stressor, but results identified that a place-based analysis was equally important. Three major groupings were identified: (1) fishers who adapt and show clear business-orientation, (2) fishers who cope, and (3) fishers who react and are thus caught in a poverty trap. In addition to place-specific history, local feedback loops and indirect effects need to be better accounted for to understand these responses to change at various scales. The results of this study are expected to contribute to the basis of scenario planning in the region.
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    A change of the seaward boundary of Goukamma Marine Protected Area could increase conservation and fishery benefits
    (2009) Götz, Albrecht; Kerwath, Sven E; Attwood, Colin G; Sauer, Warwick H H
    Goukamma Marine Protected Area (MPA) on the South African temperate South Coast has been shown to be effective in maintaining a spawning stock of roman, Chrysoblephus laticeps (Sparidae). The larval ecology and the oceanographic conditions in the area suggest a good potential for the enhancement of roman stocks outside the reserve through larval dispersal. A high rate of illegal fishing just inside the seaward boundary of the MPA could severely compromise its function. We suggest that a change of the seaward boundary of the reserve to coincide with a latitudinal line could increase its function as a harvest refuge for resident reef fishes such as roman, facilitate voluntary compliance and monitoring and prosecution of illegal fishing without a significant negative impact on the commercial linefishing fleet in the area. Simple adjustments such as the one proposed here could be attempted at a number of South African MPAs as they would be beneficial to achieve fishery and conservation goals alike.
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    A comparison of rapid bioassessment protocols used in 2 regions with Mediterranean climates, the Iberian Peninsula and South Africa
    (2006) BONADA, NÚRIA; DALLAS, HELEN; RIERADEVALL, MARIA; PRAT, NARCÍS; DAY, JENNY
    Abstract. The ability of 2 Rapid Bioassessment Protocols (RBPs) to assess stream water quality was compared in 2 Mediterranean-climate regions. The most commonly used RBPs in South Africa (SAprotocol) and the Iberian Peninsula (IB-protocol) are both multihabitat, field-based methods that use macroinvertebrates. Both methods use preassigned sensitivity weightings to calculate metrics and biotic indices. The SA- and IB-protocols differ with respect to sampling equipment (mesh size: 1000 lm vs 250-300 lm, respectively), segregation of habitats (substrate vs flow-type), and sampling and sorting procedures (variable time and intensity). Sampling was undertaken at 6 sites in South Africa and 5 sites in the Iberian Peninsula. Forty-four and 51 macroinvertebrate families were recorded in South Africa and the Iberian Peninsula, respectively; 77.3% of South African families and 74.5% of Iberian Peninsula families were found using both protocols. Estimates of community similarity compared between the 2 protocols were .60% similar among sites in South Africa and .54% similar among sites in the Iberian Peninsula (Bray-Curtis similarity), and no significant differences were found between protocols (Multiresponse Permutation Procedure). Ordination based on Non-metric Multidimensional Scaling grouped macroinvertebrate samples on the basis of site rather than protocol. Biotic indices generated with the 2 protocols at each site did not differ. Thus, both RBPs produced equivalent results, and both were able to distinguish between biotic communities (mountain streams vs foothills) and detect water-quality impairment, regardless of differences in sampling equipment, segregation of habitats, and sampling and sorting procedures. Our results indicate that sampling a single habitat may be sufficient for assessing water quality, but a multihabitat approach to sampling is recommended where intrinsic variability of macroinvertebrate assemblages is high (e.g., in undisturbed sites in regions with Mediterranean climates). The RBP of choice should depend on whether the objective is routine biomonitoring of water quality or autecological or faunistic studies.
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    A comparison of some potential indicators of desiccation-tolerance in 2 Poikilochlorophyllous Xerophyta species and Homiochlorophyllous Craterostigma wilmsii
    (2002) Brown, Carly; Farrant, Jill M
    Three possible indicators of desiccation-tolerance in ang10sperms: sucrose accumulation and hexose sugar flux, an increase in hexokinase activity, and accumulation of LEA-like proteins, were investigated and compared during dehydration between two moncotyledonous poikilochlorophyllous resurrection angiosperm species; Xerophyta schlecterii and Xerophyta humilis, and a dicotyledonous homiochlorophyllous resurrection species, Craterostigma wilmsii. Comparisons were also made with Xerophyta viscosa, using data from Whittaker et al, (2001). Soluble sugar concentrations and hexokinase activities were also examined during rehydration of the three species. Sucrose was accumulated during dehydration in all species examined. However, C. wilmsii had completed sucrose accumulation by the intermediate stages of drying, whereas Xhumilis exhibited a late accumulation. It was not clear if Xschlecterii exhibited late sucrose accumulation due to high standard deviations in the results. C. wilmsii accumulated higher sucrose levels than the two poikilochlorophyllous species. During rehydration the sucrose concentrations dropped in all three species, and was probably being used as an energy source for the resumption of metabolism. Glucose and fructose concentrations were relatively constant during dehydration in all three species, and did not appear to be contributing greatly to sucrose accumulation. This was further confirmed by the low levels of activity of hexokinase found in all three species during dehydration and rehydration, which suggests that the channelling of glucose and fructose into sucrose biosynthesis is not being upregulated during dehydration. C. wilmsii had an increased level of hexokinase late in dehydration, that may have been in preparation for the rapid rehydration experienced by this homiochlorophyllous species, where hexokinase would need to rapidly channel glucose and fructose into metabolism. There was not an increase in activity at the period of highest sucrose accumulation in this species. The activity of hexokinase was relatively constant throughout dehydration and rehydration for Xschlecterii, as it was for Xhumilis. Glucose and fructose levels dropped slightly in C. wilmsii during rehydration but remained relatively constant in the two poikilochlorophyllous species. The presence of LEA-like proteins was found in all three species, although the bands were very faint for X viscosa and Xhumilis. In Xschlecterii the bands were clear in the dehydrated leaf sample, but were faint or absent in the hydrated sample. It is possible that the proteins in this species were upregulated or induced by drying. A protein common to all three species in dehydrated and hydrated samples was observed between the 22.5 kDa and the 15.3 kDa molecular markers.
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    A contribution to understanding the primary moult of birds
    (2023) Scott, Tanya; Underhill, Leslie; Erni Birgit
    Moult is an essential component of the annual cycle of birds, along with breeding, and, if migratory, migration. The leading statistical model for the analysis of primary moult is the Underhill-Zucchini moult model. It estimates moult parameters (duration, the mean start date and its standard deviation). An objective of this thesis was to assemble all published results which had used the UnderhillZucchini moult and to examine the resulting database for patterns in the timing, duration and synchronisation of moult. A total of 242 analyses of 136 species were found. The initial analysis of the database generated two observations: firstly, that latitude played an important role in determining patterns of primary moult, and, secondly, that the available data were latitudinally, spatially across continents, and taxonomically not representative. These gaps in knowledge were too large to rectify within the confines of a single PhD thesis. The preliminary chapters of the thesis added 18 analyses, for 11 species, and have made a contribution towards representativity. Two of the preliminary chapters make substantive contributions to the methods of undertaking statistical studies of moult. A new moult index, the Relative Duration Index, is introduced. Moult studies are frequently undertaken by combining datasets collected in different years (or different places). This thesis contains the first practical application of a proposed method to identify which of the individual datasets have a large influence of the estimates of the moult parameters. Nine analyses extended the latitudinal range of studies southwards and were based on datasets assembled in New Zealand. These are the first analyses of primary moult using the UnderhillZucchini moult model from this country. For seven species, this thesis undertakes moult studies of a species in both its original country, the United Kingdom, and the country into which it had been introduced, New Zealand. These are the first analyses of primary moult of this kind. Preliminary patterns of moult strategies are discussed. Critical gaps in our understanding of primary moult are identified. Priorities for fieldwork and analysis are described in order that key gaps are filled and a global review of primary moult can be undertaken.
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    A decision-making framework for restoring riparian zones degraded by invasive alien plants in South Africa
    (2005) Holmes, P M; Richardson, D M; Esler, K J; Witkowski, E T F; Fourie, S
    Riparian habitats in many parts of South Africa are severely degraded by invasive alien plants, especially trees. These invasions reduce water yields from catchments and affect riverine functioning and biodiversity. Initiatives are under way countrywide to clear alien plants from watercourses and surrounding catchments. Current understanding of key processes that regulate riparian functioning and define options for restoration is rudimentary. We review the impacts of riparian invasions and identify factors limiting the recovery of natural vegetation following alien clearance. We propose a framework of strategic interventions for optimizing restoration success. The framework identifies abiotic and biotic barriers to restoration at the scales of catchments and local reaches. In highly transformed catchments, interventions at the reach scale may fail if important barriers at the catchment scale are not addressed. The extent to which propagule supply and microsite conditions inhibit vegetation recovery is unknown. We also know little of the relative importance of dispersing vegetative propagules, dispersing seeds and soil-stored seed banks in vegetation dynamics, particularly after severe disturbances such as dense invasion by alien plants. The importance of geomorphological and hydrological factors in mediating recovery of riparian vegetation has not been adequately explored for all climatic areas in South Africa. More research is needed to determine the influence of different alien species and clearing treatments on the recovery of riparian vegetation. The literature strongly suggests that in highly alien-transformed catchments, the re-introduction of riparian species is required to promote recovery and suppress re-invasion. However, such interventions are unlikely to be widely implemented unless the cost: benefit ratios are favourable.
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    A genetic perspective on leopard (Panthera pardus) conservation units across southern Africa
    (2021) Thacker, Thomas M; Bishop, Jacqueline M; Naude, Vincent N
    Conservation units are a tool to guide policy such that conservation goals can be achieved. These units should ideally synthesise a wide array of data – genetic, ecological, demographic – to identify the appropriate scales at which conservation actions can then be directed. Despite being the most widespread of all felids in Africa, and facing numerous threats across its range, it has been proposed that the entirety of southern Africa be considered one conservation unit for leopards (Panthera pardus pardus). This proposal does not take into consideration the likelihood of existing population genetic structure across an increasingly fragmented landscape. Further complicating regional leopard conservation is the variability in conservation policies among the geopolitical leopard-range states. Within this single proposed conservation unit, the patchwork of different legislation does not support a unified policy for leopard conservation. Using a population genetic perspective, this study explores and tests the values and shortcomings of southern Africa as a single conservation unit, and explores the importance of leopard range states within the context of conservation units. Parallel investigations of leopard microsatellite genotype data within the framework of a genetic population study spanning eight countries across southern Africa were carried out. This study presents consilient evidence supporting the finding that southern Africa contains six clusters of unique genetic lineages, and as such does not constitute a single genetic unit. Furthermore, it is shown here that the spatial genetic structure that exists does not correlate with the separate geopolitical range states. Leopard range states within southern Africa instead capture varying levels of unique genetic structure and thus are not of equal value with respect to the conservation of genetic lineages. These findings have several implications for leopard conservation across the region. While the data presented here specifically consider a genetic element of conservation units, they do suggest shortcomings in adopting either the entirety of southern Africa as a single unit or separate geopolitical range states as conservation units. The variability in leopard conservation policy across southern Africa is unlikely to sufficiently protect their existing regional genetic structure. If conservation units are indeed a tool to guide conservation policy, then the southern Africa unit for leopards is potentially less effective than a smaller unit whose spatial scale more accurately captures the discrete variation in population genetic structure. Genetic diversity and population structure is an important component of conservation units and should not be neglected. Currently, however, an appropriate framework allowing for conservation policy to be informed at the necessary scale does not exist; although the establishment of Transfrontier Conservation Areas speaks to the growing acknowledgement that conservation needs to evolve beyond the historical confines of geopolitical range states. The evidence presented here further supports the need for a rethinking of existing policy structures.
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