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ZOOLOGY 300 RESEARCH PROJECTS ON OFFER 2016
1. Microplastics
Microplastics, small plastic particles with an upper size limit of 5 mm, may have
“potential ecological and human health risks” when associated with marine organisms.
For example, they may become vectors for the transportation of toxic chemicals,
originating from either the plastic item (additives, monomers and by-products) or the
surrounding marine environment (persistent organic pollutants). Thus, when ingested
by various fauna, there is a potential for toxic compounds to bio-magnify through the
food-web. Although investigations into the extent and effect of microplastic pollution
have increased dramatically, knowledge is still scarce, including the impact these
microplastics may have on human health and food consumption.
A recent study conducted at Rhodes University investigated the extent of microplastic
pollution along the south eastern coast of South Africa. Results from this study suggest
microplastic pollution along the South African coast is in the same range as more
developed countries in the Northern Hemisphere. In addition, this study highlighted
that microfibres represent a significant source of pollution, possibly originating from
the breakdown of synthetic garments during the washing process. This study served
as the first step, which is to identify and evaluate the extent of the problem. Thus, the
next step will be to investigated the effect this problem may have on marine organisms,
especially economically important species consumed by the South African population.
o Title: Impact of sampling method and spatial heterogeneity on microplastic
densities on two South African beaches.
o Title: The extent of microplastic contamination in the tissue of the alien and
native mussel, Mytilus galloprovincialis and Perna perna respectively.
Supervisor: Dr H.A. Nel and Co-supervisor: Prof. P.W. Froneman
2. Ephemeral pond ecology
Ephemeral ponds are an essential habitat for a number of unique invertebrates and
amphibians and represent important foraging grounds for a variety of birds (O’Niell
and Thorp 2014). Many of these systems are often ecologically degraded due to land
use activities, mainly commercial agriculture, and freshwater abstraction. Despite their
ecological importance, for the greater majority of these systems we have a poor
understanding of their ecosystem functioning. Studies conducted in the northern
hemisphere, however, indicate that the food web dynamics within these systems are
strongly linked to the hydroperiod (wet/dry phase), dimension/volume of pond and the
diversity of invertebrates within these systems (O’Niell and Thorp 2014). Overall,
larger ponds with high insect diversity are characterized by more complex trophic
structures than those systems dominated by crustaceans (O’Niell and Thorp 2014).
The proposed research project will assess the temporal variability in selected physicochemical and biological variables in three ephemeral ponds in the immediate vicinity
of Grahamstown. Physico-chemical samples will be collected using a portable probe
and biological samples using nets. Sampling will be conducted on a monthly basis to
assess the link between the hydroperiod and the food web structure of these systems.
Two projects are on offer.
References
O’Niell BJ, Thorp JH (2014). Untangling food-web structure in an ephemeral
ecosystem. Freshwater Biology 59: 1462-1473
Supervisors: Professor PW Froneman and Mr T Dalu
3. Ecosystem engineers
The sand prawn Calianassa kraussi has been identified as an important systems
engineer within temporarily open/closed estuaries. Bioturbation generated by the sand
prawn contributes to decreased biomass of both the microphytobenthic algae and
epifauna. This project will investigate the influence of the sand prawn burrowing
activities on the macrobenthic community structure within a temporarily open/closed
Eastern Cape estuary during summer and winter. Two projects are on offer
Supervisor: Prof PW Froneman
4. Macrobenthic community structure in a freshwater deprived estuary.
Long term data sets on the spatial and temporal patterns in the invertebrate faunal
community structure in southern African estuaries are lacking. This study will
investigate the spatial patterns in the macrofauna within four different soft sediment
estuarine habitats within the permanently open Kariega Estuary situated along the
Eastern Cape coastline. Data collected during the present study will be compared to
a similar study conducted within the estuary two decades previously. Two projects
are on offer
Supervisor: Prof PW Froneman
THIRD YEAR (Zoology or Entomology):
1. Frog predation on the biocontrol agent, the flea beetle Lysathia sp. (Coleoptera: Chrysomelidae),
released against the Parrot's Feather (Myriophyllum aquaticum)
Biocontrol agents are released against various invasive plants, and for the agent to be effective, they
need to eventually cause the plant to die, through their herbivorous actions, whilst avoiding predators.
In some instances, although the agent has been found to be effective in laboratory conditions, natural
conditions present the agents with novel problems. Frogs are prolific predators on invertebrates in
the natural environment and this study aims to investigate whether the presence of the painted reed
frog Hyperolius marmoratus verrucosus significantly reduces the population numbers of the biocontrol
agent, the flea beetle Lysathia sp. (Coleoptera: Chrysomelidae), released against the Parrot's Feather
(Myriophyllum aquaticum).
Proposed methods

Controlled environment experiments will be conducted with
four experimental setups: (1) With three adult H. m.
verrucosus and the biocontrol agent, (2) with three
subadult H. m. verrucosus and the biocontrol agent, (3)
only the biocontrol agent, (4) no biocontrol agent or
frogs (control setup).

Beetle population numbers will be counted after two
weeks, and analyses of the effect of frog predation on
the population numbers will be determined.
References
Du Preez, L. H., Carruthers, V., & Burger, M. (2009). A complete guide to the frogs of southern Africa.
Struik Nature.
Snyder, W. E., & Ives, A. R. (2001). Generalist predators disrupt biological control by a specialist
parasitoid. Ecology, 82(3), 705-716.
5. Snake diversity is lower in fields that have been burned recently compared to
an unburned area. (Luke Kemp has already taken this project)
Globally, reptile population numbers have been declining, reminiscent of the recent
decline in amphibian populations. An understanding of the factors that lead to
population declines in reptiles is crucial to mitigate future declines. Diversity and
abundance of animals have been shown to be reduced when a habitat has been
burned. In fire-prone biomes such as the fynbos biome and the grassland biome,
populations of reptiles experience periodic fires that destroy the habitat, including the
predatory snake species. However, the ultimate reason for the low abundance in
predators may be not entirely due to the lack of shelter in a burned area, but may be
due to the low abundance of prey items. Snakes locally found in the Grahamstown
area are either carnivorous, feeding on rodents and frogs, or are specialised eggeaters. In a burned area, we expect that the snake diversity in a burned area will be
lower than in an unburned area, due to the low abundance of prey items.
Proposed methods
o Snake diversity and abundance will be measured through collection using
pitfall traps during the months of November 2015 to April 2016, and a
correlation between time since the burn and abundance will be investigated.
o Comparative abundance of snakes in burned and unburned fields will be
investigated.
References
Gibbons J.W., Poppy S., Winne C. T. et al. (2000) The global decline of reptiles, déjà
vu amphibians. Bioscience 50, 653–66.
Gorissen S., Mallinson J., Greenless M., Shine R. (2015) The impact of fire regimes
on populations of an endangered lizard in montane south-eastern Australia. Austral
Ecology. 40(2): 170-177
Supervisor: Dr Shelley Edwards (SE), Office S19, Biological Sciences Building, Email:
[email protected]; Tel: 046-603-8086
6. Convergence in the angularity of snouts in burrowing reptiles
In an arid region, such as southern Africa, many lizards and snakes have adapted to
sheltering in soil to escape predators or the heat of the day. Many reptiles dive headfirst into the soil, instead of digging their way in, and as such have evolved unique,
shovel-shaped snouts to facilitate entry into the substrate. Due to the resistance of the
soil particles, it is hypothesized that the angle of the snout would be optimally effective
in a range of between 45° and 60°. This project aims to investigate whether there is a
similarity in the angle of the snout of various burrowing lizards, and therefore to show
that reptiles have evolved convergent morphologies in response to the same selective
pressure.
Proposed methods
o Ten species of borrowing or diving reptiles will be used, namely Meroles
anchietae, Meroles cuneirostris, Acontias meleagris, Acontias gracilicauda,
Prosymna sundervallii, Prosymna bivittata, Gerrhosaurus skoogi, Typhlacontias
sp., Scelotes anguineus, Scelotes bipes.
o Photographs of five individuals of each species will taken at the Bayworld museum
in Port Elizabeth. Angles of the snouts will be measured on the photographs and
statistics will be used to investigate the convergence of angles between species.
References
Hanken, J. (1993). The skull, volume 3: Functional and evolutionary mechanisms (Vol.
3). University of Chicago Press.
Etheridge, R. (2000). A review of lizards of the Liolaemus wiegmannii group
(Squamata, Iguania, Tropiduridae), and a history of morphological change in the sanddwelling species. Herpetological Monographs, 293-352.
Supervisor: Dr Shelley Edwards (SE), Office S19, Biological Sciences Building, Email:
[email protected]; Tel: 046-603-8086
7. Painted reed frog Hyperolius marmoratus verrusosus (Hyperoliidae) abundance
and distribution around Grahamstown is tied to particular habitats
The Painted reed frog Hyperolius marmoratus verrusosus is a relatively common
species occurring along the coastal regions of the Eastern Cape and Western Cape
Provinces. It is often found around water bodies, sheltering amongst reeds. However,
as the Eastern Cape is a region that receives rainfall year-round, as opposed to the
winter-rainfall regime of the Western Cape, ephemeral puddles and water bodies are
often formed in vegetation in the Eastern Cape. The frogs may be utilising these nonpermanent water bodies, as well other types of vegetation (such as arum lilies) for
shelter. This project aims to investigate the habitats that the painted reed frogs are
associated with in the Grahamstown area, and to estimate the density of frogs in
various types of habitats, at various times of the year.
Proposed methods
o Frog calls will be recorded at various points around Grahamstown during twilight
and early evening times for a period of three months. In addition, information on the
weather preceding, and during, sample days will be noted. The particulars of the
habitat at each sample site will be recorded.
o Frog density will be determined through identification of number of frogs calling at
a particular location.
o Frog density (i.e. number of frogs calling) will be correlated with habitat
characteristics, as well as with climatic (weather) characteristics.
References
Du Preez, L. H., Carruthers, V., & Burger, M. (2009). A complete guide to the frogs of
southern Africa. Struik Nature.
Pellet, J., & Schmidt, B. R. (2005). Monitoring distributions using call surveys:
estimating site occupancy, detection probabilities and inferring absence. Biological
Conservation, 123(1), 27-35.
Pierce, B. A., & Gutzwiller, K. J. (2004). Auditory sampling of frogs: detection efficiency
in relation to survey duration. Journal of Herpetology, 38(4), 495-500.
Please note that similar projects can be offered to investigate the density of
other frogs such as the raucous toad (Amietophrynus rangeri), bronze caco
(Cacosternum nanum), and Boettger’s caco (Cacosternum boettgeri).
Supervisor: Dr Shelley Edwards (SE), Office S19, Biological Sciences Building, Email:
[email protected]; Tel: 046-603-8086
Zoology 3 2016
Note: Students are encouraged to bring their own ideas for projects; however, all students
must do some reading around any potential project prior to booking an appointment with a
potential supervisor to discuss topic selection.
1. Intertidal amphipods of the Eastern Cape
Supervisor: Nicole Richoux
A variety of amphipods flourish in the intertidal region of the rocky shore, as they can utilise the
macroalgae as food and/or shelter. Students can design questions to investigate amphipod ecology
at different sites in the Eastern Cape.
Starter references
Buschmann (1990) Intertidal macroalgae as refuge and food for Amphipoda in central Chile.
Aquatic Botany 36:237-245
Chavanich and Wilson (2000) Rocky intertidal zonation of gammaridean amphipods in Long
Island Sound, Connecticut. Crustaceana 73:835-846
Skadsheim (1983) The ecology of intertidal amphipods in the Oslofjord. Distribution and
responses to physical factors. Crustaceana 44: 225-244
2. Organic content of the fecal pellets of estuarine consumers
Supervisor: Nicole Richoux
Aquatic invertebrates represent important vehicles for the uptake and transformation of
energy and nutrients. For example, the production of fecal pellets can represent an enormous
transfer of organic material from the water column to the benthos over short temporal scales.
This flux of material, in turn, has important ramifications for the availability and quality of
food in the benthos, but limited information exists for shallow coastal systems. In this study,
a student can carry out field collections of different estuarine organisms with the intention of
collecting naturally produced fecal pellets. These samples will be analysed for their organic
contents to assess the contribution and quality of detritus settling to the benthos in estuarine
systems.
Starter references
Turner (2002). Zooplankton fecal pellets, marine snow and sinking phytoplankton blooms.
Aquatic Microbial Ecology 27:57-102
Wotton and Malmqvist (2001). Feces in aquatic ecosystems. BioScience 51:537-544
3. Temporal variability of suspended particulate material over a tidal cycle
Supervisor: Nicole Richoux
Various marine invertebrates are dependent on suspended particulate material (SPM) as their
food source. Because their physical environment changes extensively through time,
particularly over tidal cycles, animals are subject to rapid changes in the quality of their food
sources. In this study, students will determine changes in SPM characteristics during a tidal
cycle. Potential measurements to be taken include: chlorophyll a concentrations, dry mass,
organic content, inorganic content and possibly stable isotope ratios (if funding permits).
Starter references:
Bodineau, L., Thoumelin, VB & Wartel, M (1998). Tidal time-scale changes in the
composition of particulate organic matter within the estuarine turbidity maximum zone in
the macrotidal Seine Estuary, France: the use of fatty acid and sterol biomakers.
Eastuarine, Coastal & Shelf Science 47: 37-49.
Danovaro, R & Fabiano, M (1997). Seasonal changes in quality and quantity of food
available for benthic suspension-feeders in the Golfo Marconi (north-western
Mediterranean). Eastuarine, Coastal &l Shelf Science 44: 723-736.
4. Faunal diversity associated with rocky shore macroalgae, mussel beds and/or
polychaete beds
Supervisor: Nicole Richoux
Some organisms represent important habitat for other organisms. Rocky shore macroalgae,
mussels and tube-building polychaetes represent a few potential habitats for organisms. Students
will assess the biodiversity associated with each of these habitats.
Starter references
Koivisto ME, Westerbom M (2010) Habitat structure and complexity as determinants of
biodiversity in blue mussel beds on sublittoral rocky shores. Mar Biol 157:1463–1474
Lintas, C. and Seed, R. (1994) Spatial variation in the fauna associated with Mytilus edulis on
a wave-exposed rocky shore. Journal of Molluscan Studies, 60, 165–174.
5. Drifting components in a river/estuary continuum
Supervisor: Nicole Richoux
A variety of organic and inorganic material is transported through rivers and estuaries.
Students will design a field study to quantify the nature and amount of drift transported
through a river.
Starter references
Shannon et al. 1996. Organic drift in a regulated desert river. Can. J. Fish. Aquat. Sci.
53:11360-1369
Eckblad et al. 1984. Allochthonous drift from backwaters to the main channel of the
Mississippi River. American Midland Naturalist 111(1): 16-22
Andersson E, Nilsson C 2002. Temporal variation in the drift of plant litter and propagules in
a small boreal river. Freshwater Biology 47:1674–1684
6. Life in the intertidal – does vertical position in the rocky intertidal affect the
condition of grazing or suspension-feeding invertebrates
Supervisor: Nicole Richoux
The rocky shore is a highly variable environment inhabited by a variety of invertebrate
species. Tidal changes are key structuring features for the physiology and ecology of these
organisms. A student will design a study to investigate the effects of vertical position on the
condition (e.g. using condition factors, gonado-somatic index, morphology, etc.) of several
species of interest.
Starter reference:
Gagné F, Burgeot T, Hellou J, St-Jean S, Farcy É, Blaise C (2008) Spatial variations in
biomarkers of Mytilus edulis mussels at four polluted regions spanning the Northern
Hemisphere. Environmental Research 107:201–217
Zoology 3 Projects: Supervisor Prof. A. Craig
Fiscal Shrike territorial behaviour
For several years we have monitored Fiscal Shrike territories on the campus. Although the
birds change, territory sites tend to remain constant. Colour-ringed individual birds can be
observed throughout the year; males and females show differences in their defence of the
territory. Birds will be caught and ringed where needed. Two students can be involved in
this project.
Soobramoney, S, Downs, CT, Adams, NJ. 2004. Territorial behaviour and time budgets of
the fiscal shrike Lanius collaris along an altitudinal gradient in South Africa. African Zoology
39: 137-143.
Birds at nectar feeders
At several households in Grahamstown, nectar feeders are in regular use. Provision of
extra food for wild birds may make them dependent on these food sources, changing their
distribution and foraging patterns. Camera traps and ringing can be used to clarify how
regularly individual birds visit a particular site. Two students can be involved in this project.
Brockmeyer, T, Schaefer, HM. 2012. Do nectar feeders in Andean nature reserves affect
flower visitation by hummingbirds? Basic and Applied Ecology 13: 294-300.
Birds at garden feeders
Seed (and often bread, sometimes also fruit) are provided regularly at many homes. As with
nectar feeders, this may make birds dependent on these food sources. Camera traps and
ringing can be used to clarify how regularly individual birds visit a particular site. Two
students can be involved in this project.
Galbraith, JA, Beggs, JR, Jones, DN, Stanley, MC. 2015. Supplementary feeding restructures
urban bird communities. Proceedings of the National Academy of Sciences E2648-2657
Supervisor: Prof A Hodgson
Distribution, density and population structure of the Shaggy Sea Hare Bursatella leachii
(Gastropoda) in the Knysna Estuary (This project can be undertaken by up to two students)
The shaggy sea hare is a shell-less mollusc that appears to be particularly abundant in the Knysna
Estuary. Furthermore, preliminary investigations have revealed that it is present throughout the
year. Because of its abundance it is possible that it plays an important role in the ecology of the
estuary. As a first step towards studying the biology of this species it is necessary to determine some
basic information on this gastropod. The aims of this project, therefore, are to record the density of
this sea hare at different sites within the Knysna estuary and by measuring specimens also look at its
population size structure.
Note: this project will require the ability to snorkel in shallow water and therefore student should
have their own snorkelling equipment and a wet suit.
The dining habits of the Shaggy Sea Hare Bursatella leachii (Gastropoda)
The shaggy sea hare can be found roaming over soft sediment and algae. They are said to be algal
grazers, but it is not known for certain. The aim of this project would be to use gut contents analysis,
faecal analysis and perhaps stable carbon isotope ratios to determine what these gastropod
molluscs are actually feeding on.
Distribution, density and population structure of the invasive gastropod snail Myosotella myosotis
(Mollusca: Ellobiidae) in the Knysna Estuary (A project for up to two students)
Myosotella myosotis is a snail found in salt marsh vegetation of estuaries. Herbert (2012) records it
presence in the Knysna estuary which is part of the Garden Route National Park. Casual observations
(Hodgson pers. obs.) suggest that it is very abundant but there is no quantitative data on its density,
population structure and distribution within the intertidal and within the estuary. The aims of this
project are to provide some fundamental data on this snail within the salt marshes of the Knysna
estuary. It may also be possible to establish a laboratory population to determine growth rate and
fecundity.
Lead-in Reference
Herbert, D.G. 2012. Myosotella myosotis (Mollusca: Ellobiidae) - an overlooked but well-established
introduced species in South Africa. African Journal of Marine Science 34(3): 459-464.