Coral Reef Ecology Laboratory - Professor Mark Ian McCormick









Mark McCormack Reef Fish Ecology

Past students (since 2004)

Honours

 

Lucy Holmes - Effect of boat noise on juvenile fishes

Co-supervisor: Maud Ferrari (Univ Saskatchewan), Steve Simpson (Univ Exeter)

The impact of noise pollution on marine soundscapes is of great importance as we increase the anthropogenic noise in the oceans. The effect this has on individuals could alter their survival and in turn affect whole populations and communities. This proposed project expands on these studies and examines the influence of boat noise on settlement and community development of tropical fish and its effect on how prey respond to a predator threat, which could translate into probability of survival of recruits in a noisy environment.

 

 

Katy Korkill - Interference competition indirectly and directly affects body shape

Principal supervisor: Dr Maud Ferrari (Univ Saskatchewan)

This study examined how the intensity of density-dependent intraspecific competition affected the growth dynamics of a social coral reef fish, Pomacentrus moluccensis (Pomacentridae), and what trade-offs were associated with modifying their body plan, with respect to either size, shape, or both.


 
 

 

Ana Del Callejo -  Efficacy of biochronologies for rapidly growing tropical fishes

Co-supervisor: Mark Meekan, Adam Rountrey (AIMS)


Growth is a key factor determining success and survival of all organisms. Understanding the link between growth and environmental fluctuations is key component of fisheries management.  Luckily, increments in the hard parts of marine organisms can provide long-term chronologies of growth analogous to tree-rings. This project involves using the latest biochronology techniques to experimentally determine how well fish growth reflects their environment.
 

 

Georgia McGee -  Aerobic Metabolism and the Influence of Climate Change on the Predator Defence Strategies of Pufferfishes

Principal-supervisor: Tim Clark (AIMS)

The majority of coral reef fishes rely on speed and manoeuvrability to avoid predation. Some reef fishes, such as the pufferfishes, have developed more extreme anti-predator responses. In addition to the spines covering much of their body, this group of fish are renowned for their ability to inflate themselves to several times their normal size by frantically gulping water into their stomachs. Being notoriously slow swimmers, an important part of the pufferfish defence is to increase their size in the hope that they become too large for predators to swallow. Whilst the metabolic consequences of the flight response have been investigated in a number of reef fish species, very little work, if any, has focussed on quantifying the energy required to elicit a more extreme defence response, such as that seen in the pufferfishes, even though it is just as likely to be very physiologically demanding. This study will examine the physiological demands of the pufferfish’s antipredator defences and how these may be affected by a warming climate.
 

 

Genevieve Bell - Nucleic acid indices of niche separation in pelagic copeods

Principal supervisor: David McKinnon (AIMS)

The pelagic environment supports a great diversity of planktonic organisms. Copepoda make up the majority of the mesozooplankton, but how so many species of copepods are supported is unclear. Most planktonic copepods belong to the Orders Calanoida or Cyclopoida. Copepods belonging to these two Orders vary in behaviour, with cyclopoids thought to be more metabolically efficient than calanoids. It is hypothesised that differences in metabolic efficiency are an important determinant of the community structure of plankton in the oceans. This study aims to test two hypotheses: (i) that different copepod groups differ in their metabolic requirements; and (ii) that metabolic requirements change with depth

 

 

Yoland Bosiger (2011) Predator-prey dynamics and the effect of daily temporal foraging patterns on coral reef fishes

Co-supervisors: Maud Ferrari (Univ Saskatchewan), Oona Lonnstedt (JCU)

Where is she now? Rolex Scholarship for 2012; Researcher, BBC Wildlife Unit

 

 

Ingrid Cripps (2010) Influence of ocean acidification on predator-prey responses

Principal supervisor: Phil Munday (JCU)

Where is she now? Travelling!

 

 

Miwa Takahashi (2010) Latitudinal influences on the early life history of reef fishes

Principal supervisor: Geoff Jones (JCU)

The influences of temperature on the life history processes of tropical reef fishes in natural conditions are poorly understood. The aim of this in-situ study was to investigate the effects of seasonal and latitudinal temperature gradients on early life history traits of the yellow damselfish, Pomacentrus moluccensis (Family Pomacentridae). Temporal variations in early life history traits were examined over a five-month period during the 2009/2010 reproductive season at Lizard Island, the northern Great Barrier Reef (GBR). Specimens of metamorphosing P. moluccensis were collected using light traps deployed in the vicinity of the reef around the new moon period, when recruitment is highest. A latitudinal comparison was conducted over four locations from northern Papua New Guinea (Kimbe Bay) to the southern GBR across 18° of latitude. This comparison used collections of recently settled juveniles from each location. Both seasonal and latitudinal patterns of larval growth and developmental rates of P. moluccensis were significantly correlated to changes in water temperature regimes.latitudinal comparisons of larval life history traits revealed significant curvilinear models with an optimal temperature slightly above 28ºC at which the highest larval growth, shortest PLDs, and largest settlement size were observed.

Where is she now? Research Officer at JCU

 

Oona Lonnstedt (2009) Effect of body condition and ontogeny on the response of coral reef fishes to chemical alarm signals and their use as secondary predator attractants.

Predation is one of the fundamental processes that impacts on the behaviour, life history and distribution of prey individuals, populations and communities in aquatic ecosystems. A prey’s response to a predator cue is a trade-off between the perceived intensity of current threat and the importance of other activities, such as foraging, mating and maintenance. One way aquatic organisms assess threat is through the use of chemical cues produced by damaged conspecifics, known as chemical alarm cues. This study explored the relative importance of body condition and ontogeny in influencing the production of chemical alarm cues, as well as the response of marine fish to these cues. The study also examined whether damage released chemical alarm cues attract secondary predators that may enhance the survival of prey and also explain the evolution of the chemical alarm cue mechanism.

Where is she now? Undertaking a PhD JCU

 

Alex Vail (2009) Non-lethal influence of predators on juveniles fishes

Non-lethal predator effects include numerous prey behavioural responses. Freshwater fish avoid areas containing active predators, exhibit risk reducing behaviours in the presence of predators, and vary these responses in relation to body condition. Risk assessment plays a key role in the operation of indirect effects of predation. Coral reef fish have well developed sensory systems, with innate recognition of olfactory cues used to make important settlement choices, and the ability to rapidly learn the identity of predators by coupling the olfactory or visual cues of a predator with species specific chemical alarm cues (CAC) and the cues can come from predator faeces.

      The broad objective of this study was to assess the extent to which predators have a non-lethal effect on fish prey at settlement through olfactory and visual cues. Specifically, we examined whether wild-caught settlement-stage reef fishes could innately recognise predator odour. Using y-maze experiments this study tests whether 3 fish species can discriminate among water containing odours from a predator, a non-predator (herbivore), and a control. The study determined whether predator odours affected the spatial patterns of settlement of reef fishes to reef patches. We used replicated field manipulations of olfactory cues to examine the importance of odour from resident predators to the small scale settlement of reef fishes. We also explored whether the diet of the predators (i.e. whether they had been eating fish recruits or not) influenced the reaction of prey to predator odours. We then examined whether settler body condition affects their propensity to avoid predators in the wild. Lastly, choice trials within laboratory mesocosms were used to examine the relative contributions of vision and olfaction to detecting and avoiding predators at settlement.

Where is he now? Undertaking PhD Univ Cambridge, UK 

Cal Mero (2009) The effects of behavioural syndromes on the survival and growth of newly settled damselfishes

When behaviours such as aggression and boldness are correlated across situations and contexts they are referred to as a behavioural syndrome. Behavioural syndromes contribute towards an individual’s survival or demise by influencing the behaviour that they may demonstrate under a range of conditions, such as in the presence or absence of predators. Of particular importance is the study of the consistency of these behavioural syndromes and to what extent, they remain unchanged across contexts and situations. The extent to which prey will take risks will be influenced by a number of factors (e.g. hunger, previous growth history or body condition, metabolic state) that change on a number of different temporal scales. The broad objective of this project was to determine the behavioural syndromes for a number of species of newly settled damselfish, and determine how consistent these behavioural syndromes were over time. Specifically, this study addressed 2 specific aims: determine the consistency of behavioural syndromes in newly settled damselfish, Pomacentrus amboinensis and P. sp A over a 5d period; establish the behavioural syndromes of a population of newly settled damselfish and their link to survival.

 

 

David Jones (2008) The genetic population structure of a coral reef fish, Pomacentrus amboinensis, across the Great Barrier Reef and Papua New Guinea
Co-supervisors: Line Bay, Dean Jerry

This research explored the extent of connectivity among populations of the damselfish Pomacentrus amboinensis on reefs of the Great Barrier Reef by examining the spatial and temporal patterns in genetic structure of the populations. This broad objective was divided into four specific aims: To develop microsatellite loci for use in population genetic studies for P. amboinensis; examine the spatial population genetic structure of P. amboinensis both over large (400 – 1200 km) and small (5 – 20 km) spatial scales; investigate temporal patterns in the population genetic structure of P. amboinensis by comparing populations from Lizard Island one generation apart; examine temporal genetic structure among recruits within one lunar replenishment pulse.

Where is he now? Undertaking a PhD at JCU


James Moore (2007)  The influence of coral bleaching on early life-history processes of coral reef fishes
Co-supervisor: Phil Munday

Global warming is expected to cause significant degradation to reef communities as a result of increased coral-bleaching at higher sea temperatures. How settlement patterns and early life-history performance of coral reef fishes are affected by coral bleaching is largely unknown. . In this study, we used a combination of laboratory and field-based experiments to test the behavioural responses of settling fish larvae to bleached coral and to assess the impacts of coral bleaching on settlement patterns and post-settlement growth and condition of coral reef fishes.

Where is he now? Marine Science Program, Science Division, Department of Environment and Conservation, Western Australia

  

Jessica Maddams (2007) Influence of parental effects on production and larval quality of a serial spawning reef fish

An individual’s fitness is defined as the total number of offspring produced over its reproductive lifetime that survive to reach their own successful reproduction. It has long been recognised that variability in offspring can result from non-genetic parental effects. The way a mother invests energy into reproduction may influence the developmental schedules, growth and performance of her offspring, and inevitably the numbers that survive to contribute to the next generation. Maternal investment to reproduction may change in response to her size, age or body condition, and also may be influenced by the environmental conditions she experiences. Ultimately her reproductive fitness results from a balance between the cost to herself and the gain to her offspring. For many organisms the trade-offs associated with reproduction are complicated by spawning multiple times within a breeding season (i.e., serial spawning). Many tropical reef fishes serially spawn, producing multiple egg clutches over a breeding season that may last many months.

        The broad aim of the present research was to investigate the influence of parental effects on the production and quality of the resulting offspring of a benthic spawning damselfish, Pomacentrus amboinensis (family: Pomacentridae). Specifically this project had three aims: 1) To determine the influence of parental characteristics on egg production and embryo survival. 2) To investigate the influence of parental characteristic on offspring characteristics. 3) To explore if egg production and larval characteristics were affected by sequential spawning.

Where is she now? Research Officer JCU

 

Jennifer Donelson (2006) Parental and environmental influences on the early life history of a reef fish
Co-supervisor: Philip Munday

The broad aim of my project was to investigate parental and environmental effects, and the interaction between these factors, on the life history of a reef fish. The species chosen for this study was Acanthochromis polyacanthus. Importantly this species does not have a pelagic larval stage as seen in other reef fishes. Consequently it is possible to examine the effects of parental feeding history from the day of hatching. Specifically this project had three aims: 1) to test for parental effects on offspring life histories, 2) to examine the effect of current offspring environment on life history traits and 3) to test for interactions between parental and environmental effects on the life history of a reef fish.

Where is she now? Postdoc with University of Technology Sydney with Prof Dave Booth.

 

Rachel Manassa (2004) The use of chemical alarm cues for predation risk assessment in coral reef fishes

The presence of predators in aquatic systems has been shown to influence the behaviour of prey, with individuals who are capable of early detection and evasion likely to show an increase in overall survival. Olfactory cues that indicate the activity or presence of a predator have been found to be commonly used among freshwater fishes, and have been shown to be important in the assessment of predation risk. The importance of olfactory mechanisms of predator detection is largely unknown for marine species. This study explored the use of chemical alarm cues by marine fishes in order to assess predation risk. A series of manipulative experiments were conducted to establish whether risk assessment mechanisms, which are known to occur in freshwater fishes, are prevalent in marine species. Three ecologically critical concepts of chemosensory predator assessment were examined: (i) the use of chemical and visual cues, (ii) predator dietary cues and (iii) social transmission.

Where is she now? Post-doc,

 

Tom Holmes (2004) - Selectivity of mortality on newly settled reef fishes

This study is explored the selectivity of predation on tropical reef fishes over the period during and immediately after settlement.  Using settlement stage Pomacentrus amboinensis (Pomacentridae) as a model prey species, the selectivity of the multi-species predator pool was examined for a variety of different prey characteristics over a number of different study sites.  Specifically, prey standard length, condition and previous predatory experience was manipulated during paired choice trials to gain a better understanding of the processes underlying predator selection.  To explore the question the predators perspective, the size selective mechanics of an individual predatory species (Synodus variegatus) was examined over a range of predator sizes. 

 

Jenny Pickering (2004)  The role of parasites in early life history stages of coral reef fish from Lizard Island, Great Barrier Reef
Principal supervisor: Lexa Grutter (University of Queensland)

Three aspects of the ecological role of parasites in the early life history stages of coral reef fish from Lizard Island, Great Barrier Reef, Australia were investigated.  Firstly, two cohorts of larval, recently settled and juvenile stages of the coral reef fish Pomacentrus moluccensis (Pomacentridae) were examined for parasites. Parasite prevalence was 0 and 4% for larval stage fish, 34 and 56 % for recently settled fish and 42 and 49% for juveniles. Secondly, the sizes and growth rates of parasitised and unparasitised juvenile stage P. moluccensis were compared. Finally, the susceptibility to gnathiid isopod infection and their effect on larval and recently settled stages of a species with a pelagic larval phase (Neopomacentrus azysron -Pomacentridae) and the juvenile stage of a species with no pelagic larval phase (Acanthochromis polyacanthus -Pomacentridae) was compared. This study has important implications for understanding the role of parasites in the evolution of the pelagic larval stage of coral reef fish.


Lisa Peacock (2004) Predators target rare prey in coral reef fish assemblages
Co-supervisors: Glenn Almany, Geoff Jones

 Predation can result in differing patterns of local prey diversity depending on whether predators are selective and, if so, how they select prey. A recent study comparing the diversity of juvenile fish assemblages among coral reefs with and without predators concluded that decreased prey diversity in the presence of predators was most likely caused by predators actively selecting rare prey species. We used several related laboratory experiments to explore this hypothesis by testing:(1) whether predators prefer particular prey species, (2) whether individual predators consistently select the same prey species, (3) whether predators target rare prey, and whether rare prey are more vulnerable to predation because they differ in appearance or colouration compared to common prey.

 

Johan Larson (2004) The use of chemical alarm signals in tropical coral reef fishes

This study focuses on the use of chemical alarm signals in tropical coral reef fishes. In as series of appropriately controlled laboratory experiments I investigated whether two members of the family Pomacentridae, Pomacentrus moluccensis and P. amboinensis, responded with an alarm response to chemical cues from the skin of injured conspecifics. To investigate the importance of chemical alarm signals to fishes under natural conditions the response of the goby, Asteropteryx semipunctatus, to conspecific skin extracts in the field was compared to its response in the laboratory. The effect of hunger on the production of, and response to, chemical alarm signals in A. semipunctatus was investigated in a food manipulation experiment. Lastly, the role chemical alarm signals play in facilitating learned recognition of novel chemical cues was investigated under laboratory conditions.

 

Masters

 

Donny Warren- Effects of developmental thermal acclimation on competition in two coral reef damselfish

Global warming is an imminent threat to Earth’s ecosystems and will have a large impact on community structure. As surface temperatures rise, species will be forced to adapt to a warmer climate to maintain competition for resources. However, not all species possess equal ability for thermal acclimation. By studying capacity for thermal acclimation and how it affects competition, we can gain understanding of what the future community structure may be. Here I propose a behavioural study using two resource competitors, the damselfish Pomacentrus amboinensis and P. moluccensis, raised in a range of elevated temperatures to determine whether developmental thermal acclimation affects competition for shelter resource.


  

Iris Krehahn - Influence of topography on predator-prey dynamics

The structure of habitats constantly changes over a range of temporal scales and disturbance often leads to chnages to the structure of habitats. Topography affects how prey percieve their predators and predators detect and capture their prey. This project examines how topographic complexity on coral reefs affects the dynamics of predator-prey interactions.


Travis Shute - The ecology of three predators from Kimbe Bay, PNG

Co-supervised with Geoff Jones

Cecilia Villacorta Rath (2011) Selective mortality of larval and juvenile Spratelloides delicatulus in Northern Great Barrier Reef
Co-supervisor: Mark Meekan (Australian Institute of Marine Science)

Spatelloides delicatulus is a fast growing tropical species and is the most common of the three species of sprats found in northern GBR waters. S. delicatulus is one of the main species of baitfish of the Solomon Islands used in the tuna fishing industry. Knowledge of the factors affecting its distribution and abundance is fundamental to management of the resource. The species have otoliths which can be used as a historical record of individual growth and developmental stress as increments in the otoliths are deposited daily. Their fast growth and common occurrence makes them an ideal species with which to explore the link between environmental conditions, growth and mortality. The aim of this study was to determine whether mortality of Spratelloides delicatulus larvae was selective for growth-related traits and explore the mechanisms underlying selective mortality through a longitudinal study of single and multiple cohorts over two consecutive years.


Where is she now? PhD, University of Tasmainia

 

 Jaclyn Davies (2010) - Influence of topography on use of sensory modes in risk assessment

Coral reefs are patchy with respect to all aspects of biological and physical organization. These high diversity ecosystems vary greatly in topographically complexity or architecture and also in important biological determinants, such as food availability. Evidence suggests that both architecture and food availability are likely to influence the way an organism assesses predation risk. The ease at which sensory cues are dispersed through an environment will influence the balance of senses used to assess predation threat. Organisms with a poor feeding history take should take more risks than those in high body condition. It is also expected that in areas of high architecture, organism will place more weight on olfactory information than visual information. While predictions can be made from previous studies the interactive effects of habitat architecture and feeding history are unknown. This study uses laboratory studies to test these predictions.
 
 

 Will Feeney (2010) Mesopredator impacts of coral reef fishes

Nicola Willson (2010) - Efficacy of Bioelectrical Impedance Analysis for estimating the body condition of marine fishes

An individual’s capacity to cope with fluctuations in their environment is dependent on their physiological condition, with fish in better condition more able to withstand these changes. Assessing body condition can allow the prediction of how populations will response to future changes in their environment. Bioelectrical impedance analysis (BIA) is a fast, non-destructive method of measuring physiological condition compared to commonly used existing methods. This project examined whether BIA measurements could accurately predict the physiological condition of the small damselfish, Acanthachromis polyacanthus. Resistance and reactance was significantly different between fish in different physiological conditions. Prediction of physiological condition using BIA regression with morphometric and hepatic variables was dependent on gender and size. Electrode placement had a significant effect on resistance and reactance. BIA appears to be a more successful tool for measuring physiological condition in larger fish with a cylindrical compared to laterally compressed shape as electrodes are placed far enough apart to reduce interference and there is more tissue to provide resistance and reactance. Future studies should focus on the advancing the application of BIA as a fast, effective and non-destructive method of measuring physiological condition in the fields of aquaculture and ecology.

 

 

Poh Leem Choo (2010) - Ontogeny of burst performance

Where is she now? Marine Biologist, WWF-Malaysia

 

Crystal Neligh (2009) Link between performance and metabolism and the importance of temperature



Christine Weaver (2009) Competition between two species of newly settled damselfish: implications for local distribution patterns

Competition is one of the most fundamental processes structuring reef fish communities, but little is known of the role of competition in influencing spatial patterns and survival around the time of settlement from the larval phase. This study examined the impact of competitive behavioural interactions between two species of newly metamorphosed damselfish that overlap in habitat usage.


Kim Lema (2008) Lipofuscin as an indicator of developmental age in coral reef fishes
Co-supervisor: Monica Gagliano (University of Western Australia)

Lipofuscin has long been known as the ‘age pigment’ and referred to as a universal index of physiological senescence. As this pigment is related to metabolic activity, it could be of interest to use it as a temperature stress marker in reef organisms in the light of the predicted increases in global temperature. Most studies on this marker on marine organisms have been done in crustaceans. Before the technique can be applied it is necessary to determine an efficient way of accurately quantifying the amount of lipofuscin, which is stored as small granules in the brain tissue. This study compared 4 techniques to quantify the occurrence of lipofuscin in brain tissue: confocal microscope and 3 histochemically stains (Sudan Black, Schmorls and PAS). The results show that Sudan Black was the most effective way of quantifying lipofuscin, whilst confocal microscopy lead to an overestimation of the amount of lipofuscin present due to high numbers of autofluorescent bodies. Sampling throughout the brain found that lipofuscin was concentrated in the optic tectum of the mesencephalon. This study sets the foundation for the wider use of the technique to address the impacts of natural and anthropogenic stressors of senescence.

Chris Ryen (2008) Sex-specific growth dynamics in protogynous hermaphrodites
Co-supervisor: Philip Munday

Sexual size dimorphism is a characteristic of many animal species but the ways in which size differences between males and females originate in sex changing species is little understood. The study investigated growth mechanisms underlying sexual size dimorphism in protogynous hermaphrodites, using tropical wrasses as a focal study group. The aims were to: 1) identify a relationship between the strength of the social organization within a group and the timing of growth divergence between sex changing and non sex-changing individuals; and 2) to identify changes in behaviour and space use associated with sex change within a group. It was predicted that where individuals were under strict social control, sexual size dimorphism would come about by a growth spurt associated with sex change. It was also predicted that in more loosely controlled social groups, prior growth history would play a greater role in the development of sexual size dimorphism. The strength of social systems for four species of wrasse (family: Labridae) was quantified by behavioural observations and compared to growth trajectories of sex-changing and non-sex-changing females. The wrasse species used in this study were: Coris batuensis, Stethojulis strigiventer, Halichoeres miniatus, and Cirrhilabrus exquisitus. Comparisons were made of social systems and growth patterns both across species and within a species to determine if social influences on growth were species specific or specific to the social system.


Alison Sampey (2007) Distributions and diets of the larvae of tropical shorefishes near the Northwest Cape of Australia
Co-supervisor: Mark Meekan (Australian Institute of Marine Science)

The importance of understanding the factors influencing growth and survival of larval fishes and their effect on subsequent recruitment has been recognised in temperate areas since the late 1800’s. Despite this, our knowledge of these topics is severely limited for tropical larval fishes. In this study the spatial and temporal abundance patterns of larvae were described from towed bongo plankton nets at sites on the southern North West Shelf of Australia (NWS) (21º49'S, 114º14'E), between October and February of 1997/98 and 1998/99. The first summer was characterised by El Niño - Southern Oscillation (ENSO) driven upwelling and high primary productivity, compared to the second summer when water temperatures were warmer and primary production was lower. Over the course of the study 76 families were captured with the bongo nets. The diets of 591 individuals from 50 families of tropical larval shorefishes collected off the Northwest Shelf of Australia (21º49'S, 114º14'E) were also described, effectively doubling the number of families for which have we dietary information.


Katherine Munkres (2005) Development of polymorphic microsatellite markers for the yellow damselfish, Pomacentrus amboinensis
Co-supervisor: Dean Jerry

Coral reef fishes display a wide variety of mating systems, however, little is known about the reproductive strategies of most species.  This study isolated and characterized six highly polymorphic microsatellite markers to be used in describing the mating system of the social coral reef fish Pomacentrus amboinensis (Pomacentridae).  Of the microsatellite markers developed to date, 50% are dinucleotide repeats, 16.7% are trinucleotide repeats, and 33.3% are tetranucleotide repeats.  The high proportions of tri and tetra repeats will be useful in reducing confounding factors such as null alleles, electromorph pairs, and the presence of stutter bands; which could result in the misidentification of parents and an under or overestimation of the number of parents contributing to a single brood.  Ultimately, this project will explore the social and ecological factors controlling reproductive success in P. amboinensis.  The results of this study will contribute to our understanding of the evolution of mating systems and may provide information about the effective population size of current day populations.


Katherine Dunn (2004) Bioluminescent behaviour of the Flashlight Fish, Photoblepharon palpebratus

Bioluminescence is a widespread phenomenon in the marine environment although its function remains largely speculative. This study represented the most detailed study to date on the role of the light organ and associated membrane in the Anomalopidae. The blinking behaviour of the flashlight fish, Photoblepharon palpebratus (Anomalopidae), was examined to determine the extent of circadian rhythmicity. Manipulations of food availability were used to explore the influence of food availability and activity on blinking rate. Results were marked by a high degree of variation between individuals, suggesting diel rhythms and prey availability are not strong selective pressures for blinking rates in this species. While low blinking rates were associated with a wide range of activity levels, increases in blinking rates above 20 blinks per minute were associated with increased activity levels. These results suggest blinking is used primarily for defence, and that the rate is highly individualistic.

Where is she now? Working for as a Director/Producer at Digital Dimensions, Cairns




Jennifer Drost (2004) Within-reef variation in energy allocation and life history traits of Pomacentrus amboinensis at Lizard Island, Great Barrier Reef

Variation in life history traits and energy allocation strategies among organisms has become a central focus of ecological research.  As organisms proceed through their life cycle, they harvest energy from the environment and invest it in various life functions including growth, reproduction, and storage.  In the challenge of allocating energy to these demands, organisms must not only consider the costs and benefits of each function, but also the state of their local environment.  There is great potential to use coral reef fish as models to explore life history theories and energy allocation strategies as they are characterised by a dispersive larval stage that is liberated into a variable environment and a relatively site attached benthic stage as adults.  This study examined the effect of location and associated environmental factors on the allocation of energy to different life history traits of Pomacentrus amboinensis (family Pomacentridae) on a mid-shelf reef at Lizard Island, Great Barrier Reef.  Body traits describing storage, reproduction, and growth were measured from fish that were collected from 3 locations (Bommie Point at the oblique side of the reef, Watson’s Reef at the backside of the reef, and the Lagoon). Results indicate populations of P. amboinensis at Lizard Island experience trade-offs in channeling available energy between storage, reproduction, and growth.  Populations demonstrated different energy allocation strategies across sexes and reefs at Lizard Island.  Generally, females allocated most of their energy into reproduction and storage, while males and juveniles allocated their energy towards growth. Fish located at the leeward location displayed higher reproductive potentials and were in greater physiological condition at a cost of lower mean asymptotic sizes and delayed maturity.   Fish at the reef front were in greater physiological condition with higher mean asymptotic sizes at a cost of delayed maturity and lower reproductive potential.  Fish from the lagoon displayed higher growth rates and early maturity at a cost of lower physiological condition and lower reproductive potential.  These variations in energy allocation strategies were suggested to be a result of environmental factors such as food availability, food quality, fish density, predation, competition, and/or temperature.


PhD

 

James White - The role of boldness in the ecology of juvenile marine fishes
Co-supervisor: Mark Meekan (AIMS), Maud Ferrari (Univ Saskatchewan).

Recent studies have noted consistent, individual differences in the behavior of many species of organisms. Individuals may differ in behavioral traits such as boldness, aggressiveness, activity levels, reactivity, sociability, fearfulness and exploration and these consistent signatures of behaviour are often termed personalities or behavioral syndromes. Variation and flexibility in these traits has important implications in understanding the ecology and evolution of various species. In particular, consistent behaviors are important to population ecology through limiting distribution and abundance, affecting species interactions, population dynamics, ecological invasions and responses to environmental and ecological shifts. This research explores various aspects of the extent to which coral reef fish demonstrate personalities and the importance of these to their fitness.

Where is he now? Teaching at a school in Texas

http://www.jamesryanwhite.com/

 

Bridie Allan - Predator-prey interactions under a CO2 rich environment

Co-supervisors: Phil Munday (JCU) & Paolo Domenici (Istituto per l'Ambiente Marino Costerier, Italy)

Predation is one of the key processes structuring communities in ecological and evolutionary time. Despite the ecological and evolutionary importance of predation, it is one of the most poorly understood processes in one of our world’s most biologically diverse and threatened ecosystems, coral reefs. Assessing how predator-prey interactions will change in future marine environments is vitally important. The proposed study investigates an area of research that is yet to be explored: the kinematic analysis of predator-prey interactions under future climatic scenarios. By creating future marine environments, it allows us to predict how ecosystem dynamics and communities may respond to climate change.

Where is she now? Research Officer at JCU and applying for post-docs

Bridie Allan
 

 

 

Justin Rizzari - Trophic impact of large predators on coral reefs and management implications

Co-supervisor: Ashley Frisch (ARC Centre of Excellence)

The aim of this research is to investigate the importance of indirect effects of predation on the trophic ecology of coral reef ecosystems across a range of key functional groups. The observed patterns will be related to not only evolutionary and community responses, but also to reef resilience and implications for management.
 
Where is he now? Research Officer at JCU and applying for post-docs
 

 

Ian McLeod - Effects of ocean warming on the connectivity of coral reef fish populations

Co-supervisors: Geoff Jones (JCU), Phil Munday (JCU)

This research focuses on the impacts of sea surface temperatures on the early life history stages of coral reef fish and the consequences of these impacts on the connectivity of coral reef fish populations. Specifically it addresses: What are the relationships between natural temperature gradients (spatial and temporal) and the early life history traits of coral reef fishes? What are the effects of ocean warming on the early growth, survival and body condition of juvenile reef fish at equatorial regions, where they may already be living at or beyond their thermal optima?  What are the interacting impacts of temperature and variable food supply on the performance of fish larvae? Click for CV
 

Where is he now? Post-doc at TropWater JCU


 
 

 


Alexandra Carter - The effects of no-take zoning, region and year on reproductive output of the common coral trout, Plectropomus leopardus
Principal supervisor: Garry Russ (JCU), Andrew Tobin (JCU)

The primary extractive use within the Great Barrier Reef Marine Park is fishing and the common coral trout Plectropomus leopardus, a batch spawning protogynous hermaphrodite, is the major recreational and commercial target species. Fishing has been implicated in reducing the size and age at sex change of P. leopardus, and significantly higher densities and older and larger females have been reported on reefs closed to fishing. The overall objective of this study is to examine the effects of no-take zoning, region and year on reproductive output of the common coral trout, Plectropomus leopardus. The specific aims are to: determine the length-fecundity and age-fecundity relationships for P. leopardus on the GBR; determine whether P. leopardus length-fecundity and age-fecundity relationships vary between regions, years, and reefs zoned open and closed to line fishing on the GBR; determine whether P. leopardus egg production per unit area varies between regions, years, and reefs zoned open and closed to line fishing on the GBR; examine the relationship between egg and larval quality and maternal length and age for P. leopardus.

   

Rachel Manassa - Social learning and its role in threat assessment by reef fishes
Co-supervisor: Maud Ferrari and Doug Chivers (University of Saskatchewan)

Rachel Manassa

Where is she now? Post-doc, Sydney

 

 

Gabrielle Miller- Influence of acidification on early development in coral reef fishes
Principal supervisor: Phil Munday

Gabrielle Miller

Where is she now? Humbolt Fellowship, Germany

 

 

Matthew Mitchell- Antipredator defence through chemical alarm cues - how common amongst tropical marine fishes?
Co-supervisor: Maud Ferrari (Univ. Saskatchewan)


Chemical alarm cues have been found to be used for risk assessment in many aquatic organisms. The present study aims to explore the importance of chemical alarm cues for marine fishes, by examining the mechanism in a diversity of species across a range of marine families. The extent to which fishes respond to cues from heterospecifics that differ in phylogenetic distance will also be examined, and the importance of this mechanism in learning novel predators will be ascertained.

Where is he now? Post-doc, University of Saskatchewan

Matthew Mitchell

 

 

Amelia Wenger - Effect of suspended sediment on early life stages of planktivorous damselfish
Principal supervisor: Geoff Jones (JCU)

Sedimentation is considered to be one of the major stressors to coral reef ecosystems and yet, very little is known about the ecological implications of increasing amounts of sediment on reefs. Many fish species depend on corals for food and habitat and thus can be indirectly impacted by sediment due to habitat degradation. In addition, reef fish may be directly impacted by sediment, particularly suspended sediments.  This is expected to be a particular problem for planktivorous fishes where the ability to visually locate prey in the water column may be impaired.  The overall aim of this project is to expand our understanding of how sedimentation influences the ecology and life history of planktivorous fishes on the Great Barrier Reef and threshold levels of suspended sediment at which effects may be seen.  The specific questions addressed will be as follows:  (1) Does sedimentation affect the settlement success of larval fish?  (2) How does increasing sedimentation affect the physiological condition of individuals?  (3) What are the threshold levels of suspended sediments that have an impact on fish foraging success and condition?

Amelia Wenger
 

 

Jenni Donelson (2012) Climate change and the future for coral reef fishes: impacts and adaptation
Principal supervisor: Phil Munday; Co-supervisor: Roland Pitcher (CSIRO)

Changes to the ocean’s temperature is likely to have significant effects on the reproductive capacity of fishes and the growth and survival of their offspring, with potentially serious consequences for the sustainability of fish populations. Ultimately, however, it is the potential for species to acclimate and adapt to climate change that will set the boundaries for future population characteristics. Jenni will investigate the effects of sea water temperature on a common coral reef fish, over temperature ranges likely to be experienced by natural populations over the next 50-100 years. Replicate lineages will be reared through successive generations at each of the three focal temperatures (current, +1.5oC and +3.0oC) and the reproductive performance of adults and life history attributes of the offspring will be tested at current-day and elevated temperatures in each generation. Some reef fishes appear to have considerable potential for short-term acclimation to increased ocean temperature, but whether this will affect the fitness of their offspring and how quickly favourable traits will be transferred between generations is currently unknown.

Where is she now? Post-doc at University of Technology, Sydney

 

Tom Holmes (2010)- Selectivity of predation on newly settled tropical reef fish

We currently know very little about predation on tropical reef fishes. What we do know is largely limited to predator identity and their dynamics on adult fishes (eg. coral trout). Knowledge of the trophic links between predatory fishes and their prey is crucial for the management of fisheries and conservation of tropical marine ecosystems. It is only by understanding predator-prey dynamics that we can predict how prey may respond to changing predator populations or vice-versa. This project addresses the interaction between prey and predatory coral reef fishes immediately during and after settlement, when mortality can be upwards of 60% within the first 2 days. If this high mortality is selective then it will have a major impact on the distribution of body attributes and life history traits in the population.

        The present study aims to determine the extent to which mortality at this early life stage is selective and the mechanisms underlying selection. Specifically, this study aimed to determine: (1) whether predators are selective with respect to prey phenotype or performance, (2) how predator size and identity influence prey size selection, (3) how relative prey frequencies influence predator size-selection, (4) whether prey body size is more important than previous experience in determining the outcome of a predator-prey encounter, and (5) the importance of chemical alarm cues released by prey in mediating predator-prey dynamics.

Where is he now?
Marine Researcher, Marine Science Program, Science Division, Department of Environment and Conservation, Western Australia

 

Matt Fraser (2010) Egg predation at fish spawning sites: trade-offs for fitness

The broad goal of this research initiative was to examine the importance of egg feeding at fish spawning aggregation sites for the population dynamics of fish that are able to exploit the resource. The research follows the interaction from the dynamics of the planktivores aggregating to feed on the spawn, through to its influence on the performance characteristics of the larvae they themselves spawn. Specifically, the research addressed 4 aims: determine the link between the temporal pattern of spawning aggregation, and spatial patterns of planktivores that feed on spawn; examine the importance of foraging on gametes at spawning aggregation sites to the energy budget of selected planktivorous fishes; explore the influence of feeding on spawn to the demography and physiological condition of selected planktivores; investigate whether feeding on spawn influence reproductive output and the quality of larvae produced.

Where is he now? with 6mo of finishing became Project Marine Scientist at URS Asia Pacific, Perth; presently at National Offshore Petroleum Safety and Environmental Management Authority (NOPSEMA), Perth



Stefan Walker  (2010) Phenotypic plasticity across natural- and sexual-selection gradients in a reef fish  Co-supervisor: Phil Munday

 Theory suggests that the social conditions into which an individual settles can have profound influence over which set of life history strategies are best suited for maximising expected lifetime fecundity. Consistent, but unpredictable variation in social system type within species is therefore hypothesised to be a major driver of the evolution of individual trait plasticity mechanisms. This is because those individuals that can optimise life history strategy in response to current social-based selection pressures will have an advantage over those individuals that cannot.
       In reef fishes, selection for individual trait plasticity mechanisms in response to social-based selection pressures should be particularly strong. This is because most reef fish life histories include a dispersive pelagic larval phase, such that individuals frequently settle to a social environment that is very different from the natal state. However, our understanding on the extent of individual trait plasticity in fishes, and the adaptive significance of particular traits within particular society types, is extremely limited. This paucity of information hinders our ability to conceptualise evolutionary theories pertaining to the origins and maintenance of trait-, sex- and species-diversity, and our ability to successfully manage and conserve fish populations and communities.   
      My thesis examined the ecological and evolutionary significance of individual trait plasticity in response to social factors using the polygynous sex-changing sand perch Parapercis cylindrica (family Pinguipedidae) as the model. Using a combination of theoretical, comparative and experimental procedures I tested the general hypotheses that: 1) social factors have played a significant role in the evolution of individual trait plasticity, and that; 2) this plasticity manifests fundamental relationships between social system type, individual phenotypic expression, and the functioning and productivity of particular social groups.

Where is he now? Lecturer with JCU Singapore; then a post-doc with the ARC Centre of Excellence for Coral Reef Studies


Monica Gagliano  (2007)- The role of early life history traits on the survival of a coral reef fish

Selective mortality within a population, based on the phenotype of individuals, is the foundation of the theory of natural selection. Even small phenotypic differences among individuals early in ontogeny can strongly affect survival and performance later in life. Consequently, variation in early life history traits can have important repercussions on population structure and dynamics. Yet, the role of phenotypic variation throughout the ontogeny of tropical marine fishes remains largely unexplored. This study examined the extent to which environmental and parental effects generate variation in the early life history of a tropical marine fish (Pomacentrus amboinensis) and the consequences of such variation for survival in the wild.

Where is she now? Post-doctoral fellow, AIMS@JCU Towsville; now a post-doc with University of Western Australia




Maya Srinivasan Recruitment in time and space: the dynamics and distributions of reef fish populations on a low latitude coral reef

Co-supervisors: Howard Choat (JCU), Julia Caley (AIMS)


Despite the fundamental importance of replenishment to marine organisms, very few studies have examined recruitment patterns, habitat degradation and the consequences for reef populations at low latitudes. This study employed both descriptive and experimental approaches to provide the foundation and build an understanding of patterns, causes and consequences of reef fish recruitment in Kimbe Bay.  Common generalizations regarding the determinants of patterns in recruitment and their effects on the distribution and abundance of adults were examined from a multi-species and multi-family perspective.  Primary attention was given to similarities and differences between damselfishes (Pomacentridae) and wrasses (Labridae), because of their numerical dominance among fishes recruiting to coral reef habitat. The specific objectives were to examine: (1) Temporal patterns in recruitment, with a particular emphasis on extended recruitment periods and long-term patterns in the magnitude of recruitment; (2) Spatial patterns in recruitment, with particular emphasis on microhabitat specialization and the role of microhabitat availability in determining reef-wide patterns in recruitment; (3) The underlying mechanisms responsible for establishing and reinforcing distinct narrow depth distributions in the recruitment of reef fishes in this region; and (4) The influence of recruitment patterns on the temporal dynamics and spatial distributions of adult fish populations against a background of declining reef health. 

Where is she now? Assistant lecture, School of Marine and Tropical Biology, James Cook University.



Ashley Frisch Population biology and fishery ecology of the painted crayfish,  Panulirus versicolor, on the Great Barrier Reef


Panulirus versicolor, otherwise known as the painted crayfish, is a palinurid (spiny lobster) that inhabits coral reefs of the Indo-Pacific region, including Australia’s Great Barrier Reef (GBR) where it forms an esteemed component of the local recreational spearfishery.  At present, management strategies for P. versicolor are based solely on precautionary principles, since prior to this study virtually nothing was known about this species.  The broad goal of this thesis was therefore to describe the population biology and fishery ecology of P. versicolor on the GBR, thereby providing a framework for the development of a comprehensive management scheme for this important fishery resource.

Where is he now? Fisheries Manager, Great Barrier Reef Marine Park Authority; now post-doc with the ARC Centre of Excellence for Coral Reef Studies.

David Feary (2006)- Consequences of coral disturbance for fish community composition
Co-supervisor: Geoff Jones

Although a large body of theory exists on the processes that influence th
e dynamics of coral reef fish communities, little is known about the processes that underlie changes in fish communities due to coral degradation. This study explored the repercussions of live coral degradation on the demographic mechanisms structuring tropical reef fish communities. Specifically, it examined 4 issues:1) The role of coral degradation in influencing the structure of coral associated reef fish communities; 2) The influence of coral degradation in structuring recruitment patterns for a range of common Indo Pacific reef fishes; 3) The role of habitat dependency in influencing species emigration ability between degraded and live coral colonies; 4) The physiological response of coral associated reef fishes to low live coral.

Where is he now? Postdoctoral Researcher, United Nations University-INWEH, Dubai; now a post-doc with Univ Western Sydney.

 

John Claydon (2005) The structure and dynamics of spawning aggregations of coral reef fish
Co-supervisor: Geoff Jones

Many tropical fish species aggregate to spawn at particular locations. These have historically been targets of fishing pressure, but are in recent years are increasingly become the focus of conservation efforts as sites for no-take reserves. Little is understood of the biology or ecology of the fishes that aggregate at these sites and the importance of these sites for reproduction. he overall goal of this study was to evaluate the structure and dynamics of spawning aggregations and develop a cost-benefit approach to explain their occurrence and distribution. Specifically, the study: identified which species formed spawning aggregations and where and when they were formed; determined whether spawning aggregation sites can be characterised with regard to physical and biotic parameters; determine whether the location and timing of aggregative spawning is influenced by currents; explored the migration patterns of aggregative spawners.

Where is he now? Director, Center for Marine Resource Studies, South Caicos, Turks & Caicos Islands, British West Indies



Bridget Green (2004) Parental and environmental effects on the early life history of a tropical reef fish, Amphiprion melanopus


Tropical coral reef fish larvae are characterised by high mortality, which is predominantly driven by size- and growth- selective processes. While recent studies of environmental correlates have explained 7 - 36 % of the variation in larval growth rate in wild populations, the majority of the variation in growth rate and recruitment remains unexplained. This study used a series of laboratory experiments to assess the contribution of environmental and parental influences on embryonic, larval and juvenile growth and development in a tropical marine fish species, Amphiprion melanopus (Pomacentridae). Specifically the study addresses the following 3 aims: 1) To determine the importance of the embryonic period to development and condition at hatching we investigated: the structural and physiological changes an embryo undergoes through development in relation to changing oxygen requirements; the relative variation in size and physiological measures such as oxygen consumption amongst embryos within a clutch; 2) To describe relative roles of male and female parents in nest tending in response to minor environmental variation, summarising the parental contribution to their offspring through nest tending behaviour; 3) To investigate how parental and environmental influences interact and affect embryo and larval and juvenile condition by differentiating between paternal, maternal and environmental contributions to larval condition and performance.

Where is she now? Research Scientist, Crustaceans Section, Tasmanian Aquaculture and Fisheries Institute, Hobart, Tasmania

Web by onLine247