Animal Behaviour topics

Country codes: HO (Honduras), IN (Indonesia), MA (Madagascar), ME (Mexico), PE (Peru), SA (South Africa)

HO09 Angrier in the middle? Does territorial aggression differ with elevation and competitors in tropical understorey passerines?

Range patterns of species on tropical mountains are generally typified by narrow elevational distributions, particularly in birds, but little consensus as to the exact causes of these distributions has been reached. Physiological stress, ecotones (e.g. habitat and temperature) and aggression between related species may restrict these distributions, but it remains unknown as to whether birds are subject to greater territorial pressures within or at the edges of these elevational ranges as a result. Several species that are suitably abundant and of which the elevational ranges are sufficiently understood, offering ideal subjects for which to study aspects of territoriality, are present in Cusuco National Park, Honduras (e.g. black-headed nightingale-thrush, Catharus mexicanus, and grey-breasted wood wren, Henicorhina leucophrys). A range of projects are possible using playback experiments to assess differences in intraspecific aggression with elevation and local climate regimes and whether interspecific differences occur in range overlaps. This project will complement work currently being undertaken on the role of physiology and aggression in defining the elevational distributions of tropical cloud forest species, focusing on Catharus nightingale thrushes.

Extended Project Summary

HO13 Ecology and behaviour of bats in tropical cloud forests, Honduras

Cusuco National Park has a fantastic diversity of bats that have adapted to the incredibly complex landscape with huge variation in elevation, temperature and rainfall resulting in a wide range of habitats. Bats in the park have been monitored between June and August each year since 2006 using mist net surveys. Over 50 species of bats have been captured at Cusuco including insectivores, nectarivores, frugivores, carnivores and sanguivores. In addition to abiotic data on lunar phase, precipitation and temperature, habitat measurements are also available. Potential ecology projects include examining the effects of abiotic variables, prey abundance and/or habitat type on bat abundance or demography. Studies could also examine how ecological variables contribute to annual variation in bat abundance or diversity using Opwall’s historical data. The abundance and diversity of bats in Cusuco permits comparisons within or across species or guilds. In addition to mist netting, acoustic surveys using ultrasonic recording equipment are now being implemented. This permits projects on vocal behaviour, such as examining echolocation or social vocalisations in individual species, developing species identification using echolocation signals, or comparing mist net and acoustic survey data for species presence and abundance.

Extended Project Summary

HO17 The dynamics of mutualistic cleaning interactions on Caribbean coral reefs

On coral reefs, the cleaning behaviour of certain species represents an important interspecific and mutualistic relationship that provides a vital ecological service to the wider reef fish community. In the Caribbean, cleaning is performed by both fish (primarily gobies of the genus Elacatinus) and invertebrates (primarily the Pederson cleaner shrimp, Ancylomenes pedersoni). Cleaner species occupy cleaning stations that are sought by client fish who perform set behaviours in order to initiate cleaning. The dynamics of these interactions are complex, and span the taxonomic spectrum of the reef fish community, with Pederson cleaner shrimp alone known to service over 20 families of fish. After mapping the cleaning stations present at a site, students will use remote video observations to explore patterns in cleaning behaviour involving shrimp, gobies or both. Projects could focus on drivers of clientele composition, or how cleaning frequency and duration varies between client species. Alternatively, projects could build on recent research demonstrating the impact of diver presence on the provision of cleaning behaviour through a combination of in water diver observations and remote videography.

HO20 Physiology and behaviour of the long-spined sea urchin, a keystone Caribbean coral reef herbivore

The long-spined sea urchin (Diadema antillarum), is responsible for the maintenance of coral reef health throughout the Caribbean. However, in the early 1980s a region wide epidemic reduced their populations by an average of 98%, which stimulated the widespread macroalgal phase-shifts that currently plague the Caribbean. Despite the fact that restoration of D. antillarum is widely believed to be a conservation priority we know surprisingly little about their physiology and behaviour. The aim of this project is therefore to explore the innate responses of this keystone species to numerous external environmental and physical factors, such as food and habitat availability, rising sea surface temperatures and ocean acidification, which may affect the success of targeted conservation efforts. These questions will be answered through a series of laboratory manipulations on urchin specimens collected from nearby reefs.

Extended Project Summary

HO21 The behaviour of invasive lionfish on Caribbean reefs

The invasion of lionfish in the Caribbean has developed into one of the greatest threats to the survival of the region’s coral reefs thanks to the devastating effect they have on native fish populations. Research has naturally focused on mapping the spread of lionfish, quantifying their ecological impacts, and exploring management interventions to reduce their numbers. However, improving our understanding of the behaviour of this species on non-native reefs is of particular interest to better grasp the underlying success of their invasion. This project will assess lionfish behaviour both on the reefs and in a small laboratory, where individuals will be captured and processed. Particular focuses of this work could include prey selectivity, and habitat preferences to investigate the cryptic nature of this species, and data can be linked to ecological characteristics of the reef itself.

Extended Project Summary

IN24 The feeding behaviour of herbivorous fish and their role in maintaining the reef

Reef building corals are the foundations of coral reefs. They produce the physical structure and complexity that provide habitat for the many thousands of species. However their abundance is greatly threatened and as environmental conditions change we see other benthic taxa starting to outcompete corals and dominate which can lead to new less biodiverse alternative ecological states. Shifts from one dominate state to another are often termed phase shifts and knowledge of the key factors that increase and / or decrease the probability of such phase shifts occurring are desperately needed so that direct conservation action can intervene to prevent a net reduction in reef biodiversity. The shift from coral to algal dominance has been well documented in the Caribbean and appears commonplace. However, on the mega biodiverse reefs of the coral triangle there has been no such shift. One hypothesis is that the feeding rate and behaviour of herbivorous fish reduce the ability of algae to become dominant. There is thus an urgent need to quantify the amount of herbivory occurring on reefs of the Wakatobi using a combination of behavioural-based studies of specific key herbivores and assessment of actual grazing rates occurring per unit area of reef. Recent research has suggested that the presence of key predators of fish can influence herbivore feeding behaviour. Therefore further studies could also examine how the presence of large predators such as large emperors, snappers and giant-and/or blue fin trevally influence the behaviour of herbivores. Other studies could use caging experiments to examine how the removal of herbivore pressure influences changes in algal biomass. This is an extremely important piece of research that will help identify the key issues facing the reefs of this biodiversity hotspot. Information gained will feed directly in to predictions of future health and help inform effective conservation strategies.

IN26 Hide and seek: behavioural characteristics of fish living within coral colonies

Many species of fish live within the colonies of branching and tabulate corals. These fish often belonging to the damselfish family, most often live in large groups and seek refuge within the complex structures provided by these colonies. Such colonies, most often belonging to the genus Acropora are vulnerable to thermal events, sedimentation and turbidity. There is a need to understand the specific relationship between corals and their resident fish, in particular how environmental conditions influence coral colony morphology and how this influences the resident fish assemblage. Many species that inhabit coral colonies are juvenile or sub adults, whilst other species inhabit colonies throughout all life stages. The behaviour of different species and how this varies with life stage is of scientific interest as such behaviour is key to the success of these fish within reef systems. The flight response of fish and how this varies across environments will enable researchers to gain a better understanding of the importance of coral colonies for the ecological success of fish as well as providing new insights in to the behavioural ecology of key fish species. This research could examine the distribution of different reef fish species that inhabit branching and table corals and how this varies across with colony morphology. Other projects could examine the flight response of the resident fish by examining the speed and patterns of escape from potential threats. Preliminary investigations suggest that the flight response of juveniles differs greatly from adults particularly as it concerns the time it takes for fish to emerge from the coral colony when a threat is removed or how close a threat needs to be to elicit a flight response of fish which retreat in to the coral to seek refuge. This project offers a unique opportunity to examine specific behavioural traits, how they vary across species and life stages and to examine the unique and complex interactions between fish and reef building corals on the most biodiverse reef system in the world.

IN27 Behavioural adaptations of dwarf cuttlefish, Septa bandensis

As a group, cephalopods display a high level of nervous integration resulting in complex behavioural responses and social interactions that rival those seen in higher vertebrates. The Wakatobi National Park is home to at least 30 cephalopod species, many of which can be found inhabiting reef and reef-associated habitats. The dwarf cuttlefish (Sepia bandensis) is the most abundant cephalopod species found in the park, occurring in large numbers near rocky shorelines, on coral rubble, in seagrass meadows and at mangrove margins. While the species has some minor commercial value in local artisanal markets, its major importance lies in their ability to shape habitat ecology by indiscriminately preying on large numbers of small to medium sized crustaceans. In spite of their ecological importance, little is known about the feeding behaviour or social interactions in this species. The primary objective of dissertation projects could include aspects of feeding behaviour, effects of competition, and social interactions between individuals of different gender and/or size. Other studies may be considered but require approval of the field supervisor. All studies would be conducted using captive animals housed in the Hoga Island Research Laboratory and proposed studies must be non-lethal. Students must also check with their university advisor regarding their universities policies and procedures for working with cephalopod animals. Students are strongly encouraged to contact their project field supervisor early in the proposal development process.

Extended Project Summary

IN28 The complex behaviour of coral reef fish in a mega biodiversity hotspot 

The behavioural characteristics of reef fish are complex and largely dictate the success of a species within the highly competitive reef systems of the coral triangle. Behaviour is plastic, varies in response to environmental conditions and has evolved to enhance the fitness of the individual. An evolutionary strategy for many species existing within mega biodiversity hotspots such as those of the Wakatobi is to form mutualistic relationships with other species. Mutualistic relationships appear commonplace but perhaps the clearest example are those that exists between anemones and their inhabiting anemonefish species. A recent study demonstrated that reefs of the Wakatobi have unique levels of cohabitation of anemonefish within a single host anemone. On reefs surrounding Hoga the prevalence of cohabitation is the highest in the world but the costs and possible benefits of cohabitation is yet to be ascertained. Research could examine the implications of cohabitation as it concerns reactions to predators or opportunities for anemonefish species to defend larger territories. Another common mutualistic relationship between fish species are the complex interactions between cleaner species and their clients. The reefs of the Wakatobi have several cleaner fish species as well as cleaner shrimps but it is uncertain whether these different cleaners partition their clients or whether the most abundant cleaning species i.e. the bluestreak cleaner wrasse is dominant because it provides the highest quality service to its clients. The implications of degrading habitats on cleaner density and service provision is also unknown although it may be expected, unlike most other species, that cleaner abundance may actually benefit from a degraded system. The more researchers examine species of reef fish the more complex behavioural traits are discovered. For example recent preliminary research has demonstrated the diverse behaviour of the commonly encountered trumpetfish previously considered to be a relatively sedate species. However it now appears that trumpetfish commonly display a range of complex behaviours which include ambush predation, utilising other fish species to hide whilst stalking prey, using colour changes to hide from prey items and utilising stealth and ambush feeding strategies. However research is preliminary and further studies are required to really describe the behavioural ecology of this charismatic species. Overall dissertations in this research area will provide great insight in to the strategies employed by resident species to increase their chance of survival in the most biodiverse and competitive coral reef systems in the world.

MA41 The impact of human-animal-interactions on the behaviour of lemurs in Mahamavo, NW Madagascar

The scientific study of human-animal interactions (HAI) has developed drastically over the years from initial investigations into agricultural, companion and now zoo animals. These investigations focus on captive managed animals, which are bred in these conditions and potentially more accustomed to human presence. Wild animals, however, are not and with the number of HAI between wild animals and humans due to an increase in eco-tourism and general living in and around areas normally habited by wild animals, these have a potential to have a greater impact and influence conservation strategies of threatened species. Studies have highlighted that for various species, these close living arrangements and/or close encounters between wild animals and humans can have significant negative effect on the animals’ spatial response, reproductive success and behaviours. Current research has investigated human presence and disturbance impacts of a handful of bird and reptile species, the hermit crab and ten species of North American mammal, but no current research has investigated the potential impacts on threatened primate species or species that have the potential for eco-tourism impact. This project aims to investigate what, how and why impacts of human presence have on a variety of lemur species living in the forests.

MA42 Regional biogeography, ecology and behaviour of nocturnal lemurs in the dry deciduous forest of northwestern Madagascar

Lemurs are 100% endemic to Madagascar and are confined to the remaining forest habitats of the island. They are a highly diverse taxonomic group (>100 species) and at the same time the most threatened group of mammals with about 94% of all assessed species being categorized as either vulnerable, endangered, or critically endangered (IUCN, July 2012). In this situation it is of utmost importance to understand their local and regional distribution as well as the behavioural constraints, ecological plasticity and ecological requirements of each lemur species in order to determine their vulnerability towards becoming extinct in the near future. Among the nine lemur species that have been reported from the Mariarano area, six are nocturnal (Microcebus murinus, M. ravelobensis, Cheirogaleus medius, Phaner pallescens, Lepilemur edwardsi, Avahi occidentalis). Nocturnal lemurs are generally much less studied than their diurnal cousins but face the same anthropogenic threats. They are therefore chosen as models for this project. The aim of this research is to study the abundance, spatial distribution, ecology, and behaviour of three different nocturnal lemur genera (Microcebus spp., Lepilemur edwardsi, Avahi occidentalis) in various forest fragments in the Mahamavo region, northwestern Madagascar.

Extended Project Summary

ME49 Spider monkey grouping patterns, habitat use and behaviour

Spider monkeys are frugivorous primates that live in complex societies characterised by high degree fission-fusion dynamics whereby members of the same community are rarely all together and spend their time in fluid subgroups that constantly change in size and composition. Subgroup size is adjusted to food patch size and when fruit is abundant the spider monkeys can be found in large groups. Group size and composition can have a notable effect on activity budgets, ranging and social interactions, particularly as there are notable sex-differences in the quality of social relationships and the type of social interactions exchanged by males and female. A large community of spider monkeys in the Calakmul Biosphere Reserve has been studied each summer since 2013. The summer months are associated with the onset of rainy season and high fruit production resulting in large subgroups of spider monkeys. However in 2014 the reserve suffered a severe drought and during this time virtually no fruit was available. Using the long-term data set students can investigate changes to ranging patterns, subgroup composition and the associated effect on rates of social interactions in relation to rainfall patterns and food availability. Another project could focus on spider monkey activity and habitat use. Spider monkeys can have large home ranges that encompass different forest types, but it is not clear if they use all forest types for food and shelter. An investigation of how spider monkeys use the different forest types will determine whether spider monkey populations could survive in disturbed areas with limited availability of high forest. Activity budget data will be recorded using instantaneous scan sampling, noting the behaviour of each individual in view, the GPS location and forest type. Subgroup composition will be recorded in real time throughout the day and all occurrences of social interactions will be recorded noting the individuals involved, behaviour and context.

Extended Project Summary

PE65 Behavioural changes during interspecific associations of primate groups in the Peruvian Amazon

Interspecific associations are frequently observed between the various primate species found in Pacaya-Samaria Reserve, and the most frequent of these associations is between capuchin and squirrel monkeys. Living in groups has numerous benefits for individuals, including protection from predation and access to potential mates, but also has costs such as increased competition for food resources. In species which live in groups, such as primates in the Peruvian Amazon, the benefits of group living is assumed to outweigh the costs. Whether and how these costs and benefits change when a group of primates associate with another group of primates of a different species is not well understood. This project looks at how the behaviour of capuchin and/or squirrel monkeys changes, depending on the degree of association with individuals of the other species. Various aspects of monkey behaviour can be investigated, for example, looking at whether time spent being vigilant or feeding, or the type of food consumed changes with distance from individuals of other species. Upon locating a group of either capuchin or squirrel monkeys, the monkeys will be followed for as long as possible, and behavioural data will be collected using focal samples. Additional information, such as distance to the closest individual of another species, and the direction of movement of the whole group will be recorded.

Extended Project Summary

SA66 Assessing the ranging patterns and habitat use of African elephants in fenced reserves

Despite continental declines, elephant populations in South Africa are among the healthiest in the world. Many small, private game reserves promote high elephant densities as they are a huge draw for tourists. However, the reserves are almost always fenced, which restricts the natural movement of the elephants and can lead to the occurrence of negative human-elephant interactions. To mitigate conflict, it is important for the reserve management to understand these movements and the motivations behind them. Opwall and its partners are working in reserves across South Africa and Swaziland to assess the behavioural impacts of high local elephant densities. GPS location data on the elephants is collected daily and can be used to assess elephant ranging patterns in relation to other herds/individuals, human habitation, water sources or artificial barriers. Students will also collect detailed data on the elephants’ impact on the reserve through vegetation surveys. These surveys are carried out in all major habitat types found within the reserve and the data can be used to assess the elephants’ habitat usage and preference.

SA67 Assessing human-wildlife interactions in Dinokeng Game Reserve 

Dinokeng Game Reserve is a 18,500 ha reserve that straddles the Gauteng and Limpopo provinces of South Africa. At just five years old, Dinokeng is one of the youngest provincial reserves in South Africa and represents a novel model for game reserve creation. Dinokeng was formed through the donation of land from multiple small and large landowners in the area, many of whom still live within the reserve in fenced homesteads. Along with these homesteads, there are several lodges within the reserve and a self-drive route that tourists can explore unaccompanied. This means that in certain areas of the reserve, human activity levels are high and interactions with wildlife common, leading to potential human-wildlife conflict. From roadkill to fence breakages, Opwall and its partners are currently monitoring these human-wildlife interactions to better understand the dynamics of the reserve. We also collect data on vegetation types, bird diversity and large mammal distributions, which can be combined with the data on human-wildlife interactions to identify patterns and associations between these factors. Detailed maps of the reserve are available that allow for distribution mapping and relation of interactions with physical boundaries such as roads and fences. The findings of this study will help inform reserve managers across southern Africa as reserves are increasingly surrounded by dense human populations.