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A comparative cognition perspective on the production and use of visual signals by African savannah elephants (Loxodonta africana)Smet, Anna F. January 2015 (has links)
Elephants' complex societies, well-developed communication systems, evolutionary history and close working relationship with humans make them an important species for studies of cognition but research on elephant cognition is sparse. In this thesis I aim to illuminate the social cognition involved in the interpretation and production of visual signals by African elephants (Loxodonta africana). My results are intended to contribute to the cross-species literature on social cognition and help to elucidate wild elephant social behaviour. I studied captive elephants, housed at an elephant-back safari company in Victoria Falls, and wild elephants in Hwange National Park, both in Zimbabwe. Wild elephants display a vast array of postures, actions and signals. I found that elephants recognise visual attentiveness in others when they signal silently, producing more signals when their audience can see them, and using the body and face orientation of an audience to judge their attention. When responding to typically human visual signals, elephants immediately responded correctly to deictic gestures, including variants of pointing that they were unlikely to have already experienced. These results indicate elephants' astonishing sensitivity to even subtle social cues. I found no indication that elephants reason about mental states such as false beliefs, or rationality; however, limitations of the experimental design meant I was unlikely to find such an ability even if it is present in elephants. Furthermore, I discovered that elephants have a form of referential indication in their natural communication in the wild. Elephants match their direction of attention with a type of trunk action produced by a group member. Attending to human-like signals, and interpreting them as communicative is an advantage for any animal working with humans and that ability might explain the choice of species that are ancestors of today's domestic animals.
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Bai use in forest elephants (Loxodonta africana cyclotis) : ecology, sociality & riskFishlock, Victoria L. January 2010 (has links)
Forest elephant (Loxodonta africana cyclotis) sociality is relatively little-studied due to the difficulties of making direct observations in rainforests. In Central Africa elephants aggregate at large natural forest clearings known as bais, which have been postulated to offer social benefits in addition to nutritional resources. This thesis explores the role of these clearings as social arenas by examining bai use within three main themes; ecology, sociality and risk factors. Seasonal changes in elephant use of the Maya Nord bai (Republic of Congo) are described, along with the demography of the visiting population. Elephant visit rate was highly variable; the number of elephants using Maya Nord in an observation day ranged from 0 to 117 animals. This variability was unrelated to local resource availability and productivity suggesting that bai use occurs year round. Elephants in Odzala-Kokoua do not show high fidelity to a single clearing; 454 elephants were individually identified and re-sighted an average of 1.76 times (range 1-10) during the twelve month study period. Previous bai studies have yet to quantify how elephants associate with one another within the bai area. This study examines socio-spatial organisation and associate choice using two measures of association within the 0.23 km2 bai area; aggregations (all elephants present in the clearing) and parties (elephants spatially co-ordinated in activity and movement) and distinguishes these from parties that range together (i.e. arrive and leave together). Social network analyses (SocProg) were used to describe inter- and intra-sexual multi-level organisation in the bai environment, and to illustrate the non-random nature of elephant aggregations and parties. Bais were shown to function as social arenas; female elephants showed active choice of certain associates and active avoidance of others when creating parties, whereas males were less discriminatory. Parties formed in the clearing (mean size= 3.93, SE= 0.186) were larger than ranging parties (mean size= 2.71, SE= 0.084) and elephants stayed for 50% longer in the clearing when they associated with individuals from outside their ranging party. Inter- and intra-sexual relationships were maintained within the clearing, and these are suggested to offer elephants essential opportunities for social learning. The patterning and nature of the relationships observed at the Maya Nord clearing indicates that forest elephants use a fission-fusion social structure similar to that of savannah elephants (Loxodonta africana africana); relationships are significantly structured by age- and sex- and underpinned by individual identity. Old experienced females hold key roles for forest elephants, and male relationships are superimposed on the network of female associations. Odzala-Kokoua elephants use bais to maintain their social relationships despite being highly sensitive to the anthropogenic risks involved in using these open areas. The results of this study suggest that forest and savannah elephants lie on the same social continuum, balancing social “pulls” to aggregate against the ecological “pushes” that force groups to fission. Previous models of savannah elephant sociality construct levels of association and social complexity upwards from the basic mother-calf unit (e.g. Wittemyer & Getz 2007). My results suggest that it may be more appropriate to consider elephant sociality and associations as in dynamic equilibrium between social and ecological influences acting at all levels of grouping, and to explicitly test how these underlie the opportunity costs that elephants are willing to pay in order to maintain social groupings.
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Relatedness, social behaviour, and population dynamics of the elephants (Loxodonta africana) of Addo Elephant National Park, South AfricaGough, Katie F January 2015 (has links)
This study presents an investigation into the population dynamics and social structure of a small, closed elephant population. Specifically, it examined population growth rates for evidence of density-dependent regulation. It also quantified the association patterns of female elephants groups, and male elephants groups. Social structure was examined using Hamilton’s kinship theories of inclusive fitness, and age. Male-female patterns of association were also examined for inbreeding avoidance behaviours. The study population was located in Addo Elephant National Park, South Africa. Density-dependence was assessed using a long-term data set. Densities were considerably higher than estimated carrying capacities. Population growth rate was positively correlated with increasing density. No relationship between birth rate, the age of first calving or calf sex ratio and elephant density was detected but there was a positive relationship between birth rate and rainfall during conception year. Mortality rates, particularly for juveniles, were low, and mean inter-calf interval was 3.3 years. There is no evidence of density dependent regulation in this population. These findings indicate that density dependence should not be considered as an option in the control of elephant numbers in this Park, or where elephant resources are not seasonally limited. Examination of association patterns of the adult female component revealed that associations were not random at the population, family or individual scale. This is the second study on African elephants to confirm previous behavioural studies that predicted that preferred associates were close maternal relatives. This supports many studies showing that social species preferentially associate with their kin. The adult males in this population were found to have a well differentiated society with non-random associations. Generally, males were found to have weak associations with most other males and strong associations with only a few males. This association pattern was found to be persistent over the time frame of the study, as indicated by the time lag analysis. Males returned to their natal family, even when maternally related females were in oestrus. Oestrous females directed positive behaviours towards musth males. It appears that behavioural inbreeding avoidance mechanisms in this small, closed population are inhibited: musth status seems to override inbreeding avoidance. General principles from this case study were interpreted in terms of their applicability to other small, closed populations.
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Applying GPS and Accelerometers to the Study of African Savanna (Loxodonta africana) and Asian Elephant (Elephas maximus) Welfare in ZoosHoldgate, Matthew Robert 16 March 2015 (has links)
African savanna elephants (Loxodonta africana) and Asian elephants (Elephas maximus) are a focus of welfare research in zoos due to their high intelligence, complex social structure, and sheer size. Due to these challenges, some argue that zoos are inherently incapable of providing appropriate care for elephants, while others believe that zoos can fulfill the needs of these species with improved husbandry. There is a general consensus from both within and outside of zoos, however, that zoos must improve their elephant programs or cease exhibiting these animals altogether. Now more than ever, applied research on zoo elephant welfare is needed to provide context for this debate.
Researchers are interested in how far zoo elephants walk due to the potential health and welfare benefits of walking in these highly mobile species. Zoo researchers recently adopted GPS technology to study elephant walking, and preliminary evidence suggests that African elephants in large zoo exhibits walk distances that correspond with wild elephants under non-extreme conditions. However, data are limited from Asian elephants and from elephants in more typically-sized exhibits. In Chapter Two, I discuss important methodological considerations of utilizing GPS in a zoo environment, including an introduction to the technology, sources of error and mitigation, methods to improve GPS performance, and possible effects of GPS device attachment on animal behavior. This review shows GPS performance is adequate for tracking zoo elephant walking when proper methodological techniques are applied, and should serve as a useful reference for zoo researchers considering using GPS.
In Chapter Three, I used GPS anklets to measure outdoor daily walking distance in 56 adult female African (n = 33) and Asian (n = 23) elephants housed in 30 zoos. I collected 259 days of data and found that elephants walked an average of 5.34 km/day with no significant difference between species. Multivariate regression models predicted that elephants with more dynamic feeding regimens (more diverse feeding types and frequencies; unscheduled feeding times) will walk more. Distance walked was also predicted to be higher in elephants that spend time in a greater number of different social groups. Distance walked was predicted to decline with age. Finally, I found a significant negative correlation between distance walked and nighttime space experience. The results of the analysis suggest that zoos that want to increase walking in their elephants need not rely solely on larger exhibits, but can increase walking by adding quality and complexity to exhibits. However, my results failed to establish a definitive link between walking distance and other validated measures of elephant welfare. Thus, the direct health and welfare benefits of walking in zoo elephants remain unresolved.
Resting behaviors are an essential component of animal welfare, but have received little attention in zoological research. In Chapter Four, I used accelerometers in anklets to complete the first large-scale multi-species investigation of zoo elephant recumbence. I collected 344 days of data from 72 adult female African (n = 44) and Asian (n = 28) elephants at 40 zoos. I found that African elephants are recumbent an average of 2.14 hours/day, which is significantly less than Asian elephants at 3.22 hours/day. Multivariate regression models predicted that African elephant recumbence increases when they experience more space at night, and Asian elephant recumbence increases when they spend time housed alone. Both species showed a similar response to substrate, such that African elephants spending time on all-hard substrates are predicted to be recumbent less, while Asian elephants spending time on all-soft substrates are predicted to be recumbent more. The discovery that occasional non-recumbence is a common behavior in zoo elephants also introduces a new area of research that may have important animal welfare consequences. Finally, this study established that zoos should continue their efforts to replace hard substrate with soft substrate in order to provide zoo elephants with environments that facilitate recumbence.
Overall, this work assessed walking and recumbence in zoo elephants, which will allow zoos to gauge the prevalence of these behaviors in their elephants as compared to the sub-population studied here. A variety of factors that are associated with these behaviors were also identified. With this information, zoos can prioritize modifications to their facilities and animal management programs to create an environment that encourages zoo elephants to express walking and recumbence behavior, should they choose to do so.
This work is one component of the Elephant Welfare Project, the largest zoo animal welfare project ever undertaken, and is unprecedented in both scope and scale. The project was funded by the Institute of Museum and Library Services (IMLS), an independent, U.S., federal, grant-making agency that supports libraries, museums, and zoos. At the time of this writing, the first manuscripts from this project are being submitted to academic journals. These papers will describe the prevalence and distribution of a variety of elephant behaviors and welfare indicators, serve as a benchmark for future elephant welfare studies, and aid in decision making with regard to best practices in elephant management.
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