CONCLUDING DISCUSSION
5.3 Future Research
The use of different indices of condition found within the literature make it difficult to compare results obtained from various studies. This is especially true for comparisons between visual condition indices and biological condition indices (such as Kidney Fat Index or Bone Marrow Fat). It is suggest that, if culling of elephants were ever to take place, it would be beneficial to look at these more traditional body condition measures and calibrate these with the observed visual body condition estimates. Alternatively, the use of either catabolic breakdown
products in the urine, such as creatinine, or faecal stress hormones (Foley et al. 2000) could be used to benchmark visual body condition scores. This would allow for possible refinement and greater degree of confidence in the use of visual body condition estimates, and would allow for better comparisons of condition obtained via different methods.
One shortcoming of this study was the lack of data on new born calves (i.e. under one year of age), as well as females who were both pregnant and lactating. It is suggested that future research include these two categories, as it is expected that they would be the even more affected by nutritional stress. Additionally, the lack of seasonal replication makes it difficult to track long-term responses and natural variations in condition, and it is suggested that future research follow changes in elephant body condition of a population for at least three years to provide a minimal seasonal replication.
Although my study showed responses in body condition to changes in rainfall, it is suggested that future research measure body condition across a broader landscape with larger differences in soil nutrients and rainfall. This will allow a greater insight into the sensitivity of elephant condition to changes in these parameters. I also suggest that future research compare body conditions of elephants occurring in different biomes, which will give an indication of the responses of elephant condition in various landscapes. Additionally, I suggest that the rate of recovery of body condition should be measured in a system where distinct wet and dry seasons are experienced. This will aid in our understanding of the possible time-lags between observed condition and resource availability.
Lastly, I also suggest that it may be beneficial to further investigate the possible link between critical faecal protein and NDF values and body condition, by using a larger dataset of elephant body condition scores and faecal samples to verify the suggested dietary quality thresholds found in my data. If such threshold
values can be determined it could be possible to predict the body conditions of elephants in a population by the collection and analysis of faecal samples. This would be especially useful for the determination of condition of elephant populations found in the forests of West Africa, which are often hard to observe and study (Merz 1986; Eggert et al. 2003).
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