Project 3: Maliau Basin


Diversity and Abundance of Rattan in Logged and Unlogged Forest

Benjamin Gutierrez1, Dwi Susanto2, Eni Hidayati3

  1. Department of Organismic and Evolutionary Biology, Harvard University
  2. Department of Biology, University of Indonesia
  3. Department of Forestry, Gadjah Mada University, Bulaksumur, Yogyakarta, Indonesia

pdfA study on the effects of logging on rattan species diversity, abundance, and composition in mixed dipterocarp forest in Malaysia, Borneo. Data was collected from belt transects which were placed along skid trails in logged forest and hiking trails in unlogged forest. In addition to diversity, abundance, and composition measurements, the number of stems per individual and the life stage of each individual were also recorded. No statistically-significant differences were found between the logged and unlogged forest. Unlogged-forest transects did not cluster together on the basis of species composition, and neither did logged-forest transects. However, four logged-forest transects were omitted because no rattans were found, as was one unlogged forest transect. Because all four of these logged-forest transects were located along flooded, swampy skid trails, and because the one unlogged-forest transect was located along a river, the authors believe that logging may negatively affect the establishment of rattans due to the poor drainage of skid trails.


Intraspecific and Interspecific Competition for Breeding Site among Three Species of Libellulidae in Maliau Basin

Wulan Pusparini1, Nayana Wijayathilaka2, and Nur Edna Hasreena Ahlun3

  1. Yayasan Badak Indonesia (Rhino Foundation of Indonesia), Jl. Ir. H. Juanda No. 15 Bogor, Indonesia
  2. Department of Zoology, University of Peradeniya, Sri Lanka
  3. Universiti Malaysia Sabah, Locked Bag 2073, 88999 Kota Kinabalu, Sabah

A study on competitive behavior among three dragonfly species (Neurothermis ramburri, Orthetrum chrysis and Tyriobapta torrida) was conducted along the trail to Belian Camp in the Maliau Basin Conservation Area. Two sampling sites were set up to observe the the perching behavior of the dragonflies. From general observations, it is known that all three species of dragonflies exhibit a more aggressive behavior to intraspecific competition compared to interspecific competition. A map of the dragonflies' perching site was modeled based on the observation done. There was no significant difference in flying and chasing behavior between the three dragonfly species. However, there was a significant difference in the time spent perching between the three species with Orthetrum chrysis being the species that spends most time perching as compared to the other two. The study also shows that the dragonflies exhibit a more aggressive intraspecific competition behavior compared to interspecific competition. Due to this, all three species co-exist in the same water body, not competing with each other for breeding group, but competing among the member of their own species.


Comparison of Dusky Munia (Lonchura fuscans) Time-budget Allocations with Respect to Proximity to Human Settlements

Ayu Savitri Nurinsiyah1, and Shreekant J. Deodhar2

  1. Department of Biology, Padjadjaran University, Jl. Raya Bandung Sumedang Km. 21, Jatinangor, West Java 45363, Indonesia
  2. 2 Center for Ecological Sciences, Indian Institute of Science, Bangalore – 560 012, India

pdfA behavioral study regarding time budget allocation of one of Borneo's endemic birds, Dusky Munia (Lonchura fuscans), was conducted at the Maliau Basin Conservation Center, Malaysia. The study evaluates whether or not the birds behave differently when located near or away from human settlements. Two monitoring sites were chosen with respect to proximity to human settlement. Observations were done in the morning as well as in the evening so as to avoid a bias – if any – due to the time of the day. Activities recorded include moving (M), eating (E), resting (R), being actively vigilant (V) and other activities (ETC). Results indicate that Dusky munias allocate more time for R and less time for M when present near human settlements; the scenario being reversed when the birds are away from human disturbances. This can be attributed to the shy nature of the bird, as it may prefer hiding and lesser movement when present near human settlements. No significant differences were seen for V and E activities between the two locations.


Composition of Scavengers in the Canopy and Understory

Alan C. Chiu1, Justine S. Chow1, and Cindy J. Liu1

  1. Department of Organismic and Evolutionary Biology, Harvard University

pdfThe degradation of dead organic matter by scavengers is an important step in the circulation of nutrients in all ecosystems. In tropical rainforest ecosystems, the canopy and understory are two very different environments and thus would be expected to contain differing levels of scavenger species abundance, diversity, and composition. Four uniform traps were used to collect specimens for this experiment. The experiment focused on examining differences that arise between different bait types, times of day, and forest canopy vs. understory. Significant results were found when comparing overall abundance and time of day, diversity and type of bait, and ant and fly composition and forest level.


The Effect of Bark Type, Canopy Architecture, and Tree Leaf Characteristics on Epiphyte Abundance and Diversity in Maliau Basin Conservation Area, Sabah, Malaysia

Muhamad Ikwan Idris1, Gregory A. Parker2, and Anna M. Ruman3

  1. Department of Zoology, Universiti Malaysia Sarawak, Kota Samarahan, Sarawak, Malaysia
  2. Department of Environmental Management, Harvard University, Cambridge, MA, USA
  3. Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA

pdfAs plants specially adapted to a non-soil substrate, epiphytes face unique challenges to successful growth and propagation. These challenges include balancing light, water, and mechanical stability needs, all of which are closely associated with the characteristics of the epiphyte's host tree. Therefore, we hypothesized that tree leaf type, leaf size, leaf arrangement, bark texture, and canopy branch density would exhibit non-random associations with the abundance and diversity of epiphytes associated with a given tree. We surveyed a 300 m transect of canopy walkway in Maliau Basin Conservation Area, recorded epiphyte counts and identification for 21 trees, and recorded the aforementioned characteristics of each tree. Using ANOVA analysis, we found a significant association between bark type and epiphyte abundance (Pr(>F)=0.024, F-value= 4.0543) and epiphyte diversity (Pr(>F)=0.036, F-value= 3.5696), with smooth bark hosting the greatest abundance and diversity of epiphytes. Furthermore, using generalized linear models, we observed a significant negative association between canopy branching density and epiphyte abundance (p-value=2e-16) and diversity (p-value= 0.000465). Additional research based upon these highly significant results may indicate precise light, water, and mechanical support demands of epiphytes and may have the potential to further elucidate the effects of climate change and of deforestation on epiphyte abundance and diversity.


Comparing the Lichen and Bryophyte Composition between Mid-trunk and Basal Regions on Trees in Bornean Lowland Dipterocarp Forest

Noor M.R. Beckwith1, Kwek Yan Chong2, and Will Skinner1

  1. Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA
  2. Department of Biological Sciences, National University of Singapore, Singapore

pdf The trees supporting the SkyBridge canopy walkway in Maliau Basin, Sabah, Malaysia were studied to determine if lichen and bryophyte composition differs between the mid-trunk (~20 m above ground level) and basal (~2 m above ground level) regions of trees. A circumferential line intersect transect method was used to determine the percent coverage of each bryophyte and lichen morphotype. Multivariate composition analysis revealed that mid-trunk regions clustered separately from basal regions in terms of lichen and bryophyte abundance. In general, bryophyte coverage dominates over lichen in basal regions while crustose lichen dominates in mid-trunk regions. Overhead cover was also significantly positively correlated (p -value = 0.012) with bryophyte abundance. It is proposed that breakage of continuous canopy cover from natural causes or human interference may change the trunk microclimate in a way which favors lichen cover. Further research is necessary to elucidate the effects of other factors on trunk epiphyte communities.


Comparison of Tiger Leech Attraction to Heat and Movement Stimuli in Maliau Basin, Sabah

Karl Kmiecik1, Katherine O'Leary2, and Ling Chea Yiing3

  1. Department of History and Science, Harvard University, Cambridge, MA, USA
  2. Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA
  3. Sarawak Forestry Corporation Sdn. Bhd./Forest Research Centre, Jln Datuk Amar Kalong Ningkan, 93250 Kuching, Sarawak

To determine whether heat or movement plays a larger role in attracting leeches, two separate experiments were conducted. Each experiment consisted of a treated object and control object placed along an open transect. Three sets of 16 trials were performed on individual leeches for each experiment. Results were scored as reacting to treatment, reacting to control, or having no reaction to either. Utilizing Pearson's chi-square test, the results were compared to expected probabilities derived from the experimental design given random behavior. The p-value for the heat experiment was highly significant (p < 2.2e-16). The p-value for the movement experiment was insignificant (p = 0.9687). The results suggest that heat does play a larger role than movement in attracting leeches. However, alternative experimental designs may yield different results, suggesting a need for further research to fully answer the above question.