We are now developing a Komodo dragon population management protocol that provided for the Komodo National Park authority. This draft is need to be further developed, therefore any suggestion are most welcome... to give comment or suggestion, please email us at komodosspi@centrin.net.id or mjimansyah@yahoo.co.id, or phone +62 361 7420434, or fax +62 361 710352.
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DRAFT :
KOMODO DRAGON (Varanus komodoensis) AND TERRESTRIAL WILDLIFE
MANAGEMENT GUIDELINE
Introduction
A guideline is crucial to be developed as reference for the management of Komodo dragons, associated prey species, and their habitat. The guideline is provided for the management authority in response primarily to these following management issues:
· Declines in populations of Komodo dragons;
· Declines in populations of prey populations of Komodo dragons;
· Declines in habitat of Komodo dragons or their prey;
· Disturbances to Komodo dragons during mating;
· Disturbances to nesting females;
· Feeding of Komodo dragons – should this be allowed, and if so under what circumstances should it be allowed and what conditions?
· Creation of new ponds and the maintenance of existing ponds;
· Frequency of monitoring and management of data; and
· Translocation of dragons between islands and/or the mainland.
Current Status of Komodo dragons and affecting factors
Komodo dragon (Varanus komodoensis) is listed in the Appendix I of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) and classified as Vulnerable by the International Union for the Conservation of Nature and Natural Resources (IUCN 2000). The range of the Komodo dragon has decreased significantly over the last three decades due to several threatening processes including the suspected decline of large prey, such as Timor deer (Cervus timorensis) and anthropic habitat fragmentation and disturbances. Degradation of the environment is considered to be a major threatening process that could influence the viability of the extant dragon populations.
POPULATION DENSITY
Density estimates of Komodo dragons were significantly different among four major islands in the Komodo National Park. Population density on Rinca (30.58 ind/km2) was significantly higher compared to the three other islands (18.82, 13.38, and 11.80 ind/km2 for islands of Komodo, Gili Motang and Nusa Kode respectively). Population abundance was varied among island with the highest was in Rinca (1046) and followed by Komodo (672), Gili Motang (127) and Nusa Kode (87) (Table 1). Dragon density estimates were significantly correlated to the density index of deer on each island. Insular population estimates of Nusa Kode and Gili Motang approximate or fall below several theoretical thresholds used to flag extinction proneness. Demographic stochasticity is usually the major component threatening population viability when the population size is in the order of 100 individuals or smaller.
Island | Size* | Density (ind/km2) | Abundance** |
| Komodo | 35.71 | 18.82 | 672 |
| Rinca | 34.21 | 30.58 | 1046 |
| Motang | 9.48 | 13.38 | 127 |
| Kode | 7.3 | 11.8 | 87 |
Table 1. Density and abundance estimation of Komodo dragon in the Komodo National Park
* Obtained by measuring valleys that similar to study sites
** Results from extrapolation
REPRODUCTION AND ANNUAL RECRUITMENT
Komodo dragons displayed a declining trend in female nesting activities. In 2002, twenty seven (27) nests were recorded active, in subsequent years, the numbers declined to 22, 17, 17, and 7 in 2003, 2004, 2005, and 2006 (Figure 1a). Annually, 12 – 36 hatchlings are emerge from nests in February or March (averaged 19 hatchlings per nest per year) as new recruitment. Female’s reproduction related-activities was varied between months and showed a significant changes between July – September (Figure 1b). During the nesting activity, a female spend more energy to build and guard her nest and appears associated with a period of reduced feeding as females are observed to decrease weight (on average 3.42 kg). The interesting interval for females is variable, with only one female recorded nesting in 4 consecutive years, two females were active for two consecutive years; most females were recorded active only once. This suggests that most females are breeding less than annually.
SPATIAL MOVEMENTS AND ACTIVITY AREAS
Movement of hatchlings from their nests was largely linear consistent with natal dispersal. Rates of daily movement and size of activity areas in hatchlings were significantly less compared to juveniles (Table 2). However, habitat use in both classes of immature Komodo dragons was similar, both preferentially utilizing dry monsoon forest over other more xeric habitat types. During their early life stage hatchlings were predominantly arboreal compared to juveniles, and the degree of arboreal activity was strongly correlated with an individual’s size.
In adults, both female and male Komodo dragons displayed monthly variation in the daily movement and size of activity area (Figure 2). Nesting females exhibited nest-centered activities during the nesting period (August to December). Nesting females increased their rates of daily movement and size of activity areas after the third month. However, their core areas were not significantly different between months. Rates of daily movement in Adult male Komodo dragons varied among months. The highest movement rates were recorded in June, when the mating season begins and the lowest were in September, when the mating season ended and the females started nesting.
In general, rates of daily movement and activity areas in larger Komodo dragons were significantly larger compared to small dragons. Distance of movement and size of activity areas were significantly correlated with individual’s body size (Table 1). These distinct differences in spatial ecology suggest important changes in selection pressures operating on different size classes of Komodo dragons.
Table 2. Size, distance and size of activity areas of Komodo dragons.
ANNUAL PREY DENSITY Annual density indices for large prey of Komodo dragons, Timor Deer (Cervus timorensis), indicated fluctuating trends over the last four years and potentially in decline. Overall prey density was correlated with island area with deer density on the larger islands of Komodo and Rinca been significantly higher than that of the smaller islands. The highest average density for deer was recorded on Komodo island (27.37), whilst the lowest was on Gili Motang (5.63).
Major threats - Biological and ecological constraint
As other reptiles, Komodo dragon has a very limited number of hatchlings that survive become adult as high mortality during the first age. Young Komodos are threatened by predation, cannibalism, and also extreme weather condition (e.g. hard-contiguous rain). Yet, survivorship of Komodo dragon is still unknown by scientist yet and require further study.
- Decreasing on reproduction rate
Declining in reproduction rate can be recognized by decrease in number of annual active nest and in turn reduce number of recruitment into population. This pattern is driven by Females are also known decreasing its body condition during nesting period and reduce its reproductive ability. The decreasing is correlated with the availability of deer as main prey of female Komodo dragons. Females require source of energy to recover and prepare them for nesting.
- Declining in key prey species population (Timor deer)
Deer population is also known correlated to the insular population of Komodo dragons body condition and population size. It is also believe that disappearance of resident Komodo dragons on Padar Island is stemmed from the decline of Timor deer (Cervus timorensis) populations due to illegal hunting. It was reported that there were at least 37.5 % cases of law violations in Komodo National Park between 2000-2001 was illegal deer poaching. Deer population also threatened by the existence of exotic species such as feral dogs, particularly on Rinca island.
- Grassland fires
There are number of forest fires incident happened within last decades. During 2002-2006 at least six grassland fires occurred within Komodo National park. The fires could affect the wildlife and habitat composition. Event though some grass or shrub species are fire-adapted and could contribute on regeneration of habitat, nevertheless major threats that from fires is not to the savanna but to the adjacent forested areas. Fires could degrade suitable habitat for Komodo dragons and its associated prey species. Fires could be deliberated by natural causes (extreme dry condition) and human (fires for poaching deer, extracting honey bee).
- Illegal logging
Villagers are extracting logs as their firewood, housing, carving and boat materials even though it is prohibited. There were several illegal logging cases, particularly in Loh Liang, Loh Lawi (Komodo island) and Gili Motang island, occurred between 2003-2006. Damages that caused by this activity, in turn, could risk Komodo dragon population. Trees are important for Komodo dragon as sleeping shelter and hiding place from predator for hatchling and juvenile, and provide shade during hot day. Trees also used as shelter by deer which mean can provide source of food for Komodo dragons.
- Unsustainable fruit harvesting
Villagers are harvesting tamarind fruit mostly in July and August. Uncontrolled harvesting activities can affect in reducing food resources for Timor deer population, and disturb arboreal Komodo dragons. Numerous people that involved during the harvesting process could also increase disturbance to the wildlife and habitat.
- Exotic species
Feral dogs are known existing in the wild, particularly on Rinca island and occasionally hunt for deer and suspected as one of young Komodo dragons predator or competitor for adult. During 2002-2004 cactus were found and spread in Loh Buaya. This exotic plan was so dominating and reduce suitable habitat for Komodo dragons. With a specific insect that could kill cactus, this exotic plan can be eliminated from Loh Buaya. Those are as example how exotic species can be a threat to terrestrial wildlife and particularly Komodo dragons.
- Lack of terrestrial and remote areas security system
Terrestrial and remote areas (Gili Motang) surveillance was not as frequent as marine surveillance. This lack could increase human disturbances that can increase risks of illegal wildlife poaching, habitat fires, illegal logging.
Proposed Management guidelines
To assist park authority, we propose several efforts that could be implemented in managing the extant population of Komodo dragon and its associated terrestrial wildlife and habitat. It is should be underlined that, to increase local community’s participation in protecting wildlife and habitat, involving villagers are important in every level of management activities.
1. Habitat protection and management
1.1. Prevention on forest fire and illegal logging;
à Educate local people to not to use fire next to either grassland or forest and increase their participation on fire extinguish incident.
à Educate local people to not extract live tree, and offer alternative of wood for their needs, i.e solar, gasoline, etc.
à Educate visitors to not to use fire along path or during their visit.
à Regular surveillance across terrestrial areas with particular land patrol on high risk spots and law enforcement.
à Train park rangers and villagers in fire fighting techniques and provide fire fighting equipment which should be kept ready at any time (backpacks, machetes, shovels, , face masks, personal equipments).
1.2. Manage fruit harvesting activities by villagers
à Managing occasion and specific areas that compensated for villagers to harvest fruits from the park. In Loh Liang, it is recommended to assign Loh Bube and Loh Kubu (Eastern Loh Liang) as traditionally areas for fruit, particularly tamarind, harvesting.
à Regular surveillance across terrestrial areas with particular land patrol on high risk spots.
à Educate villagers to harvest natural fruits form the wild within allocated areas for harvesting and by mean of sustainable harvesting techniques without causing any damages to habitat.
1.3. Monitor impact from tourism activity
à Tourism activity will affect on environment and its wildlife, including establishment of facilities. Impacts that caused by should be minimize and monitored to ensure that this activity minimize disturbance to both animal and plans.
à Educate visitors and guides to not disturb animals or plans during their activities.
à Study effective number and appropriate timing for tourist that allowed visiting into the wild. It is necessary to reduce disturbance to animal, especially during breeding season.
1.4. Habitat rehabilitation
à Habitat rehabilitation efforts should only be undertaken in severely damaged areas to recover their original condition. Only native species should be planted and, if possible, seedlings should be obtained from adjacent areas.
à Prior to any large scale rehabilitation, a pilot study should be undertaken to study the success level.
à It is also necessary to design the rehabilitation to mimic natural succession pattern and species association.
2. Wildlife management and monitoring
2.1. Intensive monitoring on terrestrial wildlife
à Intensive monitoring activities on terrestrial wildlife should be carried out with particular reference to study and monitor annual trends on Komodo dragon population, reproduction ecology, growth rate, prey availability (including large and small mammals, reptiles), and change of threat risks. This kind of monitoring should be undertook with yearly basis
à Intensive monitoring activities should be also highlight Gili Motang population, due to its remoteness, high risks of local extinction of Komodo dragon populations, and lack of management implementation in the past.
2.2. Restricted supplemental feeding strictly only for nesting female during nesting period to maintain its condition to prepare nest, lay eggs, guarding nest, and reproduce again on next breeding season;
à A very strict supplemental feeding may be given to only nesting female. This can be only given to nesting females which is in a very poor condition. Supplemental feeding can be only given once a month at the most located near nesting female in order to give energy for female to recover from its severe lack of nutrition during nesting period.
2.3. Intensive surveillance activities, with particular reference on the western part of Komodo and Rinca island and on the smaller islands of Gili Motang and Nusa Kode to prevent wildlife and habitat disturbances;
à Related surveillance activities, such as regular terrestrial and remote areas patrol, should be established and maintained to ensure security and prevention from illegal poaching, forest fires, and illegal logging. This activity can also be benefit in eliminating exotic animals, e.g feral dogs. Surveillance activities should be done with monthly basis.
2.4. Establish and maintain artificial water hole (ponds) within Komodo dragons “hot spot” and near nesting areas for females;
à Establishing artificial water ponds are necessary to attract and increase wildlife presence. Concentrated animal near ponds can be benefit as source of food (prey) for nesting Komodo dragons and tourist attraction.
2.5. Intensive control of pests and exotic species (e.g. feral dogs, cats).
à Exotic species should be controlled or even removed to reduce disturbance to native species by capturing or eliminating efforts.
2.6. Implementation of long term population monitoring
à Long term monitoring would ensure that managers have robust data to address population trends and decide which conservation options that the most appropriate. Population monitoring should be done with at least for every three years.
2.7. Regular monitoring program to observe further changes (decline or incline) of Komodo dragon’s population, prey species, predator, habitat, and environmental condition (climate);
à Regular monitoring on affecting factors to the Komodo dragon population is essential to anticipate any changes which effecting the population.
à Monitoring programs should be implemented in regular time basis and refer to monitoring guideline.
3. Human-wildlife interaction Management
3.1. Intensive monitoring to observe impact from ecotourism activities within tourism areas.
3.2. Limit number of tourism activities around active nests during nesting period
à Limit and arrange number of visitors and visiting time within concession areas.
3.3. Establish alternative tourist paths and observation stations
à Alternative tourist path are necessary to established as substitute to the existing paths that crossing or near Komodo dragon’s nests is essential to construct and utilize during nesting season to reduce disturbance to females;
à Establish observation stations, i.e. near Komodo dragon nest, would be useful to allow visitors in observing female’s activity during nesting period and to observe other wildlife and their interaction. It is also would be useful to reduce impact from human-wildlife interaction.
3.4. Improve tourist education to reduce perturbation to the habitat, including wild fauna and flora, particularly the Komodo dragon.
à Educate visitors to not disturb wildlife and habitat during their visit, including prevention from fires, rubbish management, and interact with Komodo dragons and other wildlife.
3.5. Increase local community participation in protecting habitat and wildlife
à Increase local community’s awareness to increase their responsibilities and participation in habitat and wildlife protection
à Provide alternative income to reduce disturbance on habitat from harvesting actitivies.
4. Species Translocation
Translocation might be needed to recover a severe declining population and as the last option and other conservation has failed. As translocation process may risks remaining population at targeted location, this option should be undertaken only as a measure of last resort as natural restocking. This option could be only chosen if indispensable to recover population declines.
4.1. Translocation of ungulate, i.e. Timor deer, to Gili Motang to increase prey availability for Komodo dragon on this island. This option should consider following issues prior to implementation:
à Develop a strict standard procedure of relocation as this option is strictly chosen as last alternative as other measurements are fail, including pre release and training facilities and procedure.
à Conduct detail habitat assessment, prey population capacity, existing Komodo dragon population and carrying capacity on release site.
à Ensure the individuals that are translocated have the most genetically and ecologically analogous and in a very health condition between source and targeted population.
à Develop a reliable monitoring and security system.
4.2. Translocation of Komodo dragon individuals from high density islands and/or Indonesian zoological gardens to low density islands(s) as reservoir for the long term maintenance of genetic variability and prevent local extinction. However this option should consider these following issues prior to implementation :
à Develop a tight standard procedure of relocation as this option is strictly chosen as last alternative as other measurements are fail, including pre release and training facilities and procedure.
à Conduct detail habitat assessment, prey population capacity, existing Komodo dragon population and carrying capacity on release site.
à Ensure the individuals that are translocated have the most genetically and ecologically analogous and in a very health condition between source and targeted population.
à Develop a reliable monitoring and security system.
Further research / monitoring
There are numbers of research and monitoring should be carried out in the future to investigate several issues that contribute to the management of the extant population of Komodo dragon :
- Develop population models for Komodo dragon
- Investigate age-specific survivorship
- Investigate breeding participation rates of adult females
- Annual estimation on population demography
- Levels of Komodo dragon migration between islands
- Investigate annual trend on recruitment (number of clutches)
- Annual trend on nesting activity
- Annual trend on prey (ungulates, small reptiles, avian)
- Investigate competition between Komodo and other species, i.e wild boar.
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