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Tropical deforestation continues to be a major driver of biodiversity loss and greenhouse gas emissions. Remote sensing technology is increasingly used to assess changes in forest cover, species distributions and carbon stocks. However, satellite and airborne sensors can be prohibitively costly and inaccessible for researchers in developing countries. Here, we describe the development and use of an inexpensive (<$2,000) unmanned aerial vehicle for surveying and mapping forests and biodiversity (referred to as ‘Conservation Drone’ hereafter). Our prototype drone is able to fly pre-programmed missions autonomously for a total flight time of ~25 minutes and over a distance of ~15 km. Non-technical operators can program each mission by defining waypoints along a flight path using an open-source software. This drone can record videos at up to 1080 pixel resolution (high definition), and acquire aerial photographs of <10 cm pixel resolution. Aerial photographs can be stitched together to produce real-time geo-referenced land use/cover maps of surveyed areas. We evaluate the performance of this prototype Conservation Drone based on a series of test flights in Aras Napal, Sumatra, Indonesia. We discuss the further development of Conservation Drone 2.0, which will have a bigger payload and longer range. Initial tests suggest a flight time of ~50 minutes and a range of ~25 km. Finally, we highlight the potential of this system for environmental and conservation applications, which include near real-time mapping of local land cover, monitoring of illegal forest activities, and surveying of large animal species.
Unregulated hunting can severely affect wildlife populations, particularly in the tropics. From May to October, 2011, we documented target species, hunting techniques, and demand and sale of bushmeat from a local community located at the base of a forested National Park on an isolated mountain (over 10,000 ha) in southern Luzon, the Philippines. The prey taken by hunters (i.e., poachers) included 22 invertebrate and vertebrate species. The main prey items were fruit-eating birds, bats, civets and wild pigs, but the most sought-after prey were flying foxes. Money was the major driver of bushmeat hunting in our study area. Bushmeat was sold and consumed almost entirely by residents of the local community and nearby towns, as hunters stated that they do not have demand from regional urban markets. Localized consumption suggests that focused conservation efforts may be effective in reducing the documented hunting pressures. Fines for hunting endangered species, according to hunters, were a deterrent. Because of limited law enforcement in our study area, however, conservation efforts such as teaching local hunters to avoid endangered species or encouraging them to monitor local animal populations may be the best bottom-up approach to minimize the negative effects of hunting.
On 7 February 2012, one of the largest whale sharks ever recorded was found presumably dead and towed to Karachi harbour. On 8 February, ‘whale shark’ was the third most searched keyword as shown on Google Trends. Reports on landmark events such as this could educate the public on marine conservation issues. We collated 45 internet news reports and examined whether or not reports a) are scientifically accurate for information on the species in question and b) educate readers on specific or broad biology or conservation issues. We found only 46.6% of the reports to be factually accurate. Only a minority of the reports discussed conservation of whale sharks. Scientists should step-up public communications as a meaningful educational exercise in light of overwhelming public interest in such events.
Increasing human settlement and disturbance adjacent to protected areas have intensified competition between people and wildlife for resources and living space. In northern Cameroon, over 60,000 people live in villages surrounding Bénoué National Park. In that same area, as in other parts of Africa, savanna elephants damage crops, homes, water provision infrastructures, and grain stores. Using almost 1000 satellite-derived positions for two matriarch female elephants from 2007 to 2009, movement patterns were analyzed with respect to a highway, secondary roads, unpaved park roads, rivers, and villages through the use of log linear modeling. More than half of all locations and core areas occurred outside the park, while seasonal and individual differences in home range size and distribution were found within the protected area. Elephant occurrence within approximately 7 to 9 km of villages showed a decreasing trend with proximity. The highway appeared to act as a barrier to movement for one elephant herd, while the other did not come within 11 km of it. On the other hand, elephants remained close to the Bénoué River and secondary roads. Our findings show that in the Bénoué Wildlife Conservation Area, perennial water availability and human disturbance from the presence of villages can influence elephant spatial distribution in the protected area, and overlap of villages with elephant home range indicates a high potential for human-elephant conflict. This highlights the need for more effective land use planning to reduce such conflict and for additional research into movement patterns of the Bénoué National Park elephant population.
To determine abundance, density and distribution of wild animals, it is crucial to estimate populations using reliable sampling techniques. In most earlier studies, elephant populations were estimated employing block counts or dung counts, which provide biased estimates due to limitations of the methods. We estimated an Asian elephant population using distance sampling, a quantitatively robust technique, in Biligiri Rangaswamy Temple Tiger Reserve, a critical elephant conservation area in the Nilgiri Biosphere Reserve in south India. We laid 33 transects with a total length of 93 km. We walked these transects five to 11 times amounting to a total of 795.5 km of walks. We collected data on location, number and age-sex classes through direct elephant sightings, using rangefinders, global positioning systems and compass. We used DISTANCE software for analysis. We estimated per km2 cluster density as 0.69 elephant herds, mean cluster size as 2.44, and elephant density as 1.7 animals. This amounts to a total of 713 elephants in 610 km2 of the sanctuary. A high percentage of males less than 30 years old and a low immature:adult female ratio indicated the severity of poaching in the recent past in the study region.
Geographically isolated from other C. albifrons taxa found east of the Andes, the Ecuadorian capuchin (Cebus albifrons aequatorialis) is a Critically Endangered primate that survives in a small number of localities in western Ecuador and extreme northern Peru. We assessed 11 forested areas in western Ecuador to determine presence/absence using a combination of on-foot searching and interviews with local informants. C. a. aequatorialis were present at seven of the sites surveyed, four of which represent new presence localities. We carried out extensive censuses of five small, private reserves to obtain estimates of population density and demographic information. We also examined home range characteristics and habitat selection at one well-studied site. Population densities based on absolute counts at these sites ranged from 2-22 individuals/km2 (median = 2.4). Jauneche, a 138 ha isolated fragment reserve with 22 individuals/km2, was a clear outlier. Although we observed some solitary individuals, C. a. aequatorialis live predominantly in multi-male multi-female social groups, with a mean group size of 13.9 (range 5-20). The composition of social groups was typical for Cebus: adult females outnumbered adult males slightly, and groups exhibited relatively high immature to adult female ratios (mean = 1.5). Home ranges were unusually large for the genus (507–561 ha). The capuchins exhibited strongest selection for mature forest near streams, although they also used degraded forest frequently. C. a. aequatorialis faces critical threats in the form of habitat loss, hunting, and harassment by farmers, but we suggest that some remaining populations have the potential to grow if effective protection can be established.
We tested the early performance of 16 native early-, mid-, and late-successional tree species in response to four intensities of grass removal in an abandoned cattle pasture dominated by the introduced, invasive African grass, Cynodon plectostachyus, within the Lacandon rainforest region, southeast Mexico. The increase in grass removals significantly improved the performance of many species, especially of early- and mid-successional species, while performance of late-successional species was relatively poor and did not differ significantly among treatments. Good site preparation and at least one additional grass removal four months after seedling transplant were found to be essential; additional grass removals led to improved significantly performance of saplings in most cases. In order to evaluate the potential of transplanting tree seedlings successfully in abandoned tropical pastures, we developed a “planting risk index”, combining field performance measurements and plantation cost estimations. Our results showed a great potential for establishing restoration plantings with many early- and mid-successional species. Although planting risk of late-successional species was considered high, certain species showed some possibilities of acclimation after 18 months and should be considered in future plantation arrangements in view of their long-term contributions to biodiversity maintenance and also to human welfare through delivery of ecosystem services. Conducting a planting risk analysis can help avoid failure of restoration strategies involving simultaneous planting of early-, mid-, and late-successional tree species. This in turn will improve cost-effectiveness of initial interventions in large-scale, long-term restoration programs.
Examining local awareness and perceptions of illegal resource harvesting is a difficult but necessary part of designing efficient wildlife resources conservation programs. We examined awareness and attitudes related to wildlife hunting practices among local communities in the Magu, Bunda and Serengeti districts in the western part of Serengeti National Park, Tanzania. We also examined the influences of socio-demographic variables on awareness of hunting and some of the methodological challenges linked to researching sensitive resource topics. Members of these communities were fairly aware of the occurrence of illegal hunting practices, as well as the modalities of existing law enforcement, but knowledge about legal hunting systems was limited. The extent of awareness of these practices and attitudes towards them were significantly affected by age, gender, and level of education, with limited awareness observed among women and those with higher education levels. Observed challenges were mostly related to respondents' attitudes and sensitivity to illegal wildlife uses, including fear to disclose information and non-responses to specific questions. The relatively extensive awareness of illegal hunting practices probably reflects community members' involvement in illegal wildlife use. Improved education programs are needed as well as provision of alternative livelihood opportunities that may decrease dependence on wildlife resources.
Using the distributional information from approximately 22,000 georeferenced records of the 53 currently recognized species of the genus Eurysternus Dalman, 1824, we explore the main macroclimatic determinants capable of explaining the distribution of these species. We also estimate the potential distribution of these species using a previously established protocol. Our results show that annual mean temperature and annual precipitation are the variables with the greatest explanatory capacity. Our results also show that species with wide climatic niches would primarily inhabit the rainiest and coldest American locations. The potential species-richness map derived from the overlap of individual potential distributions has allowed us to identify suitable areas that are not yet adequately surveyed. Future investigations must be conducted in these areas to improve the biogeographical and taxonomic knowledge of this genus.
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