Total capture efforts totalized 6,033 trap/nights, 136 mist-net/nights and 108 cameras/nights.
We used several methods of record for the different mammal groups including 1) capture techniques with mist nets, snap traps, Sherman traps, Tomahawk traps and pitfall traps, 2) and detection techniques direct by means of camera traps, visualization of mammals during long walk, observation of tracks and interviews to local people. Therefore we surveyed mammals in three habitat types of the Pampas del Heath (savanna, ecotonal area and forest) during late 2011. Many endangered species and/or endemic from savannas occur there, however studies about the diversity of mammals in Pampas del Heath are limited and only three assessments there have been carried out since mid-1970s. These results are discussed in the context of moonlight as a cue of predation risk, as well as the hypothesized antipredator adaptations of bipedal rodents.īahuaja Sonene National Park protects the unique sample of subtropical humid savannas in Peru, which are known as “Pampas del Heath” with 6,136 hectares of area. Thus, moonlight avoidance may be an over-generalized phenomenon that actually occurs only in certain species and under specific circumstances. Moreover, bipedal rodents are only found to avoid moonlight during the summer season, and not during the spring and fall seasons. A further analysis during waxing moon phases indicates that quadrupedal rodents may in fact increase their activity on the same brightly moonlit periods avoided by bipedal rodents. Bipedal and quadrupedal rodent guilds within the rodent community are found to respond dissimilarly to moonlight only bipedal rodents, but not quadrupedal rodents, display significant moonlight avoidance overall and during waxing moon phases.
However, significant moonlight avoidance is revealed throughout the rodent community when nights of trapping around the new moon are removed from the analysis. No relationship is found overall between the total abundance of the rodent community and moonlight. The activity patterns of this desert rodent community are assessed on 69 nights with clear skies (10,758 total trapnights) and examined in relation to corresponding values of moon phase and moon brightness to assess the frequency of moonlight avoidance. Rodent activity is examined by live-trapping exclusively in sandy and open habitats throughout the Great Basin, using the presence of the sand-obligate kangaroo mouse (Microdipodops) as a habitat-indicator taxon. Here, a study in natural habitats was performed where the effects of moonlight on the activity patterns of desert rodents are examined in 62 separate localities across the Great Basin Desert of western North America from 1999 to 2006. Moonlight avoidance behaviors have been observed in many nocturnal rodents and are widely generalized to small mammals, but in no previous study has moonlight avoidance been evaluated in a systematic fashion in a naturally occurring community over several seasons. To identify variations in the risk of predation, nocturnal rodents may use moonlight as an indirect cue of risk. Moonlight, on the other hand, cannot provide the bright light plants need.Rodents make foraging decisions by balancing energetic and reproductive demands with predator avoidance. Sunlight is a key factor for the nutrition and growth of plants. Regions that receive direct sunlight during the day can reach 130,000 lux. At night, the moonlight illuminates the earth in the range of 0.05-0.1 lux. Sunlight is hundreds of thousands of times brighter than moonlight. If the surface of the Moon were brighter or larger, it could reflect more light. Therefore, the moon reflects enough light to appear bright. On the other hand, the moon has a very large volume and a great amount of light falls on all this massive mass. The surface of the Moon is not as reflective as a mirror or as ice. Moonlight is sunlight reflected from the dark gray surface of the Moon. When you go out on a sunny day, when you see dark gray rocks illuminated by direct sunlight, you are looking at something that looks like moonlight. Now the light hitting the wall is like sunlight. Move the mirror away and point the flashlight directly to the wall. This light hitting surfaces is like moonlight. You will see that the light reflected from the mirror is reflected on the floor, ceiling or wall. Take a mirror in your hand and point the flashlight towards the mirror at an appropriate angle.
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