Metabarcoding of vertebrate DNA derived from carrion flies has been proposed as a promising tool for biodiversity monitoring. To evaluate its efficacy, we conducted metabarcoding surveys of carrion flies on Barro Colorado Island (BCI), Panama, which has a well-known mammal community, and compared our results against diurnal transect counts and camera trapping. We collected 1,084 flies in 29 sampling days, conducted metabarcoding with mammal-specific (16S) and vertebrate-specific (12S) primers, and sequenced amplicons on Illumina MiSeq. For taxonomic assignment, we compared blast with the new program protax, and we found that protax improved species identifications. We detected 20 mammal, four bird, and one lizard species from carrion fly metabarcoding, all but one of which are known from BCI. Fly metabarcoding detected more mammal species than concurrent transect counts (29 sampling days, 13 species) and concurrent camera trapping (84 sampling days, 17 species), and detected 67% of the number of mammal species documented by 8 years of transect counts and camera trapping combined, although fly metabarcoding missed several abundant species. This study demonstrates that carrion fly metabarcoding is a powerful tool for mammal biodiversity surveys and has the potential to detect a broader range of species than more commonly used methods.

Abstract

No abstract

We collected details on the predation of four agoutis (Dasyprocta punctata) by ocelots (Leopardus pardalis). All kills were made outside of the typical agouti activity period (<0500 h). Agoutis were captured from behind and killed with a bite through the back of the skull. The kill sites for two female agoutis were significantly closer to their den sites than expected, while kill sites for two males were not. All carcasses were completely covered by leaves during the day and were fed on during night hours. Predation by ocelots can be a significant cause of mortality for agoutis at Barro Colorado Island (BCI). RESUMENColectamos detalles en la depredación de 4 agoutis (Dasyprocta punctata) por ocelotes (Leopardus pardalis). Todas las depredaciones fueron fuera del periodo típico de actividad (<0500 h). Los agoutis fueron capturados por detrás y muertos con una mordida en la parte trasera del cráneo. Los lugares de muerte en las dos hembras fueron significativamente cerca de sus guaridas, mientras que los machos no. Los cadáveres fueron completamente cubiertos con hojarasca durante el día y fueron consumidos solamente durante la noche. La depredación por ocelotes puede ser una causa significativa de mortalidad de los agoutis en BCI.

Estimates of population density are essential for the effective conservation and management of any threatened species. Accurately estimating density of elusive carnivores can be a challenge, however. One approach to this challenge is integration of DNA collected noninvasively from feces with capture-recapture modeling. To date, the bias and precision of this technique have seldom been evaluated in the field. We compared density estimates of ocelots (Leopardus pardalis) derived from fecal noninvasive genetic techniques to density estimates from camera trapping in the same population, during the same study period. Density estimates from the two techniques were comparable, especially when using spatially explicit capture-recapture models. Population density estimated using the program DENSITY was 1.74/km 2 (SE = 0.584) from noninvasive genetics and 1.59/km 2 (SE = 0.464) from camera trapping. These estimates also represent the highest reported ocelot population density within the species range.

No abstract

a b s t r a c tIn solitary carnivores, scent marking is an important form of communication among individuals. We examined the extent of potential communication among ocelots (Leopardus pardalis) at communal latrine sites at the population level. We used a combination of camera-trapping and noninvasive genetics to monitor 18 ocelot latrines in an isolated population on Barro Colorado Island in the Republic of Panama. We found that 72% of monitored ocelot latrines were used by multiple individuals of both sexes, with a mean of 3.0 individuals (range 1-9) per year using each latrine. One highly used latrine was visited by 17 different individuals including 11 males and 6 females over the course of 6 years. Based on visits to the same latrine within 10 days of one another, potential for scent communication among individuals was high. Males had the potential to communicate with a mean of 5.9 other individuals (range 2-14), and females had the potential to communicate with a mean of 4.5 other individuals (range 3-12) at latrines. We conclude that communal latrines are important centers of scent communication for Leopardus pardalis.

Though the harmful effects anthropogenic disturbances pose to wild primates are well appreciated, comparatively little is known about the effects of natural disturbances. From December 2010 to January 2011, different mortality patterns were observed for two primate species, capuchins and howler monkeys, on Barro Colorado Island (BCI), Panama. Unusually high rainfall in 2010 was associated with census and cadaver data indicating the rapid loss of >70% of the capuchin population in late 2010 to early 2011. In contrast, over this same period, no decline was documented for howler monkeys and cadaver data for howlers was unexceptional. The high mortality experienced by the capuchin population was unexpected and its extent was not fully appreciated until the event was largely over. Explanations proposed for it included effects of hypothermia, disease or a shortage of some essential nutrient(s). Of these, the dietary explanation seems most probable. BCI capuchins depend most heavily on arthropod foods in December, when few higher quality ripe fruits are available. The unprecedented high rainfall in December 2010 is hypothesized to have largely eliminated the arthropod peak expected on BCI each December. A lack of protein-rich arthropods, when coupled with the climatic and nutritional stress capuchins generally experience at this time of year, appears to have precipitated the rapid die-off of most of the island's capuchin population. As howler monkeys obtain dietary protein primarily from leaves, a shortage of edible arthropods would not affect howler numbers. Comparison of our 2010 data with similar data on earlier primate/mammalian mortality events reported for BCI and for Corcovado, Costa Rica indicates that our understanding of the effects of natural disturbances on wild primate populations is not profound. We suggest that more research be devoted to this increasingly timely topic, so important to conservation policy.