Night Capture of Roosting Cave Birds by Neanderthals: An Actualistic Approach

Evidence is accumulating on the regular and systematic Neanderthal exploitation of birds. However, the motivations, mechanisms, and circumstances underlying this behavior remains little explored despite their potential implications on Neanderthal ecology and capabilities. Fossil remains of choughs (Pyrrhocorax, Corvidae) are among the most abundant in cave sites with Mousterian technology. We reviewed the evidence showing that Neanderthals processed choughs for food, and confirmed that it occurred frequently over a widespread spatial and temporal scale. This lead us to propose the hypothesis that the cave-like refuge is the keystone resource connecting Neanderthals and choughs captured at night in rocky shelters eventually used by both species. By adopting an actualistic approach, we documented the patterns of refuge use and population dynamics of communally roosting choughs, the strategies and technology currently used to capture them, and their behavioral response against experimental human predators at night. Actualistic experiments showed that large numbers of choughs can be captured without highly sophisticated tools at night regularly and periodically, due to their occupation year-round during long-term periods of the same nocturnal shelters, the constant turnover of individuals, and their high site tenacity at these roost-sites even after recurrent disturbance and predation. Captures even with bare hands are further facilitated because choughs tend to flee confused into the cavity in darkness when dazzled and cornered by human (experimental) predators. Given the extreme difficulty of daylight chough capturing in open country, nocturnal hunting with the help of fire in the roosting caves and consumption in situ are proposed as the most plausible explanations for the strong association of choughs and Neanderthals in fossil assemblages. Night hunting of birds has implications for the social, anatomical, technological, and cognitive capacities of Neanderthals.

A study on diversity and distribution of Ficus L. (Dicotyledonae: Moraceae) species at Forest Research Institute (FRI), Dehradun (Uttarakhand), India

Ficus L., commonly known as Fig, is a member of the family Moraceae (mulberry family) comprises 37 genera and approximately 1,100 species distributed in diverse ecosystems, especially in tropical and temperate regions of the world. The Ficus genus stands out as a keystone resource provider in many tropical forests, which is probably because of continuous non-seasonal fruiting in many species. It is one of the largest genera in the angiosperms about 750 species. The present study was carried out in the Forest Research Institute (FRI) campus, Dehradun (Uttarakhand), India. The phytodiversity of Ficus L. and their socio-economic values worked out during the investigation, religious-spiritual attachment, food of wild animals, ethnomedicinal and timber significance. There were 16 species of Ficus L. recorded from New Forest, FRI, Dehradun based on the morphological observations of taxonomically significant characteristics. The species found in FRI New Forest Dehradun were, Ficus benjamina, F. religiosa, F. racemosa, F. rumphii, F. retusa, F. krishnae, F. elastica, F. virens, F. semicordata, F. auriculata, F. hispida, F. pumila, F. palmata, F. drupacea, F. benghalensis, F. pomifera. Out of the notified 16 species of Ficus, 11 species were trees, 3 shrubs and 2 climbers in nature. The maximum leaf size (30×27cm2) was reported in F. auriculata, followed by F. semicordata (28×10cm2), F. benghalensis (25×11cm2). However, minimum leaf size was noticed in F. benjamina (4×2cm2) and F. retusa (4×3cm2). Among, 15 species, axillary fig (fruit) arrangement was observed, while one species (F. racemosa) has stem position of fruits. The current finding is itself a pioneer study to present a glimpse of such immense species diversity of single genera from sub-valley areas and will be a milestone for future studies in conservation and management of these wild varieties.

Characteristics of General Soils, Natural Saltlicks and Artificial Saltlicks for Wild Asian Elephants (Elephas Maximus) Conservation in the Western Forests of Thailand

Saltlicks are a keystone resource of wildlife. This study aimed to compare the characteristics among general soil, natural saltlicks and artificial saltlicks in the natural forest of Salakphra Wildlife Sanctuary (SWS) and restoration habitat for elephant (Elephas maximus) in Kui Buri National Park (KNP), western Thailand. Twenty general soils, 33 natural and 35 artificial saltlicks were analyzed. The chemical compositions in natural saltlicks were not consistent. The K, Mg, Fe and Cu in natural saltlicks were higher than artificial saltlicks in both areas. The Ca and Zn in artificial saltlicks in SES were higher than natural saltlicks of KNP. The salinity in artificial saltlicks was highest and higher than in natural saltlicks in both areas and can provide supplemental Na, thereby increasing salinity in both areas. The artificial saltlicks cannot provide Ca, K, Mg, Fe and Cu when compared to natural saltlicks that can provide a primary target for elephants at these sites. The findings have consequences for conservation of elephants and other large herbivores by supplementing essential macro- and micro-nutrients in artificial saltlicks. The key resources can provide information to help maintain the wildlife health and fecundity of the region.

Nocturnal scent in a ‘bird-fig’: a cue to attract bats as additional dispersers?

The plant genus Ficus is a keystone resource in tropical ecoystems. One of the unique features of figs is the diversity of fruit traits, which in many cases match their various dispersers, the so-called fruit syndromes. The classic example of this is the strong phenotypic differences found between figs with bat and bird dispersers (color, size, and presentation). The ‘bird-fig’ Ficus colubrinae represents an exception to this trend since it attracts the small frugivorous bat species Ectophylla alba at night, but during the day attracts bird visitors. Here we investigate the mechanism by which this ‘bird-fig’ attracts bats despite its fruit traits, which should appeal solely to birds. We performed feeding experiments with Ectophylla alba to assess the role of fruit scent in the detection of ripe fruits. Ectophylla alba was capable of finding ripe figs by scent alone under exclusion of other sensory cues. This suggests that scent is the main foraging cue for Ectophylla alba. Analyses of odor bouquets from the bat- and bird-dispersal phases (i.e. day and night) differed significantly in their composition of volatiles. The combination of these two findings raises the question whether E. alba and F. colubrinae resemble a co-adaptation that enables a phenotypically classic ‘bird-fig’ to attract bat dispersers by an olfactory signal at night thus maximizing dispersal.

Environmental DNA for the enumeration and management of Pacific salmon

Pacific salmon are a keystone resource in Alaska, generating annual revenues of well over ∼US$500 million/yr. Due to their anadromous life history, adult spawners distribute amongst thousands of streams, posing a huge management challenge. Currently, spawners are enumerated at just a few streams because of reliance on human counters and, rarely, sonar. The ability to detect organisms by shed tissue (environmental DNA, eDNA) promises a more efficient counting method. However, although eDNA correlates generally with local fish abundances, we do not know if eDNA can accurately enumerate salmon. Here we show that daily, and near-daily, flow-corrected eDNA rate closely tracks daily numbers of returning sockeye and coho spawners and outmigrating sockeye smolts. eDNA thus promises accurate and efficient enumeration, but to deliver the most robust numbers will need higher-resolution stream-flow data, at-least-daily sampling, and a focus on species with simple life histories, since shedding rate varies amongst jacks, juveniles, and adults.

Phenology, abundance and consumers of figs (Ficus spp.) in a tropical cloud forest: evaluation of a potential keystone resource

Fig trees (Ficus spp) produce fruit year-round and figs are consumed by a large proportion of frugivores throughout the tropics. Figs are potential keystone resources that sustain frugivore communities during periods of scarcity, but studies have produced contradictory results. Over 1 y we monitored the phenology of 206 trees of five Ficus species in a Colombian cloud forest, to test whether figs produced fruit during periods of low overall fruit availability. We also measured fig tree densities in 18 0.5-ha plots and made 190 h of observations at 24 trees of three species to determine whether figs were abundant and consumed by a large proportion of the local frugivores. The five species produced fruit year-round but fig availability varied monthly by orders of magnitude. Fig trees reached comparatively high densities of 1–5 trees ha−1 and were consumed by 36 bird species (60% of the local frugivore assemblage) and three mammal species. However, there was no season of fruit scarcity and figs represented on average 1.5% of the monthly fruit biomass. Figs in this Andean forest are part of a broad array of fruiting species and at least during our study did not seem to constitute a keystone resource.