Testing Global Positioning System Performance for Wildlife Monitoring Using Mobile Collars and Known Reference Points

Abstract: To determine the spatial resolution of Global Positioning System (GPS) receiver data, rigorous testing is essential. We tested performance of the Lotek 3300 GPS collar for medium-sized mammals (Lotek Engineering, Inc., Newmarket, ON, Canada). To mimic real wildlife monitoring situations, we performed both static (stationary receiver) and mobile tests, placing the receiver collar on a dog. We compared fix locations of the mobile receiver with the actual trajectory described by a portable Trimble high-precision GPS. We determined performance in relation to habitat type and leaf cover. Location error was habitat-dependent, with the best results in open habitat and much poorer ones in forest, particularly coniferous-dominated forest. For both static and mobile tests, location accuracy was higher when the number of satellites contacted was high and when the residual positional dilution of precision (PDOP) value was low. However, location error was highly variable, even for a given PDOP value and a given number of satellites contacted. Finally, mobile collars performed less well than their static counterparts, presumably because of frequent changes of GPS position and orientation.     

BACILLUS CEREUS PATHOGENICITY: A REVIEW

Pathogenic Bacillus cereus can be routinely isolated and identified in the laboratory from foods and other sources. Typing of B. cereus strains implicated in food poisoning outbreaks is helpful for confirmation of the origin of the outbreak and for epidemiological studies. Data concerning vegetative growth and spores are given. Different types of toxin are produced by B. cereus in the course of its growth: a so-called diarrheal enterotoxin and an emetic heat-stable toxin; their biochemical characteristics and the systems used for their detection are reviewed. Different types of hemolysins and phospholipases C are also produced and may play a role in pathogenicity. Nongastrointestinal infections were also traced to this species.     

The Politics of Tradition: Toward a Generic Culture in Vanuatu

The paper examines the role of the elite in generating constructions of tradition in present-day Vanuatu. While stopping short of postulating a ‘conspiracy theory’ interpretation, the paper does argue that the proto-bureaucratic 'class' is attempting to gain control over a symbolic code derived from traditional practices (kastom) so as to promote social cohesion and establish a civil polity. The negative case of kava, a symbol of traditional culture which was significantly not included in this corpus is discussed at length.     

Field experiments on the relationship between drift and henthic densities of aquatic insects in tropical streams (Ivory Coast). III Trichoptera

SUMMARY. 1. Based on in situ gutter trials we related the drift of caddis flies to their benthic densities and to various abiotic factors in streams in the Ivory Coast (West Africa). Members of the families Hydropsychidae, Philopotamidae. Hydroptilidae and Leptoceridae were considered in detail.
2. The drift of larvae peaked at night in both early and late larval instars.
3. Drift of a larval group (a certain instar, species or higher taxon) was more often related to the benthic density of other larval groups than to its own benthic density.
4. Self-regulation of an upper benthic density of a larval group by emigration through drift was not statistically evident.
5. There was no straightforward relationship between drift and abiotic factors.
6. Drift rates differed between taxa as well as between larval instars (size groups) within a taxon. Newly hatched larvae had very high drift rates, whereas the last larval instar usually had the lowest drift rate.
7. We related these results to the violently fluctuating discharge of the streams in the study area and the consequent variability of space for lotic insects.
8. Drift estimates, made at the same time as a monitoring programme on possible side-effects of insecticides (Onchocerciasis Control Programme), failed to reflect benthic densities except in the night drift of Hydropsychidae.     

Phylogeography of spiny mice (genus Acomys, Rodentia: Muridae) from the south-western margin of the Sahara with taxonomic implications

The present study aims to depict the overall pattern of Acomys history in south-western Sahara. We tested the specific predictions that: (1) several mitochondrial clades can be identified and that they coincide with the described species; (2) successive phases of desert expansion and contraction during the last 3 Myr have resulted in several phases of demographic expansion and population fragmentation in Acomys ; and (3) isolation-by-distance occurs. The extent of phylogeographic patterns and molecular genetic diversity (cytochrome b gene and D-loop) were addressed in a survey of 90 individuals of Acomys from 38 localities. Our phylogeographical analyses show a strong genetic structure within western Saharan Acomys , with several phylogroups displaying non-overlapping geographic distributions. Restricted gene flow with isolation-by-distance was recorded and a signal of population expansion was detected within several clades. We suggest that during arid or semi-arid paleoclimatic periods, when large sandy areas were present, Acomys was restricted to rocky massifs, whereas, in more humid periods, when savannah and/or steppe habitat prevailed, this species was able to disperse and to survive outside rocky areas because food resources were abundant. Based on a comprehensive sampling and the use of an integrative approach (i.e. combining cytogenetic, molecular and morphological data), we firmly propose that Acomys airensis should be considered as a junior synonym of Acomys chudeaui .  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 98 , 29–46.     

Foraging, home range use and social behaviour of a group-living rainforest raptor, the Red-throated Caracara Daptrius americanus

A stable group of six Red-throated Caracaras Daptrius americanus was followed over 5 years in a rainforest area of French Guiana and was intensively studied during 52 days in 1989-90. They bred successfully only twice (1986 and 1990). Communal nest guarding and brood care were observed. Their social behaviour and group-living habits seem unique among raptors. The 400-ha all-purpose, year-round, group territory was defended by all individuals and was almost fully used. The birds foraged individually, but the cohesion of the group and its coordinated movements were maintained by periodic loud rallying calls. Food sharing of large prey items and even deliberate allofeeding also contributed to the group cohesion. Mature, high, closed-canopy forest was preferred and 88% of the actively foraging birds were encountered in the understorey, where they had a higher success rate than those hunting in the upper canopy. This may explain why the species' frequency and group size markedly decreased in secondary or disturbed forests. The 12-hour daily activity period was reduced by an average of 2 hours either by a midday pause (hot weather) or by rains. At least 74% of all food items taken were wasp nests or other insect nests in the foliage, 9% were hard fruits, and the remaining captures were various invertebrates or unidentified items. When the caracaras were raiding a wasp nest, the wasps were kept off probably by a powerful repellent, a striking adaptation unprecedented among birds. Several species of mostly large canopy frugivores regularly formed close associations with the caracaras to forage in the understorey, where they otherwise rarely or never ventured. This new interspecific flocking behaviour is interpreted as an antipredator strategy benefiting from the raptors' warning and mobbing efficiency.