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Illegal hunting (poaching) is a global threat to wildlife. Anti-poaching initiatives are making increasing use of technology, such as infrared thermography (IRT), to support traditional foot and vehicle patrols. To date, the effectiveness of IRT for poacher location has not been tested under field conditions, where thermal signatures are often complex. Here, we test the hypothesis that IRT will increase the distance over which a poacher hiding in African scrub bushveldt can be detected relative to a conventional flashlight. We also test whether any increase in effectiveness is related to the cost and complexity of the equipment by comparing comparatively expensive (22000 USD) and relatively inexpensive (2000 USD) IRT devices. To test these hypotheses we employ a controlled, fully randomised, double-blind procedure to find a poacher in nocturnal field conditions in African bushveldt. Each of our 27 volunteer observers walked three times along a pathway using one detection technology on each pass in randomised order. They searched a prescribed search area of bushveldt within which the target was hiding. Hiding locations were pre-determined, randomised, and changed with each pass. Distances of first detection and positive detection were noted. All technologies could be used to detect the target. Average first detection distance for flashlight was 37.3m, improving by 19.8m to 57.1m using LIRT and by a further 11.2m to 68.3m using HIRT. Although detection distances were significantly greater for both IRTs compared to flashlight, there was no significant difference between LIRT and HIRT. False detection rates were low and there was no significant association between technology and accuracy of detection. Although IRT technology should ideally be tested in the specific environment intended before significant investment is made, we conclude that IRT technology is promising for anti-poaching patrols and that for this purpose low cost IRT units are as effective as units ten times more expensive.

Electrophysiological techniques were used to obtain recordings of extracellular electrical activity from the anterior end of live adult females of Brugia pahangi. Stimulation with 100 mM, 10 mM and 1 mM acetylcholine resulted in an increase in spike activity which was concentration dependent, whereas stimulation with phosphate-buffered saline and 0.1 mM acetylcholine gave no increase in activity. The delay in response was not concentration dependent. The action of possible host cues was investigated. Stimulation with heat-inactivated foetal calf serum (IFCS) and 10 mM glutathione gave an increase in spike activity but exposure to 5 mg/dl haemoglobin elicited no response. The response to IFCS was found to be suppressed completely by pre-incubation for 30 min in ivermectin.

Electrophysiological techniques were developed to obtain recordings of electrical activity from the anterior end of live, second stage juveniles (J2) of Globodera rostochiensis. Sequential exposure of individual J2 to test semiochemicals was also possible using a modified perfusion system. Concentration-dependent responses were obtained from J2 during exposure to 0.1, 1, 10 and 100 mM acetylcholine. The delay before any response was not concentration-dependent. The responses to 10 mM concentrations of several chemicals known to elicit a feeding response in insects were assessed. There was a significant increase in spike activity when J2 were exposed to D-tryptophan but glycine and citric acid elicited no responses. Exposure to D-glutamic acid resulted in a significant increase in spike activity but exposure to the L-isomer gave no response. This was confirmed by sequential exposure of J2 to the L- then to the D-isomer. Exposure to potato root diffusate elicited a response, whereas a non-host root diffusate from sugar beet and female secretory-excretory (S-E) product caused no change in activity. Die Analyse chemosensorischer Reaktionen von Juvenilen des zweiten Stadiums von Globodera rostochiensis mit elektrophysiologischen Techniken - Zur Gewinnung von Informationen über die elektrische Aktivität des Vorderendes von Juvenilen des zweiten Stadiums (J2) von Globodera rostochiensis wurden elektrophysiologische Untersuchungsmethoden entwickelt. Aufeinander folgende Behandlungen einzelner J2 zur Prüfung von Semiochemikalien wurden auch durch ein verändertes Perfusionssystem erreicht. Bei der Behandlung von J2 mit 0.1, 1, 10 und 100 mM Acetylcholin wurden konzentrationsabhängige Reaktionen erzielt. Die Verzögerung vor dem Sichtbarwerden einer Reaktion war dagegen nicht konzentrationsabhängig. Es wurden auch die Reaktionen auf 10 mM Konzentrationen mehrerer Substanzen geprüft, die bei Insekten eine Nahrungsaufnahme auslösen. Bei D-Tryptophan trat eine deutliche Erhöhung der Spitzenaktivität ein, bei Glycin und Zitronensäure erfolgte keine Reaktion. Eine Behandlung mit DGlutaminsäure erhöhte die Spitzenaktivität deutlich, nicht jedoch das L-Isomer. Diese Beobachtung wurde bestätigt, wenn man die J2 erst dem L- und anschließend dem D-Isomer aussetzte. Die Behandlung mit Kartoffelwurzel-Ablaufwasser rief eine Reaktion hervor, nicht aber Wurzelextrakte des Nichtwirtes Zuckerrübe und Produkte des sekretorisch-exkretorischen Systems von Weibchen.