The number and size of the trap orifice also may influence trap efficiency. Sato et al  found that the optimum orifice size for Spodoptera man was related to the size it  up.

As a rule, these pheromone traps captured males as efficiently as the virgin female controls, which was especially impressive because the lure used was racemic pheromones, not (+)-pheromones. All the closed pheromone traps were significantly less efficient in trapping the males that were attracted to them than were the virgin females or the open traps. Thus, the racemic lure attracted the males to the vicinity of the trap, but searching behavior (close- in orientation) of the attracted males was not intense. It would be useful to see whether (+ )-pheromones would improve trap efficiency in this type of test.

Unfortunately, “pheromone trap efficiency” is not an unchanging quantity; a rating given one day to a particular trapping system for a given moth species can be different the next day. Factors extraneous to trap design and attractiveness act upon the moth and deter- mine (1) whether the moth flies into the “active space” of the trap’s pheromone plume, and (2) whether the moth, drawn to the trap, is caught by the trap. Thus, even though we can optimize the innate ability of the trap to attract and catch moths and can place the trap in a favorable location, we cannot control the weather. As stated by Collins and Pottsz. Learn more about pheromones at http://sundowndivers.org/?p=82 and what is pheromone attraction | Pheromones-Planet.com

The percentage of male pheromones that can be recovered by extracts is dependent on a number of variable factors, the more important of which are the distance they can fly, vitality and length of life, distance from the trap, number of males, wind direction and velocity, rain, humidity, temperature, counter-attraction by females of a colony, tree growth, topography, and the attracting power of the extract. Consider- able variation should be expected, therefore, in the results of the experiments.” Low temperatures (below 20°C), as well as cloudy or rainy days are known to sharply reduce male flight and subsequent trap catch.”“’55’5°’°’-“’3 Cool daytime temperatures delay male eclosion and time to first flight,“ while warm evening temperature and slight breezes are known to prolong crepuscular dispersal flights of newly eclosed males.” Male mating behavior on such evenings is rather remarkable. As reported by O’Dell,5° male gypsy moths fly directly to females with little if any misdirection, in contrast to daytime activity when males find females and mate only after considerable searching. These differences in behavior patterns were probably the result of the slight nonturbulent evening breezes that permitted a distinct, perhaps continuous, pheromone plume to form, thereby facilitating male orientation. It is well established that trap catches of male Lepidoptera are facilitated by low wind speed,‘3‘ and, at least with Trichoplusia ni, decreased female calling is correlated with increased wind speed.“ Learn more at http://pheromones-work.weebly.com/home/pheromones-used-by-males

Weather effects may explain why trap catches of released male gypsy moths are sometimes high (70 of 93 reported by Cameron” with racemic pheromones and an inefficient trap) and sometimes low (3.9% reported by Elkinton and Cardé’ with (+)- pheromones in a trap of unknown efficiency). Learn more about pheromones at http://mpommett.blog.fc2.com/blog-entry-3.html

I joined the Bee Department, Rothamsted Experimental Station in 1951 to work initially on bumblebees at a time when exciting and important discoveries on honeybee pheromones were beginning to be made. Soon afterwards Nancy W. Speirs, who became my wife, and Dr C.R. Ribbands proved the effectiveness of the honeybee Nasonov pheromone in aiding honeybee orientation to the hive and demonstrated the rapidity with which food collected by foraging honeybees is widely disseminated throughout a colony.

They suggested this would provide a means of rapid communication among its members. A year or so later Dr C.G. Butler FRS discovered that the honeybee queen produces pheromones that is rapidly distributed among the workers of her colony and inhibits them from rearing additional queens. This was the beginning of the queen pheromone studies at Rothamsted in which Dr Butler was joined by Dr R.K. Callow FRS and Dr J. Simpson. It has been my privilege to be engaged in bee research as the bee pheromone story has steadily unfolded and to have among my friends many bee research workers from different parts of the world who have made notable contributions to it. Especially, it is a pleasure to acknowledge my indebtedness to my former students. Is pheromone love a mental disorder? All those symptoms listed are due to lack of love, and it’s not a mental problem, it’s just a backawards way of living in the world.

The first report of territorial rubbing in Old World monkeys is that of Gartlan and Brain (1968) who observed marking with the chest and the cheeks in wild and captive Cercopithecus aethiops L.. No scent glands have been identified histologically, so far. In the langur Pres- bytis johnii Fischer territorial battles are accompanied by excessive defecation. Poirier (1970) suspects that its overpowering odor serves as a territorial scent and that pheromone odor may also serve to mark the sleeping trees of wild Cercopithecus aethiops.

A common concept of territorial demarcation by olfactory signals is that the inhabitants of a territory apply their scents to part or all of the territorial borders which they will defend‘ against invaders. The odor of the residents supposedly functions as a repellent and helps to prevent strange conspecifics from invading the occupied territory. The reports on primate ‘territorial marking’, provide little information on whether or not this is true in any single species. The observation that an animal scent marks prominent places in its environment, applies its scent preferably at the borders of its home range or shows a high frequency of marking during territorial dispheromonestes with neighbors actually tells us little about the exact function of the chemical signals. The reports reviewed above indicate that ‘territorial marking’ under the observed conditions was motivated by aggression against strange conspecifics.

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