Factors Affecting Adult Captures of the Cotton Bollworm, Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) in Pheromone-Baited Traps

The effects of funnel-trap color, trap height and pheromone formulation on the adult captures of the cotton bollworm, Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) were evaluated in traps that were suspended in cotton fields in central Greece. Briefly, in a first trial, the efficacy of funnel traps of three different colors, i.e., green, striped (with black and white stripes) and white, was comparatively evaluated, whereas in a second trial green funnel traps were placed at three heights, i.e., 30, 60 and 90 cm from the ground. Finally, in a third trial we tested the efficiency of green funnel traps with three commercially available pheromone lures. Considering the overall captures, trap color and pheromone formulation affected male captures, whereas trap height had no influence. Captures notably increased in all traps from late August to mid-September. In total, the white funnel trap captured more moths than the green or striped funnel traps. Placement of the traps at different heights did not significantly affect captures, but seasonal differences were observed at individual dates during the trapping period. Barrettine’s pheromone lure provided significantly more captures than the other two (Russell, Trécé) in some of the trap-check dates. The results can be further utilized in the monitoring protocols of H. armigera in cotton fields.

An Assessment of the Efficacy of Pheromone Traps in Managing the Red Palm Weevil

This experiment was performed in date palm farms to assess the effectiveness of a newly designed pheromone trap (i.e., funnel trap) in capturing red palm weevil (RPW) adults and to compare it to traditional traps. The number of captured RPWs varied by month, with a total of 3931 adults captured during the experiment. Analysis of variance demonstrated significant differences in the number of captures between the three traps. The funnel traps captured 1627 RPW adults in total, while the buried and burlap bucket traps captured 1079 and 1225 weevils, respectively. The mean (± SE) number of captures/trap/weeks was 2.62 ± 0.11 in funnel traps, which was significantly higher than that of buried bucket traps (1.73 ± 0.06) and burlap bucket traps (1.97 ± 0.07). Both sexes were attracted to traps; however, the number of female weevils captured was significantly higher than that of males with a sex ratio (female/male) of 1.58 ± 0.03. According to the findings, the pheromone-food-bait funnel trap is a promising solution for reducing RPW populations and thus protecting date palm trees from infestations.

Evaluation of the ambrosia beetles traps on Pterocarpus indicus in Indonesia

Tarno H, Setiawan Y, Rahardjo BT, Wang J. 2021. Evaluation of the ambrosia beetles traps on Pterocarpus indicus in Indonesia. Biodiversitas 22: 1332-1339. Angsana, Pterocarpus indicus Willd., is a native tree of Southeast Asia. This tree is commonly planted in large numbers as an ornamental or shade plant along the roads, in parks, and in residential areas in Malang and Batu Cities of Indonesia. Ambrosia beetles Euplatypus parallelus (F.) and Treptoplatypus micrurus (Schedl.) have been reported to attack P. indicus trees in Malang and Batu Cities. Therefore, effective traps are required for early detection and monitoring of the spread of ambrosia beetles. This research aimed to evaluate the effectiveness of different traps and to investigate the diversity of ambrosia beetles on P. indicus trees in Malang and Batu Cities. This research was conducted along the roads in Malang and Batu Cities using four types of traps: funnel trap, window flight trap, bottle trap, and yellow sticky trap. Eleven ambrosia beetle species were collected in this research. The most abundant species were E. parallelus and Cryphalus laticollis (Browne). The funnel trap was the most effective for capturing ambrosia beetles, whereas the bottle trap was the least effective trap. The funnel trap captured more E. parallelus and C. laticollis individuals than other traps. The ambrosia beetles captured using different traps were categorized as having low diversity. The ambrosia beetles collected from Malang and Batu Cities were categorized as having moderate diversity.

Evaluating Efficiency of Different Sampling Methods for Arboreal Ants (Hymenoptera: Formicidae) in A West African Forest-Savanna Mosaic

Ants constitute an important part of arboreal arthropod biomass in rainforests. Nevertheless, there are only a few methods which permit a rapid assessment of these insects in the canopy layer. This study aims at evaluating the efficiency of a new variant type of pitfall trap i.e. “the funnel trap”, to sample arboreal ants in a secondary and gallery forest in Lamto reserve (Côte d’Ivoire). This method was compared to standard arboreal pitfall trap and beating. In total, the 3 methods yielded 7072 ant workers belonging to 43 species, 14 genera and 5 subfamilies. Tree beating recorded the highest ant’s numerical abundance (3670 workers), with 27 species, 12 genera and 3 subfamilies followed by the “funnel trap” that yielded 2800 ant workers, with 23 species belonging to 12 genera and 5 subfamilies. Finally, arboreal pitfall traps caught the lowest individual with 602 ant workers from 20 species belonging to 9 genera and 3 subfamilies. The composition of species which are caught by arboreal pitfall trap and “funnel trap” was similar at 53 percent. Tree beating showed a distinct species composition compared to arboreal pitfall trap and “funnel trap”. The “funnel trap” could be a fast and efficient way to quickly assess ant-biodiversity in forest canopies and agroecosystems as it looks like a non-destructive sampling method.

A simple standardized protocol to evaluate the reliability of seed rain estimates

Seed dispersal has key implications for community dynamics and restoration ecology. However, estimating seed rain (the number and diversity of seeds arriving in a given area) is challenging, and the lack of standardization in measurement prevents cross-site comparisons. Seed trap effectiveness and accuracy of seed sorting methods are key components of seed rain estimates in need of standardization. We propose and describe a standardized protocol for evaluating the effectiveness of two seed trap types (sticky and funnel traps) and the accuracy of a seed sorting method. We used widely available seeds (arugula, quinoa, sesame and sunflower) to produce a gradient of seed size, weight and colour. Proof-of-concept was tested in a tropical grassland, where traps were set for 30 days. Our results suggest that we underestimate dispersal of seeds with less than 2 mm width that can be easily mistaken for debris and soil particles or that fail to adhere to sticky traps. Seeds on sticky traps may be more vulnerable to removal by wind and rain, whereas seeds in funnel traps are more susceptible to decay. We found no evidence of observer bias on seed sorting for funnel trap samples. However, accuracy on seed sorting for funnel trap samples tended to decline for seeds with less than 2 mm width, suggesting a size-dependence in seed retrieval success. Our standardized protocol addressing trap effectiveness and seed sorting methods will increase the reliability of data obtained in seed rain studies and allow more reliable comparisons between datasets.

Efficacy of aggregation nano gel pheromone traps on the catchability of Rhynchophorus ferrugineus (Olivier) in Egypt

Field experiments were carried out in the reclaimed land east of Cairo-Alexandria Desert Road, Village of Wardan, Giza Governorate, Egypt, to evaluate the impact of using nano-gels pheromone for the first time on the attraction of the RPW adults by pheromone traps compared to the control which is normal pheromone during two successive seasons in 2018 and 2019. Also, this study aimed to compare the efficacy of two types of trap, traditional trap (type 1) and dry funnel trap (type 2) in capturing of RPW adults. Results revealed that the nano gel pheromone traps attracted significantly more adults with an average of (4.26 and 3.56) adults/trap and total of (55.33 and 46.33) adults/trap compared to control with an average (2.69 and 2.46) and total of (35.00 and 32.00) adults/trap for the two seasons 2018 and 2019 respectively. Results indicated that the use of nano gel pheromone for the first time in field improved the trap catchability to RPW adults by 22.51 and 18.30% of total number of RPW adults captured throw out the two successive seasons respectively. In addition, there was no significant difference between the total numbers of RPW adults collected by the two tested type of traps over the two successive seasons. Furthermore, the sex ratio between males and females of total collected RPW adults found to be1: 1.43 and 1: 1.94 at 2018 and 2019 respectively.

Sampling efficiency, bias and shyness in funnel trapping aquatic newts

A lightweight, collapsible funnel trap designed for crayfish was furnished with a smaller mesh and then used to study adult breeding populations of five species of newts in five ponds in France. Observations were made in spring, at the peak of breeding activity, over an 11-year period. Annual experiments involved on average 7.7 traps and 5.3 overnight sampling sessions at 2.0 day intervals. In 95 out of 171 experiments (56%) the probability for an individual to go undetected was <1%. A trend was observed for catchability to increase with body size (Lissotriton < Ichthyosaura < Triturus). The two Triturus species involved were frequently exhaustively sampled in a single overnight session. In spite of their smaller size, L. helveticus males were more readily captured than females, presumably reflecting breeding associated locomotor activity. The numbers captured decreased over time suggesting ‘trap shyness’ to operate. We noted some predation by diving beetles (family Dytiscidae) affecting L. helveticus males in particular.

Trap Happiness and Catch Bias in Sea Lamprey Traps

Sampling fish by trapping can lead to biased conclusions about a population. We used catch data to assess differences between two types of traps for adult sea lamprey (Petromyzon marinus), submerged-funnel traps and studded-tile traps, which are angled ramps with trickle flow leading out of the water. The studded-tile trap at one river caught about 50% more females than the funnel trap. It caught males that had a smaller body size and females with a lower gonado-somatic index (GSI). The likelihood of catching lamprey in the studded-tile trap increased after they had been caught once. This was not the case for the funnel traps, which are used for mark–recapture-based population assessment of invasive sea lamprey in the Great Lakes. The apparent trap response caused by studded-tile traps may have been caused by a behavioral bias, i.e., the traps consistently attracting a subset of the population. Use of the studded-tile trap for population assessment should only be considered after more is known about its recapture bias. The differences between lamprey caught in the two trap types suggests that a variety of trapping methods needs to be employed in order to get a representative sample from a fish population.