Terrestrial firefly larvae extermination device

Abstract

To provide a device for efficiently exterminating terrestrial firefly larvae, an invasive species, while minimizing the impact on non-target organisms. [Solution] This device comprises an attractant section, which attaches the mucus of terrestrial snails to absorbent and adsorbent kite string to form a simulated mucus trail (3), and a cylindrical guide and pesticide treatment section, through which the kite string passes and whose interior is coated with mucus and insecticide, simulating the shell of a terrestrial snail. Terrestrial firefly larvae (4) are attracted by the mucus and enter the cylindrical guide section (1), where they are selectively killed by contact with the insecticide (2) coated on its inner wall. Furthermore, by connecting multiple guide sections or forming them into a ring and placing a shellfish bait in the center, the formation of a mucus trail is promoted as the snails are attracted to the device, thereby increasing the efficiency of luring the larvae. Additionally, by adjusting the diameter and length of the tube and the density of the devices, it is possible to selectively exterminate larvae of specific body sizes and mobility. For pesticide treatment, an aerosol formulation for indoor pest control is sprayed onto the inner wall of the tube.

Description

[Technical Field]

[0001] This invention relates to a device that selectively exterminates terrestrial firefly larvae that prey on snails from the ecosystem while minimizing the environmental impact of chemicals. [Background technology]

[0002] In the context of invasive alien species control, chemical control, like agricultural pests, has a comprehensive and sustained effect on target populations, making it an effective option for suppressing or eradicating those populations. Chemical control is generally more cost-effective than manual physical capture and killing. Furthermore, compared to biological control, such as the introduction of natural enemies, the behavior of chemicals released into the environment is more predictable than that of new alien species introduced as natural enemies, allowing for more reliable management. In chemical control, the selection of chemicals based on the ecology and physiology of the target species and the choice of administration method greatly influence the effectiveness of the control and the environmental impact as a side effect. In addition, when selecting this method, there is generally a trade-off between versatility and environmental impact. While spraying chemicals throughout the environment is highly versatile, all methods have a significant impact on non-target species. Selective administration of chemicals to target species using bait or pheromones reduces the environmental impact but naturally narrows the range of application.

[0003] The terrestrial firefly, the Yaeyama firefly, is native to the Yaeyama Islands of Okinawa Prefecture, but was introduced to Okinawa Island as an invasive species, threatening the terrestrial snail communities in its invaded areas. Larger than Okinawa's native fireflies and feeding more frequently, it has rapidly caused the disappearance of terrestrial snails in its invaded areas, making its eradication from Okinawa Island an urgent issue. Meanwhile, when controlling invasive species in natural environments with the goal of preserving native ecosystems, particularly endemic and rare species, the choice of control method becomes even more critical due to the negative impact on native ecosystems. Considering the burden on native terrestrial fireflies and existing ecosystems, widespread spraying of insecticides is difficult to implement. At the same time, the scale of manual capture and killing, currently the primary control method, is not considered sufficient to suppress populations.

[0004] No extermination technology has been established that targets fireflies. Currently, species-specific attractant methods, such as pheromones, targeting adult invasive fireflies have not yet reached the practical stage, and capturing and killing larvae with insecticide baits has not yet been put to practical use. Previous research has confirmed in laboratory experiments that invasive fireflies follow the movements of land snails, and has also observed that when a single firefly attacks and paralyzes a single prey, multiple fireflies will retreat into its shell and participate in the hunt.

[0005] In order to solve the current issues, based on known ecological knowledge and the applicant's own observations of food search and predatory behavior through breeding, a device was devised that guides the terrestrial firefly larvae wandering around in search of prey using a pseudo-mucus trail of terrestrial snails, coats the inside with mucus of terrestrial snails and insecticide, and then allows the larvae to enter or pass through a cylindrical structure that mimics the shell, bringing them into contact with the chemicals and exterminating the targeted invasive terrestrial fireflies. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-180196 [Non-patent literature]

[0007] [Non-Patent Document 1] Sato N “Prey-tracking behavior and prey preferences in a tree-climbing firefly” PeerJ 2019 [Non-patent document 2] Makoto Ohba, "Predatory behavior of the larvae of the firefly Luciola harakaensis and the firefly Luciola oshimaensis on the Okinawan snail Luciola spp.," Yokosuka City Museum of Natural Sciences, 2005 Summary of the Invention [Problem to be solved by the invention]

[0008] The problem to be solved is that there is no established method to effectively and selectively control invasive alien terrestrial fireflies from outdoor environments, and that surface treatments such as insecticides place a heavy burden on non-target species in the treated area. [Means for solving the problem]

[0009] The main feature of this device is that the kite string, which has high absorbency and adsorption properties, is used to absorb land snail mucus to simulate a trail and attract target species, and the tubular structure of the cut straw and the land snail mucus applied to the inner wall simulate a land snail shell, thereby inducing the burrowing behavior of the target species' larvae. The inner wall of the straw is then coated with an insecticide using an aerosol method for indoor pest control, which adheres to the exposed part of the treatment space, selectively bringing the target invasive terrestrial firefly into contact with the insecticide and killing it. [Effects of the Invention]

[0010] This device is equipped with a pseudo-trail and a pseudo-tubular structure that mimics land snails, and is designed to selectively attract and exterminate invasive terrestrial firefly larvae. Compared to conventional surface spraying of insecticides, this device significantly reduces the release of insecticides into the environment and minimizes the impact on non-target organisms. The use of this device has the following multiple effects: First, because the use of pesticides is limited to within the device, the amount of pesticide released into the environment is significantly reduced compared to surface spraying, minimizing the impact on non-target species and the surrounding environment. Second, the pseudo-mucus trail and cylindrical structure used for attraction make it easy to guide only terrestrial firefly larvae, which have the specific behavioral characteristics of chasing terrestrial snails, into the device, ensuring high selectivity. Thirdly, by adjusting the diameter and length of the tubular structure (straw) and the placement density of the device, it is possible to further select the target firefly species among terrestrial firefly larvae, and it is possible to operate the device flexibly according to local environmental conditions, making it highly adaptable and practical. This makes it possible to practically eradicate invasive firefly larvae selectively and with low environmental impact, something that was difficult to do with conventional manual capture or area-wide extermination methods. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is an explanatory diagram showing the structure and function of a device for exterminating terrestrial firefly larvae. (Example 1) [Figure 2] FIG. 2 is an explanatory diagram showing a method for implementing the device for exterminating terrestrial firefly larvae (Example 2). [Figure 3] FIG. 3 is an explanatory diagram showing a method for exterminating terrestrial firefly larvae (Example 2). [Figure 4] Figure 4 shows a model for predicting effectiveness based on field demonstration test data for the installation of the extermination device for terrestrial firefly larvae shown in Figure 3 (Example 2). DETAILED DESCRIPTION OF THE INVENTION

[0012] This invention relates to a device that utilizes the food-seeking behavior of terrestrial firefly larvae by selectively guiding the larvae with an attractant that mimics a mucus trail, and then having the larvae crawl into a cylindrical guide that mimics the shell of a terrestrial mollusk, bringing them into contact with an insecticide and exterminating them. [Example]

[0013] Figure 1 is an explanatory diagram showing the structure of one embodiment of the device of this invention. In the figure, 1 is a cylindrical guide section modeled after the shell of a land snail, made by cutting an ordinary straw to a specified length. The inner wall 2 of the cylindrical guide section 1 is coated with land snail mucus and an insecticide. 3 is a pseudo-mucus trail formed by attaching land snail mucus to a kite string, which is connected by passing through the inside of the cylindrical guide section 2, and 4 is a terrestrial firefly larvae that is guided by the pseudo-trail and exhibits burrowing behavior. 5 shows an example of a configuration in which multiple cylindrical guide sections are connected.

[0014] The artificial slime trail 3 is formed by passing actual land snails through a kite string, which has excellent water absorption and adsorption properties, and then attaching the snails' mucus to the string. This kite string can be arranged in a straight or branched shape depending on the installation environment, and can be placed along the larvae's wandering route to efficiently guide them.

[0015] The cylindrical guide section 1 is modeled after the shell of a land snail, and by applying mucus to the inner wall, it recreates an environment that is easy for larvae to invade. The inner wall is also coated with an insecticide, which kills the larvae when they come into contact with the agent as they pass through or burrow into it. An aerosol formulation for indoor pest control can be used as the insecticide, and it can be sprayed and applied to the inner wall 2 of the cylindrical guide section 1 in advance. [Example]

[0016] As shown in Figures 2 and 3, multiple cylindrical guide sections 1 are connected by a pseudo-mucus trail 3, and the trail can be extended by extending the kite string as shown at 7. Also, by configuring it in a ring as shown at 6, the mucus is naturally applied to the land snails as they move towards the bait 8 placed in the center, increasing the efficiency of guiding the larvae. This makes it possible to efficiently guide and eliminate invasive firefly larvae. [Example]

[0017] By adjusting the diameter and length of the cylindrical guide part 1 or by adjusting the placement density of the entire device, it is possible to selectively act on the target firefly larvae according to their body size and mobility. For example, higher selectivity can be achieved by setting the inner diameter wider when targeting large species or large larvae nearing the final stage, and narrower when targeting small species or small young larvae.

[0018] As can be seen from the results of the field demonstration test shown in Figure 4, the device of this invention exhibits a more cost-effective extermination effect on targeted invasive species than conventional manual capture and killing, and is also capable of significantly reducing the impact on non-target species compared to area-wide chemical spraying. [Explanation of symbols]

[0019] 1. Cylindrical guide section modeled after the shell of a land snail 2. The inner wall of the cylindrical guide is coated with land snail mucus and insecticide. 3. Pseudo-mucus trail made by attaching land snail mucus to kite string 4. Encouraging terrestrial firefly larvae to burrow 5. Multiple cylindrical guide sections are connected by pseudo-mucus trails 6. Multiple connected devices are arranged in a ring 7. Pseudomucus Trail Extension 8. Food for land snails

Claims

1. An extermination device for terrestrial firefly larvae, comprising: an attracting section having a pseudo-mucus trail for attracting the larvae, formed by attaching the mucus of terrestrial snails to a kite string having water-absorbing and adsorptive properties; a cylindrical guide section, a tubular structure through which the kite string passes, having a shape imitating the shell of a terrestrial snail, with the mucus applied to its inner wall to encourage the larvae to burrow inside; and a chemical treatment section, in which an insecticide is applied to the inner wall of the cylindrical guide section, so that the larvae come into contact with the chemical as they pass through.

2. The extermination device described in claim 1 is characterized in that multiple cylindrical guide sections are connected by the attracting sections to form a ring, and bait for land snails is placed in the center of the ring, thereby promoting the formation of a mucus trail toward the device as the snails move, thereby increasing the efficiency of guiding the larvae.

3. 3. The extermination device according to claim 1 or 2, characterized in that the diameter, length, or placement density of the extermination device is adjusted to selectively act on firefly larvae having a specific body size or mobility.

4. In the extermination device described in any one of claims 1 to 3, an aerosol formulation for indoor pest control is sprayed and applied to the inner wall of the cylindrical guide section in advance in the chemical treatment section.

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