Persistence, Prevalence, and Emergence Patterns of Pasture Tunnel Moth - Essay Example

? Persistence, Prevalence and Emergence Patterns of Pasture Tunnel Moth (Philobota spp Teacher               Outline of the New Zealand Lepidoptera The following are the 22 families under the order Lepidoptera found in New Zealand (Alphabetical List, 2012): Batrachedridae Choreutidae Crambidae Depressariidae Elachistidae Gelechiidae Geometridae Glyphipterigidae Gracillariidae Hepialidae Micropterigidae Mnesarchaeidae Nepticulidae Noctuidae Nymphalidae Oecophoridae Plutellidae Psychidae Pterophoridae Tineidae Tortricidae Yponomeutidae Descriptions of Particular Families of Moths The family Pterophoridae has wings that are unusually modified and these moth species usually look like a piece of dried grass, which help them escape predators. They are stem or root borers and some species are also leaf browsers (‘Plume Moth’, 2012). The family Geometridae, or the geometer moths, are usually the inchworms that are said to “measure the earth” as they move about. This is an extremely large family of moths with an estimated 35,000 species. However, several geometers are known to be terrible pests. The caterpillars, known as loopers, inchworms or spanworms, feed on plants while some species are even carnivorous (‘Looper’, 2012). The family Noctuidae, or the owlet moths, are not only numerous in species but also robust – and they are the largest family. They have hind wings of bright colors. They are usually flying at night. They also invade flowers as many are attracted to sugar and nectar. Moreover, their larvae are crop pests (‘Cutworm Moth’, 2012). The family Cambridae is colored and patterned moths characterized by a special structure in the ears known as “praecinctorium,” which is responsible for joining the two tympanic membranes of the ears. The harmful Cambrid moth, or Grass Moth, has larvae which are typical stem borers of many important crops (‘Grass Moth’, 2012). Moths that are Pests in New Zealand Some moth pests in New Zealand include the Porina moth, Codling moth, Oriental fruit moth, White Butterfly, Diamondback Moth, and the Potato Tuber Moth (‘Story: Insect pests of crops’, 2012). The Status of Philobota spp in Australia and in New Zealand In Australia, the Philobota species of moth, or the pasture tunnel moths, are grass feeders (Moate et al., 2012). The so-called tunnel moths make a silk lined tunnel and that during night time or winter, the caterpillar of the tunnel moth gathers grass foliage and drags them back into their tunnels. The caterpillars are very small and may be quote difficult to notice for they measure around 35 mm long only and 3 mm across (‘New pasture pest’, 2010). Pasture tunnel moths usually live in areas with higher rainfall, and they can cause significant damage to clovers, as well as annual and perennial grasses. The larvae are usually grey-colored in their bodies with black heads. The adult moth, on the other hand, is long and has a creamy-white color. The pasture tunnel moth usually cause the greatest damage during the months of July and August, during the rainy months, for rain has a great factors in stimulating this species of moth to feed more (‘Pasture tunnel moth’, 2009). Moreover, the pasture tunnel moth affects cereal crops (Perry et al., 2011). The first time that Philobota species were identified in New Zealand was in February 2010 at the Ruakura Research Center in Hamilton, New Zealand. The migrant species are actually native to Australia, of which there are around 400 species, and where a number of these species are regarded as “minor pests of pasture” because it merely feeds on grass such as tall fescue trials and perennial ryegrass (Popay & Gunawardana, 2011). In case a New Zealand resident sees pasture tunnel moths, they should immediately contact MAF Biosecurity New Zealand (‘New pasture pest’, 2010). Based on the table below from the Asia & Pacific Plant Commission Protection, the first sighting of Philobota species in New Zealand was in 2010, and it was perhaps through the wind that they were blown from Australia to this country. Moreover, since the status of the Australian Pasture Tunnel Moth in New Zealand is now established and since the affected area is “likely to be widespread”, there is a great possibility of a Philobota invasion of New Zealand (‘New Zealand’, 2011). Moreover, $23,000 has already been used to fund the research for this particular invasive pest species (‘New Zealand’, 2011). Eradication or internal quarantine actions taken against economically important species Name of species Australian Pasture Tunnel Moth (Philobota sp.) Year of first discovery 2010 Pathway Unknown, potential wind-blown migrant Location of first discovery Waikato Area affected [ha] 1 known site, however considered to likely be widespread. Area treated [ha] Control method Surveillance conducted Expenditure NZD 2010 $23,300 Status Established Philobota Investigation Aim of the Study The aim for the project is to determine the emergence patterns of the Philobota moth, as well as to know the possible factors that cause these emergence patterns and to know the location of the tunnels used by the Philobota larvae. Introduction The Philobota species of moth have migrated from New Zealand, and have caterpillars that “cut off live pieces of foliage and drag them back in to their tunnels to feed on later” with very active larvae in winter and pupae in spring (‘Have You Seen Caterpillars’, 2010). Method In order to conduct the experiment, we searched for the tunnels constructed by the Philobota larvae in the vegetation at AgResearch. We set up light traps or boxes with light and counted and identified the moths that were caught in the light traps. Result The number of moths caught in the light trap and the total number of moths from Oct. 1, 2012 up to Nov. 2, 2012 is presented in the following graphs: Analysis With the light traps, there are relatively more moths caught before and after the wet night on Oct. 19 compared to other days. There are 8, 4 and 10 moths caught during the 3 days before Oct. 19, and 8, 10, and 13 moths caught in the light trap during the 3 days after Oct. 19. It seems that rainfall also makes the moths favor the light trap more or makes them search for the light. Since there is no specific time when the moths were caught, then it cannot be determined whether daytime or nighttime affects the moth’s attraction towards the light. Moreover, based on data gathered, the number of moths also increased before and after a very wet night like the one on Oct. 19. The total number of moths caught from Oct. 16, 17 and 18 are 11, 4, and 11 respectively, with 8 on Oct. 19. After this, 12, 15 and 14 moths are caught on Oct. 21, 22 and 23 respectively. It therefore seems that rainfall favors the emergence of the Philobota moths. Nevertheless, the independent variables are too few. In fact, there is only one – rainfall. Therefore, if the study must be repeated, then more variables are needed such as the time of day that the moths were caught, like whether they were caught in the morning or evening or afternoon, or dawn or dusk. Their reaction to the light trap might be affected by the time of the day because morning is too bright and the light trap is less visible, while evening is too dark and the light trap is more visible. Another important variable is the temperature of the place or the day when the moths were gathered, since these moths might favor low temperature like after the rainfall because many of them were caught before and after the rainfall. Lastly, we also have to consider the type of weather because we are not sure if rainfall really causes a lot of moths to go out. Sunny days, gloomy weather, snow and frost may have different effects on the moths or maybe just similar to rainfall. Conclusion Based on the data gathered, the moths seem to be attracted to the light before and after a wet night. Moreover, using the same data, one can conclude that more moths emerge before and after a wet night. It, therefore, seems that rainfall has a positive factor in the emergence of the Philobota moths. However, other variables are necessary. References Alphabetical List by Family. (2012). Retrieved Nov. 7, 2012, from Landcare Research: http://www.landcareresearch.co.nz/resources/collections/nzac/holdings/lepidoptera/part-2-alphabetical-list-by-family Cutworm Moth. (2012). Retrieved Nov. 6, 2012, from Nature Watch New Zealand: http://naturewatch.org.nz/taxa/23624-Noctuidae Grass Moth. (2012). Retrieved Nov. 8, 2012, from Nature Watch New Zealand: http://naturewatch.org.nz/taxa/14816-Crambidae Have You Seen Caterpillars of the Australian Pasture Tunnel Moth. (2010). Retrieved Nov. 7, 2012, from Biosecurity New Zealand: http://www.biosecurity.govt.nz/files/pests/australian-pasture-tunnel-moth-fact-sheet.pdf Looper. (2012). Retrieved Nov. 6, 2012, from Nature Watch New Zealand: http://naturewatch.org.nz/taxa/17759-Geometridae Moate, P. J., Williams, S. R. O., Grainger, C., Hannah, M. C. & Mapleson, D. (2012). Effects of wild-type, AR1 and AR37 endophyte-infected perennial ryegrass on dairy production in Victoria, Australia. Retrieved October 11, 2012, from Animal Production Science: http://www.publish.csiro.au/paper/AN12126.htm New pasture pest to keep an eye out for. (2010). Retrieved Nov. 7, 2012, from Bayer Crop Science: http://www.sg.bayercropscience.co.nz/content/new-pasture-pest-keep-eye-out New Zealand. (2011). Retrieved Nov. 8, 2012, from the Asia & Pacific Plant Commission Protection: http://www.apppc.org/file_uploaded/1311241691_ppf_-_New_Zealand.pdf Pasteur tunnel moth. (2009). Retrieved Nov. 7, 2012, from Pest Facts: http://www.cesaraustralia.com/sustainable-agriculture/pestfacts-south-eastern/past-issues/2009/pestfacts-issue-no-5-1st-july-2009/pasture-tunnel-moth/ Perry, K., Caon, G. & DeGraaf, H. (2011). Pasteur tunnel moth in cereals. Retrieved Nov. 7, 2012, from the Sardi Entomology Pest Facts: http://www.sardi.sa.gov.au/__data/assets/pdf_file/0006/156633/PestFacts_Issue_5_2011.pdf Plume Moth. (2012). Retrieved October 11, 2012, from Nature Watch New Zealand: http://naturewatch.org.nz/taxa/27778-Pterophoridae Popay, A. J. & Gunawardana (2011). Philobota sp. (Lepidoptera: Oecophoridae), a potential new pasture pest in New Zealand. Retrieved Nov. 7, 2012, from the New Zealand Plant Protection Society: http://www.nzpps.org/nzpp_abstract.php?paper=642851 Story: Insect Pests of Crops, Pasture and Forestry. (2012). Retrieved Nov. 7, 2012, from TEARA: http://www.teara.govt.nz/en/insect-pests-of-crops-pasture-and-forestry/2 Read More