Source: UNIVERSITY OF GUAM UOG STATION submitted to NRP
ESTIMATING THE EFFECT OF LITTLE FIRE ANT, WASMANNIA AUROPUNCTATA, ON FOREST INSECT DIVERSITY AND COMMUNITY STRUCTURE IN THE MARIANA ISLANDS.
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
Reporting Frequency
Annual
Accession No.
0228405
Grant No.
(N/A)
Cumulative Award Amt.
(N/A)
Proposal No.
(N/A)
Multistate No.
(N/A)
Project Start Date
Oct 1, 2012
Project End Date
Sep 30, 2017
Grant Year
(N/A)
Program Code
[(N/A)]- (N/A)
Recipient Organization
UNIVERSITY OF GUAM UOG STATION
(N/A)
MANGILAO,GU 96913
Performing Department
Experiment Station
Non Technical Summary
Numerous alien, invasive ants have been introduced over the years into Guam that established extensive populations throughout its forests and inhabited areas (Table 1). The most recent invasive ant to establish on Guam is the little fire ant (LFA), Wasmannia auropunctata, which was first identified in a karst-limestone forest in northern Guam in November 2011. Wasmannia auropunctata is considered among the 100 most serious invasive pests worldwide, and poses serious threats to human health, livestock, and the environment in areas where it has been introduced. Though small, the ants possess a powerful sting sufficient to cause debility and, under certain conditions, death to the elderly, to young children, and to animals. Introduction into an insular environment, such as those represented by the Mariana Islands is likely to disrupt fragile island ecosystems by eliminating indigenous fauna and harming flora.
Animal Health Component
(N/A)
Research Effort Categories
Basic
(N/A)
Applied
(N/A)
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
21106401130100%
Goals / Objectives
Determine the impact of Guam's LFA infestation on forest invertebrate diversity and ant community structure.
Project Methods
A survey of ants and other invertebrates will be conducted LFA infested and non-infested areas in the karst-limestone forests of Guam and in similar non LFA infested sites on adjacent islands in the CNMI. A modified version of "The Ants of the Leaf Litter (ALL) Protocol" (Agosti and Alonso 2000) will be employed when sampling invertebrates in leaf litter in Guam. In brief, the ALL Protocol requires at least one 200 m transect with 20 sampling points at 10 m intervals over a 48 hr time period. At each sampling point leaf litter is collected from a 1 m2 quadrat and sifted. In this study the number of samples will be adjusted to match the number of extractions at a given time that can be handled by our laboratory at the University of Guam. Invertebrates in sifted leaf litter will be extracted in Berlese funnels, instead of using Winkler extraction bags. A low wattage light bulb will provide light and heat in each extraction funnel, which will allow the litter sample to dry out more quickly and uniformly than normally occurs in Winkler bags in the humid tropics. This procedure should yield an equivalent extraction, if not higher, of the total invertebrates collected in the field (Sakchoowong et al. 2007). In addition, invertebrates will be collected from a pitfall trap placed along the transect and additional inspections will be made of surrounding dead wood, soil, and plant material. Ants and other invertebrates will initially be sorted to morpho-species, and stored in 95% ethanol in labeled vials until further identification can be performed. Data will be statistically analyzed to compare species richness, habitat evenness, and community structure within LFA infested areas with non-LFA infested areas on Guam and adjacent islands (Cerda et al. 2012). Ant identifications will be performed by specialists at the University of Guam with verification as needed by collaborators in Washington state (Dr. L. Hansen, Department of Biology, Spokane Falls Community College), Hawaii (Dr. Cas Vanderwoude, University of Hawaii-Hilo) and New York (Dr. Ronald Clouse, American Museum of Natural History). Other invertebrates collected from sifted litter samples will also be identified to the lowest possible taxonomic level. Voucher specimens of ants and other insects will be maintained in the Wilfred Leon Guerrero Entomology Museum at the University of Guam.

Progress 10/01/12 to 09/30/17

Outputs
Target Audience:The target audiences have been the agricultural and scientific communities on Guam, in the CNMI, and throughout Micronesia, that are threatened by invasion of Wasmannia auropunctata. Also targeted were specific government agencies on Guam and in the CNMI that are charged with identifying, intercepting, and controlling W. aurponctata within their own jurisdictions. These include the Department of Lands and Natural Resources, the Department of Agriculture, and the Department of Forestry in the CNMI; and the Department of Aquatic and Wildlife Resources and the Department of Agriculture on Guam. Also included were the National Park Service and the Department of Defense on Guam and Saipan Changes/Problems:The chronic financial shortages over the years, and especially the severe financial shortfal experienced by the University of Guam during 2017, made it difficult to hire temporary personnel, process purchase orders and obtain supplies, and to travel to sampling sites in the CNMI. UOG's financial situation began to improve during late spring of 2017 and allowed project funds to be spent as needed, but beurocratic hindrances still remain serious obstacles to carrying out project objectives. What opportunities for training and professional development has the project provided?Two undergraduate students and one graduate student were trained to identify ants from Micronesia to the species level, as well as recognize morphotypes of other invertebrates. These students, and toher students working in R. Miller's laboratory, were trained in the use of leaf litter sifters, plot layout, extraction procedures using Winkler bags and Berlese funnels. and were shown how to copute diversity indices used to analyze collection data from each site on Guam and in the CNMI. How have the results been disseminated to communities of interest?Results of past and ongoing surveys have been shared with other entomologists, ecologists, and natural resource managers on Guam and the CNMI, and in various workshops and meetings involving personnel from government agencies, federal agencies, and private environmental and pest control companies on Guam and in the CNMI. Presentations included lectures delievered in local EPA pesticide training sessions, and at the First Annual meeting of Terrestrial Ecologists held at Guam Community College in November on Guam. A poster summarizing progress and the state of data analysis at the time of the poster preparation was prepared for dispaly at the annual meeting of the Entomological Society of America in Reno, NV, A second poster was also prepared and displayed at the meeting on guam mentioned perviously. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? The initial nalysis of samples of ants from forest and agricltural sites on Guam, Tinian, Rota, and Saipan has been completed. Ants and other invertebrates, collected from sifted forest leaf litter and from protein and sugar baits, were sorted to morphospecies and counted. All morpho-species were identified to the lowest taxonomic level possible. All ants were identified to species. Verification of data is ongoing. Diversity and community evenness indices are being computed from the different sites collected on each island, and comparisons made in LFA-infested and non-infested areas. We cintinue to sample ants in both Guam in LFA infested areas and non infested areas, and in the CNMI where LFA has yet to be found. These data have been added to our master ant database.

Publications

  • Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Santos, J., R. Miller, M. Raymundo, L.R. Sablan, H. White, and J. McBryde. 2015. Invertebrate diversity in little fire ant (LFA), Wasmannia auropunctata, infestations in Costa rica and in the recently infested Micronesian island of Guam. poster presented at Ent. Soc. Amer.,Nov. 2015, Minneapolois MN.
  • Type: Journal Articles Status: Submitted Year Published: 2016 Citation: Freedman, M.G., R.H. Miller, and H.S. Rogers. Landscape-level bird loss is associated with an increase in the prevalence of honeydew-producing insects and invasive ants. (submitted Sept 2016).
  • Type: Journal Articles Status: Published Year Published: 2012 Citation: Raymundo, M.L. and R.H. Miller. 2012. Little fire ant, Wasmannia auropunctata (Roger) (Hymenoptera: Formicidae), established at several locations on Guam. Proc. Hawaiian Entomol. Soc. 44: 85-87.


Progress 10/01/16 to 09/30/17

Outputs
Target Audience:The target audiences are the agricultural and scientific communities on Guam, in the CNMI, and throughout Micronesia, that are threatened by invasion of Wasmannia auropunctata. Also targeted are specific government agencies on Guam and in the CNMI that are charged with identifying, intercepting, and controlling W. aurponctata within their own jurisdictions. These include the Department of Lands and Natural Resources, the Department of Agriculture, and the Department of Forestry in the CNMI; and the Department of Aquatic and Wildlife Resources and the Department of Agriculture on Guam. Also included are the National Park Service and the Department of Defense on Guam and Saipan. Changes/Problems:The severe financial shortfals experienced by the University of Guam during 2017 made it difficult to hire temporary personnel, process purchase orders and obtain supplies, and to travel to sampling sites in the CNMI. UOG's financial situation began to improve during late spring of 2017 and allowed project funds to be spent as needed. What opportunities for training and professional development has the project provided?An undergraduate student was trained to identify ants from Micronesia to the species level, as well as recognize morphotypes of other invertebrates. This student, and toher students working in R. Miller's laboratory, were trained in the use of leaf litter sifters, plot layout, extraction procedures using Winkler bags and Berlese funnels. and were shown how to copute diversity indices used to analyze collection data from each site on Guam and in the CNMI How have the results been disseminated to communities of interest?Results of past and ongoing surveys have been shared with other entomologists, ecologists, and natural resource managers on Guam and the CNMI, and in various workshops and meetings involving personnel from government agencies, federal agencies, and private environmental and pest control companies on Guam and in the CNMI. Presentations included lectures delievered in local EPA pesticide training sessions, and at the First Annual meeting of Terrestrial Ecologists held at Guam Community College in November on Guam. A poster summarizing progress and the current state of data analysis was prepared for dispaly at the annual meeting of the Entomological Society of America. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? The initial nalysis of samples of ants from forest and agricltural sites on Guam, Tinian, Rota, and Saipan has been completed. Ants and other invertebrates, collected from sifted forest leaf litter and from protein and sugar baits, were sorted to morpho-species and counted. All morpho-species were identified to the lowest taxonomic level possible. All ants were identified to species. Verification of data is ongoing. Diversity and community evenness indices are being computed from the different sites collected on each island, and comparisons made in LFA-infested and non-infested areas. We cintinue to sample ants in both Guam in W. auropunctata infested areas and non infested areas, and in the CNMI where W. auropunctata has yet to be found. These data have been added to our master ant database.

Publications


    Progress 10/01/15 to 09/30/16

    Outputs
    Target Audience:The target audiencesaretheagricultural and scientific communities on Guam, in the CNMI, and throughout Micronesia, that are threatened by invasion of Wasmannia auropunctata. Also targeted are specific government agencies on Guam and in the CNMI that are charged with identifying, intercepting, and controlling W. aurponctata within their own jurisdictions. Changes/Problems:Severe financial shortfals at the Univeristy of Guam have made it difficult to hire temporary personnel and process purchase orders for computer software and hardware, and to travel to sampling sites in the CNMI. We will continue to work with UOG financial and human resource officers to remedy these problems. What opportunities for training and professional development has the project provided?Graduate and undergraduate students were trained to identify ants from Micronesia to the species level, as well as recognize morphotypes of other invertebrates. These students were also trained in the use of leaf litter sifters, plot layout, extraction procedures using Winkler bags and Berlese funnels. and were shown how to copute diversity indices used to analyze collection data from each site. How have the results been disseminated to communities of interest?Results have been shared with other entomologists, ecologists, and natural resource managers on Guam, andin various workshops targetting plant protection and quarantine specialists from Guam,the CNMI, and other islands of Micronesia. A poster summarizing research resultshas beenprepared for presentation at workshops dealing with invasive insect pests, and at professional meetings. What do you plan to do during the next reporting period to accomplish the goals?Most of the taxonomic work in identifying morpho-species of invertebrates, and of ants, has been accomplished. Wehave incorporated results from the Mariana Islands samples with those collected using similar techniques from Costa Rica, which is part of the home range of Wasmannia auopunctata. We are currently proofing the extensive databgse,verifying ant identifications, and examining various statistical tests for evaluating community diversity and similarities between the sites studied. As stated in past reports,weplan on publishingresults in a scientific journaland anddiscussing them atprofessional meetings. Our ultimate object isdemostrate the similarities and differences in the effects of W. auropunctata on invertebrate fauna inan isolated insular ecosystem as well ascompare the effects of W. auropunctatainfestation in humid tropical island environmenta to the richly diverse forests of the ant's home range in mid-elevation Costa Rican forests.

    Impacts
    What was accomplished under these goals? Analysis of samples of ants from forest and agricltural sites on Guam, Tinian, Rota, and Saipanhas beencompleted. Ants and other invertebrates, collected from sifted forest leaf litter and from protein and sugar baits, have beensorted to morpho-species and counted. All morpho-species were identified to the lowest taxonomic level possible. All ants were identified to species. Diversity and community evenness indicesare beingcomputed from the different sites collected on each island, and comparisons made in LFA-infested and non-infested areas. We have continued to sample ants in both Guam in W. auropunctata infested areas and non infested areas, and in the CNMI which to date has not been infested by W. auropunctata. These data have been added to our intial sampling database.

    Publications


      Progress 10/01/14 to 09/30/15

      Outputs
      Target Audience:The target audience is the agricultural and scientific communities on Guam, in the CNMI, and throughout Micronesia that are threatened by invasion of Wasmannia auropunctata. Also targeted are specific government agencies on Guam and in the CNMI that are charged with identifying, intercepting, and controlling W. aurponctata within their own jurisdictions. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Graduate and undergraduate students were trained to identify ants from Micronesia to the species level, as well as recognize morphotypes of other invertebrates. These students were also trained in the use of leaf litter sifters, plot layout, extraction procedures using Winkler bags and Berlese funnels. they were able to compute community evenness and diversity indices based on their samples at each site. How have the results been disseminated to communities of interest?Preliminary results have been shared informally with other entomologists, ecologists, and natural resource managers on Guam and in the CNMI. A poster summarizing research results was prepared for presentation at professional meetings. What do you plan to do during the next reporting period to accomplish the goals?Most of the taxonomic work in identifying morpho-species of invertebrates, and of ants, has been accomplished. We are currentlyincorporating results from the Mariana Islands samples with those collected using similar techniques from Costa Rica, whichis part of the home range of Wasmannia auopunctata. We plan on publishing these comparisons in a scientific journaland and at professional meetings andhope to demostrate the similarities and differences in the effects of W. auropunctata on an isolated insular ecosystem as compared to the richly diverse forests of the ant's home range in Costa Rica.

      Impacts
      What was accomplished under these goals? Analysis of samplesof ants from forest and agricltural sites on Guam, Tinian, Rota, and Saipan was completed. Ants and other invertebrates, collected from sifted forest leaf litter and from protein and sugar baits, were sorted to morpho-species and counted. All morpho-species were identified to the lowest taxonomic level possible. All ants were identified to species. Diversity and community evenness indices were computed from the different sites collected on each island.

      Publications

      • Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Santos, J., R. Miller, M. Raymundo, L.R. Sablan, H. White, and J. McBryde. 2015. Invertebrate diversity in little fire ant (LFA), Wasmannia auropunctata, infestations in Costa rica and in the recently infested Micronesian island of Guam. poster presented at Ent. Soc. Amer.,Nov. 2015, Minneapolois MN.


      Progress 10/01/13 to 09/30/14

      Outputs
      Target Audience: the target audience is the agricultural and scientific communities on Guam, in the CNMI, and throughout Micronesia thatare threatened by invasion of Wasmannia auropunctata. Also targeted are specific government agencies on Guam and in the CNMI that are charged with identifying, intercepting, and controlling W. aurponctata within their own jurisdictions. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Graduate and undergraduate students were trained to identify ants from Micronesiato the species level, as well as recognize morphotypes of other invertebrates. These students were also trained in the use of leaf litter sifters, plot layout, extraction procedures using Winkler bags and Berlese funnels. they were able to compute community evenness and diversity indicesbased ontheir samples at each site. How have the results been disseminated to communities of interest? Preliminary results have been shared informally with other entomologists, ecologists,and natural resource managers on Guam and in the CNMI. What do you plan to do during the next reporting period to accomplish the goals? While most of the taxonomic work in identifying morpho-species of invertebrates, and of ants, has been accomplished, we plan incorporate results from the Mariana Islands samples with those collected using similar techniques from Costa Rica, which is part of the home range of Wasmannia auopunctata. We plan on publishing these comparisons in a scientific journal, and hope to demostrate the similarities and differences in the effects of W. auropunctataon an isolated insular ecosystem as compared tothe richly diverse forests of the ant's home range in Costa Rica.

      Impacts
      What was accomplished under these goals? Sampling of ants from forest and agricltural sites on Guam, Tinian, Rota, and Saipan was completed. Ants and other invertebrates,collected fromsifted forest leaf litter and from protein and sugar baits, were preserved in ethanol and sorted to morpho-species and counted. All morpho-species were identified to the lowest taxonomic level possible. All ants were identified to species. Diversity and community evenness indices were computed from the different sites collected on each island.

      Publications


        Progress 10/01/12 to 09/30/13

        Outputs
        OUTPUTS: Seven forest sites on the island of Saipan, one site on Tinian, and three sites on Rota in the Commonwealth of the Northern Marianas (CNMI), were sampled for invertebrates including little fire ant. Samples of invertebrates were collected by collecting and sifting all leaf litter down to the soil surface in a one square meter quadrat. Leaf litter samples were stored in a sealed plastic bag until they were deposited in a Berlese funnel where they were extracted into 95% ethanol using a low wattage light bulb for 72 hours. Samples stored in ethanol were cleaned to remove debris, then individual specimens from each sample were sorted and counted under a microscope. Individual morphospecies were assigned identification numbers until they could be identified. Sampling, extraction, sorting and identification are ongoing. PARTICIPANTS: Participants in this project include: Project Director: Ross Miller - Professor of Entomology, University of Guam Technical Assistants: Lee Roy Sablan and Robert Deleon Guerrero located at the Northern Marianas College in Saipan - collected and extracted leaf little samples from CNMI sites. their participation is funded by a USDA-APHIS project on invasive species in the CNMI; Julie Anne Duay and Christina Nguyen - recently hired as part time technicians employed by the project at the University of Guam to sort extracted litter samples and collect litter samples from Guam forests. Maia Raymundo - research assistant at the University of Guam funded by a USDA-APHID-CAPS project on little fire ant surveillance. She provides taxonomic expertise and training in ant taxonomy to other project participants. Partner Institutions: Northern Marianas College - provides laboratory space for Berlese funnel extractions. All samples from CNMI must be extracted and preserved in ethanol in the NMC laboratory before being transported to Guam for further sorting and identification. Training opportunities: Maia Raymundo provide a one day training workshop for NMC personnel in February 2013 on ant taxonomy; R. Miller trained NMC personnel, and UOG research assistants in how to sample and extract invertebrates from leaf litter, and in general invertebrate taxonomy. TARGET AUDIENCES: Nothing significant to report during this reporting period. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

        Impacts
        Although data are still being analyzed and collected, it is clear that there are differences in the level of diversity and composition of the invertebrate populations in different forests on the different islands. Most of the ants collected appear to be common tramp ant species, and no little fire ants have been found anywhere except in forests in northern Guam. Little fire has yet to arrive, or at least be detected, in the CNMI.

        Publications

        • No publications reported this period