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Mishra M, Guria R, Paul S, Baraj B, Santos CAG, Dos Santos CAC, Silva RMD. Geo-ecological, shoreline dynamic, and flooding impacts of Cyclonic Storm Mocha: A geospatial analysis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 917:170230. [PMID: 38278234 DOI: 10.1016/j.scitotenv.2024.170230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 12/28/2023] [Accepted: 01/15/2024] [Indexed: 01/28/2024]
Abstract
This research comprehensively assesses the aftermath of Cyclonic Storm Mocha, focusing on the coastal zones of Rakhine State and the Chittagong Division, spanning Myanmar and Bangladesh. The investigation emphasizes the impacts on coastal ecology, shoreline dynamics, flooding patterns, and meteorological variations. Employed were multiple vegetation indices-Normalized Difference Vegetation Index (NDVI), Enhanced Vegetation Index (EVI), Modified Vegetation Condition Index (mVCI), Disaster Vegetation Damage Index (DVDI), and Fractional Vegetation Cover (FVC)-to evaluate ecological consequences. The Digital Shoreline Assessment System (DSAS) aided in determining shoreline alterations pre- and post-cyclone. Soil exposure and flood extents were scrutinized using the Bare Soil Index (BSI) and Modified Normalized Difference Water Index (MNDWI), respectively. Additionally, the study encompassed an analysis of microclimatic variables, comparing meteorological data across pre- and post-cyclone periods. Findings indicate significant ecological impacts: an estimated 8985.46 km2 of dense vegetation (NDVI >0.6) was adversely affected. Post-cyclone, there was a discernible reduction in EVI values. The mean mVCI shifted negatively from -0.18 to -0.33, and the mean FVC decreased from 0.39 to 0.33. The DVDI underscored considerable vegetation damage in various areas, underscoring the cyclone's extensive impact. Meteorological analysis revealed a 245 % increase in rainfall (20.22 mm on May 14, 2023 compared to the May average of 5.86 mm), and significant increases in relative humidity (14 %) and wind speed (205 %). Erosion was observed along 74.60 % of the studied shoreline. These insights are pivotal for developing comprehensive strategies aimed at the rehabilitation and conservation of critical coastal ecosystems. They provide vital data for emergency response initiatives and offer resources for entities engaged in enhancing coastal resilience and protecting local community livelihoods.
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Affiliation(s)
- Manoranjan Mishra
- Department of Geography, Fakir Mohan University, Vyasa Vihar, Nuapadhi, Balasore 756089, Odisha, India.
| | - Rajkumar Guria
- Department of Geography, Fakir Mohan University, Vyasa Vihar, Nuapadhi, Balasore 756089, Odisha, India
| | - Suman Paul
- Department of Geography, Fakir Mohan University, Vyasa Vihar, Nuapadhi, Balasore 756089, Odisha, India
| | - Biswaranjan Baraj
- Department of Geography, Fakir Mohan University, Vyasa Vihar, Nuapadhi, Balasore 756089, Odisha, India
| | - Celso Augusto Guimarães Santos
- Department of Civil and Environmental Engineering, Federal University of Paraíba, João Pessoa 58051-900, Paraíba, Brazil.
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Do Invasive Mammal Eradications from Islands Support Climate Change Adaptation and Mitigation? CLIMATE 2021. [DOI: 10.3390/cli9120172] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Climate change represents a planetary emergency that is exacerbating the loss of native biodiversity. In response, efforts promoting climate change adaptation strategies that improve ecosystem resilience and/or mitigate climate impacts are paramount. Invasive Alien Species are a key threat to islands globally, where strategies such as preventing establishment (biosecurity), and eradication, especially invasive mammals, have proven effective for reducing native biodiversity loss and can also advance ecosystem resilience and create refugia for native species at risk from climate change. Furthermore, there is growing evidence that successful eradications may also contribute to mitigating climate change. Given the cross-sector potential for eradications to reduce climate impacts alongside native biodiversity conservation, we sought to understand when conservation managers and funders explicitly sought to use or fund the eradication of invasive mammals from islands to achieve positive climate outcomes. To provide context, we first summarized available literature of the synergistic relationship between invasive species and climate change, including case studies where invasive mammal eradications served to meet climate adaptation or mitigation solutions. Second, we conducted a systematic review of the literature and eradication-related conference proceedings to identify when these synergistic effects of climate and invasive species were explicitly addressed through eradication practices. Third, we reviewed projects from four large funding entities known to support climate change solutions and/or native biodiversity conservation efforts and identified when eradications were funded in a climate change context. The combined results of our case study summary paired with systematic reviews found that, although eradicating invasive mammals from islands is an effective climate adaptation strategy, island eradications are poorly represented within the climate change adaptation and mitigation funding framework. We believe this is a lost opportunity and encourage eradication practitioners and funders of climate change adaptation to leverage this extremely effective nature-based tool into positive conservation and climate resilience solutions.
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Toffa J, Loko YLE, Djedatin G, Gbemavo CD, Orobiyi A, Tchakpa C, Ewedje EE, Sabot F. Rice pests in the Republic of Benin: farmers' perceptions, knowledge and management practices. PEST MANAGEMENT SCIENCE 2021; 77:5058-5071. [PMID: 34227252 DOI: 10.1002/ps.6546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 07/06/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND Rice (Oryza spp) is one of the most consumed cereals in the Republic of Benin. However, rice production is threatened by various pests, which lead to important yield losses. For the development of integrated management strategies responding to the farmers' realities, it is important to document their perceptions, knowledge and management of rice pests. Surveys involving 418 rice farmers to 21 ethnic groups through 39 villages were performed using rural appraisal tools. RESULTS Farmers perceived birds, specifically weavers as the most important rice pests. The surveyed farmers also identified the variegated grasshopper, Zonocerus variegatus L. and rice brown leaf spots [Curvularia lunata (Wakker) Boedijn] as the main pests in the northern region, the pink stem borer, Sesamia calamistis Hampson and rice blast (Magnaporthe grisea (Hebert) Barr) in the southern region, and Z. variegatus and rice yellow mottle virus (genus Sobemovirus) in central Benin. The most important rice storage constraint was rodent attacks and the surveyed farmers proposed 13 key solutions to minimize constraints related to rice storage. Among various pest control methods recorded, farmers used mainly synthetic chemical pesticides. However, the Beninese National Pesticide Management Committee (CNGP) does not recommend most of pesticides used by farmers for rice protection (prohibited pesticides or intended for the protection of other crops). Farming experience, family size, region and number of observed pests have significantly influenced farmers' decision to use pesticides. CONCLUSION The rice pests perceived by farmers as important vary significantly across regions. These results suggest that integrated pest management programmes which target rice pests accounting for these regional differences will be more effective. The identified variables that influence the use of pesticides must be taken in account in the development of strategies which will encourage farmers to use ecofriendly pest management.
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Affiliation(s)
- Joelle Toffa
- Ecole Nationale Supérieure des Biosciences et Biotechnologies Appliquées (ENSBBA), Université Nationale des Sciences, Technologies, Ingénierie et Mathématiques (UNSTIM), Dassa-Zoumé, Benin
- Jeune équipe associée à l'IRD (JEAI-GRAB), Dassa-Zoumé, BP 14, Benin
| | - Yêyinou Laura Estelle Loko
- Ecole Nationale Supérieure des Biosciences et Biotechnologies Appliquées (ENSBBA), Université Nationale des Sciences, Technologies, Ingénierie et Mathématiques (UNSTIM), Dassa-Zoumé, Benin
- Jeune équipe associée à l'IRD (JEAI-GRAB), Dassa-Zoumé, BP 14, Benin
| | - Gustave Djedatin
- Ecole Nationale Supérieure des Biosciences et Biotechnologies Appliquées (ENSBBA), Université Nationale des Sciences, Technologies, Ingénierie et Mathématiques (UNSTIM), Dassa-Zoumé, Benin
- Jeune équipe associée à l'IRD (JEAI-GRAB), Dassa-Zoumé, BP 14, Benin
| | - Charlemagne Dsj Gbemavo
- Ecole Nationale Supérieure des Biosciences et Biotechnologies Appliquées (ENSBBA), Université Nationale des Sciences, Technologies, Ingénierie et Mathématiques (UNSTIM), Dassa-Zoumé, Benin
- Jeune équipe associée à l'IRD (JEAI-GRAB), Dassa-Zoumé, BP 14, Benin
| | - Azize Orobiyi
- Ecole Nationale Supérieure des Biosciences et Biotechnologies Appliquées (ENSBBA), Université Nationale des Sciences, Technologies, Ingénierie et Mathématiques (UNSTIM), Dassa-Zoumé, Benin
- Jeune équipe associée à l'IRD (JEAI-GRAB), Dassa-Zoumé, BP 14, Benin
| | - Cyrille Tchakpa
- Ecole Nationale Supérieure des Biosciences et Biotechnologies Appliquées (ENSBBA), Université Nationale des Sciences, Technologies, Ingénierie et Mathématiques (UNSTIM), Dassa-Zoumé, Benin
- Jeune équipe associée à l'IRD (JEAI-GRAB), Dassa-Zoumé, BP 14, Benin
| | - Eben-Ezer Ewedje
- Ecole Nationale Supérieure des Biosciences et Biotechnologies Appliquées (ENSBBA), Université Nationale des Sciences, Technologies, Ingénierie et Mathématiques (UNSTIM), Dassa-Zoumé, Benin
- Jeune équipe associée à l'IRD (JEAI-GRAB), Dassa-Zoumé, BP 14, Benin
| | - François Sabot
- Jeune équipe associée à l'IRD (JEAI-GRAB), Dassa-Zoumé, BP 14, Benin
- DIADE UMR IRD/UM-Centre IRD de Montpellier, Montpellier Cedex 5, France
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Singleton GR, Lorica RP, Htwe NM, Stuart AM. Rodent management and cereal production in Asia: Balancing food security and conservation. PEST MANAGEMENT SCIENCE 2021; 77:4249-4261. [PMID: 33949075 DOI: 10.1002/ps.6462] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 05/02/2021] [Accepted: 05/04/2021] [Indexed: 06/12/2023]
Abstract
Rodents present a major problem for food security in Asia where smallholder farming families are particularly vulnerable. We review here recent developments in the biology and management of rodent pests in cereal cropping systems in Asia. The past decade has seen a strong focus on ecologically-based rodent management (EBRM), its adoption in field studies significantly increased rice yields (6-15%) and income (>15%) in seven Asian countries. EBRM principles have also been successfully applied to maize in China. We provide case studies on EBRM in Cambodia, on interactions between rodent pests and weeds, and on the importance of modified wetlands for biodiversity and rodent pest management. Knowledge on post-harvest impacts of rodents is increasing. One research gap is the assessment of human health impacts from a reduction of rodent densities in and around houses. We identify 10 challenges for the next decade. For example, the need for population modelling, a valuable tool missing from our toolbox to manage rodent pests in cereal systems. We also need to understand better the interactive effects of cropping intensification, conservation agriculture and climate change. Finally, new management approaches such as fertility control are on the horizon and need to be considered in the context of smallholder cereal farming systems and mitigating health risks from zoonotic diseases associated with rodents. © 2021 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Affiliation(s)
- Grant R Singleton
- Natural Resources Institute, University of Greenwich, Kent, UK
- Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ, USA
- International Rice Research Institute, Los Baños, Philippines
| | - Renee P Lorica
- Natural Resources Institute, University of Greenwich, Kent, UK
- International Rice Research Institute, Los Baños, Philippines
- Department of Forest Biological Sciences, College of Forestry & Natural Resources, University of the Philippines Los Baños, Los Baños, Philippines
| | - Nyo Me Htwe
- Plant Protection Division, Department of Agriculture, Ministry of Agriculture, Livestock and Irrigation, Yangon, Myanmar
| | - Alexander M Stuart
- International Rice Research Institute, Los Baños, Philippines
- Pesticide Action Network UK, Brighthelm Centre, Brighton, UK
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Kiyokawa Y, Tanikawa T, Ootaki M, Parsons MH. Social distancing measures differentially affected rats in North America and Tokyo. JOURNAL OF PEST SCIENCE 2021; 95:79-86. [PMID: 34248453 PMCID: PMC8259536 DOI: 10.1007/s10340-021-01405-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 06/19/2021] [Accepted: 06/28/2021] [Indexed: 06/13/2023]
Abstract
UNLABELLED Because rats are commensal organisms that depend on human activities for food, shifts in human behavior will have pronounced effects on local rat populations. In the spring of 2020, social distancing measures were implemented globally to curtail the spread of SARS-CoV-2. This presented a unique opportunity to obtain information regarding the immediate effects of shifts in human behavior on rat populations in a variety of countries. In response to increased sightings of rats in the USA that were reported in American media, we analyzed the changes in the number of public service calls in Tokyo, Japan. We found that the number of calls increased after the implementation of social distancing measures, suggesting that rat sightings had also increased in Tokyo. We then surveyed the changes in the business activities of pest management professionals in the USA, Canada, and Tokyo. We found that the activities were increased in 50 to 60% of the respondents from the USA and Canada. In contrast, 60 to 70% of the respondents from Tokyo answered that their activities were not changed. These results implied that, following the implementation of social distancing measures, rat infestations increased in North America, but not in Tokyo. The survey also suggested that roof rats were considered to be the predominant rodent species in Tokyo. This may account for the limited infestations in Tokyo because roof rats are more sedentary than brown rats. Taken together, our findings suggest that social distancing measures differentially affected rat populations in North America and Tokyo. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1007/s10340-021-01405-z.
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Affiliation(s)
- Yasushi Kiyokawa
- Laboratory of Veterinary Ethology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657 Japan
| | - Tsutomu Tanikawa
- Tokyo Pest Control Association, 2-9-8 Kajicho, Chiyoda-ku, Tokyo, 101-0044 Japan
| | - Masato Ootaki
- Laboratory of Veterinary Ethology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657 Japan
| | - Michael H. Parsons
- Department of Biological Sciences, Fordham University, 441 East Fordham Road, Bronx, NY 10458 USA
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The effect of COVID19 pandemic restrictions on an urban rodent population. Sci Rep 2021; 11:12957. [PMID: 34155237 PMCID: PMC8217515 DOI: 10.1038/s41598-021-92301-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 06/03/2021] [Indexed: 11/08/2022] Open
Abstract
Shortly after the enactment of restrictions aimed at limiting the spread of COVID-19, various local government and public health authorities around the world reported an increased sighting of rats. Such reports have yet to be empirically validated. Here we combined data from multi-catch rodent stations (providing data on rodent captures), rodent bait stations (providing data on rodent activity) and residents' complaints to explore the effects of a six week lockdown period on rodent populations within the City of Sydney, Australia. The sampling interval encompassed October 2019 to July 2020 with lockdown defined as the interval from April 1st to May 15th, 2020. Rodent captures and activity (visits to bait stations) were stable prior to lockdown. Captures showed a rapid increase and then decline during the lockdown, while rodent visits to bait stations declined throughout this period. There were no changes in the frequency of complaints during lockdown relative to before and after lockdown. There was a non-directional change in the geographical distribution of indices of rodent abundance suggesting that rodents redistributed in response to resource scarcity. We hypothesize that lockdown measures initially resulted in increased rodent captures due to sudden shortage of human-derived food resources. Rodent visits to bait stations might not show this pattern due to the nature of the binary data collected, namely the presence or absence of a visit. Relocation of bait stations driven by pest management goals may also have affected the detection of any directional spatial effect. We conclude that the onset of COVID-19 may have disrupted commensal rodent populations, with possible implications for the future management of these ubiquitous urban indicator species.
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Andreassen HP, Sundell J, Ecke F, Halle S, Haapakoski M, Henttonen H, Huitu O, Jacob J, Johnsen K, Koskela E, Luque-Larena JJ, Lecomte N, Leirs H, Mariën J, Neby M, Rätti O, Sievert T, Singleton GR, van Cann J, Vanden Broecke B, Ylönen H. Population cycles and outbreaks of small rodents: ten essential questions we still need to solve. Oecologia 2021; 195:601-622. [PMID: 33369695 PMCID: PMC7940343 DOI: 10.1007/s00442-020-04810-w] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 11/19/2020] [Indexed: 12/25/2022]
Abstract
Most small rodent populations in the world have fascinating population dynamics. In the northern hemisphere, voles and lemmings tend to show population cycles with regular fluctuations in numbers. In the southern hemisphere, small rodents tend to have large amplitude outbreaks with less regular intervals. In the light of vast research and debate over almost a century, we here discuss the driving forces of these different rodent population dynamics. We highlight ten questions directly related to the various characteristics of relevant populations and ecosystems that still need to be answered. This overview is not intended as a complete list of questions but rather focuses on the most important issues that are essential for understanding the generality of small rodent population dynamics.
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Affiliation(s)
- Harry P Andreassen
- Faculty of Applied Ecology, Agricultural Sciences and Biotechnology, Inland Norway University of Applied Sciences, Campus Evenstad, 2480, Koppang, Norway
| | - Janne Sundell
- Lammi Biological Station, University of Helsinki, Pääjärventie 320, 16900, Lammi, Finland
| | - Fraucke Ecke
- Department of Wildlife, Fish, and Environmental Studies, Swedish University of Agricultural Sciences, Skogsmarksgränd, 90183, Umeå, Sweden
| | - Stefan Halle
- Institute of Ecology and Evolution, Friedrich Schiller University Jena, Dornburger Str. 159, 07743, Jena, Germany
| | - Marko Haapakoski
- Department of Biological and Environmental Science, Konnevesi Research Station, University of Jyväskylä, P.O. Box 35, 40014, Jyväskylä, Finland
| | - Heikki Henttonen
- Terrestrial Population Dynamics, Natural Resources Institute Finland, Latokartanonkaari 9, 00790, Helsinki, Finland
| | - Otso Huitu
- Terrestrial Population Dynamics, Natural Resources Institute Finland, Latokartanonkaari 9, 00790, Helsinki, Finland
| | - Jens Jacob
- Federal Research Centre for Cultivated Plants, Vertebrate Research, Julius Kühn-Institut, Toppheideweg 88, 48161, Münster, Germany
| | - Kaja Johnsen
- Faculty of Applied Ecology, Agricultural Sciences and Biotechnology, Inland Norway University of Applied Sciences, Campus Evenstad, 2480, Koppang, Norway
| | - Esa Koskela
- Department of Biological and Environmental Science, University of Jyväskylä, P.O. Box 35, 40014, Jyväskylä, Finland
| | - Juan Jose Luque-Larena
- Departamento de Ciencias Agroforestales, Escuela Tecnica Superior de Ingenierıas Agrarias, Universidad de Valladolid, Campus La Yutera, Avenida de Madrid 44, 34004, Palencia, Spain
| | - Nicolas Lecomte
- Canada Research Chair in Polar and Boreal Ecology and Centre D'Études Nordiques, Department of Biology, Université de Moncton, 18 Avenue Antonine-Maillet, Moncton, NB, E1A 3E9, Canada
| | - Herwig Leirs
- Evolutionary Ecology Group, Department of Biology, University of Antwerp, Universiteitslain 1, 2610, Wilrijk, Belgium
| | - Joachim Mariën
- Evolutionary Ecology Group, Department of Biology, University of Antwerp, Universiteitslain 1, 2610, Wilrijk, Belgium
| | - Magne Neby
- Faculty of Applied Ecology, Agricultural Sciences and Biotechnology, Inland Norway University of Applied Sciences, Campus Evenstad, 2480, Koppang, Norway
| | - Osmo Rätti
- Arctic Centre, University of Lapland, P.O. Box 122, 96101, Rovaniemi, Finland
| | - Thorbjörn Sievert
- Department of Biological and Environmental Science, Konnevesi Research Station, University of Jyväskylä, P.O. Box 35, 40014, Jyväskylä, Finland
| | - Grant R Singleton
- International Rice Research Institute, DAPO Box 7777, Metro Manila, Philippines
- Natural Resources Institute, University of Greenwich, Chatham Marine, Kent, ME4 4TB, UK
| | - Joannes van Cann
- Department of Biological and Environmental Science, University of Jyväskylä, P.O. Box 35, 40014, Jyväskylä, Finland
| | - Bram Vanden Broecke
- Evolutionary Ecology Group, Department of Biology, University of Antwerp, Universiteitslain 1, 2610, Wilrijk, Belgium
| | - Hannu Ylönen
- Department of Biological and Environmental Science, Konnevesi Research Station, University of Jyväskylä, P.O. Box 35, 40014, Jyväskylä, Finland.
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Shiels AB, Lombard CD, Shiels L, Hillis-Starr Z. Invasive rat establishment and changes in small mammal populations on Caribbean Islands following two hurricanes. Glob Ecol Conserv 2020. [DOI: 10.1016/j.gecco.2020.e00986] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Htwe NM, Singleton GR, Johnson DE. Interactions between rodents and weeds in a lowland rice agro-ecosystem: the need for an integrated approach to management. Integr Zool 2019; 14:396-409. [PMID: 30983096 PMCID: PMC6771852 DOI: 10.1111/1749-4877.12395] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Rodents and weeds are important pests to rice crops in Southeast Asia. The interaction between these 2 major pests is poorly documented. In temperate cereal systems, seeds of grass weeds can be an important food source for rodents and weed cover along crop margins provides important refuge for rodents. In 2012 and 2013, a replicated study (n = 4) in Bago, Myanmar compared 4 treatments (rodents and weeds; no rodents and weeds; rodents and no weeds; no rodents and no weeds) each of 0.25 ha in transplanted rice. Weeds were managed with hand weeding in the wet season, and hand weeding and herbicides in the dry season. Plastic fences were installed to exclude rodents. We examined the weed cover and relative abundance of weed species, rodent damage, rodent population dynamics and rice yield loss caused by rodents and weeds. The dominant rodent species was Bandicota bengalensis. In the dry season, Cyperus difformis was dominant at the tillering stage and Echinochloa crus‐galli was the dominant weed species at the booting stage. In the wet season E. crus‐galli was a dominant weed throughout the season. Damage by rodents was higher in the dry season. There were larger economic benefits for best weed management and effective rodent control in the dry season (258 US$/ha) than in the wet season (30 US$/ha). Concurrent control of weeds in and around rice fields combined with coordinated community trapping of rodents during the early tillering stage and ripening stage of rice are recommended management options.
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Affiliation(s)
- Nyo Me Htwe
- Plant Protection Division, Department of Agriculture, Ministry of Agriculture, Livestock and Irrigation, Myanmar
| | - Grant R Singleton
- International Rice Research Institute, DAPO Box 7777, Metro Manila, Philippines.,Natural Resources Institute, University of Greenwich, Chatham Maritime, Kent, UK
| | - David E Johnson
- International Rice Research Institute, DAPO Box 7777, Metro Manila, Philippines
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Htwe NM, Singleton GR. Is quantity or quality of food influencing the reproduction of rice-field rats in the Philippines? WILDLIFE RESEARCH 2014. [DOI: 10.1071/wr13108] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Context
Asynchronous or aseasonal planting of rice crops can extend the period when high-quality food is available to rodents. Consequently, rodents may extend their breeding season, increasing population densities. An improved understanding of the effects of food availability and quality on rodent reproduction may enable better forecasts of high rodent population densities in response to asynchronous or aseasonal planting of crops.
Aim
The present study examined the association between the quality and quantity of food and the reproductive success of female rice-field rats, Rattus tanezumi and Rattus argentiventer, in a lowland rice landscape in the Philippines.
Methods
We evaluated the main dietary components of female rats on two different islands through a cropping season during the 2010 wet season. The breeding performance of 60 female R. tanezumi and 60 R. argentiventer individuals was measured.
Key results
Our findings indicated the following: (1) the main dietary items for females of both rodent species during the main breeding season (the booting stage to harvest) were rice panicles and rice seeds; (2) the high protein content of the rice crop at the tillering stage triggered the onset of the main breeding season, leading to the highest rates of conception during the booting and ripening stages; (3) the quantity of food available at the stubble stage provided sufficient nutrient to maintain pregnancy and lactation by females; and (4) asynchronous planting and poor harvest technology could extend the breeding season of rice-field rats.
Conclusions
We contend that the extension of the growing season by 3–4 weeks provides high-quality food for rodents, which in turn provides sufficient conditions for higher population densities. The availability of spilled rice grain at the stubble stage is a source of good-quality food for pregnant and lactating females, allowing extension of the breeding season.
Implications
Synchronous planting (within 2 weeks) with good post-harvest management of rice stubble are important to prevent high population densities of rice-field rats in lowland rice landscapes in the Philippines.
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Jacob J. Vertebrate pest management: science and application. PEST MANAGEMENT SCIENCE 2013; 69:321-322. [PMID: 23417828 DOI: 10.1002/ps.3496] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
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