Brown locust outbreaks and climate variability in southern Africa
Summary The brown locust Locustana pardalina is a major agricultural pest in southern Africa, with populations periodically reaching plague proportions. Management and control would benefit from a predictive capacity at seasonal time scales, as yet unavailable. The results of a study into the dynami...
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crwiley:10.1046/j.1365-2664.2002.00691.x 2024-09-15T18:37:22+00:00 Brown locust outbreaks and climate variability in southern Africa Todd, Martin C. Washington, Richard Cheke, Robert A. Kniveton, Dominic 2002 http://dx.doi.org/10.1046/j.1365-2664.2002.00691.x https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1046%2Fj.1365-2664.2002.00691.x https://besjournals.onlinelibrary.wiley.com/doi/pdf/10.1046/j.1365-2664.2002.00691.x en eng Wiley http://onlinelibrary.wiley.com/termsAndConditions#vor Journal of Applied Ecology volume 39, issue 1, page 31-42 ISSN 0021-8901 1365-2664 journal-article 2002 crwiley https://doi.org/10.1046/j.1365-2664.2002.00691.x 2024-07-23T04:12:53Z Summary The brown locust Locustana pardalina is a major agricultural pest in southern Africa, with populations periodically reaching plague proportions. Management and control would benefit from a predictive capacity at seasonal time scales, as yet unavailable. The results of a study into the dynamics and potential predictability of locust populations in southern Africa are presented here. The number of districts reporting locust control measures was used as a proxy for swarming brown locust populations. Spectral analysis of the annual number of brown locust infestations over southern Africa revealed dominant periodicity at 17·3 years. The data were low‐pass filtered and the low‐frequency and high‐frequency components were retained. The low‐frequency component led the observed 18‐year cycle in southern African rainfall by about 3 years, and was therefore likely to reflect endogenous controls on populations. Variability in the interannual high‐frequency component of brown locust infestations was strongly related to rainfall over the Karoo and Eastern Cape regions of South Africa. The highest correlations were with rainfall over the 12 months prior to the locust season ( r = 0·64) and in particular with rainfall during December ( r = 0·55). Evidence is presented that the high‐frequency component is related to the Pacific El Niño/Southern Oscillation (ENSO) and that high‐frequency locust activity is abnormally high (low) during La Niña (El Niño) events. The high‐frequency component of locust activity correlates positively and negatively, respectively, with sea‐surface temperatures over the tropical western and eastern Pacific Ocean many months in advance of the locust season. Activity also correlates positively (negatively) with sea‐surface temperatures over the south‐west Indian Ocean and the Southern Ocean (west and north‐west Indian Ocean). These relationships occur later than those in the Pacific, developing in the austral winter and peaking in early summer. This pattern of correlations and the associated ... Article in Journal/Newspaper Southern Ocean Wiley Online Library Journal of Applied Ecology 39 1 31 42 |
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Wiley Online Library |
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English |
description |
Summary The brown locust Locustana pardalina is a major agricultural pest in southern Africa, with populations periodically reaching plague proportions. Management and control would benefit from a predictive capacity at seasonal time scales, as yet unavailable. The results of a study into the dynamics and potential predictability of locust populations in southern Africa are presented here. The number of districts reporting locust control measures was used as a proxy for swarming brown locust populations. Spectral analysis of the annual number of brown locust infestations over southern Africa revealed dominant periodicity at 17·3 years. The data were low‐pass filtered and the low‐frequency and high‐frequency components were retained. The low‐frequency component led the observed 18‐year cycle in southern African rainfall by about 3 years, and was therefore likely to reflect endogenous controls on populations. Variability in the interannual high‐frequency component of brown locust infestations was strongly related to rainfall over the Karoo and Eastern Cape regions of South Africa. The highest correlations were with rainfall over the 12 months prior to the locust season ( r = 0·64) and in particular with rainfall during December ( r = 0·55). Evidence is presented that the high‐frequency component is related to the Pacific El Niño/Southern Oscillation (ENSO) and that high‐frequency locust activity is abnormally high (low) during La Niña (El Niño) events. The high‐frequency component of locust activity correlates positively and negatively, respectively, with sea‐surface temperatures over the tropical western and eastern Pacific Ocean many months in advance of the locust season. Activity also correlates positively (negatively) with sea‐surface temperatures over the south‐west Indian Ocean and the Southern Ocean (west and north‐west Indian Ocean). These relationships occur later than those in the Pacific, developing in the austral winter and peaking in early summer. This pattern of correlations and the associated ... |
format |
Article in Journal/Newspaper |
author |
Todd, Martin C. Washington, Richard Cheke, Robert A. Kniveton, Dominic |
spellingShingle |
Todd, Martin C. Washington, Richard Cheke, Robert A. Kniveton, Dominic Brown locust outbreaks and climate variability in southern Africa |
author_facet |
Todd, Martin C. Washington, Richard Cheke, Robert A. Kniveton, Dominic |
author_sort |
Todd, Martin C. |
title |
Brown locust outbreaks and climate variability in southern Africa |
title_short |
Brown locust outbreaks and climate variability in southern Africa |
title_full |
Brown locust outbreaks and climate variability in southern Africa |
title_fullStr |
Brown locust outbreaks and climate variability in southern Africa |
title_full_unstemmed |
Brown locust outbreaks and climate variability in southern Africa |
title_sort |
brown locust outbreaks and climate variability in southern africa |
publisher |
Wiley |
publishDate |
2002 |
url |
http://dx.doi.org/10.1046/j.1365-2664.2002.00691.x https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1046%2Fj.1365-2664.2002.00691.x https://besjournals.onlinelibrary.wiley.com/doi/pdf/10.1046/j.1365-2664.2002.00691.x |
genre |
Southern Ocean |
genre_facet |
Southern Ocean |
op_source |
Journal of Applied Ecology volume 39, issue 1, page 31-42 ISSN 0021-8901 1365-2664 |
op_rights |
http://onlinelibrary.wiley.com/termsAndConditions#vor |
op_doi |
https://doi.org/10.1046/j.1365-2664.2002.00691.x |
container_title |
Journal of Applied Ecology |
container_volume |
39 |
container_issue |
1 |
container_start_page |
31 |
op_container_end_page |
42 |
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1810481731157884928 |