title: Daily microhabitat shifting of solitarious-phase Desert locust adults: implications for meaningful population monitoring.
abstract: The Desert locust Schistocerca gregaria is a major world pest that causes substantial agricultural and economic damage. Effective pest control relies on effective monitoring, which requires knowledge of locust microhabitat selection. Yet little is known about microhabitat selection of solitarious adult locusts in the field. We conducted field surveys to investigate fine-scale diel temporal and spatial distributions of solitarious adults in the Sahara Desert in Mauritania, a major breeding and recession area. We found that solitarious adults moved among different, specific microhabitats throughout the 24-h period in a cyclical manner. At night, they roosted in trees, moved to the ground to feed shortly after dawn, sheltered in low vegetation during the hot midday, and returned to the ground in the late afternoon. Hence, they switched microhabitats and plant species throughout each day. These cyclical daily movements among diverse microhabitats and specific plant species were correlated with time of day, light intensity, temperature, humidity, and specific plant species, and may relate to anti-predator defence, thermoregulation, and feeding. The present study suggests that locust monitoring should be adjusted, based on time of day, locust age, phase state and relative abundance of specific plant species. For example, we recommend surveying ground after morning and trees at night, for solitarious adults, when at low density.
authors.affiliation: The Mauritanian Desert Locust Centre, Centre National de Lutte Antiacridienne (CNLA), BP 665, Nouakchott, Mauritania ; Hakubi Center for Advanced Research and Laboratory of Insect Ecology, Graduate School of Agriculture Kyoto University, Kyoto, 606-8502 Japan.
authors.forename: Koutaro Ould
authors.initials: KO
authors.lastname: Maeno
authors.affiliation: The Mauritanian Desert Locust Centre, Centre National de Lutte Antiacridienne (CNLA), BP 665, Nouakchott, Mauritania.
authors.forename: Sidi
authors.initials: S
authors.lastname: Ould Ely
authors.affiliation: Japan International Research Center for Agricultural Sciences (JIRCAS), Ohwash 1-1, Tsukuba, Ibaraki 305-8686 Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Nakamura
authors.affiliation: Département des Sciences Biologiques et de la Protection des Végétaux, Institut Supérieur Agronomique de Chott-Mariem, BP 47, 4042 Chott-Mariem, Sousse, Tunisia.
authors.forename: Khemais
authors.initials: K
authors.lastname: Abdellaoui
authors.affiliation: Centre National de Lutte contre le Criquet pèlerin, BP E-4281, Quartier du fleuve, Rue 313, Porte 261, Bamako, Mali.
authors.forename: Sory
authors.initials: S
authors.lastname: Cissé
authors.affiliation: The Mauritanian Desert Locust Centre, Centre National de Lutte Antiacridienne (CNLA), BP 665, Nouakchott, Mauritania.
authors.forename: Mohamed El Hacen
authors.initials: Mel H
authors.lastname: Jaavar
authors.affiliation: The Mauritanian Desert Locust Centre, Centre National de Lutte Antiacridienne (CNLA), BP 665, Nouakchott, Mauritania.
authors.forename: Sid'Ahmed
authors.initials: S
authors.lastname: Ould Mohamed
authors.affiliation: The Mauritanian Desert Locust Centre, Centre National de Lutte Antiacridienne (CNLA), BP 665, Nouakchott, Mauritania.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Atheimine
authors.affiliation: The Mauritanian Desert Locust Centre, Centre National de Lutte Antiacridienne (CNLA), BP 665, Nouakchott, Mauritania.
authors.forename: Mohamed Abdallahi
authors.initials: MA
authors.lastname: Ould Babah
keywords: Defensive behaviour; Density-dependent phase polyphenism; Monitoring; Schistocerca gregaria; Solitarious locusts; Thermoregulation