African Elephants Adjust Speed in Response to Surface-Water Constraint on Foraging during the Dry-Season
نویسندگان
چکیده
Most organisms need to acquire various resources to survive and reproduce. Individuals should adjust their behavior to make optimal use of the landscape and limit the costs of trade-offs emerging from the use of these resources. Here we study how African elephants Loxodonta africana travel to foraging places between regular visits to waterholes. Elephant herds were tracked using GPS collars during two consecutive dry seasons in Hwange National Park, Zimbabwe. We segmented each individual movement track at each visit to water to define foraging trips, and then used trip-level statistics to build an understanding of movement strategies. Travel speed within these individually-consistent movement bouts was also analyzed to understand if speed was better linked to distance to water or progression in the trip over time. We found that elephants went further from water when drinking less often, which could result from a trade-off between drinking and foraging in less depleted, far from water, places. Speed increased towards the beginning and the end of the trips, and was also greater than observed during the wet season, suggesting that elephants were trying to save time. Numerous short trips traveled at greater speed, particularly when commuting to a different waterhole, was tentatively explained by the inability to drink at specific waterholes due to intra-specific interference. Unexpectedly elephants did not always minimize travel time by drinking at the closest waterhole, but the extra distance traveled remained never more than a few kilometers. Our results show how individuals may adjust movement behavior to deal with resource trade-offs at the landscape scale. We also highlight how behavioral context, here progression in the trip, may be more important than spatial context, here distance to water, in explaining animal movement patterns.
منابع مشابه
Seasonal Diet and Prey Preference of the African Lion in a Waterhole-Driven Semi-Arid Savanna
Large carnivores inhabiting ecosystems with heterogeneously distributed environmental resources with strong seasonal variations frequently employ opportunistic foraging strategies, often typified by seasonal switches in diet. In semi-arid ecosystems, herbivore distribution is generally more homogeneous in the wet season, when surface water is abundant, than in the dry season when only permanent...
متن کاملResponse of African Elephants (Loxodonta africana) to Seasonal Changes in Rainfall
The factors that trigger sudden, seasonal movements of elephants are uncertain. We hypothesized that savannah elephant movements at the end of the dry season may be a response to their detection of distant thunderstorms. Nine elephants carrying Global Positioning System (GPS) receivers were tracked over seven years in the extremely dry and rugged region of northwestern Namibia. The transition d...
متن کاملCassava Bran– Fish Processing Waste as Dry Season Feed Resources for Sheep in Nigeria Southern Guinea Savannah
Seasonal variability impact on livestock production and management stems from poor pasture quality and quantity as well as shortage of water. During wet season, there is usually sufficient quantity of pasture in good quality for animal consumption; but during dry season, there is always insufficient pasture as well as shortage of water for livestock consumption. As a result of these, exploratio...
متن کاملSpatiotemporal Variation and the Role of Wildlife in Seasonal Water Quality Declines in the Chobe River, Botswana
Sustainable management of dryland river systems is often complicated by extreme variability of precipitation in time and space, especially across large catchment areas. Understanding regional water quality changes in southern African dryland rivers and wetland systems is especially important because of their high subsistence value and provision of ecosystem services essential to both public and...
متن کاملEffects of seasonal variation in prey abundance on field metabolism, water flux, and activity of a tropical ambush foraging snake.
The responses of animals to seasonal food shortages can have important consequences for population dynamics and the structure and function of food webs. We investigated how an ambush foraging snake, the northern death adder Acanthophis praelongus, responds to seasonal fluctuations in prey availability in its tropical environment. In the dry season, field metabolic rates and water flux, as measu...
متن کامل