Antelope mating strategies facilitate invasion of grasslands by a woody weed

Abstract

Intra and interspecifi c variation in frugivore behaviour can have important consequences for seed dispersal outcomes. However, most information comes from among-species comparisons, and within-species variation is relatively poorly understood. We examined how large intraspecifi c diff erences in the behaviour of a native disperser, blackbuck antelope Antilope cervicapra , infl uence dispersal of a woody invasive, Prosopis julifl ora , in a grassland ecosystem. Blackbuck disperse P. julifl ora seeds through their dung. In lekking blackbuck populations, males defend clustered or dispersed mating territories. Territorial male movement is restricted, and within their territories males defecate on dung-piles. In contrast, mixed-sex herds range over large areas and do not create dung-piles. We expected territorial males to shape seed dispersal patterns, and seed deposition and seedling recruitment to be spatially localized. Territorial males had a disproportionately large infl uence on seed dispersal. Adult males removed twice as much fruit as females, and seed arrival was disproportionately high on territories. Also, because lek-territories are clustered, seed arrival was spatially highly concentrated. Seedling recruitment was also substantially higher on territories compared with random sites, indicating that the local concentration of seeds created by territorial males continued into high local recruitment of seedlings. Territorial male behaviour may, thus, result in a distinct spatial pattern of invasion of grasslands by the woody P. julifl ora . An ex situ experiment showed no benefi cial eff ect of dung and a negative eff ect of light on seed germination. We conclude that large intraspecifi c behavioural diff erences within frugivore populations can result in signifi cant variation in their eff ectiveness as seed dispersers. Mating strategies in a disperser could shape seed dispersal, seedling recruitment and potentially plant distribution patterns. Th ese mating strategies may aid in the spread of invasives, such as P. julifl ora , which could, in turn, negatively infl uence the behaviour and ecology of native dispersers.

Identification of invasion status using a habitat invasibility assessment model: The case of Prosopis species in the dry zone of Myanmar

“…Prosopis spreads naturally from land-rehabilitation sites through seed dispersal by stream flow and in the dung of livestock feeding on Prosopis pods (Sawal et al, 2004;Jadeja et al, 2013). Prosopis is still being planted for restoration of much degraded lands and degraded mountain ranges in the central dry zone of Myanmar (2013 plantation records of the Forest Department and the Dry Zone Greening Department).…”

Biology and Ecological Adaptations of Blackbuck (Antilope Cervicapra): A Review

“…Bulk of seeds dispersing by blackbuck through their digestive system, defecated seeds which fall on the ground and growing there naturally (Chandru et al 2020). Some of the earlier studies reported for the consumption and seed dispersal of P. juliflora in grassland habitat by Antilope cervicapra (Jadeja et al 2013;Corlett 2017;Yamato et al 2020).…”

“…Licking is also perceptible social spectacle in blackbuck and is explicated by the female group size (Isvaran 2000;Isvaran 2005b) and mating strategy. Blackbuck use facial scent gland to mark their territory observed mostly in the days of rut development (Jadeja et al 2013).…”

“…Study shows that Dicanthium annulatum and Prosopis juliflora constitute 35% and 10% respectively to the yearly dry content consumption. Foraging and rate of digestibility are great during monsoon and winter as compared to summer and the dry season (Brashares 2002;Jadeja et al 2013).…”

Optimization of Scat Detection Methods for a Social Ungulate, the Wild Pig, and Experimental Evaluation of Factors Affecting Detection of Scat

“…While much research has been performed to optimize fecal sampling methods for carnivores [ 16 , 17 ], further optimization is necessary for social ungulates, where transect sampling methods may be inadequate to obtain sufficient sample sizes of scat [ 9 ]. Unlike carnivores, many ungulate species avoid roads [ 18 ] and do not form latrine sites (but see [ 19 , 20 ]), requiring additional effort to acquire sufficient sample sizes of scats. The deposition of scat by many herbivores may, however, be greatly influenced by the presence of social structures, such as aggregative behaviors.…”